The motor still doesn't run good.We have put another head on one side,the
other was cracked but had it fixed.The truck still runs rough if you don't
unplug the fuel sensor.Has a light blue smoke comeing out pretty good.Still
losing water somewhere.Has blowby out of the pdr valve and dipstick.Fuel
leaking somewhere because there is smoke coming off the engine when it's
hot and runing.The oil pressure is about 40 and 20 idling.Thanks for any
Just some basics...
Sounds like both heads need to be removed (again) and remachined.
Compression ratios were over 21:1 on this motor so there is no room for
error in machining and reassembly. Poor cooling in pre-'97 units caused
burn-thru of the head gaskets in the rear cylinders. Next time around, fit
the '98-later high flow water pump with dual thermostats and crossover to
Rough running most likely from bad timing of the fuel injection pump when
re-mounted. You need to do a complete recalibration of the FI pump any time
you remove it or do anything that may alter it in any way. Also sounds like
the injection pump timing is off by at least one tooth on the gears and
chain. Common issue also was chain stretch so changing the FI pump timing
chain may be in order. Timing and calibrating the DS4 pump is something
best left to a professional with the proper tools - there is no "doing it by
sight and feel" with this pump as it's all electronic.
Smoke coming off the motor is most likely a leaking fuel injector line(s).
There are seals in each connection that should be replaced anytime the line
is disconnected or moved. The blow-by could be from bad timing at the
crank/cam, among other things.
On the positive side - your oil pressure is fine.
Cheers - Jonathan
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