Coolant leaking from behind oil pan?

[parad0x]

Hey guys, I dont know whats goign on.. but its a pretty bad coolant leak from behind the block! It only leaks when the engine is hot and not when its cold. I am having a hard time tracing the coolant leak as it's really hard to see. What could possibly be causing cooling to drop off from the oil pan behind it? LIke I get about a drop every second of coolant? I would understand if it were leaking coolant from the radiatior.. but I cant seem to trace it to the back the original source?

Are there any hoses at the back of the engine or something? (very awkward if there is).. Could hte coolant possibly be flowing down from like the thermostat housing to the back of the oil pan ? My fear is this might be a cracked block.. Could this be remotely possible ?

This is on a 1992 E36 4door 325I automatic.

[parad0x]

k, i got underneath the car again with a flashtime this time. I managed to notice there was coolant dripping from a few spots.. one was right between the seem between the engine and the automatic transmision..

The second spot was through these small two holes underneath the engine, just above the black cross bar on the underside of the front of the vehicle. There are two small holes, to which you can see the internals of something (motor or tranny?? i dont know).. Through the hole I can see coolant flowing down and out the hole (its not a cracked hole, its just two fabricated circular holes im guessing for some sort of ventilation??). When I saw the inside through one of the two holes, I saw this bolt.. to which you can see coolant dripping off of.. So now this leaves me even more puzzled? What do you guys think this might be? This couldn't be a headgasket issue or something could it? Or possibly a cracked block ?

[jagerking]

Do you have any pics man? I'd love to help you out, but I can't picture where youre telling us right now.

[Bimmersoul]

I had this exact same problem. I was told it was a block water-seal (don't know the exact name). You (or your mechanic) need to bring down the transmission in order to fix this problem.

I was charged $250 which was mainly the transmission labor since the seal was less than $3 Dlls.

I never knew if my mechanic was honest but he has always being so. I checked the heater valve hoses that are closed to the firewall and they were fine... so I believed him.

Good luck

[APKhoas]

How cold is it getting in BC now? The block seal plugs are designed to fail first in a freeze situation. They can leak for no apparent reason too, so it doesn't have to be a freeze. Just saw BC and wondered if it had been out in a early cold snap with not enough coolant to prevent a freeze.

[Bimmersoul]

Over here in TX is rather common for block seal plugs to fail even at our climate temperatures mostly over 98°. So… as stated above, they do fail with no apparent reason.

[themadhatter]

sounds like it could be the plastic port going to your heater core. I forget the name but they are known to give after awhile.

[APKhoas]

sounds like it could be the plastic port going to your heater core. I forget the name but they are known to give after awhile.

German engineers got a hard-on about plastic parts for the heater circuit. Porsche has them too. Always a weak link, and definitely worth checking.

Get yourself an inspection mirror and have a good look at the head to block junction and anything in the water circuit around the back of the head. Its frustrating, and you'll need a good strong flashlight, but you should be able to see the leak. Might need to take some covers off to get decent access.

[krayon]

BUMP!

I am having this same problem. Has anyone ever replaced a freeze plug? To the OP, did you ever solve the problem, and if so what did you do?

Can someone point me in the right direction? Thanks

[Bimmersoul]

BUMP!

I am having this same problem. Has anyone ever replaced a freeze plug? To the OP, did you ever solve the problem, and if so what did you do?

Can someone point me in the right direction? Thanks

Krayon,
In my case, as steted above, it was a block seal. Less than $5 part but they had to bring down the tranny.
My symptoms was: Noticiable leak when hot (leak not a stream). No leak at cold idle and I was able to drive the car for 25 miles in order to get home. At the following day, I filled the reservoir (had a little bit water at the bottom) and took the car to the shop (aprox 7 miles away) with no problems.

Hope that helps.

[parad0x]

Hey guys ive got an update. For starters, sorry I was not able to get back to all your comments right away as my internet / electricity was offline for a Loong time, and so much other shit hit the fan at the same time I dont want to even bring to this dicussion... I have to say this is by far the worst luck iv'e had in a long time, and my car has been parked on the side of the road for the last 1.5 months stuck under pikes of snow....

I have however taken all of your suggestions, and have had a closer inspection at the problem and have spent several hours working on the car yesterday, its like impossible to see where its coming from. I have narrowed it down though to some hoses (2 on top of another 2) to the drivers side of the engine, at the back closer towards the firewall. It's like right underneath the intake manifold! I have no clue how im gonna get at this, it looks like a nightmare, almost as if I have to remove the intake manifold to replace this one silly part which looks like a hose. I will be going to the automotive store today or sometime soon, to pickup some fluorescent light(s) of some sort so I can see better where this leak is coming from. What makes no sense, is how I cant follow the trail or make any sense of how this also causes a leak down by the bottom out of the two holes behind the oil pan? I truly hope this is not Two leaks that I have going.

If anybody know what these 4 hoses are to the drivers side of the engine let me know, or how others might have tackled them the problem.


themadhatter: Are these 4 hoses to what you were referring to ?

jagerking: I will try to take pictures of it.

bimmersoul: Where about is this block seal? where does it go inbetween?

[parad0x]

An update. Just went down to local auto store and picked up one of those automotive car light lambs, anyways.. Was real handy today, I confirmed a leak from one of the 4 hoses coming form the heater valve assmebly thing. I saw the leak dripping a drop every second or so from this hose. Unfortunately this hose is directly underneath the intake manifold, and is at the rear most portion of the engine bay, **** real pita.

Anyways, after like 4 months of the car being off the road, insured just to keep it on the road I am determined to fix the issue now lol. I have begun the task of taking off the intake manifold (after having read like 6 different diy's, all must I say very vague).

[bimmerman1982]

I think I have the same thing going on. It looks like it is leaking from the are where the trans and block seat. I thought it might be a head gasket, but there is not coolant in the oil and no somke from the exhaust. what's the best way to view the area behind the block, just drop the trans?

[parad0x]

bimmerman, I dont know if this will help you but I have found my culprit and it was one of the heater core hoses(there are a few of them).. its right underneath the manifold, at the rear. Its extremely hard to see them from any point of view, i had to take a fluorescent light and put it right underneath the intake manifold, to see the hoses at the very back of the intake manifold. It took me many hours to finally have taken it apart. If you wish, you may navigate your way to my other threads, where I am more focuses on solving the issue. I am at the step of having my intkae manifold removed completely, and the hose is on my desk that was leaking. tomorrow I will go to the dealership/auto parts store to pickup a replacement hose and some gaskets for the throttle body and the intake manifold.

[bimmerman1982]

bimmerman, I dont know if this will help you but I have found my culprit and it was one of the heater core hoses(there are a few of them).. its right underneath the manifold, at the rear. Its extremely hard to see them from any point of view, i had to take a fluorescent light and put it right underneath the intake manifold, to see the hoses at the very back of the intake manifold. It took me many hours to finally have taken it apart. If you wish, you may navigate your way to my other threads, where I am more focuses on solving the issue. I am at the step of having my intkae manifold removed completely, and the hose is on my desk that was leaking. tomorrow I will go to the dealership/auto parts store to pickup a replacement hose and some gaskets for the throttle body and the intake manifold.

Thanks, I will definately look into that.