Repowering my boat

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Bill Mckinnon
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Repowering my boat

Post by Bill Mckinnon »

Hey guys need your help. I am leaning toward Yanmar over the Cummins. Any comments on one versus the other. The yanmar's are a little more money but seem easier on the installation side and would reduce the cost. Yard is saying do not have to change shaft or stuts and they have done several 31's already, Cummin would require the larger shafts and Struts, plus increased air flow, Any comments would be great and am sure will be needing more advice as we move forward,

Thanks

Captain Bill Mckinnon
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JP Dalik
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Post by JP Dalik »

Which models are being compared?
KR


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Bill Mckinnon
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Post by Bill Mckinnon »

Soory guys the cummins are the 330 recons and the yanmar are the 315 6 lpy I think
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JP Dalik
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Post by JP Dalik »

Both will need roughly a 20" diameter wheel. The math on that requires minimum 1.5" shafts. So you aren't saving any money at this point on running gear. If you swing a larger diameter wheel go with a heavier(larger diameter) shaft.
Guys have both brands on this board. Each seems to like what they have. It comes down to the ability to get parts and service. Go with your gut, but don't believe you'll be able to run either of those engines on anything less than 1.5".

My opinion, both brands offer roughly the same top end and fue economy. We have Cummins 330 hp with 1.5" shafts and 20" diameter wheels, couldn't be happier with the set up and performance.

Plus you being in Charleston SC that is the home of Cummins Marine you should be able to get some decent support out of that place. I've worked with a couple of VP's from Cummins Atlantic and they are all good people.

Good luck
Either choice is a winner
KR


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In Memory Walter K
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Post by In Memory Walter K »

I have Cummins and I question your guys saying its a more difficult installation and the need for more air for the Cummins. If you're putting 300 hp engines of any brand, you should up your shaft size, especially on a higher rpm Yanmar. I'd be more choosey about your installer as right now he certainly has a credibility gap with me. You won't make a mistake with either engine, but you can make a mistake with an unknowledgeable installer who's dying to get the job. Walter
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Post by Tony Meola »

Bill

I am in the middle of a repower right now. I am putting the 270 remans in. We upped the shaft to 1.5" and I used the old struts, just had them bored out. The installation is not that much more difficult. The differance besides about $10,000 between the engines is the fact that the Yanmar exhaust gives you a little more room. Plus I can keep the current dash set up since the Cummins gauges will fit into the old panel.

The way we have the exhaust run now is down the shaft alley. We did it this way since I did not want to get into repainting. For some reason my boat had 5" exhaust with gassers. If I ran it down the outboard alley then I would of had to go to 6" due to the bends.

I figure in 5 or so years when I probably will paint it, we will shift the exhaust to the outboard alley. The other thing we did was set the rear motor mounts on the bell housing not on the transmissions. We made a bracket to help support the transmission. On the Port engine it allowed us to keep cutting away the new bulkead to a minimum.

If you are going to paint the boat, then I would run the exhaust down the outside alley and then you can add fish box's in the deck or you can just gain storage room.

Maybe JP can chime in since he has the 315's but depending on the year of the boat and the weight the only difference between the 270 Cummins and the 315 Cummins is the aftercooler on the 270 is fresh water cooled and the 315 Salt water cooled. Also about 3 knots at Cruise, but they are only 31 footers and how often are you going to run at 28 knots.

Good luck in you decision, you will not make a mistake with either one, but choose the installer carefully.
J Clark
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Repowering my boat

Post by J Clark »

Bill
I have the Yanmar 6LYA STP engines, in my 31 FBC. I have talked to several of my friends in the Charleston area about the best Yanmar mechanic/installer and they suggest the same person. Call Mike Mattar with HMY in Charleston, he has the name of the yard and mechanic, or give me a call. 843-344-2245.
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Post by IRGuy »

My Cummins 6Bs are rated at 315/330HP, with a max cruise speed of 2,800 RPMs. What speed are the Yanmars rated at, and what transmission ratio are you considering?

My understandig is that Yanmars are higher speed engines and with properly geared transmissions usually produce higher shaft RPMs. Higher shaft RPMs mean you can have smaller prop diameters and/or less pitch, which allow for smaller shafts.

