Aargh. Low Compression???

[TCluff]

popping thru the intake leads me to believe cylinder pressure is bleeding over or back thru an intake valve. That is why I was thinking a headgasket or valve issue

ME TOO

 

[lmills]

Just to let everyone know. . it was my headgasket. Dave at pdr thinks its because of the backpressure issue on bd twins. im so ******. 2nd headgasket. my r49 is set at 1250. . like wtf.

I would hardly think it would be that, but it's possible. A lot of guys have ran them with good luck.

 

[getblown5.9]

i know this thread is old but it stinks that it was a headgasket. i had that same noise a week after doing my marine gasket, o-rings, and studs... turned out to be a bent pushrod.

when i reset the valves one of them wasnt all the way down in the lifter, and it popped up and bent. no ill effects after replacing the pushrod and the truck runs great now and even made 500/1021 on the dyno a month later

 

[CStraface]

I'm would have to probably agree with Loyd and Justin on this one.

It sounds like an issue with something sealing in the head area (valve, seat, bad crack, gasket). But, for peace of mind: take off your oil fill cap with the truck running and report back. Should you have little puffs of smoke coming out, then that could indicate something like a bad ring, piston, severely scuffed wall, etc...



Let us know, we're all here to try and help.



~Wes~

After running truck temp up to operating temperature, then shutting her down once egt reaches 350*, should white smoke be comming out of the oil fill hole?

 

[crawler]

After running truck temp up to operating temperature, then shutting her down once egt reaches 350*, should white smoke be comming out of the oil fill hole?

I've some trucks that run perfectly fine do that.



However the question is: How much white smoke is coming out?



~Wes~

 

[CStraface]

It was just 2 or 3 seconds or puffs and then it stopped.