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Topic: coolant leak in cold temps (Read 313 times) previous topic - next topic

coolant leak in cold temps

So this has happened a couple of times over the last few years.  When the weather gets cold I start to develop some really minor coolant leaks.  The first couple of times it was usually a coolant hose at a fitting.  Just a few ounces of coolant and usually fixes itself... (right.)  The last couple of times it seems to be coming from somewhere way up near the water pump.  Of course anyone who has the ISM knows how difficult it is to see up in there to determine the exact spot.  It could be the small weep hole in the water pump?  It's dried up now I just see the residue on the garage floor.  I think it's probably nothing to worry about but I was wondering if anyone has experienced similar?
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI

Re: coolant leak in cold temps

Reply #1 –
On most of the versions of the M-11 you could have a o ring seeping at either the water pump piping slip joint or the oil cooler o rings slip joint. The water pump seal would be down the list in 3rd place at the location you describe.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: coolant leak in cold temps

Reply #2 –
I experience this phenomenon every Winter.

When it gets cold, there is shrinkage.    :(

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: coolant leak in cold temps

Reply #3 –
Quote from: Pamela & Mike –
On most of the versions of the M-11 you could have a o ring seeping at either the water pump piping slip joint or the oil cooler o rings slip joint. The water pump seal would be down the list in 3rd place at the location you describe.

Mike
That, for me.  Our 1998 U320 leaked between the water pump and the block when it got cold.  I was able to replace the o-ring without removing the pump - it swivels!  Tight, but do-able.

If this is your situation, AND you can't easily source the o-ring. send me a PM.  I think I have a couple.  I assume the part would be the same for your ISM.
Matt B
1998 u-320

Re: coolant leak in cold temps

Reply #4 –
Matt,

IIRC that is the same o ring all the way up through the M-14

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: coolant leak in cold temps

Reply #5 –
To answer a P/M question: The 8.3 block is a hog in a different wallow this info is for the basic M-11 block. So if you have a 8.3 no need to worry about caring any of these in your parts bin.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: coolant leak in cold temps

Reply #6 –
Not easy to make it out in the photo but this shot is looking up into the water pump area.  The weep hole is visible and it looks like the coolant was coming from there but it's dry now.  Also worth noting that this did not leak right away after I parked it about a month ago.  This leak started when the garage got cold.  I've since turned the heat on and I keep it at 55 degrees.  I'm not going to worry about this unless it continues or gets worse.
George Mann
2002 U320 #5934
2017 Rubicon
2013 BMW GS
Waterford MI
 

Re: coolant leak in cold temps

Reply #7 –
Have you tried to tighten the upper hose clamp?
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon