That’s great news. Hopefully the sealant and tightening it further prevent any more oil leaks and you can get it on the road!
Mystery Oil Leak After Engine Rebuild
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Did you see this thread?
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Cleaning the threads in block of all oil and the use of a good sealant seems critical.
MrMCar recommended Permatex Form-a-seal #2...non-hardening sealant.
Massive oil leak after rebuild (solved: oil gallery plug)
I treat it as a pipe plug. My hands tell me when it's enough. Sealant does the rest.
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Cleaning the threads in block of all oil and the use of a good sealant seems critical.
MrMCar recommended Permatex Form-a-seal #2...non-hardening sealant.
Yeah just read this earlier today. Will start it up tonight and see if it holds any better this time around, might try Permatex #2 if it's still no good.Did you see this thread?
Massive oil leak after rebuild (solved: oil gallery plug)
I treat it as a pipe plug. My hands tell me when it's enough. Sealant does the rest.
Cleaning the threads in block of all oil and the use of a good sealant seems critical.
MrMCar recommended Permatex Form-a-seal #2...non-hardening sealant.
My biggest concern is still whether driving it all the way in is the right way of going about it? Ideally would leave it flush with the outside surface as it was from factory but both the sealant I used as well as the #2 are non-hardening so doubt they'd hold unless threaded all the way in. What the hell is the blue stuff that BMW uses? I really doubt it's just blue Loctite.
The type of sealant used should have been quite apparent on removal. If the fastener doesn't seat against anything and isn't a taper thread, it requires an anaerobic thread locker to lock and seal against the oil pressure. Loctite 242 is rated for 100% strength in motor oil at 125°C. I had to look how the preapplied stuff works. It contains micro capsules which burst on installation to release the chemicals which do the work. Loctite has a product specifically for this application.
To have that much of a leak, it has to be pressurize oil, not just a crankcase leak. The crankcase should be below atmospheric pressure, so other than seepage shouldn't leak significantly.
As far as the crank sensor, the o-ring does the sealing. The single bolt has no influence on the seal. If you are concerned about it leaking, pull it and inspect the sealing surfaces and o-ring for damage. We trust o-rings for virtually every other far more critical connection under the hood.
To have that much of a leak, it has to be pressurize oil, not just a crankcase leak. The crankcase should be below atmospheric pressure, so other than seepage shouldn't leak significantly.
As far as the crank sensor, the o-ring does the sealing. The single bolt has no influence on the seal. If you are concerned about it leaking, pull it and inspect the sealing surfaces and o-ring for damage. We trust o-rings for virtually every other far more critical connection under the hood.
Which one is that then?
Pretty certain now that the gallery plug is the main leak, the crank sensor has remained dry since reseating in with a new O-ring and the pool under it the first time must have been oil that ran into the pocket there down from the gallery plug along the backing plate.
I've cleaned everything up and reseated the plug with a generous dose of blue Loctite 243. Will try it tonight as see how it holds.
Would be great to know what the actual stuff that BMW uses is though and seat it with that for peace of mind. Looks blue but I suspect it's something stronger than regular Loctite.
Did pop into the local BMW dealership earlier today and sure enough they're as useless as you'd expect. No idea what the sealant is, no stock on the plugs with sealant already pre-applied and at least a month's wait on getting them in. Love it.
Ladies and gentlemen, we have a winner! Regular blue Loctite 243 looks to have done the trick. Ran the car for about a minute, no drips. Took the flywheel off and everything looks bone dry. Previously, it would start to pour out within seconds. Finally! Might actually take it for a drive this weekend.
Thanks team!
Thanks team!
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Good stuff...Did you fully seat the gallery plug, or did you leave it flush(ish) to the surface?
Glad you got it sorted!
Honestly only the engineers can probably tell you what sealant is used by BMW. All those "micro encapsulated" fasteners come from BMW with the sealant/thread locker already applied and are considered one time use for that reason. When you read BMW's repair instructions that's often a reason for replacing a fastener.
Honestly only the engineers can probably tell you what sealant is used by BMW. All those "micro encapsulated" fasteners come from BMW with the sealant/thread locker already applied and are considered one time use for that reason. When you read BMW's repair instructions that's often a reason for replacing a fastener.
Oddly enough some of the loctite datasheets say the pre-applied stuff is reusable, I only looked at a few. Pre-applied is used to speed up assembly. Using liquids at home is just fine.
And you're right. I was wondering why I read flywheel bolts need to be replaced, when the fastener isn't TTY. After removing them, it was obviuos they used threadlocker to seal the through holes in the output flange on the crank.
Loctite sets regardless if the fastener is torqued or not.
My best guess without reading all of the datasheets is Dri 506. It's not something you can buy in a tube. The std blue you used will be every bit as good.
Just about, maybe a mm in from the surface, definitely not all the way in.
Video
At the same time also fitted the plug on the old engine as a test. Took it out the next morning to check and it looks to have set pretty well.
Compare that to the Permatex 59235 that got completely washed out and didn't set at all. No idea how it worked for 50sKid but good on him.
Took the scenic route but looks like there's light at the end of the tunnel. Fingers crossed.
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