Distributor Questions on 346 engines

[vicbrincat]

I am installing a rebuilt distributor and distributor  tower back on my '48 motor.

I have several gaskets sets but none of them specify which gaskets (if any) are for the distributor.

First of all there were no distributor gaskets on my original setup..that would probably explain all the oil that covered the engine and firewall when I first got the car.

I assume there is a thin, (non cork) gasket between the base of the distributor tower and the block itself. This gasket can't be too thick as it may hamper the alignment of the distributor gear and the idler gear. Non of the kits have the gasket..no problem..I can make one out of thin gasket material...(about thickness of a cereal box carton).

Secondly, is there a gasket between the distributor "Head" and the top of the tower? I would think there would have to be ..otherwise oil may seep out?
The gasket set have a cork gasket that is just the right size to fit between the head and the tower. But the cork gasket  is about 1/8" thick. I am concerned that it won't allow the distributor shaft and the distributor head to mate  appropriately.

What has everyone else done here?

Any thought from experienced flat-re builders?

Vic

[Tod - NTCLC]

Vic -

Thanks for asking these questions - I just finished painting my distributor tower and the distributor, and I have the exact same quandry.  When I removed the parts, there was no gasket at the block, and there wasn't one where the distributor bolts to the tower either and I don't see these gaskets listed as parts of any kits.  I also read back thru Walt's rebuild guide, and didn't see a reference to these gaskets.  I am wondering if a smear of RTV on the tower base would be a good idea since this bolted down and not subject to adjustment.

Let's hope that one of the flathead pros sees this and gives us the verdict.

[Bill Ingler #7799]

Below is a response I found using search from Tom Beaver to a similar question about oil leaking from the distibutor tower. I also can find no gasket in the master parts book for use between the base of the distibutor tower and the block nor one between the base of the distributor and the top of the tower. The key to stopping a oil leak is to make sure the drain hole is clear.

« Reply #1 on: September 20, 2009, 05:33:50 am » Reply with quote 

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The distributor shaft bearing located in the tower that bolts to the block is lubricated with engine oil and seepage past the bearing is supposed to drain back into the block by a hole and passage cast into the base of the distributor tower.  If that hole or passage becomes blocked by buildup of sludge then oil can back up and fill the distributor tower all the way up to the distributor itself, which may be what you are seeing.  If that is the case, pull the distributor and distributor tower and clean them all up making sure the drain passage is open and that you don't have excessive clearance between the distributor shaft and bearing and then reinstall.  That should fix the problem.  Good luck.

Tom Beaver

[vicbrincat]

Thanks folks,

based on Tom and Bill's  answer it makes a lot of sense that none of the kits actually have a distributor  gasket.

Now here's the funny thing: Coopers (in California -  who in my opinion is one of the most reliable suppliers) lists a distributor gasket (cost $1.00). I order a couple and what I got was a round cork gasket...not 100% where it would go.

Based on Tom's finding I am not going to use one...simply because the spacing on the distributor is absolutely critical  to these motors...(I envision horror stories of damaged idler gears if the system is not perfectly aligned).

With regards, to the RTV silicon....that sounds like a good idea...and I will probably go that route...BUT make sure not to use too much. You don't want it oozing back into the block or blocking the drilled oil passages/drain holes  in the distributor tower base.

[Bob Schuman]

Vic,
In over 45000 miles with my 41, with no gasket between the distributor and the tower, it has never leaked oil there. What has been said about the tower oil passages being open is critical. Where the tower bolts to the block, use either a very thin paper gasket(about .006 inch) or preferably RTV gasket maker, available at any auto parts store. Just put a thin film on the mating surface, so that there is no excess to possibly get into the oil holes. In a recent conversation with Jerry Steelman, who sells the complete kit to correct problems with the idler gear, oil pump, tower shaft, and distributor, Jerry told me a thick gasket under the tower will cause improper alignment of the bronze idler gear and the gear on the tower shaft. He recommended using RTV instead of a gasket.
One word of caution-I recently installed mine with RTV, and the instructions said to assemble parts immediately. I did that, but had it one tooth off of correct timing, and had to lift the tower one hour later to correct the timing. The RTV, which worked fine on another car, did not reseal. I'm going to have to pull the tower, remove the RTV, and reassemble with a new application of RTV.
Bob Schuman

[vicbrincat]

Excellent point about the base gasket.

Chances are, I will need to adjust for tooth mis- alignment.

Not to change subjects ...but I too did lots and lots of research on the idler gear issues.
I had the distributor shaft bushings rebuilt because mine had a lot of slop. I also managed to get an oil pump with spiral gears...my spare engine had one  was barely worn. I had the pump tested and measured for wear. The idler gear in my car also has minimal wear, as does my spare engine. All this combined with the ZDDP in the oil  that I will be using on a regular basis should give me many miles on this rebuild.

I'll keep my fingers crossed.

Thanks again for the input.