Carburetor replacement

[coolair]

I am finally getting some extra time to work on the boat.
The boat has been sitting a while. This weekend both motors fired up. But i couldn't keep one running.
The float is stuck, etc etc.
I have the old Chrysler M460 which are the Chrysler marine Ford 460s.
My original carb is a quadrajet.
Do I have them rebuilt or by remains
Or do I replace them with a holly or eddlebrock?

[Bruce]

You can have them rebuilt. Just use someone who actually has a flow bench to check them.

We use a bunch of Holley and Edelbrock (old carter style) carbs. Today's quality is questionable like many things.
If you go with Holley, factory standard gaskets will seep. Make sure they are the upgraded blue gaskets.

If you replace quad jets are spread bores. You'll need an adapter or different intake, both of which could affect height clearance possibly and ads cost.

[Rawleigh]

These guys were good when I got two Carters from them. They test run each carb on a 454 before shipment and have a 6 month warranty. I personally like the Carters (now Edelbrock). They are much simpler that other carbs and have never failed me.

http://www.carburetion.com/

[MarkS]

Keep the quads they are the most fuel efficient 4 barrels you will find for those motors. Find a top shelf carb guy someone who take the time to clean out all the little fuel ports and venturis. I was going to change out a intake and carb on a 350 I have to a aftermarket Holley or Carter (Edlebrock) and my carb guy talked me out of it. The motor runs like a Swiss watch.

[coolair]

For now i stuck with a couple rebuilt quadrajets.
But what are everyone's thoughts on switch over to fuel injection? I did a search, but most of what i found was older info.

[Stephan]

When I got started in 2009 with my Crusader 454s I was thinking about switching to FI.
I took the advice that I should save that $$$ for other items as the increase in efficiency would not return the investment and I would not see significant improvement in the engines behavior at cold start, etc. I also would introduce additional complexity with the injection system.
My engines have spoiled me with many happy hours. I did install an NMEA 2000 network and some Garmin GFS10 fuel flow sensors (nice thing about gas engines is the fuel flow measurement is simple - no return - they just drink it all) in an attempt to determine efficient operations.

Good luck,
Stephan

[Carl]

I had some dockmates with Fuel Injection.

Their motors started a little better then mine when cold or I didn't use boat in a long time.
At a good pace they were a bit more efficient then I was.

I however could tweak my speed a bit and found a few places my boat ran better, fuel wise. It was play with throttle, tabs and check flowmeters. I could also run pretty good at a quicker pace...before the 4 barrels kicked in.
Overall they did better fuel wise and starting.

Now comes the part I like carbs...if they stutter, hard starting or whatever...I always found a way to get them going and make it back. The fix was pretty much always they needed a cleaning and I was good to go again for a $30.00 rebuild kit and a can of carb cleaner.

Fuel injection guys ran great till they didn't...and it wasn't a fix and get home, it was limp home on one motor. Some repairs it was a high pressure fuel pump, a module, a computer, special gaskets... Othe rissue some guys had to go find parts from a defunct company..Marine Power comes to mind. They had parts made and didn't catalog right so it was trial and error on a module or computer...yeah they did the right thing by not charging...but guy was also wasting weeks going back and forth on an already short season. Anyway parts just stop working and so does motor. Parts can be pricey...add those two together with the If this electric thing goes out your not using that motor kept me happy with carbs.

Yes some Fuel injection motors run trouble free like my electronic timing on my boat did for 22 years...others do not.

[Bruce]

When Crusader went to throttle body, as a dealer I had numerous issues. Throttle body thank God, was short lived in marine and then they went to multi port.
Factory multi port was relatively trouble free. Biggest issues were fuel delivery and clogged filters due to many system that used return lines due to the volume of fuel pumped.

After market throttle body retro fit in marine has just come into play designed specific for marine applications. Proper FI needs o2 sensors to work properly in the exhaust to monitor and adjust fuel/air ratio which this system has. Non o2 is a waste of time that use basic tunes to cover a variety of engines and don't work well. Most run real rich.

On a proper factory tuned F I system with all the sensors will save average 10% on throttle body and 20% on multi port of fuel usage.

More important than carb / FI systems are hot spark ignition systems, good plugs and wires. You need a good hot spark to fire the fuel charge.

Can't say how many customers came to me with carb issues and wanted to do something else where I upgraded ignition systems and kept the carbs where not only performance picked up but fuel burn got better (as long as engine is in good shape).

