Lehman 135 Heat Exchanger

We just had our Albin 40 with twin 135 Lehmans bottom painted. Just prior to launching, we noticed antifreeze leaking through the engine seawater strainer. When the boat was in the sling, it was impossibe to check the coolant reservoir, but when we were set afloat, I poured 2 gallons of water into the reservoir, which quickly disappeared.

My question is has my Heat Exchanger given up the ghost? The boat was poorly maintained by the previous owner, and it appears that the heat exchangers were original equiptment, but when I checked the zincs they seemed to be functioning.

Encore is now 32 years old, and I'm pretty sure that it's time to change. Has anyone else had a similar experience?

Note: I changed both transmission and oil cooling heat exchangers when we bought the boat, but the engines were running at a cool 165 degrees, so I didn't change the main H.E.

Thanks,
Jim
Encore
Albin 40

sounds like the heat exchanger . pull the ends off . make sure your not fulling your muffler with water. stop poring in water until you remove the end plates.there should be no path out from the res when the plates are off. if water you poor in comes out the ends of the tubes the exchanger is bad.

You could check them by removing them and taking to a radiator shop and pressure checking. They will connect a air hose to it and submerge in a tank to check for air bubbles.

I didn't start the engine, and when I poured the water in, I heard it 'gurgle' out thru the strainer and seacock.

i must be a big hole . i would drain the muffler also turn the engine by hand before starting. the impeller must be worn out also.

I'm heading up the marina shortly, I'll pull the end caps off, but the impeller was just changed recently. The engine hasn't been run in 6 weeks, and ran perfectly when (I guess till)we got to the Marina. We left it overnight and pulled it out the next morning and it was still running cool. I guess it just 'expired', sort of a last breath. I'll keep you updated on progress tonight when I get back from the marina.

Are you saying your heat exchangers are 32 years old? If so, they should be changed as a matter of course. Thirty-two years is way past time to replace. The problem I have with a pressure test at a radiator shop is the unit may test okay but be on the very edge of letting go which will not be revealed by means of the test.

if antifreeze is coming out your sea strainer , the only place it could be coming from would be the HX. If you are not aware of them being replaced , replace them. They are cheap as far as boating parts are concerned. (ask any volvo penta owner how much their HX's are). And buy the copper-nickel ones as they will work better and last longer.

I agree with the above comments. Have you talked to Brian at American Diesel? If not then you should as he will be a great resource.

Those engines hold 5 gallons of anti freeze. Being able to pour in 2 gallons means it’s leaking down a LOT. You should not run the engine again until you resolve the issue because you could overheat it.

I also question how easily the antifreeze backflows through the pump and out the (presumably) intake seacock. 1, water shouldn’t be able to back flow through a good pump. You may have missing vanes on the pump impeller.. 2, isn’t there a sea strainer between the seacock and pump? If so, you should see antifreeze in there too.

Once you resolve this antifreeze loss issue, get a hand held IR thermal gun and check the engine temp directly under the header tank (this is where the thermostat is) and verify temps. 165 for coolant temp is too low but it may very well be related to your known issue or could be a gauge problem.

Ken

Ken,
Just changed the impeller about 20 hours ago, but I'll check it again. I've got a new HX coming on Tuesday. There was antifreeze running out the sea strainer, when Encore was in the sling. We ran home on one engine, about 3 hours, but now that Encore is home, I can start to troubleshoot. I'll keep the Forum updated on progress, or lack of, that I have.

VJameslanza said:

Ken,
Just changed the impeller about 20 hours ago, but I'll check it again. I've got a new HX coming on Tuesday. There was antifreeze running out the sea strainer, when Encore was in the sling. We ran home on one engine, about 3 hours, but now that Encore is home, I can start to troubleshoot. I'll keep the Forum updated on progress, or lack of, that I have.

Click to expand...

Pardon my surprise, but you ordered just one heat exchanger?!!! Without question both should be replaced. One failed. It would hardly be a surprise if the other one failed soon. This is not a situation that one should take chances.