coolant leak

[Bill Root]

One of the engines in my 43' DCMY has developed a small coolant leak. I'm doing the Great Loop, so I'm running almost every day. In the last 100 hours I would say the engine has lost about a half cup of coolant.

The coolant is leaking onto the fluid absorption pads under the engine. It appears to be coming from behind the right front main mounting arms where it attaches to the block. There is no eveidence of leaking above that mounting arm. There has been no effect on the operation of the engine.

Is this a big problem, or is it something I can fix? Can it wait until I finish the trip? Any advice would, as always, be appreciated

 

[Will]

What kind of engines and is it port or starboard main. If 6-71s, you may be leaking from a hose fitting, the fresh water pump (packing or drain cock) or perhaps around the oil cooler. Sometimes you can't see small water leaks but can feel or see dampness on your fingers if you feel around those areas.
Will

 

[Bill Root]

Thanks for answering my messgae. The engine is a CAT 3126. The leak is not water, it's pink coolant. It's coming from the right side of the engine, apparently from behind where the engine mounting arm attaches to the block.

 

[REBrueckner]

Since your post did not complain about crawling around down there, perhaps getting burned or at least drenched in sweat and twisting and turning and using a mirror to see all around I'm assuming you have not taken enough time to search. Got a bright inspection light?? It can often take a number of inspections to find a minor nearly clear leak...if your engines are clean, you might try wiping a paper towel across various portions above where you see the drip evidence...sometimes the coolant is virtually invisible on the engine surface but shows up much better on a cloth or paper towel.
If the engine is dirty around there, clean off a number surfaces with a degreaser, wait a few days of runtime, then try looking/wiping.

Another approach is to inspect down there a few minutes after starting an ambient temp engine...sometimes as coolant pressure builds to to engine heating the leak is a bit more pronounced...don't know why because the physics makes little sense, but it happens.

As noted, snug all hose clamps in that area ...you don't necessarily have to actually tightenany just get a feel for the torque on several and if one seems loose, snug it up a bit...not so much as to cut the hose!!

 

[Bill Root]

Well, although I didn't mention it in the first post, I did crawl around down there, hot and cramped though it may be. The leak is not a raw water leak. It's a coolant leak, the pink stuff, so it's pretty easy to see where it ISN'T coming from.

I went back down in the engine room today and took off the belt guards. I can see evidence of some leaking through the weep hole in the bottom of the coolant pump. Apparently the pump bearings must be going.

 

[REBrueckner]

Ah, I always forget about those guards...those are the first things I took off my genny when I bought my boat....found a misaligned raw water pump and worn belt hiding under.