Front cam cover oil leak on SBC 350 Mercruiser

[SeattleMatt]

Since I installed a remanufactured engine I've been having a difficult time with an oil leak on the front of the engine behind the harmonic balancer. It drips about 1 drip per 2 seconds.

The original engine had a plastic timing cover which didn't fit the remanufactured one so I went out and bought a shiny cheapo one for $17 with included seal. I followed the leak with my fingers and It seems to be coming from the oil seal. I've been working on this problem for quite some time, here is what I have done so far.

I've replaced the seal 3 times, sanded the seal surface on the balancer (600) and added an speedi-sleeve, seal still leaks.

My next idea is to install another new timing cover with seal, but I fear it will still leak. I'm out of ideas and frustrated, any idea what I am doing wrong?

 

[John_S]

Re: Front cam cover oil leak on SBC 350 Mercruiser

In a boat, it is hard to get a good seal between oil pan and timing cover. Dropping the front of the pan is not easy. On a cam change, I had a leak on my 1st attempt. 2nd attempt went fine using more gray rtv in corners.

The balancers changed with the timing cover, but wouldn't think that the seal surface diameter would have??? No, doubt that. I would do some extensive wiping and inspection via mirrors.

 

[odie241]

Re: Front cam cover oil leak on SBC 350 Mercruiser

Those cheap chrome timing covers have always given me a problem leaking.You might try the ol valve cover trick,and hammer down the bolt holes,thats if its leaking between the block and the cover,if not,then hopefully the crank isnt bad where the seals slides through,they do make a sleave kit for those cranks,but its a shame if you have to use one on a reman engine.

 

[SeattleMatt]

Re: Front cam cover oil leak on SBC 350 Mercruiser

I'm not sure I understand the "ol valve cover trick" can you explain further?

 

[EddiePetty]

Re: Front cam cover oil leak on SBC 350 Mercruiser

I'm not sure I understand the "ol valve cover trick" can you explain further?

..The 'ol valve cover trick' consisted of placing an appropriate sized socket over each bolt hole (bolt removed) and gently nuring the distorted flange material back to parallel to its mating surface.

IRT the seal leak: The seal bore in the cover may be a hair off center. Try loosing all of the bolts (including the forward corner bolts on the oil pan), remove the dampener, hi-spot blue the sealing area, install the dampener and check the blue impression. You may have to enlarge the two dowel holes to shift the timing cover to a position that gives equal blue contact.

 

[funk6294]

Re: Front cam cover oil leak on SBC 350 Mercruiser

Make sure you installed the timing cover to oil pan rubber gasket correctly. Double check which side of the pan rail gaskets you have the rubber seal on... The pan rail gaskets should be underneath the lip on the rubber seal, not over it. In other words it should go if looking from the front of the block, engine oil pan rail, cork pan rail gasket, then the rubber cam cover to pan gasket, then the oil pan.

 

[John_S]

Re: Front cam cover oil leak on SBC 350 Mercruiser

from the front of the block, engine oil pan rail, cork pan rail gasket, then the rubber cam cover to pan gasket, then the oil pan.

He should have the one piece oil pan gasket made from rubber, not the old cork gaskets.

 

[funk6294]

Re: Front cam cover oil leak on SBC 350 Mercruiser

Sorry, douple post...

 

[6meter]

Re: Front cam cover oil leak on SBC 350 Mercruiser

The only way to put the timing cover on with the oil pan on is to cut the inner pan seal channel lip on the cover at 45*. Tough to explain and don't know where a picture would be. Gaskets in place, but no front seal yet, plenty of RTV at the pan/block corner, and with 2 dowel punches through the timing cover bolt holes and into the bolt holes in the block, pry down the cover with the punches while tapping the cover in and down. Install seal. If you tried to put the cover on with the seal already in it, you ruined it. The cover being aftermarket, more than likely isn't a very good replica. If the pin/guide holes are off 1/16", it will leak. Go get a used Chevy one.

 

[Kainon]

Re: Front cam cover oil leak on SBC 350 Mercruiser

His problem is around the Damper, crank shaft seal, and he sleeved the damper already. the only thing I can futher think of is checking it dry, and using a little used oil on the seal when installing.

The outer lip seals dirt from the outside and the inner lip seals from the inside. I may be temped to try some RTV at the base of the seal to timing cover surface...