Crankshaft rear core plug depth

[tnova]

When removing the pilot bearing the jaws on my tool grabbed the plug in the rear of the crankshaft and pulled it too. (Yah, I know, operator error.) I don't have access to tool J-38837 and have spent hours on the forum searching past posts on the plug but can't find any spec on the depth to set the plug to. It's not in the 1990-1993 LT5 Service Manual Supplement either.


Does anyone have the depth from the face of the crankshaft rear face to set the plug depth and is that depth to the bottom of the plug concave surface or is it the edge?


If someone has tool J-38837 could they measure the dimensions with a pic and I can turn one on a mini lathe.


Expecting the new plug from Jerry's this week.


Thanks,
Tony - Tnova '91 1773

[Jitse]

Hi Tony,

The depth from the face of the crankshaft to bottom of plug, measured on two different 90 cranks 40.5mm and 40.9mm.

Regards,
Jitse

[tnova]

Thanks. Now I know that the core plug is pressed just inside the bore with the rim even with the step of the oil gallery bore. This adds up to previous posts with measurements on the crank bore, as found indications in my crankshaft end, and measurements from the old core plug. I just want to make sure that without the special tool I was putting it in far enough but not to far to block the hole leading to the bearing surfaces.


Let me thank the following for all their posts on the pilot bearing and core plug: Paul, Dynomite, Jerry, Marc, CcMano, Jss06c6, Jagdpanzer, Demps, Phil, and many, many more.


Just waiting on the plug (in the mail), have the Loctite 620, and will install.


Tony - Tnova

[Jagdpanzer]

Don’t feel bad Tony, also happened to me once. Now I’m extra careful when setting the pilot bearing extractor to make sure it hasn’t grabbed the cup plug.


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