I have been told for this reason it is easier to repower from gas to Yanmar than it is to Cummins because you can save the original shafts and struts.

I had my boat in Charleston for two years, and had Anthony Black of Marine Power in Wadmalaw do some work for me.. a great guy, with good people. I highly recommend him!
Frank B
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Post by J Clark »

Bill,
Tony Black is the same guy, that I have heard about, they say he is the best in our area.
Jim
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Harv
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Post by Harv »

walterk wrote:I have Cummins and I question your guys saying its a more difficult installation and the need for more air for the Cummins. If you're putting 300 hp engines of any brand, you should up your shaft size, especially on a higher rpm Yanmar. I'd be more choosey about your installer as right now he certainly has a credibility gap with me. You won't make a mistake with either engine, but you can make a mistake with an unknowledgeable installer who's dying to get the job. Walter
Walter,

Cummins 330 vs Yanmar 315
Cummins .....more torque
Yanmar ........higher rpm

Cummins......1:56 to 1 transmission reduction
Yanmar.........2 to 1 transmission reduction

Cummins must have 1 1/2 inch shafts due to the torque
Yanmars can get away with 1 3/8 due to the higher rpms

I've been doing my homework and paying special attention to what Capt. Patrick and Bruce tell me. Would Yanmars benefit from 1 1/2 inch shafts? Certainly....the beefier the better, but not necessarily a necessity. After being on Crow's Nest and having Doug pull the tranny throttles instead of the fuel throttles and throwing the boat directly into reverse at 28knots, and not doing any damage to his 1 3/8 inch shafts with his V8 diesels, I think we may be underestimating the strength of
the 1 3/8 inch shafts.
Harv
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Post by JohnCranston »

Per IRGuy's comments,

I'm gonna try the Yanmar 315's with 1.5 to 1 gears and 1 3/8" shafts with 19x2o 4 bladed props in a very light bahia mar. I had the same shafts and props with the Yanmar 170's with 2 to 1 gears. Don't know if I could have bored the struts out again to accept the 1.5" shats considering that they were 1 1/4" to begin with. I'm probably not a lot of help right now, but if I drowned. ya'll will know why.
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bob lico
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Post by bob lico »

bill what do you mean a little more money?the differance beween the two is 10,000 dollars .don`t you think that money would be better spent inproving effiency.capt. pattick building tips;glass shaft logs,enlarged rudders and true up the strakes , a real bottom job with you actually reblocking beteen coats of interlux.the finesh job adding the 10,000 to the above and the recon cummins 315hp will exceed the yanmar6lpa-stp installation without the above changes.--trust me
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capy
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Post by capy »

A month or two after I bought my boat I was going to buy new props(1.6k) for spares from H+H propellor, the guy told me I should upgrade to 1.5 shafts...... at 4.5k cost.

I found props at atlantic propellor for 800 clams

I have been running 2-stroke, oil slingin' dump truck motors in my 31 for 15years, with 1 3/8' shafts.

216 hp, 465ft-lbs torque, 1.5:1 BW73c trannys filled with 30w oil, 21dx19p 3 bladed bronze equipoise with heavy cup............22 knot cruise

These motors easily add an additional ton to the gross weight, plus more for soundown lead...

I have never had a problem ........changed cutlass bearings once, repacked shafts seals twice.

It is like the energizer bunny, it keeps going and going.

Take from this what you will.
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Dug
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Post by Dug »

I have the Yanmar 240's. I did not need to change shafts.

However if I were to have gone with the 315's I would have needed to change shafts per everyone I talked with.

You are repowering. Either way you are spending a good solid chunk of change.

Don't try to "get away with" anything. Just do it right. You will be pissed at something or someone if you short it, and spend $60 G's on a repower to have something stupid set you back because you didn't re-shaft when it was all apart.

Even at 1 3/8" I bought new shafts so I knew where I stood vs. old shafts.

Now, the Cummins and Yanmars are both awesome engines. Depends on service availability as far as I am concerned. I harbor nothing against Cummins except that they have no service coverage in southeastern CT. Yanmar has it covered like a blanket. Thus for me, it was a no brainer. Yanmar. The added blessing was I liked the engines better for me and my uses. They are quieter, smoother, and yes, do run at a higher rpm. In essence for me they are diesels, with all the benefits of diesel, but they perform and act very much like gas engines. No smoke (ok, minor however), quieter, and smooth. They don't shake the boat apart at idle. Not all Cummins do that, but I have seen some.

