Engine: Oil Leaking Into Crank Pulley

[Studeguy61]

I have a 1958 289 engine. I have replaced the timing cover gasket, crank seal, and gooped the keyway and bolt and when the engine is run at speed the oil will collect in the lower crank pulley. I thought it must have been seeping by the bolt, but think the last time I really sealed it. It does not leak at idle, only when at operating speed. The front and bottom of the timing cover are dry of oil. It does not seem to be the crank seal. I am at a loss as to what can be causing the leak. Any suggestions will be greatly appreciated. Thank you.

[WinM1895]

IMO, the timing cover seal is leaking and as I recall, the original was made of felt and this was a very common occurrence.

[skyway]

I can't figure out where oil would "collect in the lower crank pully?" Can you describe in more detail? Until then here are some thoughts.
Bascially, the big center crank bolt should not leak oil because it is a blind hole and serves only to fasten the hub, damper and pullies. Also, the hub and keyway should be assembled without lube (or "goop"), again those should not leak oil.
The more typical leaks are caused by a bad felt washer in the timing cover, or when the lower timing cover bolts become loose because the threads in the aluminum filler block have stripped. The usual fix/improvement in these is, (1)with the timing cover off the engine to drill a small hole in the bottom backside of the sheetmetal collar that holds the felt seal. This allows oil from the saturated felt to drain back into the crankcase instead of seeping out the front of the timing cover; and
(2) Repair the stripped out filler block. Options here are either helicoil the bolt holes, or to simply drill all the way thru the filler block and then install bolts with their heads on the backside and their threads (long enough to go) out the front of the timing cover. You then use liquid steel to epoxy the bolt heads (and the threads inside the block) in place with their bare threads acting as studs protruding out thru the lower timing cover. Finally, always leave the timing cover loose until you have installed the crank shaft hub. That way the hub and cover can find their own centers.
Again, just my thoughts. Good luck.

[Alan]

I have taken apart some engines that guys said leaked oil and some if not all were missing the thick cup shaped washer I call an oil slinger.

[altair]

The fuel pump is very close check that it is not leaking

[WCP]

As Alan pointed out, it is important that the oil slinger is in place, but also that the pulley hub is fully bottomed and torqued to specification against that oil slinger, to minimize oil seepage along the keyway.

[warrlaw1]

I thought I'd have to replace the seals in my timing cover only to find out that the bolts holding the cover had managed to come loose all by themselves. Good luck.

[Studeguy61]

Here is some additional info. I can rub a paper towel on the front of the timing cover and the bottom of it and there does not seem to be any fresh oil in either area. That would seem to me to eliminate those 2 areas. I also checked the timing cover bolts and they are tight. I also thought the crank hole was a dead area with no oil. I can not think of any other place the oil could be coming from to end up in the lower pulley. It is interesting that it does not leak at idle, only when driven. I drove it about 50 miles today and rechecked all the areas and no fresh oil except in the lower pulley. I also checked the PCV system to ensure that was not clogged. There is not any oil coming from the fuel pump either. Very puzzling.

[WCP]

Reread post #6. The oil is coming thru the keyway in the crank hub.

I smear a coating of "Hylomar" on the inside face of the crank hub that presses against the oil slinger to minimize this oil seepage. A thin sealing washer at this location would have been a better design approach. Make sure that the crank bolt is torqued adequately. If there is any gap, even .001", between the inner end of the hub and the slinger or thrust washer (if the slinger is missing), then the seepage thru the keyway will be significant.

[woodysrods]

Serious shot in the dark here, but is your car an automatic? Are you sure it is engine oil on your pulley or could the trans lines into the lower rad tank have a leak??
Just a thought??
Good Roads
Brian

[Studeguy61]

Thanks WCP. I will be taking it apart the first of January and will use your suggestions. I torques the bolt to 140 ft/lbs last time, but your theory seems to make a lot of sense. Thanks, I appreciate everyones idea.

[Paul Keller]

Note that Permatex is now selling "Hylomar" in tubes for the auto market - It is marked as being fuel and oil safe and has the Hylomar name in the upper corner. Do not have to buy the $100 industrial size any more (got mine @ Kragen/OReilly or Auto Zone, don't recall which).
Paul TK