leaky engine
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Joined: Aug 2013
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From: Syracuse NY
leaky engine
Getting very frustrated trying to find the source of an oil leak on my 84 CFI engine. I get a steady drip down the front face that drips on the frame and runs down the pan and then is carried back by the wind when driving. It had a new timing chain/cover, valve cover gaskeys, all new pan gaskets (Incl. Rear main seals), over the winter. Just got done replacing the intake manifold gaskets (and opened the intake ports while in there) yet I still get a leak down the front somewhere.... very frustrating. Are there any other things to look for like freeze plug or other ports, bolts that should have been sealed like the water pump.of timing cover? Tired of working in this cramped space where it is hard to see the block when all the pumps, pullets and harnesses are installed. May have to start pulling off pulleys and the harmonic balancer so I can see where the leak is...
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From: moraga ca
There is a bolt on the front of the motor on the passenger side that on older motors was used to hold the fuel pump pushrod during installation. If it is not tight, oil can leak out there. It is near the bottom of the block next to the water pump.
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Joined: Jan 2014
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From: San Francisco California
Best thing to do in a case like this is to hit your local auto parts store and get a dye. The UV light will pretty much pinpoint the source of the leak.
I can relate to your frustration, I just fixed a really bad rear intake manifold seal leak on mine. I had a heckuva time figuring out where it was coming from until it got really bad.
I can relate to your frustration, I just fixed a really bad rear intake manifold seal leak on mine. I had a heckuva time figuring out where it was coming from until it got really bad.
Instructor
Joined: Jan 2014
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From: San Francisco California
BTW, one less thing to worry about...freeze plugs are for coolant so no worries there...there are five 1/4" NPT pipe plugs (three at the back of the block above the 23/32" expansion (cam) plug, one by the oil filter pad, and one on the driver's side deck towards the rear), but none are on the front. There are three 1/2" expansion plugs on the front for the oil galleys, but they are under the timing chain cover so no worries there.
I would definitely try the dye next
I would definitely try the dye next
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From: Syracuse NY
BTW, one less thing to worry about...freeze plugs are for coolant so no worries there...there are five 1/4" NPT pipe plugs (three at the back of the block above the 23/32" expansion (cam) plug, one by the oil filter pad, and one on the driver's side deck towards the rear), but none are on the front. There are three 1/2" expansion plugs on the front for the oil galleys, but they are under the timing chain cover so no worries there.
I would definitely try the dye next
I would definitely try the dye next
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Joined: Aug 2013
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From: Syracuse NY
Will look for it. There appears to be a small stud of some kind near the top-center of the block over the water pump but not sure if that is a source. Will get dye and see where it leads me. Thanks.
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From: Syracuse NY
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Joined: Aug 2013
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From: Syracuse NY
Dye test done....
While is is very hard to see much of the front of the engine with the balancer, A/C, water pump, smog pump and all the associated hoses and wiring harnesses, the only puddle that was evident was where the oil pan met the block at the timing cover on the passenger side. There may be other areas, but as this drip appears to hit the rubber porting of the harmonic balancer and then sprays it everywhere. Even found some UV residue on the steering shaft where it enters the power steering gearbox. So I guess the next step is to check the front pan bolts for adequte torquing and then pull the balancer off the crankshaft just to be sure that seal is not leaking and the rest of the timing cover gasket. Doing anything more means a lot of disassembly ....again. At least the intake manifold does not show any leaks!
Very frustrating... Stay tuned!
Very frustrating... Stay tuned!
Instructor
Joined: Jan 2014
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From: San Francisco California
Hmmmm...sounds like it might be either loose pan bolts or perhaps a bad front seal then.
Since the dye is still in the oil, can you clean the area again and then take one more look before the engine has had enough time to splatter?
Sorry to hear it wasn't obvious yet, but as always, a process of elimination...at least we've eliminated some potential sources already...sounds like you're getting real close!
Since the dye is still in the oil, can you clean the area again and then take one more look before the engine has had enough time to splatter?
Sorry to hear it wasn't obvious yet, but as always, a process of elimination...at least we've eliminated some potential sources already...sounds like you're getting real close!
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From: Syracuse NY
Hmmmm...sounds like it might be either loose pan bolts or perhaps a bad front seal then.
Since the dye is still in the oil, can you clean the area again and then take one more look before the engine has had enough time to splatter?
Sorry to hear it wasn't obvious yet, but as always, a process of elimination...at least we've eliminated some potential sources already...sounds like you're getting real close!
Since the dye is still in the oil, can you clean the area again and then take one more look before the engine has had enough time to splatter?
Sorry to hear it wasn't obvious yet, but as always, a process of elimination...at least we've eliminated some potential sources already...sounds like you're getting real close!
However, I drove it again today and still got a decent puddle under the front of the engine.
I am getting quite a nice oil film on the underside of the car and need to get this stopped. Guess next step is to pull the balancer and see what is happening there. As the timing chain, the cover, the balancer and seal are new last fall, I would not think that would be the issue, but I may have to go there and see. May try and flip the A/C compressor back to get a better look at things before the deeper dive, including a better view of the fuel pump bolts people were mentioning. Stay tuned...
Last edited by Scott0757; Sep 15, 2014 at 12:39 PM. Reason: typo
Team Owner
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From: Park City Utah
There is likely oil all over the front of the motor from your leak, by the sound or it.
Get it CLEAN, then you can readily see the leak. I would take it to a self service car wash and hand power-wash the whole engine, but especially the front. Get the wand down in there between/behind/around the accessories and just blast it all. Get the x-member clean, all of it. Then drive it home, inspect for a leak.
Bring a jack if your ambitious and jack a side and get underneath too.
not only does cleaning help you isolate the leak easier, it makes working on it much more pleasant.
Get it CLEAN, then you can readily see the leak. I would take it to a self service car wash and hand power-wash the whole engine, but especially the front. Get the wand down in there between/behind/around the accessories and just blast it all. Get the x-member clean, all of it. Then drive it home, inspect for a leak.
Bring a jack if your ambitious and jack a side and get underneath too.
not only does cleaning help you isolate the leak easier, it makes working on it much more pleasant.
Last edited by Tom400CFI; Sep 15, 2014 at 02:09 PM.
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From: Syracuse NY
Found the leak at the lower left side of the timing cover, just above the pan gasket. Steady ooze down the pan and then around the pan seals. Started front end tear down tonight to pull and reseal timing chain cover. If memory serves me correctly, I remembered a slight offset between the front of the pan and the block that may be just enough to cause a gap. Will clean and RTV the hell out of it.
Also noted the cover over the unused fuel pump area was leaking too so will reseal that when I have everything else out of the way. Trying hard not to break the seal on the A/C unit but it really is in the way.... all the time.
This had better do it!!!
Also noted the cover over the unused fuel pump area was leaking too so will reseal that when I have everything else out of the way. Trying hard not to break the seal on the A/C unit but it really is in the way.... all the time.
This had better do it!!!
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Joined: Jul 2014
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From: Alabama
Outstanding. Are you dropping the oil pan as well? Heard its not impossible but tough to seal the TC cover without dropping the pan. Only reason I haven't fixed my leak yet. My luck isn't too good.