Again, this is my opinion, and I know those who have Cummins rightfully love them. They are also great engines. In my mind, they are the two ideal set ups for this boat.

Dug
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Post by dougl33 »

I've got 300hp 6BTA's in my 33 Bert. I'm running ZF220a 1.5:1's with 21X22 Mich Nibral DJX (#5 cup) on inch and 3/8's shafts. Just wrapping up my second year. I cruise at 2400rpms (23-24 knots) and top out at 2900rpms (29-30 knots).

My Cummins installer (also the rep for the NE) has been running the same exact setup in his 34 Hatt for 5000+ hours and has never snapped a shaft.

Shoot, just about every 33 Bert that left the factory came with inch and 3/8's shafts, including the 320hp Cats at the end of production.

Make sure the prop doesn't sit to far behind the strut and make sure the key way is spooned and you'll never have a problem.

I like the Cummins, but I've never met anyone who was unhappy with their Yannies either. Save yourself some money and go with the Cummins and stick with inch and 3/8's.
Regards,

Doug L.
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Post by Tony Meola »

The $10,000 wasn't the only reason I went with Cummins. Like Dug said it was a service issue. In Forked River, the Yanmar dealer's reputation was lacking while the Cummins dealer has one of the best reps around. So I went Cummins.

Now the Cummins Rep is also a Yanmar dealer as of 4 weeks ago. I think I still would have stayed Cummins. Money talks and $10,000 is a lot of cash to give to some one when you don't have too.

By the way, as far as I am concerned, the every thing people told me about the dealer was true. Honest as the day is long and a hell of a nice guy.
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Post by scot »

Everything said on this post is true, all valid points. The one thing not mentioned is the flexibility of the shafts.

The 1 3/8 has an advantage over the 1 1/2 shafts from a flexibilty stand point. All boats flex while running and there is merit in the shafts flexing as well. The larger the shaft, the less it will flex. The stress caused by less flexing takes a toll on transmission tail bearings, strut mounts and cutlass bearings.

This is not to say that a boat will have problems with a 1 1/2 shaft, typically they won't. But, installation alignment and structural integrity (hull stiffness) is more critical. The larger the shaft, the closer everything has to be. Typically 1 1/2 presents no problems, however this becomes a real big deal with diameters above 1 1/2.

I would not worry about a "good" 1 3/8 shaft. The shaft material plays a huge roll. A 1 3/8 cut from stout stuff is better than a 1 1/2 made from cheap material any day.

Basically no engines make more shaft snapping torque than a low rpm Detroit, and Capy's appears to have done just fine with 1 3/8 inchers. The lower rpm's produced by a DD dictates a larger diameter prop, hence Capy's 22" diameter wheels. Larger diameter = more stress on the shaft and yet they last 15 years.

Again, the key here is the shaft material and the condition of the shaft itself. Old pitted shafts should be replaced regardless of diameter.

My 1 3/8 cents.
Last edited by scot on Sep 24th, '08, 08:00, edited 1 time in total.
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bob lico
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Post by bob lico »

scot you hit the nail on the head i just did not bother going over this shaft talk over and over.the bert 31 is being converted from a gasser ---guess what laddies all installations you have to remove the shaft anyway to cut lenth to fit diesel, whoever your machine shop will drop the bomb ! the 13/8" shaft is aquanet 19 not good for 315hp diesel and 500 plus lbs of torque.dug is right do it right the first time.think about it; shaft breaks and you lose a 1300.00 dollar prop what did you gain? and generally it only happens when your offshore.all repowering of 31bertram to 315hp diesel you MUST change to capt. patrick rudders. what part of must do you not understand!!!!
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capy
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Post by capy »

scot wrote:Everything said on this post is true, all valid points. The one thing not mentioned is the flexibility of the shafts.

The 1 3/8 has an advantage over the 1 1/2 shafts from a flexibilty stand point. All boats flex while running and there is merit in the shafts flexing as well. The larger the shaft, the less it will flex. The stress caused by less flexing takes a toll on transmission tail bearings, strut mounts and cutlass bearings.