You can also look at it this way. It's only been the last couple of years since nascar ditched carbs for injection and that was only to make all teams even more equal so racing could get even more boring. Before that going over 200 mph with carbs wasn't that difficult. The super speedway used restrictor plates to reduce hp and speed.

Carbs are good.

[coolair]

Ignition upgrade was actually first thing on my list. But some things have changed since I first wrote this. I think I need to switch over to the repower topic!

[Carl]

Ignition upgrade was actually first thing on my list. But some things have changed since I first wrote this. I think I need to switch over to the repower topic!

I hear someone may have a pair of very well broken in, good running 440 takeouts.
Classic boat with classic engines...
LOL


Not good news, what is up with your motors that has you thinking repower?

[coolair]

LOL! Wonder who that is??
Not really bad news. I am finaly having someone finish my deck i just have not had rhe time. I yanked the motors so we can clean up under them and i could freshen up gaskets and paint them. 1 was blowing steam through the breather. But since they are out, my thoughts of clean them up have changed to i might as well rebuild them. Block castings says they are 1979(if i looked it up right), previous owner said they were installed in the 80s but didnt really know. So who knows. But they are 460 fords and exhaust manifolds are hard to come by. May just be easier to buy a set of 454s and throw them in. A set of fuel injected ones like Pete did would be nice.

[Carl]

Beats me, think I read something in one of the posts somewhere...


Thats what got me to really thinking...I wanted to have rear main Rope Seal replaced, getting tired of diapers in bilge.

But once they are out and I start going through them the project snowballs.


...and then comes how much does one put into 40 year old motors.



I too was leaning towards Petes setup...if a simple motor swap I might have done that, but running gear needed to be changed and numbers started going up further.

Then I was back to leave well enough alone and just keep running them.


Tough call...

[coolair]

I dont really want to change the running gear. I my trannsmissions should work. But didnt think about the shafts needing to be different.

[Tony Meola]

Matt

Your shafts should be 1 3/8. Should not be a problem with most gas installations.

[Carl]

Matt

Your shafts should be 1 3/8. Should not be a problem with most gas installations.

I have 1-1/4" shafts, that is why I said I'd have to change...that and I have no room to turn a wheel over 16" with my 10° shaft setup. Struts for 1-1/4 are super thin wall, no meat to bore. So it's shafts, struts, shaft log as angle changes...and larger wheels. Too much work and expense to stay gas.

If I had 1-3/8 It would have been a simpler swap.

[Craig Mac]

Years ago--- monel was used for shafts----not sure the cost but 1 1/4 monel is stronger and you don't have to deal with upsizing the struts. Not even sure you can find monel these days.

[Carl]

Years ago--- monel was used for shafts----not sure the cost but 1 1/4 monel is stronger and you don't have to deal with upsizing the struts. Not even sure you can find monel these days.

I have monel shafts...
Monel shafts are on par with A22, but are much more fatigue proof making them superior in one way but they do not handle torque as well.
I wouldn't run 1-1/4" monel in place of 1-3/8 A-22 for diesel applications...maybe ok without reduction on a high revving lower hp motor.


Yes monel can be had but the cost of the material itself is more then the cost of a finished A-22 shaft and it still needs to be straightened and machined. Maybe that offsets cost of going up a strut size...until a shaft is lost. Then a replacement monel shaft has to be made again...hopefully when it happens your at home port as it will take awhile, they can be had, but to my knowledge they are not stocked like A-22.

[Bruce]

https://www.go2marine.com/product/21260 ... ifold.html

[coolair]

I do have 1 3/8 SS shafts. But at this point I have going to have the 460s freshened up, replace a few things like water pumps, fuel pumps, distributors, etc and roll on.
Again the biggest potential expense is the exhaust manifolds. Is there any good way to actually test them? Obviously you could pressure them up with water or air...

Right now my options are going with high dollar aluminum manifold/SS risers for $3000 a set, using an adapter plate and switching to BBC manifolds ranging from $1800 to $2400 depending on what brand adapters and manifolds you use(Hardin and looks like GLM make the adapter plate. Hardin is aluminum and GLM is cast iron), there are possibly some "good" used manifolds available OR the log style Bruce sent the link for.

For sure the logs are the most economical, but i was not sure if they would work in my application. Is the big concern with them water coming up the exhaust if you dont have enough rise?