Need help diagnosing a possible RMS leak on the 90 GT
#1
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I finally got around to this damn oil leak issue. The car is freshly rebuilt, has only 375 miles on it. Everything was replaced but it appears that the RMS is either faulty or was not installed correctly (not sure how) or there is some other source of the oil leak at the rear of the engine.
I have the car up on jackstands and decided to pull the lower clutch cover to get an idea of where exactly the leaks were coming from.
Symptoms:
When i first started the car on the jack stands i got to a spot where i could observe where the leak was coming from. From stone cold the car ran for about 3-4 minutes without any visible leaks. I turned off the car, got under and while looking up at the backside of the flywheel i saw a drip of oil come from directly under the RMS and onto the base of the lower crank girdle. That seemed to be the only oil so far.
I decided to try again and started the car up again and was on the sides to observe any leaks. I didnt see anything for a few minutes but then noticed oil pooling on the end of the rear middle oil pan stud. Which is directly under the RMS. However there were no real significant drops. The car ran for a total of about 3 minutes this second go round and i went to turn it off.
Immediately after killing it i went to see what was going on and the leak really started. It was dripping about 2 drips per second and this lasted for probably 30-45 seconds before it stopped. So I know i have a pretty serious leak on the back side of the engine, but i still have some doubts that its the RMS because its brand new. I have done an RMS job on the other engine that I had and had no such problems with it. But I cant think of anything else behind the flywheel that could possibly be leaking.
Also I noticed at the passenger side of case oil is pooling there and about to drip, but i cant figure out what the source of this oil could be. There is nothing holding oil in the area, and i a not sure where the hell it is coming from.
Any ideas?
I know the next step is to pull the clutch and flywheel and see what i find. But I wanted to get this on the board ASAP so that i can order other parts that i may need to have for this.
I have the car up on jackstands and decided to pull the lower clutch cover to get an idea of where exactly the leaks were coming from.
Symptoms:
When i first started the car on the jack stands i got to a spot where i could observe where the leak was coming from. From stone cold the car ran for about 3-4 minutes without any visible leaks. I turned off the car, got under and while looking up at the backside of the flywheel i saw a drip of oil come from directly under the RMS and onto the base of the lower crank girdle. That seemed to be the only oil so far.
I decided to try again and started the car up again and was on the sides to observe any leaks. I didnt see anything for a few minutes but then noticed oil pooling on the end of the rear middle oil pan stud. Which is directly under the RMS. However there were no real significant drops. The car ran for a total of about 3 minutes this second go round and i went to turn it off.
Immediately after killing it i went to see what was going on and the leak really started. It was dripping about 2 drips per second and this lasted for probably 30-45 seconds before it stopped. So I know i have a pretty serious leak on the back side of the engine, but i still have some doubts that its the RMS because its brand new. I have done an RMS job on the other engine that I had and had no such problems with it. But I cant think of anything else behind the flywheel that could possibly be leaking.
Also I noticed at the passenger side of case oil is pooling there and about to drip, but i cant figure out what the source of this oil could be. There is nothing holding oil in the area, and i a not sure where the hell it is coming from.
Any ideas?
I know the next step is to pull the clutch and flywheel and see what i find. But I wanted to get this on the board ASAP so that i can order other parts that i may need to have for this.
#2
Nordschleife Master
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I had a few weeks ago suspected it was the pan gasket but when i was under the car after the first start up, i saw the oil flow from above the oil pan gasket so i have ruled that out.
Curiously the lower side of the oil pan mainly right above the starter has some oil residue on it. the entire rear half of the oil pan has a goldish tint to it, no doubt from oil residue. How did this get there?
I was driving the car over very short distances with this issue and i can understand the oil on the underside of the car aft of the flywheel, (which there is on parts of the exhaust aft of the clutch.) But how can oil get onto the lower pan. The pan does slope towards the front so i suppose gravity and not inertia could lead the oil to migrate forward, but i am not sure.
I welcome all opinions, ideas, questions....
Curiously the lower side of the oil pan mainly right above the starter has some oil residue on it. the entire rear half of the oil pan has a goldish tint to it, no doubt from oil residue. How did this get there?
I was driving the car over very short distances with this issue and i can understand the oil on the underside of the car aft of the flywheel, (which there is on parts of the exhaust aft of the clutch.) But how can oil get onto the lower pan. The pan does slope towards the front so i suppose gravity and not inertia could lead the oil to migrate forward, but i am not sure.
I welcome all opinions, ideas, questions....
#3
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Hi Ryan,
Did you put the OPG on clean - no sealant?
It is also very easy to nick the main seal during assembly - it happened to me on the FMS even though I was very careful.
Roger
Did you put the OPG on clean - no sealant?
It is also very easy to nick the main seal during assembly - it happened to me on the FMS even though I was very careful.
Roger
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
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#4
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The gasket went on dry and without sealant. This is also the second time ive installed one of these, the first one didnt leak at all.
I dont think I nicked the seal, but its possible. Its next to impossible to see the seal behind the flywheel from below, but you can see a part of it opposite the starter. I was hoping i would see the seal all torn up or something but it appears to be in good shape. I did get a small nick on the end of the crank when i pulled the old seal. its about the size of the point of a tooth pick is the best way i can describe it. I am thinking thats the cause of the leak but I am not certian. I am trying to come up with an idea of why the oil leak dosent happen when cold and why it drips almost suddenly when the car was shut down the second time. Any ideas on what could cause this ?
I dont think I nicked the seal, but its possible. Its next to impossible to see the seal behind the flywheel from below, but you can see a part of it opposite the starter. I was hoping i would see the seal all torn up or something but it appears to be in good shape. I did get a small nick on the end of the crank when i pulled the old seal. its about the size of the point of a tooth pick is the best way i can describe it. I am thinking thats the cause of the leak but I am not certian. I am trying to come up with an idea of why the oil leak dosent happen when cold and why it drips almost suddenly when the car was shut down the second time. Any ideas on what could cause this ?