This is not to say that a boat will have problems with a 1 1/2 shaft, typically they won't. But, installation alignment and structural integrity (hull stiffness) is more critical. The larger the shaft, the closer everything has to be. Typically 1 1/2 presents no problems, however this becomes a real big deal with diameters above 1 1/2.

I would not worry about a "good" 1 3/8 shaft. The shaft material plays a huge roll. A 1 3/8 cut from stout stuff is better than a 1 1/2 made from cheap material any day.

Basically no engines make more shaft snapping torque than a low rpm Detroit, and Capy's appears to have done just fine with 1 3/8 inchers. The lower rpm's produced by a DD dictates a larger diameter prop, hence Capy's 22" diameter wheels. Larger diameter = more stress on the shaft and yet they last 15 years.

Again, the key here is the shaft material and the condition of the shaft itself. Old pitted shafts should be replaced regardless of diameter.

My 1 3/8 cents.
15 years is how long I have had it...the original owner did the installation in 1979...so the shafts are closer to 30 years old....
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Tommy
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Post by Tommy »

Bill,

Most agree that both the Cummins and the Yanmars are ideal for repowering the B31s. I had Patrick and Bruce perform my repower to the Yanmar 6LP-STE 315 HPs in 2001 and I've been pleased ever since. My SF will cruise at 30 knots, and is smooth and relatively quiet, however we normally loaf along at an easy 25-26 knots on calm days, burning about 8 gals per hour per side. Bruce said I could get by with the 1 3/8" shafts if I went with the 1.5:1 reduction, but I opted for the 2:1 reduction so I could swing larger wheels (20X23.5 4-blades), so I went ahead and installed new 1.5" shafts. They were able to use the stock struts by boring them and using thin-walled cutless bearings. I also had them convert the shaft seals to the PSS dripless bearings. The engines have performed great over the past 7 years............the only problem is that I don't use it enough!

Tommy
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nic
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Post by nic »

Bill,

You are getting good advice here...the mighty Tennessee, the first Bertram in Australia, was very happy to get the 315hp Yannies (from the U.S.), new bed caps, new shafts (1.5" Aquamet 22), new f/g logs, new struts, new 4 blade 20 x 23 (note the half inch diff. to Island Girl, we have lower Cetane rating in Oz), new air ducts C/- Capt. Pat, overhauled everything else, steering , electronics, wiring, trim tabs, toilet, man when you start you can't stop but it was the best three weeks of my life...we had a team going nearly 20hrs a day.

I would pay attention to Walter's comment...something is wrong with the advice you are getting. Only use people who have a track record with 31s and the engines you are considering...imho. You will save money & time, and get a better job.

Air is very important, critical. Capt. Pat has everything you might need.

If you go the Yannies make sure they rev above specs...around 3950 max under load, others might chime in.

We have the old rudders Bob Lico and they do not steer for sh*t, but we love 'em. High speed rudders we call 'em...you have to stop somewhere, well we do. Anyway, we drink on board, so steering is very subjective.

It'll cost more than you think so that 10k might end up being important. I have a spread sheet, almost complete, with all our costs that I have been promising to post for almost a year but the number is so big I think I should keep it a secret.

We max at 30.5 knots but we tell everyone 32, so when we zoooom past their "30 knot" boats they don't feel so bad.

Either way you go you will have a great boat.

Nic
Hull No. 330 1963 SF "Tennessee"
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Hyena Love
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Post by Hyena Love »

With questionable older small shafts, the money difference was relatively small in upgrading - at least it was for me.

G. Jordan had a line on a machine shop out of Baton R. or thereabouts that built my shafts for a nice price.

Yammar 240's with 1.5 inch shafts in a B28. Partly because I am too stupid to throttle back, tend to pull props at times, and shait man, you should see people slam her in reverse and back to foward when things get fun. I keep telling them - take a little pause when shifting - but then I get all excited and tend to do the same thing me self.

More than one way to skin a cat.
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In Memory Walter K
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Post by In Memory Walter K »

Ernest-By the way, the latest Motor Boating magazine has a very complimentary article about B-28's. Walter
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Hyena Love
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Post by Hyena Love »

Thanks, I will check it out.
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Carl
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Post by Carl »

Sometimes familiarity can be equated to ease.


