OM602 coolant leak!? - PeachParts Mercedes-Benz Forum

indybenz · #1 04-19-2022, 06:20 AM

Hello!

So this is a bit of an odd one, but hopefully universal principles apply.

There is a leak from behind this bolt. I'm not 100% sure if it's the thermostat housing or something with the water pump housing, but there is a brown substance, most likely steamy rusty water that's shot out at higher RPMs, covering adjacent areas.

This is on a 1998 Scottish Ambulance Sprinter with the OM602 (.980 or .986) with the electronic VE fuel pump (not inline) fwiw with about 190k miles.

Any ideas?

barry12345 · #2 04-19-2022, 08:46 AM

Is the hole at the bottom front of the water pump dry or wet? Water pump seal might do this. If you have actually seen the water squirt out otherwise forget this.

I might even take the belt off and check for wear in the water pumps bearing. Really sloppy and it is time for a new water pump anyways. At that many miles the water pump if original is probably somewhere near the expected end point of lasting. If everything seems dry. You might have to pressure up the coolant system to find the leak.

indybenz · #3 04-19-2022, 11:28 AM

Sorry I did not explain further!

I do have a video of it dripping out of this area, where the bolt enters the housing. I tightened it up as much as I could using various human contortions and the wrong socket. It stopped dripping for a few seconds...then started again.

Water pump itself is dry...but strangely coloured by brown steam.

barry12345 · #4 04-19-2022, 03:59 PM

Find out if the bolt extends into a source of coolant.Should be information somewhere or talk to a dealer. If not new gasket and check the housing for cracks.

If the bolt extends into a coolant area removal of the bolt and the coolant will flow out pretty good from the hole.If the bolt hole where a lot deeper than the bolt I would also expect that.

Although since you may not have owned the vehicles since new. May or may not be the original water pump. That is always an issue with used vehicles purchased with no records.

That is a fair amount of millage on the water pump if it is the original. If I felt it had to be removed I would replace it. More modern engines are more demanding to risk anything. This is a cheapie in the real world of modern costs.

indybenz · #5 04-19-2022, 04:39 PM

Looks like alternator needs to come off, that way I can actually reach the offending area/part. Ooft.

JHZR2 · #6 04-19-2022, 06:48 PM

Can’t tell which bolt you’re talking about.

Could the HG be breached to that area exterior? 60x engines are known for eating HGs.

indybenz · #7 04-22-2022, 11:53 AM

So I got the alternator bracket off (bloody thing) and alternator (seized bolts) and discovered the thermostat housing face was gummed up and cruddy. Thinking that was it, I 'restored' the gasket (in a hurry) , cleaned everything, added a TINY bit of black RTV behind the gasket, reassembled everything...and...

Still f*cking leaks. It's the 'water pump housing' that is broken. I have been trying to source a NEW one to no avail. Used ones are available but I'd prefer a new one.

Anybody know where, anywhere in the world, to get a NEW Mercedes 6032010101????

dieselbenz1 · #8 04-22-2022, 05:05 PM

6032010101 has been replaced with 6032010301

indybenz · #9 05-23-2022, 10:06 AM

Quote:

Originally Posted by JHZR2

Can’t tell which bolt you’re talking about.

Could the HG be breached to that area exterior? 60x engines are known for eating HGs.

HG as in head gasket? I'm starting to think so.

Not new but good used water pump housing and seal, and water pump installed to test it and it leaks just as bad.

It is damn near impossible to tell where it's coming from. I use a hose in the rad and a bright light and mirror and it just dribbles out very quickly from somewhere but it is not possible to tell exactly where.

JHZR2 · #10 05-23-2022, 01:54 PM

Yes HG = head gasket

It’s tough to trace this sort of thing. I think the 60x engines are need proactive replacement.