Quick ? oil gallery plug

I thought I might chime in on this one.

I went through a similar problem on my '36 LB engine earlier this year. Just before first startup, with the spark plugs out I spun the engine over on 12v to check for oil pressure using an analog gauge. I got zero pressure this way. So off came the intake manifold, the pressure relief valve was intact, and no oil was flowing out the hole on the bottom of the clutch/flywheel area of the pan, so the only thing left was the front galley plug (or a dud rebuilt oil pump)?? I removed the distributor cover, and drilled a small hole in the timing gear about where the plug should have been and lo and behold NO PLUG. After installing the plug (and a certain amount of swearing later) the engine had something like 30-40 psi oil pressure at idle.

I am very glad I resisted the temptation to 'just start'er up and run it a while' to see what would happen. Those connecting rod bearings were very hard to come by in that engine!
 
I've often wondered why the plug on the left was used to restrict flow to the relief valve. On several occasions I have used a plain plug (Right) and saw no differance in pressure. ??????
 
I've wondered the same. There is a bit of info on the changeover to the extended plug in the bulletins, but as I remember it clarified nothing. I'll try to lookitup again.
Somewhere in the '32-37 bulletins I think.
Folkloric/speculative info on plug and pressure: A friend bought a good running but high mileage late Merc, which had distreesingly low pressure. Little when cold, would just tickle the gauge to move visibly when hot...naturally, he found plug missing, so the things are at least capable of producing SOME pressure AND keeping the engine alive without the front plug. It seems to be at least conceivable that a nice tight new engine with an excellent pump might be able to show 15. Especially if pump is high volume type.
The myths about the pushrod hole have filled an unbelievable amount of space on the barn over the years...countless electrons have died in vain, with many left in darkness.
 
I know this is an old thread, but how do you get those stubborn plugs out? I've ruined two big screwdrivers... in there a straight blade for a small impact?
 
There is the hammer activated hand held impact generally used for the stubborn screws on motorcycle engine cases. They are good to have around if you don't have one. The hammer hit first gives a nice hit to shock the screw, and then the handle twists to break it loose. They use the small hex tool bits, but could be adapted up to 3/8 drive and then grind a bit to fit
 
Try Third Gen Auto in Tenn. for the correct front plug, I believe they are reproduced. The additional length controls oil flow to the timing gears and the rear of the distributor.
 
Well, I hope I don't need a plug. Just hoping to get mine out without damaging it. I'll try my trusty heat and candle wax.
 
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