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Earthscrew Member
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Like others, I have been hunting down oil leaks, which has become a hobby at this point. I changed the new tower cover gaskets that I just had installed when the engine was rebuilt not even a year ago with new gaskets which appears to have worked, for the moment. Then found that the cam seals were leaking, changed those, which lasted about 30 days. Then I realized that the Allen screw in the end of the cam was also leaking, removed the cam gear and reset the Allen screw with some 515 sealant. Jacked the car up, started the car and laid under there for 30 minutes with a flashlight looking for leaks, not a one. Happy day! Celebrated my victory over oil with a great gin martini, then went to bed. But, the next morning there was a small puddle on the floor, what the heck! Crawled under again with the engine running for about 20 minutes, nothing, not a new drop. Then so had my wife turn off the engine, instantly a small stream of oil poured out the bottom of the cam seal, ran down the lower radiator hose and onto my forehead, Would anyone out in Jensenville know why it only leaks when I turn it off??! Driving me nuts |
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subwoofer Member
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It doesn't leak, it marks territory.., |
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Earthscrew Member
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I actually decided to simply give in to the idea that the car will allways leak, that it is designed to leak and that everyone expects it to leak, so it best leak. However, I wrapped one of my sweat bands around the radiator hose to intercept the oil stream so nothing pisses on the garage floor. Guess I will simply change it once a month and worry about something else! |
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Brett Gibson JH5 20497 Member
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Is it the seal or is it coming out the pulley bolt, if it's the bolt, undo it and put some RTV on the threads, then re-tighten to 55 Ftlb. |
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Earthscrew Member
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Brett, I have tried the sealant on both the Allen screw in the end of the cam as well as on the bolt which secured the cam gear on two occasions in the last two weeks. As indicated, the car does not appear to leak when it is running, but the second you shut it down, a stream of oil dumps out from around the new cam seal I just installed. Only leaks from the exhaust cam due to the engine sitting at 45 degrees, I assume. Frustrating beyond belief. I do thank you for your assistance! |
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Frank Schwartz Member
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Are you sure the cam cover gasket is not the culprit?? They are infamous for leaking oil. Try putting a piece of cardboard up under the exhaust cam cover and see if it is leaking there... |
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Earthscrew Member
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Thank you for the input, but I have replaced the cam cover gasket twice as well. I first used the silicon type, no luck with that one, then tried the black rubber type which has stopped the l;eak from the bottom of the cover. I actually went so far as buying a video scope from Harbor Freight so that I could see under and around. So far, it remains that the car dos not leak until the very second AI turn it off. Again, I am beginning to think that i have to live with it like it or not! |
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gmgiltd Member
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Other possible causes depending on whether you are still using the standard airbox which is plumbed into the exhaust cam box and creates a slight vacuum when the engine is running. If you are using K&N type filters where is the breather run to? Are there any restrictions or has a PO put a PCV valve in the line? Gordon |
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Earthscrew Member
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I am running the original air box, as I did not care for the "sucking" noise that most small aftermarket system make. Should I try plugging the breather hole in the cam box, or would that simply cause it to leak all the time? Thank you ! |
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gmgiltd Member
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It's a long shot but make sure the breather hose from the cambox is not restricted or kinked. |
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Earthscrew Member
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No kinks or restrictions I can see. Does the breather serve any purpose other then directing crankcase fumes back into the engine? I would like to try plugging it because I have exhausted all other options. Regards |
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gmgiltd Member
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Plugging it would be a retrograde step as the breathers in the cambox and crankcase both prevent pressure building up internally. You may just have a damaged or defective cam seal, although why it would only leak with the engine off is a mystery - I would suggest that is the main suspect. Gordon |
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Earthscrew Member
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I wish you were right, but have replaced the cam seals last year when engine was rebuilt, and again 4 weeks ago when I replaced the cam gears. I am lost as to what to try next |
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Tim Murphy Member 
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There was a special tool designed for the cam seal install. I was told that it was very important to apply even pressure to the cam seal when installing. As I remember, the mechanic used a very large socket which rested on the metal part of the seal and tapped it in very gently. Hope this helps. |
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Earthscrew Member
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I used a perfectly matched socket in both attempts, I am beginning to wonder about the fit of the seals I have bought |
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Earthscrew Member
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Finally resolved the cam seal leak. I took the car to my Jensen mechanic in Moorpark. Kevin pulled the cam gears and seals and found very small scratches and what appeared to be a groove on both cams if you looked real close. He made sure the front oil galley drain was clear, installed a set of Speedi-Sleeves on the cams, new seals and that was the end of the leaks. It really does pay to simply take it to an expert right up front. Hope this helps someone else solve their leaks! |
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Spaceman Member 
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I have just replaced one of mine, but i think I tapped it in too far, there is an oil drain hole or two behind the seal, and I was told, if it is blocked, you will get too much pressure behind the seal, and it will puke out oil. This almost sounds like to problem you were having. So when you put in seals, do you seat them all the way? Or just flush with the cam housing? |
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redracer Member
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Just ran across this thread now and unfortunately, not in 2016 when this first appeared. The cam seals MAY score the cam surface slightly; the trick is to move the seal just a little bit farther to create a "new" seal surface. This moving can be easily accomplished by using a wooden dowel with a hole in the center for the metric bolt and then slowly pushed in past the flush surface(as you call it) There is quite a bit of room between the oil drain hole and the backside of the seal. One other thing: if you use the cheap aftermarket cam seals that have metal and not rubber on the outside, you will need to use the equivalent of #2 Permatex to seal there(just like the cheap 4 speed rear transmission seals) |
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mtechwim Member
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Did some investigation today about leaking cam covers. I found out that leaking mainly from the exhaust cam is not very strange. Because the oil return holes are in the top of the cam housing, so a whole lot of oil stays in the cam housing after turning the engine off. Just above the exhaust down pipes, really hot, that will give every kind of seal really a hard time. Maybe make a smal drain hole in the cam housing, so after engine stop an electric valve opens and the oil can find its way back in the carter throu the large carterventilation hole? Or is that a stupid idee ? On second view I looks like that each compartment is not connected to an other so each compartment must be drained, to complicated as option. Last edited on 04-30-2020 08:13 pm by mtechwim |
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redracer Member
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The early cam housings had an oil drain hole in the back, which was "plugged up" in the later housings. They felt it necessary to leave oil up there so there would not be gauling of the cam bearing surfaces during start up, one of the most damaging cycles of an engine(Smoket Yunick was of the opinion that all cars should have a pre-pressure system to relive this "oil starvation" part during start up. So, to answer your question, it would probably NOT be a good idea to put a drain hole in the back of the housings. On another note, yes you can get a leak free engine but proper preparation of the components as well as proper sealing compounds are necessary(personally, I seriously dislike silicone seals, as they are VERY VERY ineffective) |
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mtechwim Member
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I bought the rubber ones , and I will see what happens ... I’ll make the surface super clean bevor installing the gasket and covers. The cam covers where sealed with some kind of sillicon, is was very hard to get that stuff off covers and housings. And special the exaust cuffer was leaking a lot. Thanks for your replay Last edited on 05-05-2020 06:12 pm by mtechwim |
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