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What is your question?
it dumps oil of course. put in a new seal, saw no reason or scratches or roughness. after 500 more miles it did it again. rebulder says he has never come across this problem. Any ideas why a carefully installed camshaft seal keeps coming out ? solicited ideas so far, 2000 grit emory the cam end, and then use silicone on the outside of the seal.
2 Replies
Are you SURE it was installed deep enough into the housing? I have seen this on a Honda and that was the problem there. Yes if it was installed cortectly, then 'something' else needs to be done. The silicone will help. Use clear silicone adhesive though, there is a difference! Make sure both surfaces are clean and DRY!
This was common on some of the engines. They could build pressure behind the seal and push it out. Pull the cam gear back off and make and install a retainer to hold the seal in the cylinder head.
I have the cam gear off, cleaned and dried everything, shined up the shaft end with 2000 grit, it seemed a little pocked in one spot and maybe a little ridge, looked better when i was done, didn't do much, just enough to clean it up a bit. and was going to put clear silcone adhesive to help cement the outer edge of the seal, is that what you mean by install a retainer ? what else is a retainer ? or, do you mean like cut a round piece of metal, cut out the center to overlap the outer edges of the seal, and then ? how to attach it ? jb weld ? tiny screws ( the edges around there are pretty small )?, I did have that thought though, oil pressure ? or compression pressure pushing the oil around the shaft and against the seal ? but why this motor, i've run 200 k on several other geo 3 cylinders and never this problem.
The retainer is easy. You should be able to visualize how to make it overlap the seal and reach the bolts that hold the top of the back of the timing belt cover. The reason the seal pushes out is oil pressure from the front cam bearing builds behind it and the friction of the seal against the head just isn't strong enough to hold it in the head against that pressure. Make the retainer so that it goes all the way around the camshaft. It will sort of remind you of a thermostat gasket with the two bolt holes on the ends and the camshaft hole in the middle. If you want to there is a way to drill out the oil drain passage between the front cam bearing and the seal and make a larger relief passage. BTW when the cam cap was put on, was it sealed with anaerobic sealer like it should have been or was RTV used? RTV can block the oil drain passage ,leading to even higher oil pressure against the seal.
Your reference to an oil drain passage intrigued me, so i removed the cam shaft from a practice head and lo and behold there is the drain hole, not plugged on the practice cam. Now I am debating whether to take up the camshaft to check the drain, I just checked and do not have a 10 mm deepwell I'd need to torque it back down under those tall bolts on both ends, will maybe purchase in town tomorrow before i proceed. Do you think it would be stupid not to check, given my problem with the cam seal? Seems a rhetorical question, but I don't see how gasket material, rtv or not, could migrate over from those little spots on the flange of the journal to under the center of the cam bearing surface ? Now Jan 20, putting it back together. I did take up the cam, the drain hole was clean and open. Darn. So nothing really explains it. Maybe the pcv, it did seem restricted. I have replaced with the best i could find. and will check it regularly. My fabrication came out o.k., so far, I am happy with it, I cut little tabs around the perimiter and bent them in, so it should hold the seal snugly. I measured the bore and it did not seem worn, actually measured a little tighter than given ( 1.85 ) and it was measuring 1.845. The shaft also measured pretty close, less than a thousandth off ( smaller ). So, my toes are cold now, but will soon be finishing it up and hoping for the best. Thanks again.
We would cut a piece of metal and shape it to fit and bolt it in just like you figured. If the silicone works, you're good to go. If not the retainer always did the trick.
Thanks to everyone, the retainer came out all right, and 700 miles later not a drop of oil. I would have liked to have solved why this engine, not any of the others had this problem; maybe better oil or compression pressure, dunno, pvc related maybe, but the retainer is holding, now can turn efforts to mpg's, as is getting only about 42 and am shooting for the 51 I got with my original '92, the only new car i ever bought in my life, now incorporated into my 94 and 95. Thanks again.. Ed.
O.K., I cleaned and dried everything, cleaned up the shaft a bit with 2000 grit, used clear silicone, most expensive i could find, said adheres to metal and plastic, and set the seal in just a tad deeper, where i think it is seating against a ridge. If this doesn't do it, I have figured a way to fabricate a retainer like Gillepie's below suggests, I can bolt something to a metal shield that is bolted to the motor and surrounds this area ( just below it ), so it sticks up enough to trap the seal, but don't intend to go to that extreme unless the silicone doesn't hold it. which will mean tearing it all down again. oivay !
I think you have just fixed your problem! Let the silicone set for 24 hrs before starting the engine.
It blew right out after starting it, letting it idle. Engine rebuild shop says nothing will bond metal to rubber, so silicone or even thread lock, no go. I had installed a new pvc valve, after it blew out the 1st time, but another mechanic said to get an oem original from gm, oops, no longer available, got the best one i could find. but, secondary outlet/hose feeds the base of the air cleaner housing, so don't see how the pressure builds even if pcv is clogged. I think the bore that holds the cam seal is worn, the only thing that holds it in there is the compression against the sides. They sell a sleave for the cam shaft end, but not for the seal bore. So, only thing left to try besides a new head, and this is a rebuilt new head, is to fabricate a retainer, a little tricky, but will give it a go. A gearhead friend suggested i take a punch and just ping over the metal top bottom and sides, to trap the seal in, which sounded good, but with the engine in, there is no room to get a good swing on a hammer, and, that metal is not very thick around there, think I will stick with making something. Thanks to everyone for the help and suggestions, I really want to get this car back on the road, I have a 95 and this is a 94, love the mpg's.