My business was/is boat shafting, some guys run less then adaquate shafting for years without a hitch. Then when I reccomend upsizing they just think its a sales pitch. What they do not know or do not believe is I also know guys who have run less then adequate shafts and have had problems. I also know guys who have run what was determined to be adequate shafting and still snapped them. More often then not they snap at the worst times...offshore in bad seas...backing into a slip on a windy day.

My thought has been do it once, do it right.
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Post by ed c. »

I have the 315 Yanmars, 1.5"shafts, 20x23 4 blade nibral props, 2:1 gear I used to cruise at 26 to 28 Kts. but now have lowered my speed because of the price of fuel as many others have done. I used to own a 35 bert. with 3208 cats and broke the 1 3/8 shaft. I went to 1 3/4' shafts after that . I feel very secure with the 1.5' shafts on the 31. I don't know how often you will be using your boat, but i put on 300 to 350 hours per season. Good Luck
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ranjr13
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Re: Repowering my boat

Post by ranjr13 »

First off, great site - newcomer to this forum, but not Bertrams. Presently looking at a 31 in nice shape, with original Cummins 504's that are also said to be in nice shape. Will try to get a season or two out of them, then re-power. With the off-chance that either they fail earlier or I decide to move quicker, any thoughts on current model year replacement engines? A lot has happened to make changes in Yanmar and Cummins replacement engines over the past year or so. I'm leaning towards Yanmar, but apparently need to go to the new 8LV-350 motors. Any thoughts would be appreciated, as well as present day price info from any recent boats would be greatly appreciated.
Bob Norton Jr.
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1964 Bertram 31 Soft Top Express
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Re: Repowering my boat

Post by Tony Meola »

Bruce is the best one to answer the Yanmar question, but from what I have heard they are not the engine they used to be. You need to decide on the size engine you want. I put the 270 reman in mine and could not be happier. Jimmy G just put QSB's in his and I know he is happy. You will see the results if you read through his threads.

It is a matter of picking your poison and which engine you have the best access to for parts and service. That will play a big part in your decision making, besides up front cost.
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bob lico
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Re: Repowering my boat

Post by bob lico »

yanmar 8LV-350 is a good motor for it`s original use a toyota land cruiser and thats were it ends. the marinize version is a POS. exactly what you would expect from a company that use a converted gas engine to satisfy the small diesel market. i would not even begin to start explaining but begin with basics ; v-8 in small diesel as oppose to in line 6 like cat,john deere,cummins,mtu,mann,etc. quote from atlantic city yanmar /cat dealer " we don`t sell any they suck"
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Re: Repowering my boat

Post by Navatech »

ranjr13 wrote:First off, great site - newcomer to this forum, but not Bertrams. Presently looking at a 31 in nice shape, with original Cummins 504's that are also said to be in nice shape. Will try to get a season or two out of them, then re-power. With the off-chance that either they fail earlier or I decide to move quicker, any thoughts on current model year replacement engines? A lot has happened to make changes in Yanmar and Cummins replacement engines over the past year or so. I'm leaning towards Yanmar, but apparently need to go to the new 8LV-350 motors. Any thoughts would be appreciated, as well as present day price info from any recent boats would be greatly appreciated.
First, many people will tell you that if you go with a new motor you have to go for the newer tier 3 engines due to EPA regulations... That's true if you're putting the engine in a new build... If you're repowering an older boat that's not true...

Second, why are you considering a repower as opposed to an overhaul of the existing engines?!... Looking for more power?!..
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Re: Repowering my boat

Post by ranjr13 »

Bob - I appreciate your point of view on Yanmars - definitely a personal preference thing. My last boat, a BHM Downeast had a John Deere and it was great. Interestingly enough, the new John Deere equipment I run on land all have Yanmar engines and have never had one issue, and know several with Yanmars in marine application and all very happy.

Navatech - excellent point on the re-power vs. new build. As to why to replace, I guess my gut tells me for the longevity of the boat, to continuously update and improve the level of engineering, you'd go with modern diesels rather than the 504 Cummins V8s. Power, weight, fuel efficiency, and cleanliness are some reasons for the interest in re-powering. That said, doing injectors, rebuilding injector pumps, tuning, prop tuning etc. would all probably help make sure the boat is running as close to 100% efficiency. I guess I should talk to someone familiar with rebuilding the 504's and get an idea of cost/benefit.

