oil pan bolt question
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Racer
Joined: Feb 2006
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oil pan bolt question
Reinstalling the oil pan on my c5, notice at the back of the oil pan near the flywheel there are two small bolt holes that I don't have any bolts long enough to fit. Anyone have any idea what's the purpose of these two holes?
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2020 Corvette of the Year Finalist (performance mods)
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those bolts go into the bottom of the rear cover, I would be worried about it creating a leak with the bolts not present
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Racer
Joined: Feb 2006
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Thanks guys. I was able to pick up a set of the bolts. However they won't thread into anything. I can literally push the bolt all the way in until the bolt head hits the ban. These bolts are brass looking and rather long.
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2020 Corvette of the Year Finalist (performance mods)
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the bolts are fairly long as they go all the way through the pan and into the bottom of the rear cover... there should be a hole in the gasket for them to pass through into the cover, I wonder if someone had previously done some clutch/oil pan work and used silicone gasket along the bottom of the rear cover and it worked it's way into the holes and dried up which will keep the bolts from going through
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Burning Brakes
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From: England United Kingdom
If they are going all the way in until the under side of the bolt hits the pan , are those bolts to short or maybe the threads are stripped in the cover, correct diameter i.e. m6 ?
Just a thought
Team Owner
Joined: Sep 2001
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From: Lake Elsinore, CA
There are some obvious differences in your pan versus the pic of mine that I posted above. For instance, yours is missing the rear center bolt mine has. Also, the areas with the screw holes where you're missing screws are not protruding like they do on mine. I'm not familiar with year-to-year differences in lower oil pans so I can't say if yours never had the screws or not. What year C5 is yours?
Also, if screws are missing, did a PO strip those holes out and drill them out to a larger size in an attempt to re-tap?
Also, if screws are missing, did a PO strip those holes out and drill them out to a larger size in an attempt to re-tap?
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Insert a metal ROD in the pan hole until it hits the block. Mark the rod and measure that length (that will be the hole depth).
Your bolts will need to be APPROX an inch longer or (slightly less than the actual threaded hole depth so the bolt doesn't bottom out in the threaded block hole)
You could insert a thin wire into the hole and then make sure that it goes into the threaded hole to get the total length of the hole and threaded hole in the block.
Bill
Your bolts will need to be APPROX an inch longer or (slightly less than the actual threaded hole depth so the bolt doesn't bottom out in the threaded block hole)
You could insert a thin wire into the hole and then make sure that it goes into the threaded hole to get the total length of the hole and threaded hole in the block.
Bill
