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This is one reason why I'm not too hip on oiling the gasket. It makes it easier to spit out. I know it works and makes replacment easier, but they're more likely to spit when over tightened sometimes, which as you stated, you have to do. It's even worse with covers with bolts around the edge as it will actually cut the gasket if overtightened.
Modified how? Was it welded? Sounds like it might have been tweaked in the modding process.
If the gasket is oily, it's not going to stick. (at least not very well)
Thow it away and get a new one. The cells in the cork have absorbed oil and you won't be able to get it out.
Check your cover on a flat surface and see if it's tweaked. Make sure the lip is square. If not, you still maybe able to use it.
Clean the cover lip and surrounding area GOOD. Get some 3M 8001 (I believe that is the black pt. # but I'm unsure but it is the weatherstrip adhesive, get black if you can.) 3031 comes to mind as well.
There is acouple of ways to do this:
You can put adhesive on the cover, let sit and then apply the gsaket.
Apply on both, let sit and then install the gasket.
Apply to either, set it, pull it back off and let sit for a moment and replace the gasket.
I'm not going into all the reasons for each.
When I say apply gasket, I mean to just the cover. You'll want it to dry for a good while, 24 hrs is a safe bet as you're currently having trouble with it slipping already.
It's up to you if you want to glue it to the head. I'm not going into that. If you do, it'll seal well but be a pain to get back of and clean up later for valve adjustments.
If you don't, it may not seal and sealer won't stick to it once it gets oily and you'll have to start over again.
Remember, this is an adhesive, not a sealer, so removal will be tough.
You could get another cover....but that's up to you.
Whatever you do, PLEASE. PLEASE, PLEASE, don't put ketchup on eggs !!!
Modified how? Was it welded? Sounds like it might have been tweaked in the modding process.
If the gasket is oily, it's not going to stick. (at least not very well)
Thow it away and get a new one. The cells in the cork have absorbed oil and you won't be able to get it out.
Check your cover on a flat surface and see if it's tweaked. Make sure the lip is square. If not, you still maybe able to use it.
Clean the cover lip and surrounding area GOOD. Get some 3M 8001 (I believe that is the black pt. # but I'm unsure but it is the weatherstrip adhesive, get black if you can.) 3031 comes to mind as well.
There is acouple of ways to do this:
You can put adhesive on the cover, let sit and then apply the gsaket.
Apply on both, let sit and then install the gasket.
Apply to either, set it, pull it back off and let sit for a moment and replace the gasket.
I'm not going into all the reasons for each.
When I say apply gasket, I mean to just the cover. You'll want it to dry for a good while, 24 hrs is a safe bet as you're currently having trouble with it slipping already.
It's up to you if you want to glue it to the head. I'm not going into that. If you do, it'll seal well but be a pain to get back of and clean up later for valve adjustments.
If you don't, it may not seal and sealer won't stick to it once it gets oily and you'll have to start over again.
Remember, this is an adhesive, not a sealer, so removal will be tough.
You could get another cover....but that's up to you.
Whatever you do, PLEASE. PLEASE, PLEASE, don't put ketchup on eggs !!!