Thank you all for the feedback thus far. Bob
Bob Norton Jr.
"Dalmatian - Essex, CT"
1964 Bertram 31 Soft Top Express
Navatech

Re: Repowering my boat

Post by Navatech »

ranjr13 wrote:I guess my gut tells me for the longevity of the boat, to continuously update and improve the level of engineering, you'd go with modern diesels rather than the 504 Cummins V8s. Power, weight, fuel efficiency, and cleanliness are some reasons for the interest in re-powering. That said, doing injectors, rebuilding injector pumps, tuning, prop tuning etc. would all probably help make sure the boat is running as close to 100% efficiency. I guess I should talk to someone familiar with rebuilding the 504's and get an idea of cost/benefit.
Why do you think these engines need replacing?!... Just because of the hour count?!... Or do you have additional indications (e.g. hard to start, smoking, oily sheen in exhausted cooling water)?!...

Speaking as a grease monkey, what I'd do is a compression test on all 16 holes... If your compression is good all you need is some relatively standard maintenance... Since your injectors are already out I'd hook them up to the fuel lines (without putting them back into the head) and turn the engine over... This might involve bending the fuel lines somewhat... If you're getting good spray patterns just put the injectors back... If the spray pattern is not good it's likely only some of the injectors are so afflicted... In that case I'd hook up the afflicted injectors to other fuel lines... That had good spray patterns previously... If the bad spray pattern moves the injector needs service... If the bad spray pattern stays in the same location the fuel injection pump needs servicing... Having said that, injectors need servicing far more frequently then fuel injection pumps...

If you're put off by the above, you can take your injectors and fuel injection pump to diesel shop... However, I'd start by doing ONLY the injectors and then just verifying the spray patterns as described above... To verify that the fuel injection pump is good...

Otherwise, and while you have the covers off the heads, I'd do a valve clearance verification... Other then that, oil, filters and verification of sacrificial zinc "pencils" is really all that's required... One last thing I'd recommend doing is replacing the coolant... But, before you replace it, do a pressure test at about double the working pressure (that should be noted on your tank cap)...

If you don't have good compression you're loosing compression somewhere... It could be valves (in which case you're looking at a head job) and/or it could be rings (in which case you're looking, at least, at a partial rebuild)... This might be a good time to learn how to do a blow-by test... If your test results definitively show blow-by you'll have to consider rebuilding or repowering... If there's no blow-by (likeliest result) then a head job isn't that big a deal...

As for repowering for efficiency's sake, please note that even if you use your boat at triple the average rate (i.e. 300 hours/season) it will take you many years to recoup your repowering "investment"...
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ranjr13
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Re: Repowering my boat

Post by ranjr13 »

Navatech - whoa horsey, that's a ton of great info. From my post, I said "I'm looking at a 1980 with original 504's" and my concerns were if and when I needed to re-power, what today's thoughts are from the experts updated from 7 or 8 years ago when this thread started. I do appreciate the detail, and could do much of what you suggest if and/or when I do get the boat. Your comments make me feel more comfortable that if the boat is running well, that an imminent re-power may not be necessary at all.....thanks again.
Bob Norton Jr.
"Dalmatian - Essex, CT"
1964 Bertram 31 Soft Top Express
Navatech

Re: Repowering my boat

Post by Navatech »

ranjr13 wrote:Navatech - whoa horsey, that's a ton of great info. From my post, I said "I'm looking at a 1980 with original 504's" and my concerns were if and when I needed to re-power, what today's thoughts are from the experts updated from 7 or 8 years ago when this thread started. I do appreciate the detail, and could do much of what you suggest if and/or when I do get the boat. Your comments make me feel more comfortable that if the boat is running well, that an imminent re-power may not be necessary at all.....thanks again.
Well, if you're only looking at a boat you might want to purchase (as opposed to already owning it) make sure to do the following:
  1. Ask about oil analysis... Absence of such is a sign in and of itself...
  2. Ask about maintenance records (engine's log book, receipts etc) ... Absence of such is a sign in and of itself...
  3. At the VERY least, do a compression test before you plunk down ANY money!!! Better yet, have an experienced (in these engines) grease monkey do a full engine survey...
I'm told there used to be great guy around here (before I joined) called Uncle Vic... And he, allegedly, used to say that "the money is in the iron" (or something to that effect)... He had a VERY valid point!!!

