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5.7L engine swap; need a little information

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sabotage

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Hello all! I have found this site and most post's here to be very helpful. With that said, I am hoping some one here can help me out with some information. I have a 1986 Pursuit Tiara 2200 WA with a 5.7 L GM engine with an Alpha 1 outdrive. Rusted a hole in cylinder number 2 so I am changing the engine with the 5.7L GM out of a 1996 Bayliner Capri that also has an Alpha 1 outdrive. My question is, will this engine bolt up to my 1986 Alpha 1 outdrive using the flywheel and engine coupler from the 1986 5.7L GM engine? I also my have a 1991 5.7L GM engine I can get to put in the place of the original engine. Thanks for any help that you can provide.
 
sabotage said:
Hello all! I have found this site and most post's here to be very helpful. With that said, I am hoping some one here can help me out with some information. I have a 1986 Pursuit Tiara 2200 WA with a 5.7 L GM engine with an Alpha 1 outdrive. Rusted a hole in cylinder number 2 so I am changing the engine with the 5.7L GM out of a 1996 Bayliner Capri that also has an Alpha 1 outdrive. My question is, will this engine bolt up to my 1986 Alpha 1 outdrive using the flywheel and engine coupler from the 1986 5.7L GM engine? I also my have a 1991 5.7L GM engine I can get to put in the place of the original engine. Thanks for any help that you can provide.
Click to expand...

Ayuh,.... It Should drop right in, No problem,....

Only difference I can think of is, ya won't need the drive oil bottle from the '96, as the '86 don't have a remote resivour,...
 
Thanks for the info Bondo! I guess I can get started now, that was the last of the research I needed before I started tearing into it. It will be nice to know there is a younger power plant under the cover. Next stop will be the closed cooling system as I am in saltwater only, probably why the first engine rusted a hole in the cylinder. Looks like the previous owner did not take as good of care of it as he said. He did have the motor rebuilt as he said, I noticed it was bored .060 over, I thought that was a little much for an engine that would be running in salt water. I always figured the more meat around the cylinder walls the better, since this is not a race boat... Any thoughts on boring marine engines? I'm starting to think he had a car engine put in it,I noticed a valve seat missing on number 5 cylinder (intake).
 
Probably not a repair.

The previous owner most likely had a remanufactured motor dropped in. A cheap one that and did not have good quality control, thus the missing valve seat......??? (assembly line production)

Very typical for a engine remanufacture to bore them .060 over.

costs about ~ $2000+ for a long block (remanufactured)
 
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There's one thing here that is being overlooked.
The 1986 engine crankshaft flange is considerably different from that of the 1996 engine crankshaft flange. This means that neither flywheel nor Drive Coupler can be interchanged.
If you question the 1986 Drive Coupler at all, you had better replace it now, rather than chance failure later on!



.
 
So niether will swap out? Is there a replcement or adapter for this type of conversion? Definetly going to inspect all components, I only want to take it apart and put it back together one time, or at least not for a long time again.
 
No........ the engine itself will swap just fine.
The only part that will concern you will be the difference in the flanges at the end of the crankshafts!


Go here and scroll down to the crankshaft flange image.
http://www.hotrodders.com/forum/lt1-148558.html

The flange on the left side is post-1987.
The flange on the right is pre-1987!


.
 
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sabotage said:
So any ideas on what to do?
Click to expand...

Ayuh,... Do ya have both flywheels,..?? '86 was the transition year, it May not be an issue,...

The older crankshaft bolt pattern was 3, 1/4" dia., the newer cranks are 3" diameter,...

Sierra makes/ sells a conversion coupler, for the crankshaft mounted couplers,...
The flywheel mounted couplers will interchange onto both flywheels,...
I think yer's is the crankshaft style, so the Sierra conversion coupler will cure the issue,....
 
Thanks for all the info guy's. I'll be pulling the 86 motor over the next couple of days, will check that everything fits right and get the conversion if needed. Is there anything else I should repair/replace while I have down that far? Already planning on the U-joints and checking the gimbal bearing. Am I missing anything?
 
sabotage said:
..............
Is there anything else I should repair/replace while I have down that far? Already planning on the U-joints and checking the gimbal bearing. Am I missing anything?
Click to expand...
This may help:

A new drive coupler would be imperative, IMO.

Use the correct flywheel for the crankshaft flange, and you won't have any trouble.

168 tooth flywheel requires the staggered bolt pattern starter motor.
153 tooth flywheel requires the straight-a-cross bolt pattern starter motor.

Buy yourself a HTGR/PMGR starter motor, and say goodbye to any non-gear reduction motor.
Make absolutely certain that the starter motor nose housing bolts are of the correct length. (not all housings are the same these days, which may create an issue with bolt lengths)

Now would be the time to install a "remote oil drain hose" in your oil pan!
It would also be an excellent time to install a remote oil filter kit!

After the engine installation, be sure that you go through the Engine drive coupler alignment procedure!
Rent, borrow, build or purchase an alignment tool.


As you are setting up this new engine, be sure to not only check your "base" ignition advance, but also take a good look at the "progressive" and "total advance", as per your OEM specs.
(automotive specs will not work)



.
 
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I guess I'm just anal about "if you have it down this far" I'm gonna tear this motor apart just to make me feel better, dont want to wonder how's it doing when I am 50 miles out as I always take the grand kids. So I have elected to take parts to the machine shop and just make myself feel better before I have to call US Boat to bring us in. If you know what I mean... looks good so far, but I dont want to do this twice, I did find the conversion coupler if needed, still looking for the remote oil change system, which sounds very nice. Thanks for all the info and advice. Please feel free to let me know if there is something I am misding.
 
I have been paying attention to your squish perspective and it makes sense, with the rpm's and the steady running time, I think valve floating and clearence is definetly an issue. Looks like this engine has the double eyebrows tho, so I will be looking to change those along with the cam.
 
Valve float potential would be pretty much limitted to excessive RPM, excessive valve lift and perhaps light valve spring pressure.
A good "Q/E" does not necessarily offer any correlation to this.


Unsolicited advice;

The SBC cylinder head combustion chamber volume must compliment the piston deck, and/or any piston deck dish volume........ and visa-versa.

The GM style full dished piston offers ZERO
quench surface!

Note: actually, there is a very, very small but very ineffective quench surface to this piston.
But due to the dish volume extending out and underneath the cylinder head's "quench surface", it is a lousy choice!


Suggestions for the correct and proper piston for a True SBC Mraine build, will be described in the thread that I linked you to earlier.


.
 
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Gentlemen,
I would like to thank you all for the information you provided, the build is complete and I have had four successful outings. Runs great and I couldn't be happier with the performance, next step is the closed cooling system. I did pick up one from a fella parting out a boat, just need to figure out how this one goes together and where to mount it.
 
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