Compression 150 HPDI's

[edc1213]

I have 2 2001's 150 HPDI's which I'm trying to sell. One has all 6 clyinders at 100 PSI and the other all six are 90 PSI. Both motors were and had been running great when removed from my boat with 1200 hours total time. The mechanic at the dealership said there is lots of life left in the engines. Should the compression be of concern to a buyer? I did have one guy back out saying the compression was too low. I always thought if compression in all cylinders the same you are ok, its when one or two cylinders are way off from the others that there is a problem. What should I do to help get the motors sold?

 

[micel]

Re: Compression 150 HPDI's

I have a '97 dt150 and tech's say the same thing.Alot also has to do with which guage calibration, engine warm or cold,chamber wet or dry.Mine varies from 95 to 115.Actually a lower compression engine will last longer b/c of less pressure on bearings,but the down side is performance(fuel economy and power).If you really want to raise compression you could mill heads .o2 to .o4 this would raise it 15 to 30 points or use a thinner head gasket.I would advise against both,just be truthful and advise prospective buyer what your tech has said.These sound like well maintained high hour engines that have alot of life left.I would not take less than 4000 for both with controls.

 

[yamamarinetech40]

Re: Compression 150 HPDI's

edc, your compression is actually very good for an HPDI, as these are low compression engines....the 200 actually is specified at 68 psi minimum....pretty low, but that's how she works...
oh, and micel, yours is just barely in spec....