Priming Pump only Pumps Fuel from body--not from bleed valve (3B engine)

[Diescipel]

Hey guys,

Replaced the fuel filter and as stated in title the priming pump leaks/pumps fuel out of the cylindrical body of the pump itself and I get no pressure/fuel etc. up at the bleed valve. Obviously this is not normal and I assume there's a bad seal in there. I had noticed it was a little wet down there but this is the first time I've tried to bleed the fuel system/use the priming pump.

What are the consequences of trying to start the engine with air in the system?

TIA

B

 

[fjbj40]

take filter off , fill with CLEAN fuel , put back on and start , she may buck and fart and stall several times but will self bleed . Not the best way to do it but will get you out of jamb . Sounds like you need new primer pump .
Daryl

 

[beanz2]

Yep, a new primer pump. Call your local Denso dealer for part number 092130-0220. About $30 IIRC. I got mine from Diamond Diesel in Oakland, CA (510) 532-8500. They would ship too.

Dave

 

[cruiser_guy]

If you've tried starting it with air in there you could have a real problem. You might try cracking the injection lines at the injectors if you've tried starting without priming. I hope you've got a vehicle capable of jumping you nearby!!

 

[Diescipel]

Okay, started fine. I mean, yeah, needed a several cranks, but once I learned to keep the throttle open, it was really no big deal. I now have lots of confidence in my starter and batteries! lol Seemed to run fine after a while--idle great, power same as before. Do I still need to crack the injectors?

BTW, if I ever do need to jump this 24v beast, don't I need two 12v vehicles? And that would mean two sets of cables.

Thanks for everybody's help, especially beanz/Dave's part # and phone number! You make it too easy.


B

 

[cruiser_guy]

If it's running fine and not missing or stumbling you're OK. If it's running rough or stumbling crack the injectors while it's running. Do one injector at a time and only turn the nut a turn or two DON'T remove it all the way (deisel fuel under 1700psi pressure can injure you).

 

[dieselbigot]

BTW, if I ever do need to jump this 24v beast, don't I need two 12v vehicles? And that would mean two sets of cables.

9 times out of 10, if you need to jump your 24v rig, it will be because of a depleted 12v side battery....just hook your jump vehicle up to your 12v side battery and you should be good to go....again, 9 times out of 10

 

[Diescipel]

"Side Battery"? Sorry, haven't even looked at the electricals yet. I assume that the draw for the 24v system is off of one battery, but the "side battery" is just wired to it in series?

B

 

[waaz]

Hello
Every time you change the fuel filter, have the new one filled with clean diesel fuel and swap right away. This is the best way to change a fuel filter. Same for water seperator filters. The primer pump should only be used when there is no other option.

 

[lowenbrau]

The primer pump should only be used when there is no other option.

I have to ask why you think this.

 

[Diescipel]

FSM says to pump it, but doesn't say anything about filling with clean fuel. ??

B

 

[beanz2]

I've replaced the primer without filling it up with diesel first. It just takes more pumps to get the air out .

Dave

 

[Diescipel]

Makes sense. BTW Dave I called Diamond Diesel and got the pump shipped today--$21.60 before shipping and tax. Thanks.

B

 

[waaz]

To Lowenbrau
Think about it, it does not take a rocket scientist to to figuire that out. Much easier on the batts and starter. If you change the fuel filter with one that it primed with clean diesel fuel, no need to bleed air

 

[waaz]

Also one to add. The primer pump should only be used when you run out of fuel and you cant get the fuel filter off to prime. ( Yes the old filter can be primed if you run out of fuel) The primer pump is only ment for emergengy priming.

 

[burger]

Why then would the FSM tell yo to use the priming pump when changing the filter? Hmm sound fishy. What exactly is "emergency priming". Also how is not using the priming pump easier on the batts and starter. I would think that if you were not priming the system then you might have to crank longer to get the air out. Seems like that would cause alot more wear than moving a plastic piston up and down.

 

[Diescipel]

I got the new primer pump today and will install tomorrow--do I then have to bleed the system again with the new pump? I assume yes, air will get in the system when I R&R the pumps.

B

 

[burger]

I would think so. Just crack the bleeder an bleed it to there.

 

[lowenbrau]

Also one to add. The primer pump should only be used when you run out of fuel and you cant get the fuel filter off to prime. ( Yes the old filter can be primed if you run out of fuel) The primer pump is only ment for emergengy priming.

Much like the bottle jack is only meant for emergency lifting of the vehicle. The only reason to pre-fill the filter is to save time and frankly I don't think its worth the risk of contamination. The hand primer will pump hundreds of gallons of fuel in its lifetime if you need it to and the reason most leak is due to lack of use. If you do end up with a leaky one, it costs less than $50 and three minutes to replace it.