Hello all,
I am new to the board and thought I would try an solicite some advice. I am currently trying to fit a couple of 270 Cummins in my B31, and am having difficulty squeezing the port engine in place. The mixing elbow is for 5" exhaust, and the factory configuration protrudes into the companionway, between the two engine beds. I am trying to do the install without removing the entire deck, and my current exhaust runs almost directly in-line with the shafts. Is there a way to modify the elbow, without having to build a dry exhaust? It seems like I saw an older thread discussing this issue and I was hoping to get some advise. Please let me know your thoughts.
Thanks
Help with 6BTA 270 Install
Moderators: CaptPatrick, mike ohlstein, Bruce
Brian,
Welcome
Follow this link. It will take you to numerous pics of Cummins installs and exhaust layouts.
http://bertram31.com/newbb/viewtopic.ph ... 236d1df910
There are many more, the search function is a useful tool here.
As someone who did many 31 repowers, I'll tell you connecting to a center shaft exhaust and leaving the deck on is not the way to go.
Every one of my repowers the exhaust was moved outboard to allow for the larger turn radius's due to the larger exhaust diameter.
If your elbow is a 5" outlet, you need at least 5" all the way out depending muffler use.
Welcome
Follow this link. It will take you to numerous pics of Cummins installs and exhaust layouts.
http://bertram31.com/newbb/viewtopic.ph ... 236d1df910
There are many more, the search function is a useful tool here.
As someone who did many 31 repowers, I'll tell you connecting to a center shaft exhaust and leaving the deck on is not the way to go.
Every one of my repowers the exhaust was moved outboard to allow for the larger turn radius's due to the larger exhaust diameter.
If your elbow is a 5" outlet, you need at least 5" all the way out depending muffler use.
Welcome,
The short answer is yes it can be done and yes you will probably need to take the decks out.
The engine boxes can be widened and returned befor the cabin door JJ has this done. Generally the engines are moved forward which helps with the exhaust routing. You will probably need to get creative with a saws all to make the turn.
Do the port engine first and then match the starboard.
The short answer is yes it can be done and yes you will probably need to take the decks out.
The engine boxes can be widened and returned befor the cabin door JJ has this done. Generally the engines are moved forward which helps with the exhaust routing. You will probably need to get creative with a saws all to make the turn.
Do the port engine first and then match the starboard.
KR
JP
1977 RLDT "CHIMERA"
JP
1977 RLDT "CHIMERA"
Thanks guys!
The boat had Detroit 6V53 naturals, before, and alot of work was done to make room for these motors. A portion of the deck has been removed, and this gives me some room to work. The exhaust system is already 5", and this was one of the determining factors in choosing these new engines. As for the engine boxes, I have already cut the side panels and am preparing to install some piano hinges on the bottom, so that they will allow for future maintenance. It sounds like I will need to look at moving the hinges inboard...
The boat had Detroit 6V53 naturals, before, and alot of work was done to make room for these motors. A portion of the deck has been removed, and this gives me some room to work. The exhaust system is already 5", and this was one of the determining factors in choosing these new engines. As for the engine boxes, I have already cut the side panels and am preparing to install some piano hinges on the bottom, so that they will allow for future maintenance. It sounds like I will need to look at moving the hinges inboard...
Thanks Bruce,
The deck, on this boat was built with Nida Core, and has a couple layers of glass (biaxle) on the top and bottom. Unfortunately the deck is supported by a series of fiberglass I-beams, which have been attached to the original stringers. The deck is screwed and epoxied to the I-beams and the removal would be a BIG job. At this point, my budget just doesn't allow for it, and I am more interrested in going fishing. Moving the exhaust outboard of the stringers would definitely require removing the deck, not to mention adding new supports for the muffelers and cutting new holes in the transome, etc... I am hoping that I can fabricate a new mixing elbow, and route the exhaust over the fuel tank, but it looks like there is only 5 1/4 " of space, as the deck is about 1" thick. I may have to have a riser built that will cross the gear and enter on the outboard side, instead, which should allow for vibration. My concern is the expense in fabrication. I'm still contemplating all of this. Thanks for all the input. The pictures on the link that you sent were helpful.
