864 v8

[Jocko]

hey guys im just curious on my 864 v8 it is burning oil through the valve guides would I be able to get custom valve stem seals made for this truck. and would it be worth it.

[theakerstwo]

You need to talk to a shop who rebuilds heads and you may find the seal will be easy to find.But the guides my be worn out also.

[skip]

Ive got a feeling they didnt have seals, I think they used thick o-rings with a cover over them. I thought it was an o-ring similar to a rocker oil feed on a 6 cylinder. How much oil is it burning? If it is not getting used much it will slobber fuel out into the exhaust ports and make a bit of a mess, which can make it look oily. Mine does that if I dont use it for a while. A good run with a load cleans mine right up. Keep it in mind that if you take the heads off it you can open a can of worms. When I did mine up all 4 heads were in good condition with no cracks, but the valves and guides were worn. I probably couldve got away with them as its only a show truck but I had a few parts available at the time so I put new gear in them.

[Bigdogtrucker]

Are gasket sets even made for these?

[theakerstwo]

Ive got a feeling they didnt have seals, I think they used thick o-rings with a cover over them. I thought it was an o-ring similar to a rocker oil feed on a 6 cylinder. How much oil is it burning? If it is not getting used much it will slobber fuel out into the exhaust ports and make a bit of a mess, which can make it look oily. Mine does that if I dont use it for a while. A good run with a load cleans mine right up. Keep it in mind that if you take the heads off it you can open a can of worms. When I did mine up all 4 heads were in good condition with no cracks, but the valves and guides were worn. I probably couldve got away with them as its only a show truck but I had a few parts available at the time so I put new gear in them.

that's right.

[BAD DOG]

I don't think those heads have valve seals either. If it isn't burning oil don't touch it. And if it isn't being used much or really worked ant Mack V8 slobbers fuel out through the split in the exhaust manifolds. Even E9's. it just looks like oil. It's nature of the beast.

[skip]

Bigdogtrucker, parts for those engines are very hard to come by. I was still able to buy head gaskets from Mack USA through the head branch over here up until 2 years ago. Rocker cover gaskets are very hard to find. Exhaust manifiold gaskets were available also, and the intake gaskets are likean 865/6 ad were still available. I made a sump gasket and p/s pump gasket. The rear seal was available, the CR number was the same as a 14 litre Cummins but the sleeve was the problem. So there is the odd thing available, but its getting harder to find. I am looking at making up some gasket sets next year from the stuff Ive got here. It wont be until January or February but Im hoping to have a few sets available if you need.