PCM 5.8L GT-40 EFI engine - replacement scenario - hints needed

[sharkey74]

Hi,

we have a CC Pro Air Nautique from year 98 with a damaged cylinder/piston, the valve was hanging and knocked against the piston.
Also other cylinders have not the best compressions anymore (the engine ran over 2000 hrs till now, 21 years old), so we see 2 options to fix the engine now:

1) one option would be to find someone in Germany who can remanufacture the engine (with bore cylinders, replace via oversize pistons, etc. )

2) another option would be to order a remanufactured 351W engine with GT-40 heads from US (I saw some vendors at US by searching thru internet)


The engine we have: PCM 5.8L GT-40 EFI (HO Pro-Boss) with 310HP

In case we would run option #2 (by ordering 351W remanufactured engine with GT-40 heads), are there any hints we need to be care so that the parts are fitting together at the end ?

I learned f.e. that there are some differences like:

- GT-40 or GT40P heads, may different bolts of 7/16 or 1/2
- roller camshaft ( I believe GT-40 engine even have roller camshafts ? )
- have GT-40 heads even the holes for the EFI-injectors?

It would be great if you share your experiences on that so that we not run into some basic issues.

Many thanks, Oliver

[charlesml3]

Have someone pull the heads off and inspect the damage. If it's repairable, I would most certainly go that way. Those engines are not difficult to rebuild.

-Charles

[MrJake]

Hi,

we have a CC Pro Air Nautique from year 98 with a damaged cylinder/piston, the valve was hanging and knocked against the piston.
Also other cylinders have not the best compressions anymore (the engine ran over 2000 hrs till now, 21 years old), so we see 2 options to fix the engine now:

1) one option would be to find someone in Germany who can remanufacture the engine (with bore cylinders, replace via oversize pistons, etc. )

2) another option would be to order a remanufactured 351W engine with GT-40 heads from US (I saw some vendors at US by searching thru internet)


The engine we have: PCM 5.8L GT-40 EFI (HO Pro-Boss) with 310HP

In case we would run option #2 (by ordering 351W remanufactured engine with GT-40 heads), are there any hints we need to be care so that the parts are fitting together at the end ?

I learned f.e. that there are some differences like:

- GT-40 or GT40P heads, may different bolts of 7/16 or 1/2
- roller camshaft ( I believe GT-40 engine even have roller camshafts ? )
- have GT-40 heads even the holes for the EFI-injectors?

It would be great if you share your experiences on that so that we not run into some basic issues.

Many thanks, Oliver

Hey Oliver:
Sorry to hear about the motor.

If you do need to order a motor, I’ve ordered 2 motors from Rapido Marine (https://www.rapidomarine.com/ ) and haven’t had a lick of problem with either one of them.

I had one mechanic once say that the inside of one of the motors looked horrible, like it was used as an anchor but both motors have worked flawlessly for me.

Doug






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