The deck, on this boat was built with Nida Core, and has a couple layers of glass (biaxle) on the top and bottom. Unfortunately the deck is supported by a series of fiberglass I-beams, which have been attached to the original stringers. The deck is screwed and epoxied to the I-beams and the removal would be a BIG job. At this point, my budget just doesn't allow for it, and I am more interrested in going fishing. Moving the exhaust outboard of the stringers would definitely require removing the deck, not to mention adding new supports for the muffelers and cutting new holes in the transome, etc... I am hoping that I can fabricate a new mixing elbow, and route the exhaust over the fuel tank, but it looks like there is only 5 1/4 " of space, as the deck is about 1" thick. I may have to have a riser built that will cross the gear and enter on the outboard side, instead, which should allow for vibration. My concern is the expense in fabrication. I'm still contemplating all of this. Thanks for all the input. The pictures on the link that you sent were helpful.
-
mike ohlstein
- Site Admin
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The deck is screwed and glued to the supporting I-beams. It appears to be an epoxy-glue mix. Unfortunately most of the installations by the previous owner either us epoxy or 5200. I can get the 5200 loose with a heat gun, but the epoxy is a different story. I would like to replace the deck an build some gunwale lockers in a couple of years. At this point, I'm just trying to choose my battles with an annual budget in mind.
Thanks,
Brian
Thanks,
Brian
The last 31 I repowered before closing the shop had a glued and screwed deck.
I took a sawz all and just ran it between the bottom of the deck and the deck supports and used a long demolition blade(many blades actually) so I could bend the blade on an angle while running the machine.
Ate right thru the crap, took about a day to do.
Budget? Budget?
Oh silly person, there is no budget when it comes to boat work.
You have much to learn grasshopper.
I took a sawz all and just ran it between the bottom of the deck and the deck supports and used a long demolition blade(many blades actually) so I could bend the blade on an angle while running the machine.
Ate right thru the crap, took about a day to do.
Budget? Budget?
Oh silly person, there is no budget when it comes to boat work.
You have much to learn grasshopper.
-
Harry Babb
- Senior Member
- Posts: 2354
- Joined: Jun 30th, '06, 21:45
- Location: Fairhope Al
- Contact:
Brian
I took a bit of a different approach. After getting this all worked out I understand that other guys have also done their exhaust like I did.
I found myself having to make the same decisions that you are facing right now.
In a nut shell, flip the turbo upside down, rotate the spool back to standard operating position then make everything else fit.
Several things have to be modified to make this work. The heat exchanger has to slide forward a couple of inches, the oil return tube has to be extended, you have to make an air intake "Turnaround", (the brown thing in the pic) the heat exchanger water outlet has to be rotated, and you must install a vent hose from the top of the turbohousing back to the expansion take to keep the turbo from getting air trapped and creating a hot spot.
As far as the exhaust pipe itself, you have to make one of those not matter what you do....so the work for the exhaust itself don't count.
Pretty much the choice is to do fiberglass work/modification or do turbo modification/fabrication.
hb
I took a bit of a different approach. After getting this all worked out I understand that other guys have also done their exhaust like I did.
I found myself having to make the same decisions that you are facing right now.
In a nut shell, flip the turbo upside down, rotate the spool back to standard operating position then make everything else fit.
Several things have to be modified to make this work. The heat exchanger has to slide forward a couple of inches, the oil return tube has to be extended, you have to make an air intake "Turnaround", (the brown thing in the pic) the heat exchanger water outlet has to be rotated, and you must install a vent hose from the top of the turbohousing back to the expansion take to keep the turbo from getting air trapped and creating a hot spot.
As far as the exhaust pipe itself, you have to make one of those not matter what you do....so the work for the exhaust itself don't count.
Pretty much the choice is to do fiberglass work/modification or do turbo modification/fabrication.
hb
hb
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Tony Meola
- Senior Member
- Posts: 7036
- Joined: Jun 29th, '06, 21:24
- Location: Hillsdale, New Jersey
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Brian
I have the 270's. I kept them in the shaft alley since moving to the outside meant if I wanted to keep the glass work to a minimum, I would of had a couple of extra turns and that would have probably meant a 6 inch exhasut. I know JJ tried 5 inch exhaust running down the outside stringer but he kept the exhaust port in the original position. So that meant another two bends at the transom. Created too much back pressure and he had to go to 6, Since I had 5 already I figured keep it in the shaft alley for now and if I ever paint the hull, then I will move it outboard.
Let me see if I have a picture. If I do I will email it to you.
