Help with year range 4.3L

[CatriderF7]

I need a new block for a 91 sea Ray with a 4.3L. Im planning on buying an engine from a blazer, s10 or astrovan. I remember that it needs to be newer than 85 or 86 or my flywheel won't fit, and it can't be a balance shaft engine because my intake won't fit on it. What year did the balance shafts start?

 

[Bondo]

Ayuh,... I believe it was '92, possibly '93,....

I also believe the intake manifold don't care either way,....

The timin' cover changed, don't think the intake did,....

That said, I believe any 4.3l from '86, to '95 will work for ya, with at worse addin' an electric fuel pump,.....

 

[Fun Times]

Here's a guide with some small notes covering some of the changes done over the years, MerCruiser GM Engine Code Identification - Marine ?

 

[Rick Stephens]

Hard part is the fuel pump gets blocked off on later blocks ('92 I think) and you end having to put an electric pump on. Don't worry about the balance shaft. You can run standard timing chain set even in a balance shaft block (leaving out the balance shaft) and only have to have the front cover. Note, the front covers are a lot nicer for the pre-balance shaft. Metal and reusable. The balance shaft cover is plastic and disposable.

It is not a huge deal to drop a later model Vortec engine in. You would definitely need to add an electric fuel pump. Nice horsy power increase.

Rick

 

[CatriderF7]

Thanks for the info guys. Reason I am wanting a non balance shaft engine is because the last one I did had a balance shaft and my intake wouldnt clear it, I think I ended up having to buy a different intake, and remove the gear that drives the shaft so it wasn't spinning anymore in order to get the intake on. Maybe I will look into putting a newer vortec in it. Theres tons of them around for around $400 or so

 

[bruceb58]

Definitely get a newer engine with a Vortec and change the intake. You will also be able to find an engine that hasn't been sitting around as long and also find one with less miles.