#5
Captain Obvious
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Can you check the valley to see if there is any oil in there? I think Andrew had a leaking oil filler neck that filled the valley with oil and it eventually sloshed over the back of the block, then leaked down over the clutch.
#6
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Thats a very good idea and i had checked that out before and thought for sure that was the cause, but it was dry, so no, not leaking in the valley, BOY I WISH IT WERE THAT!
The car should be cool enough now to pull off the cat and get at the clutch out. So I guess I will see what we can find.
The car should be cool enough now to pull off the cat and get at the clutch out. So I guess I will see what we can find.
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#8
Captain Obvious
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check the back corners of the valve cover and the back cam plugs too. Just put your hand there and see it it's oily. Sometimes it's hard to see clean engine oils so have a good look.
I had a leak back there and it dripped oil right on to the collector of the exhaust manifold. It was embarasing to sit at the lights and see smoke run out from the gap between the hood and the fender.
I had a leak back there and it dripped oil right on to the collector of the exhaust manifold. It was embarasing to sit at the lights and see smoke run out from the gap between the hood and the fender.
#9
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I would first get out the brake cleaner and clean everything off which will help find the source of the offending oil trail.
The oil might be leaking from where the block and cradle join.
The oil might be leaking from where the block and cradle join.
#10
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yeah i was thinking that, and that would be a worse case scenario. I did not pull the crank or seperate the halves.
I would assume if this is the case that the only way to remedy the leak would be to pull the engine again and tear it down?
Has the case halves been a leaking spot before?
I would assume if this is the case that the only way to remedy the leak would be to pull the engine again and tear it down?
Has the case halves been a leaking spot before?
#11
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I thought I had a RMS leak, but I think it was oil in the valley. I replaced it anyway. I still have a leak from somewhere in front. Haven't diagnosed it yet, maybe FMS, oil pump? I need to do the TB this winter and will probably go through all of it to make sure. (BTW, I too have the realgasket - put on dry.)
#12
Captain Obvious
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yeah i was thinking that, and that would be a worse case scenario. I did not pull the crank or seperate the halves.
I would assume if this is the case that the only way to remedy the leak would be to pull the engine again and tear it down?
Has the case halves been a leaking spot before?
I would assume if this is the case that the only way to remedy the leak would be to pull the engine again and tear it down?
Has the case halves been a leaking spot before?
#13
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During diagnosis of my leak, I sprayed brake cleaner up and around the entire area behind the flywheel to get it as clean as possible. After the cleaner evaporated, I then started the engine and watched very closely (..and carefully!), and noticed darkening on top of the 'ledge' where the block and the cradle meet, directly next to the RMS on the passenger side of it. That darkening traveled along the ledge towards the passenger side of the block, where it finally hit the right-most side and migrated down to the clutch access plate, and the oil spread itself out in the gap between the cradle and the clutch-plate, but mostly collecting around that end bolt, and then drip onto the collector.
The bottom line, I was not able to tell whether it was the RMS leaking, or the seam between the block and cradle.
Has the case halves been a leaking spot before?
What happened to my car is this. I bought the car with a slight leak, and the previous owner told me about it, so there's no problem there whatsoever. I decided to change the RMS because the oil would drip out exactly like on your picture and then hit the header collector and really stink up the car.
When I did the RMS, first I changed the rod bearings. For easy access to the crank, rods, etc, I supported the engine from the rear by propping it on the clutch cover. Propping the engine that way would be no different than using an engine stand.
Once finished with the rod bearings, I then greased the lip and carefully replaced the RMS after pulling the clutch, etc, and reinstalling.
Cranking up the engine, lo and behold, the leak was much worse than before; WTF!
So either I messed up the RMS on install, or, the cradle was leaking originally, and I made it worse when propping the engine on the clutch cover.
Since that engine is out and waiting to be installed in the streeter, I will remove the cradle and reseal with 547, and install another new RMS. Hopefully when I do that I can see evidence that that was the problem.
#14
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well Lets hope its the RMS, I will have to get the flywheel off to see.
I did everything but the main bearings on the engine, so the case was not split. I had no knowledge of the case halves leaking previously. I never thought that was an issue with these engines. Even being 17 years old now. If I had read about case halves leaking I would have pulled it and resealed.
I guess its that secondary leak thats the worry, the one on the migrates to the passenger side and pools at one of the clutch cover bolt holes.
I did everything but the main bearings on the engine, so the case was not split. I had no knowledge of the case halves leaking previously. I never thought that was an issue with these engines. Even being 17 years old now. If I had read about case halves leaking I would have pulled it and resealed.
I guess its that secondary leak thats the worry, the one on the migrates to the passenger side and pools at one of the clutch cover bolt holes.
#15
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A new oil seal MUST be lubed before assembly or the rotation will immediately destroy the seal.
A small nick in the crank surface will immediately destroy a seal.
I have had more than one oil pan gasket with both types leak out the bolt holes. Remove the bolt, clean with brake cleaner and reinstall with a bunch of RTV and no more leak.
I installed one of the new gaskets with RTV and no leaks.
I installed several of the new gaskets dry and had leaks.
Why is it advised that the new gaskets should be installed dry?
A small nick in the crank surface will immediately destroy a seal.
I have had more than one oil pan gasket with both types leak out the bolt holes. Remove the bolt, clean with brake cleaner and reinstall with a bunch of RTV and no more leak.
I installed one of the new gaskets with RTV and no leaks.
I installed several of the new gaskets dry and had leaks.
Why is it advised that the new gaskets should be installed dry?