Stop Leak Heat Exchanger?

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ERTF

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Getting saltwater in my westerbeke generator coolant. System is getting overpressurized and leaking out manifold cap and coolant pump. I tested my heat exchanger and it is leaking in a few of the tubes.

My friend also has a westerbeke and told me he was getting excess pressure in his coolant system and suspected it was the manifold.

I despise westerbeke for their price gouging. So before I spend the money on a new heat exchanger, I want to make 100% sure that is my only source of saltwater (not the manifold).

I've read both praise and warnings from people who put stop leak thru their engines cooling system. I'm wondering if that stuff can work without being hooked to the engine? Is it possible to put stop leak in my exchanger independently, then flush it out, then reinstall on engine?

Once again, my main goal is to get it to hold for enough hours to confirm or disconfirm that is my only source of saltwater.
 
stop leak is unlikely to remain in the salt water side since it constantly flushes.
You can remove the exchanger and using plugs and air pressure under water see where it is leaking. Brazing the leaks may be possible.
There is /was a company in your area that makes heat exchangers for many engines. Lots cheaper than OEM markup
 
Im going to guess that an aftermarket HX is available.
 
Im going to guess that an aftermarket HX is available.

Even the aftermarket HX is $500.

But as I stated, I really just want a temp fix to make sure the HX was the only place I was getting salt water intrusion into coolant. Because if the manifold ($700+) has a leak too, then I'm just gonna buy a portable gas unit and be done with westerbeke.
 
Can you bypass or plug the HX and do a pressure test (drop test) the rest of the system?
 
Can you bypass or plug the HX and do a pressure test (drop test) the rest of the system?

Well I have salt crust accumulating underneath coolant pump and around coolant cap on manifold. So not sure I could make a strong conclusion just by pressure testing because could just leak thru there.

Obviously system is being overpressurized, correct? However, the salt in system is clogging the manifold outlet to the expansion tank -- would that cause enough pressure to push leaks out the cap and pump?

If I'm lucky, thats all it is. The oil looks fine. But Im hesitant to buy any expensive parts, until I can be confident it's just the HX.
 
Even the aftermarket HX is $500.

But as I stated, I really just want a temp fix to make sure the HX was the only place I was getting salt water intrusion into coolant. Because if the manifold ($700+) has a leak too, then I'm just gonna buy a portable gas unit and be done with westerbeke.
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I'm fairly certain a manifold leak could not allow seawater into your coolant. From what you are describing, it sounds like your coolant is mostly seawater.

Dont be a cheap-skate. Just replace the HX.:)


On a side note, I know that if one of the rubber couplings on my northern lights lights generator HX failed, I might get sea-water in the coolant.
 
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Remove and take it to Local radiator shop, inside the boat buck add on.
 
You say the system is getting over pressurized. If this is occurring from the seawater side you have a blockage. If it is on the fresh water side you have a bad cap. I'm not sure that it is over pressure but those would be the two causes.

Note that when the engine is first started the sea water side has higher pressure. When the engine begins to warm up the fresh water side has higher pressure. If there is a leak the sea water will push into the fresh water system at startup and the fresh water will push out after shutdown.

Also note that a leak in the heat exchanger core usually means metal has been lost to corrosion. So one leak usually means there are more just about to happen. For both of those reasons stop leak is not likely to work for any length of time.
 
You say the system is getting over pressurized. If this is occurring from the seawater side you have a blockage. If it is on the fresh water side you have a bad cap. I'm not sure that it is over pressure but those would be the two causes.

Note that when the engine is first started the sea water side has higher pressure. When the engine begins to warm up the fresh water side has higher pressure. If there is a leak the sea water will push into the fresh water system at startup and the fresh water will push out after shutdown.

Also note that a leak in the heat exchanger core usually means metal has been lost to corrosion. So one leak usually means there are more just about to happen. For both of those reasons stop leak is not likely to work for any length of time.

Yes I guess my main concern is what is causing enough pressure to push coolant out the cap and pump?

Im just afraid I have a leak in the manifold too. Not as a source of sea water, but the source of the excess pressure. But like I said, it could maybe be a simple as salt crust blocking the outlet to the expansion tank...
 
Run the generator up to temp with the cap off. Look for bubbles. Bubbles mean exhaust gases are getting in.

Second check: NOTE HOT!! Then install the cap. The seawater pump does not create enough pressure to overcome the cap. If you are still pushing water out you probably have a bad head gasket.
 
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