4.3 Valve seals

[SeaRayboater95]

Hey Guys and Gals:

Was going to change the seals on 1996 Mercruiser 4.3 and automotive says they discontinued. Local Merc dealer wants over $250.00 for said seals. There is a little square O ring on the top of the valve that wont let the valve go past the seal. Thinking of just taking the valve out, cleaning it up and lapping it and putting it back in. That O ring on the top of the valve doesn't really seem to have a purpose. Worried about damaging it getting it out. Need a bit of help here, please.
Are these seals marine specific, or can I get them some where else.

Ken

 

[alldodge]

@Scott Danforth

 

[Lou C]

I can't imagine they are marine specific. The heads are just plain old Chevy V6 heads. Take the casting # off the head and go to a GM dealer! Merc loves to charge an absurd surcharge for a part GM made and is available in the aftermarket as well. Do not buy any GM engine parts from either Merc or Volvo they are just crooks! Look on Jegs, or Summit Racing, see if you can figure out the production year range of the engine from the block casting #; which is on the part of the block that is behind the cylinder head, I think on the starboard or passenger side if in a vehicle.

here you go, this is the later model Vortec style but the older Pre-Vortec which is what I think you have, should be similar.

 

[Lou C]

Part Details

www.drivparts.com

this is from Fel-Pro, I used 1995 as a model year because the one you're working on is a pre-Vortec, the true Vortec came online in 1996, and they supposedly fit from 1986-1995, so it might be the right seal.
I used their marine head gaskets and intake gaskets on my top end overhaul and they both sealed well.
BTW since it's raw water cooled you have to use marine style head gaskets.

 

[Scott Danforth]

Felpro and Mahle both sell seals and gaskets every day, nearly everywhere

If your motor has 8 intake manifold bolts, the motor is a 1996 to 2003 4.3

If your motor has 12 intake bolts , the motor is a 1993-1995

Just look up parts for an S-10 truck

 

[alldodge]

Felpro and Mahle both sell seals and gaskets every day, nearly everywhere

If your motor has 8 intake manifold bolts, the motor is a 1996 to 2003 4.3

If your motor has 12 intake bolts , the motor is a 1993-1995

Just look up parts for an S-10 truck

Scott, reason to mention you is it looks like it has 2 different type seals and have not seen the multi seal ones

 

[Scott Danforth]

Head has had work done prior. The valve guide on right is stock, on left has been cut and a different seal

 

[SeaRayboater95]

Head has had work done prior. The valve guide on right is stock, on left has been cut and a different seal

Thanks for that. Never a dull moment in this project. I'll pull a couple more and see what I find. Can I clean the valves and lap them with the seals in? In leak down, the valve were showing some leaking. The seals themselves really weren't that bad. Thought I'd just change them while I had the heads off. Nothing is ever easy or cheap when it comes boats.

Ken

 

[nola mike]

Thanks for that. Never a dull moment in this project. I'll pull a couple more and see what I find. Can I clean the valves and lap them with the seals in? In leak down, the valve were showing some leaking. The seals themselves really weren't that bad. Thought I'd just change them while I had the heads off. Nothing is ever easy or cheap when it comes boats.

Ken

This engine is as easy and cheap as it gets