Heat exchanger care/maintenance

[Darol Wester]

I've been running a heat exchanger on my 350 Chevy/Merc for about 10 years now and was wondering what type of maintenance/cleaning these things need and how often. The motor was starting to run on the warmer side, but after looking at the exhaust manifolds condition, I figured it was probably the culprit. This system gets in the salt a fair amount every year.

So what's the story on H/Exchanger maintenance?

 

[stonyloam]

Re: Heat exchanger care/maintenance

On my 470,which may be significantly different from your exchanger, they recommend every couple of years to remove the endcaps (only raw water there, the antifreeze is sealed inside the exchanger) inspect and clean the inside of the tubes. Backflush or clean with a long brush. That is about it, should have new endcap gaskets on hand. Make sure the antifreeze is about 50/50 and in good shape. Make sure the radiator cap and tube to the overflow tank are in good shape. You can do a cooling system pressure test (borrow the tools from autozone). Make sure you impeller is in good shape. If your temp is creeping up, I would suspect the impeller if it has not been done lately.

 

[Don S]

Re: Heat exchanger care/maintenance

If they are getting a build up on the tubes, they can sometimes not transfer heat as they should. A trip to you local radiator shop to get them "Boiled out" and cleaned usually makes them work like new again.

 

[Darol Wester]

Re: Heat exchanger care/maintenance

I removed the end caps and found the inside to be clean as a whistle. The tubes were excellent. I changed the antifreze solution last year and it looked fine too. No debris of any kind mixed in with it. I'm gonna replace the caps with new gaskets and take it for a run.

 

[Don S]

Re: Heat exchanger care/maintenance

Have you checked the impeller?
Just drain the manifolds and pull the risers and check. 10 years and salt water usually means the exhaust is plugging up.

 

[Darol Wester]

Re: Heat exchanger care/maintenance

That's where all this started Don. I was on the lake 2 weeks ago and noticed the temps were rising faster and higher to where it set of the temp alarm at 210. Long story short, I'm in the process of replacing both manifolds and risers and they needed it. Somewhere I was reading that that alone would cause the temp problems I was having. Lots of crap in them.

I replaced the complete impeller pump last year so it should be fine.

 

[Don S]

Re: Heat exchanger care/maintenance

Somewhere I was reading that that alone would cause the temp problems I was having. Lots of crap in them.

Of course it will. The water coming into the engine and going out is what cools the engine. Since the exhaust is the only way out for the water, if it can't get out, it gets hotter.