LB7 cranks a LONG time before starting

[dscluchfc]

The dealership, Scoggin Dickey in Lubbock TX just replaced my injectors and injector pump, on the LB7 that has 232,000 miles on it due to the dreaded while cloud in exhaust at idle. Four injectors 1,8,6, & 7 were bad, and upon inspection, the rail showed possible metal contamination possibly from the CP3, so it was replaced as well because I am back in for repairs now after having the injectors done at 186,000 miles. 46,000 on a set is not good, IMO.

Prior to the work being done, you could turn the key to start and about two turns of the motor and it started....rer, rer start...it has always been like that.

Now with the new injectors and injector pump, turn the key and it turns over for about 10 seconds before starting.
rer rer rer rer...ad naseaum for up to 15 seconds, then start...
after starting it runs fine going down the road.
They warned me it was taking longer to start and said it was probably "air" in the fuel lines someplace that would work its way out.
Further, I now have some surge at idle....not so much noticeable on the tach but to the ear it is quite noticeable.

Not so sure I buy that "air" excuse for the slow start...and I don't know about the surging at all.

I am an insurance agent, not a mechanic at all....so, anyone here have a clue as to why it is so slow to start?
or why it now surges?

Thanks for your input!

[Kennedy]

I would suggest adding a lift pump for starters as this will ensure that there are no "air" issues and also help the longevity of the fuel system. I'd also suggest that you read this:

http://www.kennedydiesel.com/docs/Duramax%20Injector%20Failures.pdf

[dscluchfc]

Diagnosed and fixed.
Bad rubber hose connection not tight between fuel filter and CP3 allowing the bleed back to occur.
Just to be safe rubber hose was replaced. Now behaves perfectly. :D