Coolant Leak

[mfarinas]

I am loosing engine coolant, but have noticed only a very small amount of coolant/water under the engine in the engine pan. I think I am having problems with the exhaust manifold.
Has anyone out there had this issue?
Any advise is very welcome.
Thanks

 

[Stu Jackson]

I think I am having problems with the exhaust manifold.

What makes you think this?

The "Usual Suspects" are hoses, connections, HX, HX bracket, pretty much in that order.

 

[centerline]

before you get too concerned about a difficult problem to solve, check the hose clamps for tightness.... a hose can begin to seep a bit at any one of the connections at anytime, and all it needs is a half turn with a screwdriver/nutdriver to stop it...

 

[mfarinas]

Thanks for the advise.
I did suspect hoses, but do not seem to find any evidence of leakage.
I removed the heat-exchanger and will have it checked at a radiator place.
My next step will be to replace very old hoses.
I only hope it is not the exhaust manifold.

 

[centerline]

Thanks for the advise.
I did suspect hoses, but do not seem to find any evidence of leakage.
I removed the heat-exchanger and will have it checked at a radiator place.
My next step will be to replace very old hoses.
I only hope it is not the exhaust manifold.

you may be able to save a lot of time and money by borrowing, renting or purchasing radiator pressure tester... one that you can hook up to the filler neck and pressurize the system to 15-18lbs.... then take a mechanics mirror and look around the block for the green leak or spray....

it may very well be the heat exchanger or the manifold, but if its not that is a lot of work to go thru only to find out it is the engine water pump seal or an old hose with a pinhole in it.

...or go ahead and try the wrenches first, you can always troubleshoot later

 

[CraigS]

Don't ignore the connections at the hot water heater. That area does not draing under the engine.

 

[SawyerCurt]

Two years ago I had a problem on my 1988 C34 (Universal 25XP) where one of the hose connection points on the heat exchanger had been rubbing against the bracket for so long a hole formed. While the HX was tight against the bracket the leak was negligible (essentially plugged by the HX), but one hard tack/jibe was all it took to shift the HX enough to fully expose the hole and the coolant quickly dumped, the engine hit 220+ degrees, and I had to be towed back to my slip. That was also when I discovered the high temperature alarm didn't work. Luckily, I had a smoke detector sitting on the shelf under the stairs above the engine and its high temperature alarm went off and I cut the engine before we had a fire.

 

[mfarinas]

After reviewing all hoses, I think I found the culprit.
It is the small "Fresh water pump formed inlet hose". Universal part number 200819.
I found the clamps were NOT stainless and completely rusted.
I had already removed the heat exchanger, so it is at a radiator place being tested and cleaned.
I also found that the hose from the seawater pump to the heat exchanger was in dire need of replacing, so a new one is on order.
I think this will resolve the coolant loss issue.
The temperature never rose above the 185 degree mark, so I do not think the heat exchanger is to blame.
This will ease my mind since we are planning an extended cruise to the Florida Keys starting in March.
Thanks for all the advise.

 

[DaveJ]

Many posters have had issues with these HX's. When I replaced mine I also covered all the chafing points on the hoses. I used automotive heater hose, cut into 3-4" lengths and sliced length wise. This was slipped over the engine coolant hoses and secured with tyraps.

 

[centerline]

After reviewing all hoses, I think I found the culprit.
It is the small "Fresh water pump formed inlet hose". Universal part number 200819.
I found the clamps were NOT stainless and completely rusted.
I had already removed the heat exchanger, so it is at a radiator place being tested and cleaned.
I also found that the hose from the seawater pump to the heat exchanger was in dire need of replacing, so a new one is on order.
I think this will resolve the coolant loss issue.
The temperature never rose above the 185 degree mark, so I do not think the heat exchanger is to blame.
This will ease my mind since we are planning an extended cruise to the Florida Keys starting in March.
Thanks for all the advise.

thanks for the update... its nice the hear that the problem was found and what it actually was...

 

[Stu Jackson]

$$ saver hint: you can replace that Fresh water pump formed inlet hose from Universal with a Toyota 1" to 7/8" 90 degree elbow hose at any auto parts store.

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