Engine/Transmission (1998.5 - 2002) More Hard Starting

[ryecreek]

Have a 2000 it will sometime start fine sometimes go 5 or more rev before kicking. been through all the posts and tried everything except the clear hose filter-vp. even the return overflow so now now what? here is more info:



LP in factory location and a big line kit with a second pump from diesel dynamics was installed about 1. 5 years ago (that's when i noticed the longer crank) BTW I have not really drove the truck much till a week ago hence the long term prob.



pressure at the vp 26psi not started pumps cycling pumps stop and prussure falls to 0psi in @2-3sec. ??normal?? I assume it is with the small hole in the return overflow or was blowing in the wrong place??



i read too that the vp doesn't like high pressure could it be that?



can i disconnet the return and supply at the tank and vacuum or pressure test the two is that safe on the pumps and the vp.



could the fitting at the tank be leaking after 320K of rough dirt roads? any way to test it?

 

[Tiger Rag]

Sounds like you need a Bosch relay to cut the pusher on after the truck starts. You may try and call BD directly and buy their oil pressure switch which cuts the pusher on after the engine gets oil pressure. BD's kit is what I'm using for my pusher set up and I have no hard start issues. Many others have used the Bosch relay switch to effectively do the same thing.



Good luck, Matt

 

[ryecreek]

I turn off the pusher and try it didn't know such a thing existed thanks

 

[johncameron]

My truck had a hard start after my FASS install. About 3 months after the FASS my VP went south. Since the VP change I havn't had 1 hard start. I hope you VP is not going.....

 

[ryecreek]

me too thats what i'm affraid of i just replaced the vp at 280K (first one if ya can believe that)

 

[ryecreek]

Pusher off same issue

Anybody have any thought on pressure or vacuum testing lines at the tank w/supply and return disconnected

oh heard mention of a check valve at filter housing true/false if so is at at the banjo?????

what about the pressure bleed down after the pump cycle???

man this thing is pissin me off

 

[DavidC]

Pusher off same issue

Anybody have any thought on pressure or vacuum testing lines at the tank w/supply and return disconnected

oh heard mention of a check valve at filter housing true/false if so is at at the banjo?????

what about the pressure bleed down after the pump cycle???

man this thing is pissin me off

The check valve you are referring to I believe is also known as the overflow valve. It is mounted on the VP44 with a return line to the tank. It is supposedly factory set at 14psi to open and reroute excessive fuel/pressure back to the tank. And yes the overflow valve has a banjo. I believe the pressure drop off is normal when the lift pump shuts off as there is no check valve in the supply line so when the pump turns off the pressure goes away. It could be that running that high of pressure to the VP may have ruptured something in the VP. If that finally is the case then I would put a regulator on that system to cut down on the high pressure.



Dave

 

[ryecreek]

thank you

the overflow has been replaced and that answers that hope the vp is ok

 

[sstockton]

I don't know if this is anything or nothing, or something that everyone knows about. But I've heard that if the Diaphram in the VP is exposed to below 5psi, it can move up 4x farther than it is supposed to resulting in cracks. I guess this is a metering diaphram that would route excess pressure back through the return line. According to what I read on DPP's website the cracks can result in hard starting when subject to high pressure(even from a stock lift pump). Anyways, I was having a problem like this, and just installed a oil pressure switch Honeywell-Hobbs PN#78575 or 78143 will work. Worked like a champ haven't had any problem since. I'd say its worth a shot. Not a very difficult job.

Sean

 

[ryecreek]

Appears fixed Oo.

I istalled a bypass around the pusher

which lowered my psi alittle too(19PSI)

but it starting fine now hot, cold and anything in between

thank you everybody

 

[LowFly]

ALSO..... this has been brought up to me... ... Get a simple reflash at your delaer, OR find someone with Marco's Smarty. This has been known to clear up hard starts with the FASS. The Smarty has the Latest and Greatest from DC in its tunes... and even if you go back to stock... . it will flash the Latest DC updates on your ECM... . plus enable your high idle. This Smarty is smarter than i thought!