Sealife
Guru
So after a 50+ hr run at 2000 RPM (I usually run at 1600), I noticed slight discoloration of paint at elbow from cylinder into exhaust manifold on cylinder 6. Upon further investigating at various RPMs the EGT varies between cylinders but is consistant in the ratio of tempurature variance thru the RPM band. Cylinder 2 is always coolest, cylinder 6 is always hottest, the others fall in between. The concern is that at 1800 RPM (highest tested) #2 is 245 deg F, and #6 is 315 deg F. This is more of a delta T then I would prefer. I assume the jerk injection pump plungers are injecting different amount of fuel per cylinder with the hottest being a richer mixture. I am doubting injector or valve adj., but they are easily checked.
At what temp does the exhaust valve become a concern? Obviously #6 temps are always a concern in this motor anyway. I know these are low tech motors, but still would like to be proactive as we have no back up propulsion and will be leaving Mexico for Pananama in Spring. Those of you not familiar with our blog, should note tis is a Bowmac Reman motor now with 430hrs. So also may still be breaking in...
Thanks,
Scott
At what temp does the exhaust valve become a concern? Obviously #6 temps are always a concern in this motor anyway. I know these are low tech motors, but still would like to be proactive as we have no back up propulsion and will be leaving Mexico for Pananama in Spring. Those of you not familiar with our blog, should note tis is a Bowmac Reman motor now with 430hrs. So also may still be breaking in...
Thanks,
Scott