my uhaul pump won't start when hot

[damac]

I have been searching and reading and was just wondering if this always means a bad pump like I see mentioned too often?

I was just wondering if their pumps sat in their shrink wrap which wasn't air tight, and I only got a dribble of fuel when I installed it, could it be things sticking?

Could I try an atf soak for a day and see if something frees up or do I need to setup a return with them right away?


Truck starts right up when cold even with some air intrusion, seems to run pretty good with initial timing. Truck has fuel when warm and the starter is spinning over even faster when warm. You can just tell it doesn't want to even try to start until its cooled down.

 

[rhkcommander]

Pour some cold water on the pump and if it fires then it's some internal sealing or some such and I would return it. Pretty standard test on old pumps to see of their shot.

In any event good luck.

 

[Cincinnati Guy]

Possibly the pump sat on the shelf long enough to gum up the internals a little. Fill the pump up with some injector cleaner. Let it sit a good while.

 

[towcat]

Pour some cold water on the pump and if it fires then it's some internal sealing or some such and I would return it. Pretty standard test on old pumps to see of their shot.

In any event good luck.

VERY VERY VERY BAD IDEA FOR A REBUILT PUMP.
this trick is only for pumps nearing death.
ATF is a poor choice but better than none.
"sea foam" mixed with ATF is a better idea.
Stadyne pump lube used straight with no dilution is the best. but most expensive.
there's also no warranty on these pumps iirc.

 

[Cincinnati Guy]

I agree with towkitty, the water idea is a end of life procedure to get a little bit time out of it. Just try your favorite injector cleaner then get back with us. Also your timing will greatly affect on how easily it will start. Is it timed with a timing meter or just by ear?

 

[Diesel JD]

I think it's probably a heat sink problem. I'd never suggest pouring water on any IP that is under warranty without the builder's permission otherwise the warranty might be void. If there is no warranty you might try some lukewarm water poured over it next time it acts up. It would be better to try the lubricity formula or seafoam first to see if something is sticking, but this has all the signs of a bad hydraulic head. Had that in a couple of rebuilt pumps....even good builders build a few like that, average builder build a few more and hacks build quite a few. Not sure where the Uhaul pumps fall on that spectrum.

 

[OLDBULL8]

Put a clear line on from the IP to the filter, see if you have air intrusion, lots of bubbles back to the filter. Jumper the starter solenoid with a screw driver so you can see what 's happening.

 

[typ4]

The uhaul pumps are no return , they are a liquidation item.
What is happening is your head and rotor in the pump is right on the edge of tolerance, when the fuel is hot it cant make enough pressure to start, the cool water shrinks it so it will build the pressure, but ot can also sieze the pump, head and rotor assemblies are 800, so I would buy some cheap pumps and hope.

 

[damac]

I have the pump timed just a tad advanced over the stock marks as a starting point. It was actually spitting out a little white when on the throttle. I advanced it a touch more and allot of that went away. The engine runs smooth but I get no hint of a rattle even with the cold advance so I have been wondering if it could be a timing thing?

Right now when I make these fine adjustments though I really am not seeing any difference. The truck still leaves a faint trail of black smoke when stabbing the pedal. When just idling or cruising at steady pedal there is no haze. Not hearing any hint of injector rattle.

As far as not being able to return a uhaul pump, we purchased it through ebay and its not listed as for parts, but being refurbished to like new condition. So we should be protected by ebay buyer protection I would think? If you aren't willling to have an item delivered as listed then you need to list it as for parts only or core.

 

[Cincinnati Guy]

IM sure if you get the right person who we on oilburners usually deal with on uhaul im sure you two could work out something. Whats his name and addrrss guys?

 

[rhkcommander]

His name is Frank, i forget the details.

Sorry for the suggestion, another one'r my SWAGs. I know its how we test an old pump. Hot metal and cold anything dont mix too well

These pumps AFAIK were just sitting on shelves, possibly for a good while. If there was a warranty then you'd have to see when they were rebuilt, see if they will honor it for YOU rather than u-haul, etc. Thats generally how returns work in my experience but sometimes automotive returns go differently

Ebay buyer protection if the add listed it will likely cover you but no promises...

 

[OLDBULL8]

Was it rebuilt by DieseLogic? That name will be on the tag in place of the Stanadyne tag. It may have a date code on it. I bought seven of them, sold three and no report back with any troubles.

 

[typ4]

The ebay ad says no return, I know if someone ****** off uhaul we will not get anymore deals from them.
They are advertising as a rebuilt because thats what they were when they were using them.
My price on a STOCK rebuild is now 480.00, 2 something is a decent price, YEs it should work but this condition is rare, the last bad head/rotor/ I had the shop had 2 run it for 3 hours to get it to mess up.

 

[damac]

Ok is it possible I am jumping the gun here and timing is effecting a hot start?

I ask because as I am advancing the pump it seems to be getting better?

Took the truck for another run with another hint of advance. Came back and shut it off and it starts after about 3 seconds of turning over. Did that a few times in a row. Then went shopping and came out 20 minutes later and it started. Then came home and came out 20 minutes later and it started again.

Starter still seems to spin over what I would call its fastest, when hot like that. No change in smoke patterns that I could see, but I would say there was a tad bit more noise detected through the cowl intake at speed? Still can't detect the start of knocking with the injectors.

I think I took for granted how easy it was to get my old vw jetta within range by ear. Perhaps I need to start at square one with the timing and revisit the smoke patterns later?

Does anybody rent the tools to do this job on the forum? Would pay deposit plus rental fee, that is if a newbie can follow directions on using them.

thanks for any info!

 

[1994Diesel]

Ok is it possible I am jumping the gun here and timing is effecting a hot start?

I ask because as I am advancing the pump it seems to be getting better?

Took the truck for another run with another hint of advance. Came back and shut it off and it starts after about 3 seconds of turning over. Did that a few times in a row. Then went shopping and came out 20 minutes later and it started. Then came home and came out 20 minutes later and it started again.

Starter still seems to spin over what I would call its fastest, when hot like that. No change in smoke patterns that I could see, but I would say there was a tad bit more noise detected through the cowl intake at speed? Still can't detect the start of knocking with the injectors.

I think I took for granted how easy it was to get my old vw jetta within range by ear. Perhaps I need to start at square one with the timing and revisit the smoke patterns later?

Does anybody rent the tools to do this job on the forum? Would pay deposit plus rental fee, that is if a newbie can follow directions on using them.

thanks for any info!

Have you tried what oldbull8 suggested?

Put a clear line on from the IP to the filter, see if you have air intrusion, lots of bubbles back to the filter. Jumper the starter solenoid with a screw driver so you can see what 's happening.