Need some insight on incessant Expansion Tank leak....

[MO525]

Hello again, folks.

I replaced the o-rings, top and bottom and, from what I can tell, it's the top o-ring that is leaking, running down into the lower o-ring and oozing out onto the lower hose and then onto the core support.
It doesn't leak BAD at all, just a couple 1/2"-3/4" spots on the garage floor after the wife returns from shopping or running about.
More of a nuisance than a "problem" but ANY leak is a bad leak in my book.

Any tips to get that BLASTED o-ring to NOT leak?
Believe me, I work with surgical cleanliness when I repair the car.

The car runs SUPERB, does not run hot and has no other coolant related issues that I can find, just these persistent little spots on my floor!

Thanks for the input, folks.
Bill

[MO525]

I can't seem to track it down.

Some other folks had posted their experiences with the repair.

Thanks again.

[MO525]

Hello again, folks.

I replaced the o-rings, top and bottom and, from what I can tell, it's the top o-ring that is leaking, running down into the lower o-ring and oozing out onto the lower hose and then onto the core support.
It doesn't leak BAD at all, just a couple 1/2"-3/4" spots on the garage floor after the wife returns from shopping or running about.
More of a nuisance than a "problem" but ANY leak is a bad leak in my book.

Any tips to get that BLASTED o-ring to NOT leak?
Believe me, I work with surgical cleanliness when I repair the car.

The car runs SUPERB, does not run hot and has no other coolant related issues that I can find, just these persistent little spots on my floor!

Thanks for the input, folks.
Bill

[Anton CH.]

I had the same problem, one of the o-rings had an extremly slow leak (I think it was the lower one) even after o-ring replacement. I just gave up on it and bought another radiator. I believe the m50 has a very poorly disigned expansion tank. With age, things do not align as well as they should. I thought about trying and experimenting with larger o-ring/sealent but the thought of removing the radiator outweighed any savings for me.

[MO525]

I had the same problem, one of the o-rings had an extremly slow leak (I think it was the lower one) even after o-ring replacement. I just gave up on it and bought another radiator. I believe the m50 has a very poorly disigned expansion tank. With age, things do not align as well as they should. I thought about trying and experimenting with larger o-ring/sealent but the thought of removing the radiator outweighed any savings for me.

I can see into the top of the expansion tank and see a slight weeping of fluid from the top o-ring.
Which, in turn, runs down the black plastic portion, into the larger o-ring's well, fills it then dribbles down onto the lower rad. hose onto the core support.
I've replaced both o-rings already. I'm wondering if the upper o-ring's hole is messed up somehow? I didn't SEE any scratches/damage but it doesn't take but a teeny scratch to produce a leak.

A new radiator just isn't in the funds right now.
I spent up a blue streak on the car in the past month. Ouch.

Thanks,
Bill