replacing Mercruiser 4.3 v6 1993 engine with Chevy s10 4.3 v6 1993

[dlogvine]

I started rebuilding heads and found that on one of the original mercruiser heads the valve seats for exhaust valves were very deteriorated, the seats looked very chewed up with a lot of cavities. The intake seats were smooth and clean. Is there way to repair this damage? I can make pictures tomorrow and post. And im surprised that the machine shop did not mention this wear of the valve seats in their inspection. Another finding, one of the broken exhaust manifold screws was left in the hole and the shop did not bother to remove it. Will take these heads back to the shop tomorrow for some explanations.

 

[Rick Stephens]

What was done by the machine shop? If I had heads done I would expect them to look great when I got them back.

 

[dlogvine]

What was done by the machine shop? If I had heads done I would expect them to look great when I got them back.

The heads were cleaned and the shop manager gave me repair estimates. However, when I looked at the heads, one had a broken bolt sitting in and on the other one the seats of the exhaust valves were all very deteriorated with a serious cavities on the sides of the valve wells. I'm not sure if this head is salvageable.

 

[Rick Stephens]

The heads were cleaned and the shop manager gave me repair estimates. However, when I looked at the heads, one had a broken bolt sitting in and on the other one the seats of the exhaust valves were all very deteriorated with a serious cavities on the sides of the valve wells. I'm not sure if this head is salvageable.

So all they did was tank em and write an estimate... I wouldn't have expected them to pull a broken bolt as part of that process. Without seeing really well how bad the exhaust seats are there is no way to have an opinion on repairability.

 

[dlogvine]

Actually the shop did a little more, they took out all the valves and checked the springs. Kind of suspiciously, but all the springs in both sets of heads according to the shop were weak and needed replacement. Even though the marine engine had only 250 hours of work and chevy engine had at least 120K miles. But I bought a set of Mercruiser heads, one in perfect condition, in the other one exhaust valve was damaged and it did damage the seat. I'll have to make pictures of them all when I get back home in a couple days. I understand it is impossible to make any diagnosis without a good picture.

 

[dlogvine]

I wondered if I can use different heads on the same engine, both heads are for 4.3 v6, however they have some differences in the rocker bolts design, on one of them these bolts are solidly inserted in the head, on the other the bolts are removable, later version. Worst case scenario, I found a pair of newer heads from 2001 chevy vortex engine. Looks like they are in a great condition and I could get both of them for $50 or so.

 

[Bondo]

I wondered if I can use different heads on the same engine,

Ayuh,..... You should always use matchin' Castin' Numbers,...

I found a pair of newer heads from 2001 chevy vortex engine. Looks like they are in a great condition and I could get both of them for $50 or so.

That's a Very good deal, if they're in good shape, 'n dressed...

 

[dlogvine]

No Title

got a pair of heads from 2001 chevy 4.3 v6 vortex engine and then the guy showed me the block, dirty but with nice cylinders and not seized, from the force required to crank the engine with removed heads and exhaust manifold and according to the owner, looks like the engine is in decent condition. will rearing it, change the bearings and gaskets and timing gears. Just need to find an intake manifold and will get a nice engine.
as for the old heads with corroded water damaged seats, looks like they are repairable, inserts could be sleeved in and replace the old seats. and it is not too expensive, in a range of $25- $45 per head

 

[dlogvine]

No Title

second head from mercruiser 4.3l v6, original one. exhaust valve seats are water damaged