How to determine bad heat exchanger

[carpetman727]

I have Hydramaster CDS, one of the heat exchangers is bad due to water backing into the coolant reservoir. Is there a way to determine which heat exchanger is the bad one? Thanks in advance for any input.

 

[Lee Stockwell]

Bypass one of them.

 

[Lee Stockwell]

There is a leak or split tube in the high pressure side pushing cleaning water into the low pressure cavity.

 

[dealtimeman]

Some are repairable just depends where the crack is.

 

[Nomad74]

Is the water cold? Sorry, I couldn't help myself.

But on the serious side, get a harbor freight thermal laser pointer thing. Point it at the exchangers and find your cold spots.

https://www.harborfreight.com/hand-...d-thermometer-with-laser-targeting-69465.html

 

[Lee Stockwell]

I have one, probably wouldn't help.

 

[Doug Rice]

I have one, probably wouldn't help.

I don't think a cold spot will show up as one is probably cooler all the time as it is downstream. I agree with the bypass idea. It might take a bit of simple plumbing to do the changeover but it is a good way as the HX most likely will leak more when heated. You will have to run for a while to figure it out but be patient. I have a local dealer that sends them out to a radiator shop to check them for leaks. Where are you located at?

 

[Lee Stockwell]

On my WM, which is a typical set up, a van coolant hose goes into the first hx, then a jumper hose goes from the exit of that hx to the inlet of the second hx. The outlet hose from the 2nd hx goes back to the engine, usually via a Tee in the lower radiator hose.

Usually one of the hx hoses is long enough to do the bypass without much trouble.

A screwdriver or hose clamp nut driver is all that is needed. (sorry Marty)

Further diagnostics:

If water NOW comes out of the bypassed hx open hose barb you have the bad one. Go ahead and bypass the high pressure hoses to that hx and then remove the hx for repairs.

If high pressure water continues to overfill the van's coolant and overflow the radiator.....you guessed wrong and bypassed the GOOD hx. Go back and pull the other one.

You will still get pretty good heat with one hx, but go ahead and get the other one fixed. Respect Murphy.

 

[Jimmy L]

Maybe pull both and get fixed updated before the other one goes.

 

[Desk Jockey]

I have Hydramaster CDS, one of the heat exchangers is bad due to water backing into the coolant reservoir. Is there a way to determine which heat exchanger is the bad one? Thanks in advance for any input.

When it happen to my Butlers I had to replace the heat exchanger each time. They could have cut the box open to find the hole or holes but didn't put much stock in finding it with cutting it to ribbons.

Sorry, its a major hit, hopefully you have had it many years and made good money off it. Ours had been in the field quite some time before failure.

 

[Brian H]

Over the years, we have cut a few Butler heat exchangers open, repaired the leak and then re welded them.