Even a good deal will be a very bad deal if you subsequently find out that the engines are shot or at the end of their lives... Conversely, if you know the FULL deal, shot engines or engines approaching the end of their lives, might represent an opportunity if the price is right...
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Re: Repowering my boat

Post by Tony Meola »

Nav

You got it. God rest his soul, Uncle Vic always said "The Money is in the Iron". How true it is. The hull can be a piece of junk, and the boat sell for $20,000 just because they want the running engines.
1975 FBC BERG1467-315
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ranjr13
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Re: Repowering my boat

Post by ranjr13 »

Navatech/Tony - exactly my thoughts. I'm going into the deal budgeting little if anything in the purchase price for the "iron," as UV would say - just considering any life in them as a bonus with a boat that's very original and in nice shape. Thus if they do go a season or two, I'd be ahead of the game. I will get the skinny on service records, oil sampling etc. later this week when we're on-site with the boat. I use Blackstone Labs frequently and always have kits on hand, so will have both engines reviewed in short order if they have not been done lately.

My theory is to go through them, make sure they're running with good injectors, pumps, and tuned, and that the props are correct. If that is the case, according to what I've been able to learn from other threads on this site and from the seller, the boat should cruise around 14-15kts, and top out near 20. I'm not sure about gph at cruise, thinking in the 12gph area but will try to find that data out as well.

I appreciate the feedback. If we do a deal, the boat will see a 3-4 year restoration in between lots of use in the northeast. Will decide by the weekend. Happy New Year everyone - best wishes for a safe and enjoyable 2016.
Bob
Bob Norton Jr.
"Dalmatian - Essex, CT"
1964 Bertram 31 Soft Top Express
Navatech

Re: Repowering my boat

Post by Navatech »

ranjr13 wrote:My theory is to go through them, make sure they're running with good injectors, pumps, and tuned, and that the props are correct. If that is the case, according to what I've been able to learn from other threads on this site and from the seller, the boat should cruise around 14-15kts, and top out near 20. I'm not sure about gph at cruise, thinking in the 12gph area but will try to find that data out as well.
Make sure you can get to the specced top RPM's for the engines...
Last edited by Navatech on Dec 31st, '15, 07:27, edited 1 time in total.
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bob lico
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Re: Repowering my boat

Post by bob lico »

when it come to personal opinion i have one in my boat as generator (MASE) my corp has four small 3000 watt portable generators but they are all L-9 motors same as john deere small tractors absolutely nothing to do with using a Toyota land cruiser engine marinize in a 31 Bertram.they have abandon there stp 315 hp completely as a matter of fact you could hold a complete cylinder head as a ransom actually worth as much as the rest of the entire motor due to customers with a engine that went down due to a drop valve will pay big bucks to get there boat back in water.
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bob lico
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Re: Repowering my boat

Post by bob lico »

one of five need new cylinder head ,Atlantic city has 6, Beval engine builders have four.and Mack Boring the east coast distributors said "Goodnight Dick" no not personal opinion.

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mike ohlstein
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Re: Repowering my boat

Post by mike ohlstein »

The money may be in the iron, but the key is your budget. There are plenty of old diesel engines in service today. They're mostly heavy (for their output), dirty, loud, slow, and in need of TLC.

If you have the resources and prefer a more pleasant B31 experience, don't think twice. No need to reinvent the wheel, either. I got the last of the purpose built Yanmar marine engines that will work in the 31 (the 4LH series) and have no regrets. But if I was repowering today, I'd go with new Cummins in a heartbeat.
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Charlie J
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Re: Repowering my boat

Post by Charlie J »

I have the same 4lha
no problems great engines
1968 hull # 316 - 757
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Bruce
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Re: Repowering my boat

Post by Bruce »

They're mostly heavy (for their output), dirty, loud, slow, and in need of TLC.
Mike,
You describing motors or the board members, it's hard to tell.
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Re: Repowering my boat

Post by mike ohlstein »

I endeavor to remain slightly ambiguous, so as to leave that sliver of doubt for the reader to (mis)interpret for himself.....
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