Bizzare (cold) coolant leak

[Smokey73]

I've seen lots of cold water leaks on diesel engines, and the most common leak is from a gasket or clamp that is slightly loose. Id try to tighten the bolts around the pump first, If you don't see it leaking from the weep hole.

 

[Cheaper Jeeper]

Quick FYI- the pump doesnt create pressure (only flow) Pressure is from the expansion of the coolant as it heats up.
Just something i noticed reading your post.

Restricted flow= pressure. Maybe not a lot, but some.

Everyone seems on the right track for the source of the leak, but double check as it sint possible to have an accurate diagnosis over a computer- just a pointer in the (hopefully) right direction

! Says the new guy! No offense man, but I've seen folks around here nail the diagnosis on more problems than I can name. Stick around. People around here will surprise you. Lots of good knowledge in this forum...

 

[Cheaper Jeeper]

I've seen lots of cold water leaks on diesel engines, and the most common leak is from a gasket or clamp that is slightly loose. Id try to tighten the bolts around the pump first, If you don't see it leaking from the weep hole.

Good thought. Guess I better break out the mirror & flashlight before breaking out the wrenches...

 

[f-two-fiddy]

Be prepared for the fan clutch nut. Gonna need special wrenches.

That thing can be a PITA.

 

[1991idi]

No offense taken, i have learned a lot from many of these guys, they are very knowledgable with these engines. (btw low post count doesnt= new )

Good thought. Guess I better break out the mirror & flashlight before breaking out the wrenches...

Exactly what i was getting at it sounded like you were on your way to order a waterpump before checking it thoroughly

Good luck with the fix.

 

[Agnem]

Believe it or not, there is a big difference in a motorcraft pump versus the chain store brand X ones. I did a water pump for landscapeman once, and he bought a Napa Gold. I didn't know he was picking up a pump, so I got him a motorcraft. We compared the two side by side. The NAPA pump lacked machined surfaces on the pump housing, and the impeller was on a shaft that was too short. The impeller looked like it might fall off, where as on the Motorcraft unit it was a nice solid fit. The casting also appeared to have a fit issue. It did not lay flat. One would assume the bolts would twist it, so that it would seal, but I was glad he opted for the Motorcraft pump based on the other merits, and I didn't have to find out. For a part that should last 100K, I'd consider spending the extra $20 for quality.

 

[ddec4me]

I bought my pump from carquest and it works good. The only problem I ran into is that on the drivers side of the pump there is a little ear on the casting. I have a serpentine belt setup off of a 94 turbo diesel (that is the best I can figure anyhow) and that ear on the water pump and the tensioner interfear with one another it took me a couple of attempts at installation to figure this out. I just compared to my old pump and found the difference and cut the ear off (no harm no foul) Not sure what that was all about but just in case you have a problem with it bolting right up that is something to look at.

 

[Cheaper Jeeper]

No offense taken, i have learned a lot from many of these guys, they are very knowledgable with these engines. (btw low post count doesnt= new )

True if you're a lurker. But a join date of Oct '08 does = new to THIS site - and you came across as possibly passing (mild) judgement on the diagnostic ability and advice of the folks around HERE. Maybe I took your comments wrong...

Exactly what i was getting at it sounded like you were on your way to order a waterpump before checking it thoroughly

Good luck with the fix.

Nope, just getting pricing and availability. I may very well get the pump even before determining for sure that I need one - only because once I get greasy (which I will undoubtedly do investigating the problem) I want the part on hand (if needed) to proceed directly with fixing it. I can always return the part at my leisure if it isn't needed.

That's just the way I roll...

 

[Cheaper Jeeper]

Believe it or not, there is a big difference in a motorcraft pump versus the chain store brand X ones. I did a water pump for landscapeman once, and he bought a Napa Gold. I didn't know he was picking up a pump, so I got him a motorcraft. We compared the two side by side. The NAPA pump lacked machined surfaces on the pump housing, and the impeller was on a shaft that was too short. The impeller looked like it might fall off, where as on the Motorcraft unit it was a nice solid fit. The casting also appeared to have a fit issue. It did not lay flat. One would assume the bolts would twist it, so that it would seal, but I was glad he opted for the Motorcraft pump based on the other merits, and I didn't have to find out. For a part that should last 100K, I'd consider spending the extra $20 for quality.

I don't doubt you on that. However, at least in my area, the difference isn't $20. The reman is $26, but a new one (not even Motorcraft) is nearly 3x that much ($70) and Schucks lists two from Motorcraft - one for $122 and one for $229(!). If you can show me where to get a Motorcraft for $20 more than a reman I'll be all over it.

As for lasting 100k, how many water pumps last that long? I can only think of a few rigs I've owned that didn't need one replaced at some point. Plus its not like my truck is likely to last another 100k without an overhaul anyway.

 

[Agnem]

...
As for lasting 100k, how many water pumps last that long? .

The motorcraft ones.

 

[Cheaper Jeeper]

The motorcraft ones.

Yeah, well, for 230 bones they ought to last forever....

 

[Smokey73]

Big Russel('90 F250) had about 175k on the od when he got his first water pump, went with the parts store reman and I think it went about 25k. For 25 bones a pop, I don't mind changing them once a year.....IMO

 

[ddec4me]

I dont remember the name on the box of the one I installed. I know it was a plain white box with a sticker with a part # from carquest. I paid $60 for it and it was a reman. $16/core

 

[Cheaper Jeeper]

Well, for anyone interested, I pulled the water pump today (after using my dental mirror to verify that water was dripping off the snout of the pump onto the harmonic balancer).

Sure enough, there was a nice telltale rust track from the weep hole to the bottom edge of the pump casting. So I guess I found my leak.

BTW, the reman impeller looked exactly like the impeller in the one I pulled off.

To make sure I didn't mix up any of the bolts I laid the new water pump on top of a cardboard box, traced the outline, and used a phillips screwdriver to punch holes through the boxtop where each bolt hole was. Then I put the bolts into the holes in my newly-made "template" as I pulled them out.

 

[DeepRoots]

yeah, the cold will certainly start leaks.
Taking my boat from LA to NY in the winter will prove this.
Everything is tight, and than shut it down in the cold water and EVERYTHING leaks.
Just have to go tighten it up.

I just had this problem with a 4-71, when cold the shaft seal on the waterpump would leak.
I ordered a new shaft seal and they sent me a new pump.... can't beat that.

drew