MapisM
Well-Known Member
PF, I don't know what engine version shows your pic, but not the LE403 which was being debated, anyhow.
It might be the previous LE401 (680hp), but I'm not sure.
Different animal anyhow, because the differences don't end with the pneumatic valve for sea water.
In the pic below, which definitely shows a LE403 engine, I highlighted in orange that valve.
Now, also assuming that it can be removed and replaced with a plain tube, as in your pic, there are other relevant differences:
Firstly, the yellow part shows the connection to the closed cooling circuit (completely missing in your pic), with a different side cover of the HE.
But most importantly, the whole aftercooler in you pic is bound to be different, i.e. NOT split into two section (raw water+cooling liquid), and all cooled by sea water instead.
All well and good, mind. But that sounds like a helluva Heath Robinson modification.
In fact, to my knowledge, the recommended MAN solution for bypassing the LE403 valve (i.e. leave it permanently open) was to remove only the small tube connected to the aftercooler for opening the valve when the air intake is pressurized, replace it (on the valve side) with a screw just long enough to keep the valve fully open, and close the opening on the CAC side with another short screw,
A solution which, aside from being much simpler, allows to keep the intercooler split in two sections, which still has its raison d'être also when sea water flow is not restricted anymore, for a faster engine warm-up.
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