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DarylB
07-02-2009, 09:45
My LBZ is losing prime. After a few hours of sitting still, it takes noticeably longer to crank. It will run for 2-3 seconds on a hill then die and will only start after priming. I've checked the bleed screw & O-ring on that, and it seems to be OK.

It was doing this before and after a recent filter change (just a few days ago). It's at the dealer now but they're diesel tech is out and I'm getting the run around (as usual, I hate the local dealer here). Anyone have suggestions? They said they would pull codes and it's been there almost 2 days.

DmaxMaverick
07-02-2009, 11:32
It's leaking, somewhere. Problem is finding it. Pressurizing the system can be a helpful tool. Check/replace the fuel filter (even if it's new), and check the water drain/WIF adapter. There's an O-ring on the adapter and the water drain valve (and they do loosen on their own--damn gremlins), or if it has a crack, will leak air. Replace the fuel filler cap (cheaper most of the time than wasting time checking it). If the vent isn't working properly, any possible leak will be exploited, even if it wouldn't leak otherwise.

DarylB
07-02-2009, 16:32
noticed a drip from the WIF sensor today. checked both o-rings on the filter. I Primed the pump w/o opneing the bleed screw and diesel poured out of the drain petcock on the WIF sensor. Is this normal? I dont' recall it doing that before.

DmaxMaverick
07-02-2009, 17:37
Nope. Not normal. Looks like you found your leak (or at least one of them). This can surely cause prime loss after shutdown, especially if the filler cap has a stuck vent (fuel/air contraction as it cools).

Remove the drain valve (it screws all the way out). Drain filter (just remove the top bleeder and catch the fuel). Clean and reinstall the drain with some grease smeared on the O-ring (dielectric or synthetic grease works well). No more than finger tight. Prime. Test again. If it still leaks, the WIF adapter may be cracked.

madmatt
07-02-2009, 18:06
fixed one today for this same issuse,, actually I've fixed 3-4 here in the last two months for this.. Buy a new WIF ($40 at the dealer IIRC) and put it on.

DarylB
07-03-2009, 12:07
Yeah I craked the old WIF yesterday. THe stealer stuck me for $78 + tax as that was the only dealer (40 miles away) that had one in stock. Going to run it abit today and check the new WIF. It appeared that the petcock o-ring was a little hard/contracted.

Rollingon
07-21-2009, 11:54
I've started to have similiar problems. Two weeks ago my 2002 started in the morning, then quit after 5-10 seconds, and wouldn't restart. It was towed to a reputable mechanic who poked around quite a bit, and changed the fuel filter, water sensor and fuel cap. It was fine for a few days, then the same thing happened, this time parked nose down. The first time had been with nose up. I discovered that 3 pumps on the primer (the first 2 had little resistance/pressure) got it going, so it was back to the mechanic. He called TAC, who agreed that it sounds like air in the lines, so the tech installed a clear line between the filter and FICM and ramped up fuel pressure. He started it several times over the next few days, it always started and he found nothing. The second morning I had it back - no start.

I've pressurized with the primer and inspected as closely as I can, from the fuel tank forward. No feel of fuel, nothing visual. This is our only transportation so it needs to be reliable. I've shown my wife how to pump the primer but she's not very happy about doing it if she gets stuck!

Any thoughts would be appreciated.