GM V8 repower

[welshswampy]

Hi all, would a GM 6.2l diesel fit in the same engine bay as an OMC 5.7l petrol?
If so, how much heavier is the diesel compared to the petrol?
Also your thoughts on the above change?
Is the block the same on the both engines, ie are they the same GM based engines
Thanks Nick

[bondo]

Ayuh,... The 6.2 diesel shares pretty much Nothing with the 5.7 gasser....

The 6.2 has been used as a boat motor though...
It's closer to the BBC...

[welshswampy]

Dont know what BBC is or what it stands for
Just wanted to know if the weight and physical size were similar to determine if it would be feasible to swap, also wondered if the blocks were the same(just out of curiosity as they are both gm based)
Regards Nick

[bondo]

Dont know what BBC is or what it stands for
Just wanted to know if the weight and physical size were similar to determine if it would be feasible to swap, also wondered if the blocks were the same(just out of curiosity as they are both gm based)
Regards Nick

Ayuh,... BBC = Big Block Chevy.....

No, not the same,... slightly longer, 'n wider... though motorbox size isn't the issue...
weight, I'd guess at 100 to 200 more...

[welshswampy]

Thanks Bondo, I assume you mean 100 to 200lb's, if thats the case then its gunna be too heavy
Cheers anyway, Nick

[bondo]

Ayuh,... yes, pounds Nick...

Good luck with yer project....

Bein' a Diesel kinda guy myself, here in the States, an Easy diesel swap just ain't in the cards....
I've looked into the GM 6.2, 'n the Navistar/ Ford 7.3s,....
Neither is cheap, nor easy....

[welshswampy]

Picked up a GM v8 diesel and a VP 290 DP a few days ago, this one has cast aluminium manis and risers, so is only about 30/40 Kilos heavier overall than the petrol engine, so I'm gonna give it a go
Will post at various stages of the project ( just so you can all thank the lord that its not you in my shoes)
Regards Nick

[Reverend Bob]

( just so you can all thank the lord that its not you in my shoes)
Regards Nick

I do everyday, especially with what they charge you for fuel over there!

[welshswampy]

any one know the torque setting for a gm v8 6.2l diesel big end bearings

[welshswampy]

Anyone tell me the procedure for fitting a replacement engine and transom plate
Does the transom plate get fitted first, then fit the engine to suit?
If so, what height above bottom of boat does the transom plate sit (I havent got a lot of room to play with)

Regards Nick

[welshswampy]

For anyone thats interested repower now complete,the engine went in sweet as a nut on original stringers as did the new transom shield etc, reused a lot of the original OMC parts (trim pump,power steering pump and ram, throttle cable, although gear cable was renewed as it was too short to reach outdrive) needed to make some new brackets for the power steering ram, power steering pump and a bracket for the throttle cable near the fuel pump
Went with 3" thru hull exhausts as I couldnt find the "Y" exhaust pipe over here, also had read about possible back pressure issues with these engines/Y exhausts
All in all it was a sucessful project, and one I could recommend
The boat doesnt sit any lower in the water whatsoever ( think this is due to using the alliminium manis and risers and reducing the size of the fuel tank)
My biggest problem is reshaping the engine cover that had to be cut on the sides to accomodate the risers and the front to miss the power steering pump and heat exchanger water pipes, have extended the sides and front using 4mm plyboard which has been glassed in place and now need to be filled,primed and painted
I really wish the painting fairies would pay me a visit overnight !!
Couple of minor issues, dont know which terminal on the alternator to connect the rev counter wire and just connected the gear shift cable straight to the gear linkage on the out drive without checking rotation, now gears are opposite to control lever, can I change this on the throttle control lever linkage? if not it can wait til the boat next comes out of the water
If anyone is interested I can post some photos
Many thanks for all your help/advice
Nick