97 12 valve skipping HELP!!!!

[mudnyeri]

just bought a 97 3500 12 valve . Skipping on # 3 cyl. just replaced injector , still the same. valve spring looks good. i know some of yall have seen this before, please help

 

[argve]

Check the barrel on the injection pump for leaks or leaks on the line going to the injector... I had one once that missing slightly and found that the barrel was leaking.... ended up all I had to do was tighten it down - your's maynot be so simple.... but it's worth a look see.

you can also swap the delivery valve between two barrels to see if the problem follows.

 

[mudnyeri]

would i still have fuel at the injector line??

 

[kas83]

would i still have fuel at the injector line??

Yes, but the pressure would be lower than normal, and not be able to pop the injector, if a barrel or dv holder were the culprit.

 

[BigRigTech]

I've seen the same thing, it was usually a bad injector or a delivery valve in the pump....We chased one for a week, had the p-pump off twice before we discovered the new injector was bad too...

 

[mudnyeri]

thanks , gonna tear into it , let yall know what i find.

 

[mudnyeri]

well swapped #3 and #1 dv , the skip stayed on #3. whats next to check?? could the pump be bad just on #3 ??

 

[Whit]

swap injectors now and see

 

[mudnyeri]

well it wasnt a fuel problem... bad intake valve, thanks for the help.

 

[mudnyeri]

oh well head is off . valves look good , gonna check head for cracks. no fire in #3 cyl . whats the best inj. pump for the money ? BD Diesel?

 

[mudnyeri]

ok status report. head is off had it checked, all is good.. pump off and sent to shop. got it back, pressure and all is good, what else could it be???

 

[BigRigTech]

Have you had a good look at the camshaft lobes? I've seen some 12V's eat camshafts over and over - don't ask me why....I've been dooped by wrecked cam lobes myself when looking for a miss....Detroit 60 series engines are famous for it with there ceramic followers.