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Can't find leak

1.1K views 12 replies 9 participants last post by  rangerdoc  
#1 ·
Somewhere from the back of my engine there is a small oil leak. I've looked all over and can't find it. I though it might be the back of my intake manifold, but that's not it. The small oil drips form on the front of the transmission housing. Anything else on the back end that could be causing a leak? The top of the engine is dry.

I also have some coolant coming out of what looks like a drain line for the heater box. The line looks to be about the same size as the normal coolant lines in the engine. It just hangs about 4-5 inches at the very back and bottom of the engine bay, almost to the transmission. Normal? Heater issues?
 
#2 ·
Oil leaking from your rear main seal? I noticed oil on my tranny in front so my assumption would be that.
 
#3 ·
Baby powder. Dry everything off, and put baby powder around it, and up from it.... you'll see exactly where it's coming from.
 
#4 ·
Hate to mention it, but, check for a possible crack in the block. Most common place is right above a core plug. My hope is it's a seal or gasket... and +1 on the baby powder idea.
 
#5 ·
Check the back side of your valve covers, under the lip, run your fingers around them, see if you've got any oil coming from there.

Also your oil filter, check that.

Both of those types of leaks can run down the oil pan heading aft.

Just a couple thoughts, good luck.


Eric
 
#7 ·
Back of the valve covers is a common leak area.

Good luck
Paul
 
#8 ·
I'll clean everything up and try the baby powder.

For the coolant, will it leak even if I don't use the heater? It still flows through there regardless, correct?
 
#9 ·
Unfortunately if your heater core is leaking then it will leak whether you use the heater, AC, etc, or not. You could mechanically bypass the heater core to stop the leaking until you can replace it.

Paul
 
#10 ·
The oil leak sounds like a rear main seal leak to me as well...I have the same thing going on with my car...maybe someday the car wont leak anything...:shrug:
 
#11 ·
If I'm going to pull things apart to do the heater core is there anything else I should consider replacing while I'm in there?
 
#12 ·
Heater seal kit,
Heater fan motor, switch and wiring.
Engine flush,
Thermostat and housing
Radiator hoses
Radiator flush
Radiator cap.

Most of those items are "check, clean, test".
New thermostat would be smart.
How old is your water pump?.....

When you have your block emptied of coolant it is good to inspect everything you can, but do as much or as little as you like.
 
#13 ·
I've decided I'm going to bypass the heater core for now. I'm getting ready to move and would like to get the car on the road before then. I figure this is a good project for the upcoming winter. Knowing how I am, once I have the dash apart I'm sure I'll decide to do a few "while I'm here" projects.

I'll post up if I find the source of the leak.