Cleaning, Flushing out, the Heat Exchanger

[JasperWindvane]

My AT4 [ Mr Chugger ], is fresh water [ aka-anti freeze ] cooled using raw water/heatexchanger/blah blah..

I believe that my heat exchanger, the tube, needs a good cleaning out.

On the top of the tube there is two round caps, both screwed I think..

One has much goop about it, or is that a gasget seal.

Either way, I want to open it up, clean it out, maybe replace a hose or two.

I also will replace the zinc, or what's left of it.

If you have done this? Tell me what to do ... and more importantly, what not to do.

Photo's? Love photo's. Makes the whole process easier.

ps.. I have been looking about thinking of replacing my AT4, but I have come across two take outs, both running well. With three engines [ one in boat totally rebuilt in 2001 ] I figure I can have a spare sitting in the "pit" like they do at NASCAR.

ps ps ps .. the heat exchanger for the AT4. If I was to search for one, a used one, what size, model, etc would be appropriate?

[Chris T]

FWC flushout

Hi Jasper. I clean out my FWC once a year by removing it, and soak with Vinigar in a bucket. Cleans quite well.

[JasperWindvane]

Chris T .. you take the whole heat exchanger out? I am shaky on the make up, since this is new to me. Is the outside tube there to hold the inside tube? I looked on Ebay, and none of the heat exchangers that were/are on sale looked like mine. I looked at the Moyer heat exchanger, and althought the color is different, the look is about the same.

Could you be a little more precise with how you take the HE out and clean it. I think this would be a very good part of my spring "get Mr Chugger ready" project.

[MikeB.330]

Jasper,,

Where is your heat exchanger located and what layout is your VG (standard or dinette)? I have a dinette version and the heat exchanger is installed in the space between the starboard 1/4 birth and the engine bay. It is removable but a PIA for sure. I plan to clean mine by removing the top cover and running a stiff brush down the tubes. What ever comes loose with be flushed out when the engine is started and the through hull opened.

I'll post some pictures of my installation on the Vanguard list this weekend along with the measurements

Mike

[jhwelch]

My heat exchanger is a cylinder mounted on a bulkhead, so it's just
a matter of disconnecting 4 houses and two straps. I had it custom
made about 4 years ago when the older one failed and after I had
removed it from the boat found it was made in 1959 and thus
was 10 years older than the boat!

-jonathan

[bowser bill]

atomic rebuild

Has anyone had any experience with repairing ex. valve ports with J.B. weld or similar compounds? There is a hole into the water passage below the #3 ex port. I sure don't want to find a new block. Thaks for any ideas, Bowser Bill

[Chris T]

Chris T .. you take the whole heat exchanger out? I am shaky on the make up, since this is new to me. Is the outside tube there to hold the inside tube? I looked on Ebay, and none of the heat exchangers that were/are on sale looked like mine. I looked at the Moyer heat exchanger, and althought the color is different, the look is about the same.

Could you be a little more precise with how you take the HE out and clean it. I think this would be a very good part of my spring "get Mr Chugger ready" project.

Check out Marine pin-ups September 2006. This shows my engine. The FWC is on the carb port side of engine gray in color . Bolts off, make sure you have a diagram for the hose conections. Easy job. Chris

[Don Moyer]

Bowser Bill,

Unfortunately, failures between exhaust ports and adjacent cooling jackets are the most difficult failures on which to make a proper repair. I would
not give JB Weld any chance of success.

The machine shop with which we have been partnering for many years has demonstrated the ability to reconstruct failed exhaust ports through their hot-welding process, but it is very expensive. The repair alone averages $600 and the block then has to be extensively re-machined to compensate for the warpage which ensues as a result of the hot-welding operation. The process also requires that the rest of the block is in quite good condition with respect to corrosion damage; otherwise, other cracks open up.

If anyone has any other suggestions, please come to our rescue on this one.


Regretfully,

Don