Pop! Now coolant leak from back of M44

[John_in_VA]

I helped a friend find this 09/98 5-spd car last fall, and told him to save up to replace the entire cooling system as the owner did not have any receipts for this. We were preparing the order last week (thanks to the great article in the Knowledge Base). He called on Saturday to say he heard a "pop" and then coolant was everywhere. He is not very mechanical.

I told him to leave the car in the retail parking lot vs. driving it anywhere. I went to see it with a gallon of distilled water, expecting to see the upper radiator hose flange broken off, but it was OK. As I added water to the expansion tank a large leak was apparent from the rear of the engine (not visually confirmed).

My working diagnosis is the plastic connector 11-53-1-743-679, but this will have to be confirmed by getting it up in the air. Sound reasonable? I hate when preventative maintenance becomes an emergency!

Thanks in advance.

[zoner]

That part is almost certainly the culprit (I hear it's not a fun one to replace...).

[Monolith]

You should be able to see it with a mirror.

It's installed mainly by feel. Two bolts. Just make sure the oring is seated all the way.

[familytruckster]

Supposedly can do it with the battery and tray removed rather easily.

[cooljess76]

Don't forget to bleed it after you replace the fitting. Very important:
http://www.318ti.org/forum/showthread.php?t=27983

[jca]

It's not an easy install, and you're right, it's done by feel. Put some lube on the o-ring before installing.

[John_in_VA]

Thanks for all the suggestion - I LOVE working by feel! Trying to get my 2002tii ready for The Vintage gathering in NC and help Bruce out with this. Will know more when we get a visual on the part.

[Noneone2]

Smart to shut it down and leave it. About $11 worth to parts, some creative language and patience will save a potential big $$ repair. I just did mine as part of the cooling system overhaul as was suggested to me as a new ti owner by a very helpful BMW tech. A 10mm wrench is needed, once loose you should be able to carefully pull it up far enough to get the hose clamps off. It does require some patience.

[spidertri]

To get to that piece I found it easiest to take out the battery, battery box, coil pack, and plug wires. You may also want to unbolt the wiring harness/microfilter shield for more room.

I took my arm and stuck it in the hole between the rear of the engine and the where the battery would be and was able to bend my elbow and get at the two screws on that piece fairly easily. It doesn't feel great, but that was the best way I found to work on that area.

[SNOWti]

Could also possibly be a broken or cracked coolant valve nozzle thing thats directly coming out of the firewall driver side. Two small hoses that send coolant into the heater core, one hose and white nozzle that sticks out from the firewall that sends coolant in and then another next to it that sends it out back to the engine. I had a leak where that white nozzle where a hose attaches had cracked and tip was broken. The tip was un-repairable so I just tossed the broken piece and re-inserted the hose a little more and re-tightened the hose clamp to it very well and no leaks, so far so good. This was the side where the coolant was going IN to the heater core circulation system, in my case.

Just a non-technical/mechanic's share of experience, may be your problem, worth knowing about and a closer look.

[roadrash]

Originally Posted by jca

it's done by feel. Put some lube on the o-ring before installing.

That's what SHE said!

D'OH! Sorry... just couldn't resist. LOL