I have the 270's. I kept them in the shaft alley since moving to the outside meant if I wanted to keep the glass work to a minimum, I would of had a couple of extra turns and that would have probably meant a 6 inch exhasut. I know JJ tried 5 inch exhaust running down the outside stringer but he kept the exhaust port in the original position. So that meant another two bends at the transom. Created too much back pressure and he had to go to 6, Since I had 5 already I figured keep it in the shaft alley for now and if I ever paint the hull, then I will move it outboard.
Let me see if I have a picture. If I do I will email it to you.
1975 FBC BERG1467-315
Thanks Guys!
Harry,
Capt. Patrick told me you had done this with the turbo, and I was curious how you made it work. I could see that there were a lot of modifications that would come with it. Thanks for sharing!
It looks like I'm am going to be able to achieve the original plan that I had intended. I am having to cutt the existing stringers down a couple of inches on both engine beds, to allow room for the mixing elbow to pass over the aft motor mounts, which will be on the gear and not the bell housing. I am going to make a 3" custom spool to add to the port-side wich will move the exhaust slightly outboard, as it passes under the deck on the port engine. The starboard mixing elbow will need to be cutt to fit and then modified by the machine shop, to keep it inside of the engine box and companion way. I will have a 6" hole in the aft bulkhead, passing over the fuel tank and joining a 45 degree fiberglass pipe to the muffeler. I will have to remove a wood gusset and deck support to make room, but I have a plan to move the support aft. Hopefully it all works as easy as it sounds. I'll try and send some pictures, as soon as I figure-out how.
Thanks,
Harry,
Capt. Patrick told me you had done this with the turbo, and I was curious how you made it work. I could see that there were a lot of modifications that would come with it. Thanks for sharing!
It looks like I'm am going to be able to achieve the original plan that I had intended. I am having to cutt the existing stringers down a couple of inches on both engine beds, to allow room for the mixing elbow to pass over the aft motor mounts, which will be on the gear and not the bell housing. I am going to make a 3" custom spool to add to the port-side wich will move the exhaust slightly outboard, as it passes under the deck on the port engine. The starboard mixing elbow will need to be cutt to fit and then modified by the machine shop, to keep it inside of the engine box and companion way. I will have a 6" hole in the aft bulkhead, passing over the fuel tank and joining a 45 degree fiberglass pipe to the muffeler. I will have to remove a wood gusset and deck support to make room, but I have a plan to move the support aft. Hopefully it all works as easy as it sounds. I'll try and send some pictures, as soon as I figure-out how.
Thanks,
Brian,
First, not that it matters, but it may, what model is your boat?
If you have gone to the post that Bruce recommended,
http://bertram31.com/newbb/viewtopic.ph ... 236d1df910
you will find my express at the end with a fairly complete photographic explanation of what I did to squeeze in a pair of Cummins 300's. This was a conversion from original gassers. Everybody in our sandbox had a hand in the planning and execution of this transplant and it works beautifully. Routing the 5" exhausts to the outside stringers is a must. You suddenly acquire some much-needed storage below deck. My humble recommendation would be to NOT cheap out in any way because of budget. If you find yourself short at any interval in the process cover the boat and do something else for a while. This will allow you to replenish the strong box and clear the fiberglass from lungs and mind.
If you need any explanations or further photos let me know. Always glad to help a member of the Faithful as they have helped me through the years.
First, not that it matters, but it may, what model is your boat?
If you have gone to the post that Bruce recommended,
http://bertram31.com/newbb/viewtopic.ph ... 236d1df910
you will find my express at the end with a fairly complete photographic explanation of what I did to squeeze in a pair of Cummins 300's. This was a conversion from original gassers. Everybody in our sandbox had a hand in the planning and execution of this transplant and it works beautifully. Routing the 5" exhausts to the outside stringers is a must. You suddenly acquire some much-needed storage below deck. My humble recommendation would be to NOT cheap out in any way because of budget. If you find yourself short at any interval in the process cover the boat and do something else for a while. This will allow you to replenish the strong box and clear the fiberglass from lungs and mind.
If you need any explanations or further photos let me know. Always glad to help a member of the Faithful as they have helped me through the years.
Mikey
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
Thanks Mikey,
Much appreciated. I have had this boat for three years, now, and I have chosen various projects to complete each Winter. This is a project boat for myself and my father, and as much as we would love to pull the trigger and make everything better than new, the fishing is where we find most of the enjoyment. I worked on boats professionally for 15 years, and have overseen and conducted many re-fit projects. Unfortunately I just don't have the same budget, when spending my own money. We have spent around $60,000.00, since March 1st and it is time to find ways to stop the hem riging...
