Dry cams

[techweenie]

I can hardly believe the saga of my friend's engine. It was seized from sitting. He broke it loose with Marvel Mystery Oil and patience. Then it wouldn't start because of an internal short in the distributor. Then it wouldn't run on al 6 because of stuck injectors and MFI pump.

One by one, these problems have been revealed and addressed, but now, with it running okay, the lower valve covers were dropped for a valve adjustment and it appears the cams aren't getting oil. Some lobes are dry.

The cause isn't directly obvious, but a clue is that the lower valve covers were sealed with a lot of silicone.

If silicone has broken loose and travelled the oil passages, is there any solution other than complete teardown?

[Grady Clay]

Rube Goldberg at your service.


How about a simple idea. Get a small pump-up bug sprayer from the local home supply and adapt the flex cam oil hose to it. With the valve covers off, pump up the sprayer with engine oil in it. See which cam oiling spray bar ports are blocked. Try getting whatever out with some fine wire while the oil is flowing.

Or

Is it too late and the cam is damaged?

Best,
Grady

[DW SD]

Grady,
Clever!!

Doug

[techweenie]

Originally posted by Grady Clay
Rube Goldberg at your service.


How about a simple idea. Get a small pump-up bug sprayer from the local home supply and adapt the flex cam oil hose to it. With the valve covers off, pump up the sprayer with engine oil in it. See which cam oiling spray bar ports are blocked. Try getting whatever out with some fine wire while the oil is flowing.

Or

Is it too late and the cam is damaged?

Best,
Grady

Me likey. The owner is a contractor, so has the tools & ingenuity.

The cams are not damaged. They haven't been run but for a few minutes in years.

[aigel]

You can suck on the cam line too, to get the silicone out of the cam oilers.

George

[techweenie]

Originally posted by aigel
You can suck on the cam line too, to get the silicone out of the cam oilers.

George

Probably best not to swallow, though, eh?

[Zeke]

Originally posted by techweenie
Probably best not to swallow, though, eh?

Ouch! Well, if there is one bit of silicone, there just might be more somewhere. I think I'd start on the tear down (to a certain point, anyway). My thesis here is that the problem was introduced further down in the system and reached an extremity. Where is the next one to get caught?

[aigel]

So, can someone elaborate how the silicone gets into the cam spray bar past the oil filter?

G

[DW SD]

Originally posted by aigel
So, can someone elaborate how the silicone gets into the cam spray bar past the oil filter?

G

G-
Depends where the silicon is and where (else) it was used?

If it comes from the valve covers then it could makes its way back in through the pressure relief system on the scavenge oil system. Seems unlikely.

OR if it comes from somewhere else..... (as you know) oil is filtered on its way back into the oil tank after thermostat, not on the way into the inlet side of the pressure pump (fed by S-oil line).

Doug

[aigel]

Good point. There may be more silicone. But if it is just on the valve cover, it's hard to see how it gets to the pressure side of the oiling system.

Techweenie,

I am surprised that your pal did not just take the engine apart in the first place. I'd be scared to start such an engine without tearing it down. But I suppose he is trying his luck ?

George