Valve Gear Oil Supply

CastleMGBV8 · Post by **CastleMGBV8** » Thu Sep 13, 2007 8:14 pm

I have a slight concern that the valve gear on my rebuilt late SD1 3.5 is not getting enough oil to the the rockers and shafts, this was brought about when I was inspecting the Buick 300 heads I recently bought.

On both heads one of the oil feeds was blocked, probably the redundant ones as there is only one oil supply from each block of cylinders, the heads have two oil feed holes to allow the heads to be fitted to either bank of cylinders and therefore ensuring that the rockers get oil.

Now the point is when I rebuilt the engine it was all chemically cleaned but if the heads were fitted in reverse to original then the feeds could possibly be the previously redundant ones and blocked, also I cant remember if I blew them through with the airline.

If they are blocked or restricted do you think it would do any harm to run a bit of stiff wire through them in situ, Im trying to avoid removing the heads especially if there isn't a problem. I thought that if I removed the rocker gear which I would have to do anyway and ran a wire through to clear the oil ways and then turned the engine over with the plugs out, the oil pressure would blow any of the displaced crud back out through the top and get it out of the system.

Any suggestions.

Kevin.

JSF55 · Post by **JSF55** » Thu Sep 13, 2007 10:59 pm

I had the same worry when i fitted mine, i run some brazing rod down there and it picked up a little bit of crap, wot i did notice was that there was quite a bit of resistance as it went through the head gasket, i recon it was out of line a little bit, not something people would necessarily check

ChrisJC · Post by **ChrisJC** » Fri Sep 14, 2007 7:18 am

I would remove the rocker shafts and spark plugs, then spin the engine. If you get a good feed of oil then I'd consider it OK. When I did it, the oil didn't come out fast enough to make a mess...

Chris.

CastleMGBV8 · Post by **CastleMGBV8** » Fri Sep 14, 2007 8:26 am

Thanks guys, I am probably being a bit paranoid but I will feel more comfortable knowing that there is a good supply of oil to the valve gear, my main concern was not to get a lump of crud back into the oiling system and possibly causing a blockage elseware, where it could do more harm.

In theory the oil pressure should push any loosened crud back out through the top of the heads and be caught by a piece of cloth.

Kevin.