The boat is a FBC 1976 model, so we have even less room to work with. The good news is that it was formerly a commercial snapper boat, and we have insulated fish boxes that hold about 3,000lbs. of fish and ice. There is an express boat next to us that is installing 3306BTA's, and I am jealous of their extra space and budget. We are going to keep the exhaust inboard, for now, and move everything when we replace the deck, in a year, or so.
Thanks,
Brian
Much appreciated. I have had this boat for three years, now, and I have chosen various projects to complete each Winter. This is a project boat for myself and my father, and as much as we would love to pull the trigger and make everything better than new, the fishing is where we find most of the enjoyment. I worked on boats professionally for 15 years, and have overseen and conducted many re-fit projects. Unfortunately I just don't have the same budget, when spending my own money. We have spent around $60,000.00, since March 1st and it is time to find ways to stop the hem riging...
The boat is a FBC 1976 model, so we have even less room to work with. The good news is that it was formerly a commercial snapper boat, and we have insulated fish boxes that hold about 3,000lbs. of fish and ice. There is an express boat next to us that is installing 3306BTA's, and I am jealous of their extra space and budget. We are going to keep the exhaust inboard, for now, and move everything when we replace the deck, in a year, or so.
Thanks,
Brian
i could not explain the situation better then mikey . what could be more explicit you must run the exhaust to the outside. take up the floor and just put down painted plywood for now but don`t spent all that extra money cutting away all that professional underfloor support and welding then take it apart later. just think there is a two foot by eight foot area totally wasted. critical room because it is in the cockpit for wash down hose,ocean anchoring,boat hook, mops,the list goes on and on and the starboard side a huge kill box . i would be lost without it and if you don't` like that reason the the up and over exhaust need no altering of the engine box and with use of mini max mufflers you need no surge tubes. think it over bertram made a perfect cavity between the hull and the outside floor support use it!!!!
capt.bob lico
bero13010473
bero13010473
Thanks guys. I will definitely give some more thought to pulling the deck and going up and over with the exhaust. So far, everything is fitting pretty well, with no changes to the engine boxes, other than making them smaller. We have replaced a long list of items on this boat, and we haven't cut corners or gone cheap, yet. The salon-area needs some major work to get it back to yacht-quality, including removing the fish boxes. I had planned on tackling that project in a couple of years, along with pulling the deck and making room for fish boxes. Fishing and quality of life are just taking priority these days. I can assure you, it will look nice when we finish.
Thanks,
Brian
Thanks,
Brian
Brian,
The budget thing is on everybody's mind and plate. It took me seven years to get Dreamsicle in the water and the salon is still an empty hole, but we are using her, even if not as much as we would like. Bob is right about the deck. Hadn't thought of going with temporary plywood until the budget recovers. With a coat of paint it should do just fine for a few years. I eventually installed Cabrera decks which will come right up with the turn of a few screws. They also come with fish boxes. To save a few shekels I bought only one fish box, the other side is reserved for all those nasty items necessary for the complete fishing boat.
The budget thing is on everybody's mind and plate. It took me seven years to get Dreamsicle in the water and the salon is still an empty hole, but we are using her, even if not as much as we would like. Bob is right about the deck. Hadn't thought of going with temporary plywood until the budget recovers. With a coat of paint it should do just fine for a few years. I eventually installed Cabrera decks which will come right up with the turn of a few screws. They also come with fish boxes. To save a few shekels I bought only one fish box, the other side is reserved for all those nasty items necessary for the complete fishing boat.
Mikey
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
3/18/1963 - -31-327 factory hardtop express, the only one left.
The difference between genius and stupidity is that genius has its limits.
-Albert Einstein
Im also on the fishbox kick.. What a great addition to these boats.. the exhaust naturally goes outside the stringers .. also I got rid of the cockpit panels ...adds 10 squre feet or so under the gunnels. ..good place for gaffs ,nets & a good place for your toe hold pulling something into the boat...
