Magical oil leak

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Toluene56

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I have an oil leak I have been battling.
Magnum block 5.9
408 blueprint short block.

At first it was a leak from the rear main. I have replaced the rear main seal twice. This last time I even installed a new oil pan and new gaskets since the other one didn't look to healthy. I have nipped all other oil leaks. Filter is dry, valve covers dry, distributor and oil gauge fittings are dry, intake manifold is dry. Only other problem I can figure is oil plugs in back of block leaking... is there anything I may have missed?
Thanks
 
You say you've checked the pressure sender fittings, but have you checked the pressure sender itself for a leak that happens only while under running pressure?
I have an 86 Laser XT. There'd be a drop or 2 of oil under the car. I'd look for leaks, wipe & find nothing. When the leak finally got worse, I found it was spitting oil from the sender itself, but only after a spirited drive. Under pressure it leaked. New sender, problem gone.

HEY, just noticed I passed 1000 posts.
 
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Looks like you covered all. Oil plugs may be the problem.

IMG_0102.JPG
 
You say you've checked the pressure sender fittings, but have you checked the pressure sender itself for a leak that happens only while under running pressure?
I have an 86 Laser XT. There'd be a drop or 2 of oil under the car. I'd look for leaks, wipe & find nothing. When the leak finally got worse, I found it was spitting oil from the sender itself, but only after a spirited drive. Under pressure it leaked. New sender, problem gone.

HEY, just noticed I passed 1000 posts.
yeah even after a nice hard tire burning thrash.. everything is dry as a bone except for the oil coming out the bell housing.. Even the oil pan itself is relatively clean now. This last rear main seal cut the oil puddle down quite a bit. I guess after this heavy week of car shows i'll tear the engine out and upgrade a couple things while I check the oil plugs.
 
I don't see any mention of the dipstick hole , mine is a sumabitch , then of course the fan blows it back across the pan and makes it look like it's coming fro the back .
 
I don't see any mention of the dipstick hole , mine is a sumabitch , then of course the fan blows it back across the pan and makes it look like it's coming fro the back .
it is dry... as of now anyways.I figure if it were anywhre else the pan and the front K member would be soaked.
 
yeah I run full synthetic and that stuff seeps through the tiniest places , I had one valve cover that seeped when running a tiny bit but it would run down the back of the motor and under like a rear seal as well , I guess thats what keeps the hobby interesting eh !
 
Good. Do you have a computer based camera that you could mount and have a passenger observe while you are driving ? Might be a way to see what's going on.

Ken
 
Good. Do you have a computer based camera that you could mount and have a passenger observe while you are driving ? Might be a way to see what's going on.

Ken
Funny enough I just purchased a small action cam. I'm also ordering a small borescope that will connect to my tablet so I can run it up behind the flex plate and hopefully get a visual of the plugs to see if they're wet with oil. Might be a few days before I get to see the real leak. But I do plan on putting in a new cam, so if I have to pull the engine to fix oil plugs I won't be too butthurt haha.

Edit I also did a real stupid thing and lifted the car securely and then let it idle while I shimmied underneath to see if I could see an active leak.... and nothing it was dry as a bone, up until it sat back down and oil dripped from inside the trans housing.
 
Funny enough I just purchased a small action cam. I'm also ordering a small borescope that will connect to my tablet so I can run it up behind the flex plate and hopefully get a visual of the plugs to see if they're wet with oil. Might be a few days before I get to see the real leak. But I do plan on putting in a new cam, so if I have to pull the engine to fix oil plugs I won't be too butthurt haha.

Edit I also did a real stupid thing and lifted the car securely and then let it idle while I shimmied underneath to see if I could see an active leak.... and nothing it was dry as a bone, up until it sat back down and oil dripped from inside the trans housing.


Not dumb if it was secure. I do that when I need to see what's going on.
 
Have you tried the UV dye that you can put into the oil? I've used that stuff a couple of times on leaks and it really takes away the guesswork.
 
I fought a " magical" oil leak a few years back.
Brand new small block stroker motor from a high end Mopar shop.
Thought it was the rear main. Swapped it out twice on my back in the garage without a lift.
Didnt fix it.
Finally took the car and put it on a lift and yanked the tranny out.
Oil was leaking from the cam plug............
 
Sorry to hear. Fighting the same thing.
Leaks just enough to piss me off.
I can lay up under it running for half an hour, and not a drop, but park it and it drips a quarter size spot from the bottom of the bellhousing.
Hoping mine is the oil line to the guage. Finally got the valve covers sealed up good ( I think ) ,but the starter is getting wet.
Don't know where else to suspect coming from that high. Head bollt, or gasket?
Should ARP head bolts be re-torqued with aluminium heads after installation?
 
have you taken a spray bottle of whatever to the inside of the bellhousing?
it is possible there is oil puddled in there from the last leak and still dripping down
 
have you taken a spray bottle of whatever to the inside of the bellhousing?
it is possible there is oil puddled in there from the last leak and still dripping down
Yea I have cleaned it out every time to check for new leaks. I'm pretty sure it's gonna be one of the plugs in the back of the motor.:BangHead:
 
The UV dye is the best way to locate at this point, IMO.
 
This is a real bummer. Just glad to read that I am not the only one with these problems.

Still trying to determine if my leaks are the rear or front seals or the oil pan.
 
The UV dye is the best way to locate at this point, IMO.
I'll grab some dye and try it out as well.. I did buy a cheap little borescope for my tablet.. So i'll test it out and see how well it works when I get it.
 
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