Marine engine origins?

[realslimshady]

I may be mistaken here, but my understanding is that some or all of the Mercruiser and Volvo Penta engines are based on old american (GM) mechanicals.
If this is the case (and I know my 3.0l mercruiser is because it has GM and a part number forged into the cylinder head), does anyone know the automotive equivalent to the marine lineup?
I ask because there has got to be some commonality of parts, in the basic mechanicals, I would have thought?
Specifically, in my case, I am overhauling the cylinder head, and Mercruiser stiff nuts that hold/adjust the rocker arms are £4.xx plus VAT <span style="color:#FF0040">EACH</span>....more than the valve springs!!! Come on-aircraft spares don't cost that much!
I bet if I went to an american auto supply place and asked for the same part for a Chevy Impala or somesuch I wouldn't be looking at a £50 bill.....I'd certainly like to find out!

 

[Its_Only_Money]

4.3 V6, 5.7 and 7.4/8.1 V8s are GM based, the 5.0 V8 is a Ford unit I believe.

Try a US based Volvo dealer, you should get the correct bits and probably save on small/light bits that don´t cost too much in shipping... biggest issue would probably be matching the age of the units.

Some (many) of the components are marine-specific, some in the engine core (core plugs come to mind for example to cope with exposure to salt water), and of course the ancillaries are marine specific due to the ignition-protection.

 

[[2068]]

Current Merc / Volvo petrol units are all based on GM blocks. Not old versions, they are all current versions.

As an example, 5.0 HERE.

 

[Scarron]

The 3.0l mercruiser/ 3.0GL Volvo are both the same block which is I believe half a small block Chevy motor. You could definitely get hold of common parts like head nuts elsewhere These guys may be able to help and if you post a message here this Stateside forum may also be useful.

Hope this helps

Paul

 

[longjohnsilver]

Can all get confusing,IIRC some Perkins had Peugeot origins, some Volvos had perkins origins, Yanmars Toyota origins etc etc.

 

[tinkicker0]

The Merc / VP 3.0l is based on the chevrolet 2.5 ltr Iron Duke motor fitted in the Chevy Camaro and such like.

Alternatively you could try purveyors of industrial engines, where the 3.0l is known as the 3.0 Vortec.

Note that cams, pistons, carb, manifolds, alternator, starter, waterpump, fuel pump, various plugs and the head gasket are all marine specific on the Mercury variant.