W
W
brian i know this sounds like bulls-it but this giant fish box is God sent . i am the captain of a 510 bertram and a 45' cabo .the fish box on both of them is not even close to what you will have. i have a terrible lower back so i lift the fish with the gin pole gently lay it down on the cockpit floor run salt water thru it`t mouth as i denerve it and slide it into a bed of ice then ice over it . out of the elements ,out of the sun and out of the cockpit.this fish is just under 5' and fit easily into killbox.trust me this is the thing to do.
capt.bob lico
bero13010473
bero13010473
this is the old cockpit sole and no panels on sides as brother ironman indicated . i am building a new cockpit floor out of coos board that has even bigger kill boxes . all underfloor mechanicals completely accessible .removal of side panels make a totally fantastic fishing cockpit, even tackle boxes for quick trolling lure change slide under forward gunwale.
capt.bob lico
bero13010473
bero13010473
Wow Bob!
That's a beautiful boat and a nice tuna! I can see your point about the fishbox room, and I love the gin-pole. I haven't seen one in years.
Incedentally, the fish box I have now, is inside of the salon, and is about 8 feet-long and well insulated. I could feasably fit about 9 tuna that size in it, and still have room for a couple hundred pounds of ice. (former commercial boat) I'll take a picture and send it to you. My entire salon is painted and faired Awlgrip, and can be washed with a hose and dried. This is not my ideal set-up, but it suits me for now, with my current budget. I love your cockpitt layout, especially the deck and luvered teak engine vents. We mostly fish for billfish, here in Port Aransas, and we may keep the occasional tuna, dorado or wahoo, but fishbox room won't be a concern until I begin re-modling the salon.
Thanks for sharing!
That's a beautiful boat and a nice tuna! I can see your point about the fishbox room, and I love the gin-pole. I haven't seen one in years.
Incedentally, the fish box I have now, is inside of the salon, and is about 8 feet-long and well insulated. I could feasably fit about 9 tuna that size in it, and still have room for a couple hundred pounds of ice. (former commercial boat) I'll take a picture and send it to you. My entire salon is painted and faired Awlgrip, and can be washed with a hose and dried. This is not my ideal set-up, but it suits me for now, with my current budget. I love your cockpitt layout, especially the deck and luvered teak engine vents. We mostly fish for billfish, here in Port Aransas, and we may keep the occasional tuna, dorado or wahoo, but fishbox room won't be a concern until I begin re-modling the salon.
Thanks for sharing!
Some Texas fish
Most of these would fit in the box...
Brian I don 't have 1/10 the fishing knowledge of Brewster,jp's and others on this board but I get lucky and have great fishing whereabouts on a everyday basis to go we're they are biting in the last 24hours.i still feel swordfish is the toughest of the big game fish,when they go straight down they take some effort to bring to the boat.Back to your boat they sell pressure treated plywood very cheap use for foors in a outside shed.it will stand up a long time in the cockpit and finish on one side.no screws just a bead of 3m 4000 uv and you can take up in a heartbeat when your ready.just put wrecking bar under one corner and use wedge then go right along and floor pops up.any questions at all on over the top exhaust I will give you pictures and have it made at a real great price from a pro in the business 30 years marine manifolds inc..
capt.bob lico
bero13010473
bero13010473
Thanks Bob,
I actually have material to build the deck myself. I have a couple of sheets of Nida core, and a sheet of Penske Board, both 3/4". I have a few yards of biaxle and plenty of West Systems. I'm using the Penske and biaxle on the bridge, right now. Unfortunatly, with the limited time that I have (weekends-only), I'm afraid I couldn't get it done without paying for help. Not to mention the haul-out storage fees.
Thank you for all of the insight and ideas. I will definitely be making plans for the deck project, in the near future. I figure I can move the exhaust outboard, later. I just need to remove a couple of elbows and rip up the deck. I think I would probably just order one of the Cabrera decks, at this point. I am definately going to need a source for the exhaust elbow.
Thanks!
I actually have material to build the deck myself. I have a couple of sheets of Nida core, and a sheet of Penske Board, both 3/4". I have a few yards of biaxle and plenty of West Systems. I'm using the Penske and biaxle on the bridge, right now. Unfortunatly, with the limited time that I have (weekends-only), I'm afraid I couldn't get it done without paying for help. Not to mention the haul-out storage fees.
Thank you for all of the insight and ideas. I will definitely be making plans for the deck project, in the near future. I figure I can move the exhaust outboard, later. I just need to remove a couple of elbows and rip up the deck. I think I would probably just order one of the Cabrera decks, at this point. I am definately going to need a source for the exhaust elbow.
Thanks!
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