Where can I get replacement oil passage plugs for my crankshaft? The machinest said he did not remove them after grinding because he had no replacement plugs. I believe they should be removed to properly clean out the oil passages after regrinding. Is removing and replacing the plugs something I can do myself?
First 356 engine rebuild

Thanks

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Hi Richard
This is a job best left to specialist. I would suspect your crank is not ground properly if your vendor is not capable of addressing the plugs. The plugs will loosen if the crank is Nitrided which should be done on late cranks. Aftermarket cranks like Scat have threaded replaceable plugs you can do the same on your crank. Porsche crank grinding and hardening is not a generic operation. Most of the major European car manufacturers do not even offer undersize bearings now in an effort to preclude less than optimal repairs. I am not trying to fault your efforts to restore your car you can just clean the crank witout removing the plugs and if you are lucky get good service from your overhaul. But if it were my crank i would get a second opinion.
jacques

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thanks for the reply.
The guy has been grinding cranks for 30 years and said he did a lot ove the vw in the 17-80's but now does diesel cranks. he did mine and it mikes out perfect but he has no plugs to replace with old so he did not remove the old ones. I will find a shop that can replace the plugs and make sure the passages are clean.

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Years ago I made a special tube w/small angled holes in its end to fit the inter-drillings to flush and blast clean w/air; I still use it if the crank doesn't need a regrind by CCR in CA.
Never had a problem--even w/the older non-plugged cranks.

Dick

This is not a job for an owner with a limited tool selection. What's needed is a good number/letter drill set, a small engine lathe, a micrometer, and a set of pin gages graduated in .001 in. Take a small center punch and make a punch in the center of the crank plug, check carefully that it's on center. Start with a small drill bit and drill the plug, this is a good time to correct slight off center punching by angling the drill. Hole must be drilled at an angle to meet the exit hole thru crank web. Gradually increase the drill size and you'll get to a point where the drill bit will "bite" the plug and spin it out. Do this to all the plugs. Clean with a small brush and solvent. Might have to pick thru the crud as it's packed in good. Blow clean with compressed air. Get a measurement of the hole to the thousandth. Make a plug on the lathe the same length from some aluminum bar stock purchased at the local hardware store. Plug should be .005 diameter bigger than the hole and tapered for half the length of the plug down to .001 smaller than the hole size. I use a mill file to put the taper in while on the lathe before parting the plug. Using a punch the same size or slightly larger than the plug pound plug into crank. Plug should go in with a good amount of resistance, hammer in flush. I've used this method for many years with no failures.

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Great advice, will pass along to the machinist.

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Please explain why the crank hole needs to be plugged. What if the hole is not plugged? What would happen???

TIA,
Alan

Alan,
The plugs close the ends of the drilled cross-holes and keep the oil flowing to the bearings. Absent the plugs, the oil would pour out the 'ends' of the journals and the bearings would get no lubrication.

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Ron,
If the plugs were missing, would you have low oil pressure while running?

TIA,
Alan

Oil pressure would be somewhere between little and none, leaning toward the "none" side.

Cheers,
Wes

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