Looking for Lehman inner coolers

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Detroito91

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After servicing the turbos it was suggested to have the inner coolers serviced also. The repair facility did a great job in destroying my coolers. A second recommended facility said that they could not be saved. Replacement was the only answer!
I have a MT Tradewinds 43 with twin Lehman 275 turbo diesel engines. Looking for 2 inner coolers. Suggestions for possible sources will be appreciated.
 
I think they are obsolete. Mine are in good condition but I don’t need the 225 hp per engine so I bypassed mine while they are good. Some future owner may want the power so the aftercoolers can be reconnected and will work. It took about 20 minutes per engine and some 1 1/8” hose, if I remember correctly, to bypass them. I cut the tubes going in and out of the aftercoolers and then connected them with the 1 1/8” hose. I used a cushion clamp to hold the hose in place where it ran over the top of the aftercooler. Simple to do and simple to undo. To undo I would take a short section of the 1 1/8” hose and reconnect the cut off ends of the tubes and then put the rubber hose from the tubes back to the aftercooler. I don’t have an overall photo of the hose running over the aftercooler but if you want to see it I can take a photo tomorrow if I remember it...
 

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American Diesel should have some ideas
 
If you have Lehman 225's you can by pass the inner coolers, but not on the 275. Per Brian at American diesel. If anyone is looking for inner coolers contact Greg at bomac marine in Georgia. 954.766.2625. Very knowledgeable as is Brian at American diesel
 
If you bypass you intercooler, you will likely lose some power at the upper end. It might not make much difference at low power settings.

I wouldn't think that intake air temps coming directly off the turbo would damage the engine... Plenty of turbo diesels around that don't have intercoolers. Still, the guys at American Diesel would be the folks to ask :)

Hmm, on second thought, another possible downside to removing the intercooler occurs. The mechanical fuel injectors will be calibrated to work with the greater air charge that the intercooler gives you. So, especially at high power settings, you would likely be running pretty rich... possibly blowing smoke? I'm just swagging at this point. I would love to hear whether anyone who has done an intercooler-ectomy has experienced power loss and smoke...
 
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Bypassing the intercoolers on the sp275 requires a fuel metering change compared to the SP275.

As others have said, Brian should be able to help.
 
On the 225, all that needs to be done is run the hose around the intercooler. No changes to the injection pump or anything else, per Brian at American Diesel. The 275 is different though, so don’t do it on a 275.
 

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