Oil Drain bolt
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Instructor
Joined: Apr 2019
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Oil Drain bolt
I have a mild problem with my 2000 Base convertible. After a period of time driving I find that the Oil drain bolt slightly loosens. This causes a slight dripping of oil enough to mess up the bottom of the engine, I notice this most when some of the oil hits the catalytic converter. Never enough to show shortage on dip stick. I attribute this to the dissimilar metals aluminum pan and steel bolt having different rates of heat expansion and cooling rates.
My question is is it wise to use some Teflon tape on the bolt to maybe mitigate this problem?
My question is is it wise to use some Teflon tape on the bolt to maybe mitigate this problem?
Melting Slicks
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St. Jude Donor '25
The permanent fix would be to drill new threads and get a new bolt, but you could try teflon tape for the cheap/quick approach.
Melting Slicks
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From: Anthony TX
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St. Jude Donor '08
Look at the face of the oil pan where the rubber on the drain plug seats/seals against.
It has to be smooth and flat. It may have a burr or some scoring. FIRST, try a new GM Oil Pan Bolt but make sure that the seating surface on the pan is able to seal against the rubber seal on the Drain Plug. I would NOT use Teflon tape or a washer. The rubber inlayed seal on the drain Plug is actually what seals.
BC
It has to be smooth and flat. It may have a burr or some scoring. FIRST, try a new GM Oil Pan Bolt but make sure that the seating surface on the pan is able to seal against the rubber seal on the Drain Plug. I would NOT use Teflon tape or a washer. The rubber inlayed seal on the drain Plug is actually what seals.
BC
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From: Anthony TX
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St. Jude Donor '08
Looks like the bottom of that pan took a pretty good digger. Are you sure its not cracked and leaking from that damage?
Clean it well and inspect that area for a crack..
OH CRAP,, I just realized that isnt the OPs pan.
OP, Take a pic of your pan and include it.
BC
Clean it well and inspect that area for a crack..
OH CRAP,, I just realized that isnt the OPs pan.
OP, Take a pic of your pan and include it.
BC
Thread Starter
Instructor
Joined: Apr 2019
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Thanks for your response. The pan and bolt on my car look in excellent condition, a little oil sprayed around but that is all, never enough oil to show being low on dip stick. I do believe that my using a crush washer is the problem, will see on next oil change coming up very soon.
Drifting
Joined: Sep 2009
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From: Prescott, Arizona
If the oil pan drain bolt rubber ring is not smooth, soft and pliable, replace the bolt with a new one which has a new rubber ring.
I ALWAYS seal all my oil drain bolt threads with a bit of silicone sealant. No drips and even if you forget to tighten it, will not fall out on its own.
Yes, the next oil drain you have to remove the old sealant from the bolt.
I ALWAYS seal all my oil drain bolt threads with a bit of silicone sealant. No drips and even if you forget to tighten it, will not fall out on its own.
Yes, the next oil drain you have to remove the old sealant from the bolt.
Racer
Joined: Mar 2020
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From: Virginia
You do know the rubber insert in the drain bolt is replaceable, right? And you need to replace it occasionally. I do it every change, but I don't think I need to.
Racer
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Advisable to avoid Teflon tape on oil fittings/plugs. Any of that tape falls off inside could cause a blockage. Best to use an oil rated thread sealer. 👍
Race Director
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As long as you're changing the oil drain plug, why not get a magnetic drain plug? I bought one a few years ago, from Ecklers(?). Anyway, it has a pretty strong magnet on it. I mean, as long as you'll have the old one out, you're there anyway. Try to get one with a rare earth magnet. I agree about Teflon tape causing issues. When we used it years ago on our transmission test stands, there would sometimes be a small piece that comes off, and would lodge in the valve body, which would screw up the calibrations. We changed to Loctite white Teflon liquid pipe sealant, which worked great, as long as you didn't gob the fitting with enough to frost a cupcake!! Worked perfect. End of problems.....
Last edited by grinder11; Jun 12, 2023 at 05:35 PM.