HDJ81 - no fuel when cold

[Greg_B]

Tapage, you want a low pressure pump. Don't hit the backside of the injection pump with too much. 2lbs or so after whatever filtration you are using is what I understand, thought I know folks who run the FRB-5 with no reducer.

FRB-2 for the 24V folks.

hth's

gb

 

[Tapage]

Thanks Greg ..

I'm using something like this one in my Tencha ..

eBay Motors: ELECTRIC FUEL PUMP UNIVERSAL IN LINE 30gph 2.5- 4psi (item 250341797367 end time Jan-10-09 19:37:09 PST)

seems to be right in PSI .. and what about hte flow rate .. ?

 

[finderscuba]

Couple additional questions:
-should the priming button be really hard to push when cold? Mine won't budge when below about -23°C. I have to warm it up before I can pump at all. Does this indicate that the primer might have some moisture in it and could be blocking or impeding fuel flow? Or letting in air?

-without buying an inline filter, how else can I diagnose the filter/primer assembly? If I remove it, can I disassemble and clean inside?

The truck seems to work differently in different weather:
-above freezing it starts fine with minimal/no glow and minimal cranking
-0 to -15 it will start but needs a bit more cranking
--15 to -23 it needs lots of glow and has to crank quite a bit or have to work primer for a while
-below -25 and it won't start without tons of cranking and a dual-boost (2 batteries) as they will crap out with the glowing and cranking. I usually have to heat up the primer assembly to pump it a bit too.

Once the truck has run, I can leave it most of the day and it will fire up with only a few seconds of glow and minimal cranking. It's just that overnight sitting that's causing the grief.

This morning it was -33°C - I didn't even bother trying to start it. Yesterday it wouldn't go when it was -27°C out. We're stuck in another cold snap so I won't be working on it until it goes above -20.

If I disconnected the fuel hose from the IP side of the filter, placed the end in a container of diesel and then cranked, it should start right up even if the fuel hose was empty? If so, this would indicate that the air leak is filter and/or filter to tank, which I'm almost positive it is. Are there any clamps to change between the firewall and the tank?

 

[70sguy]

Here is a pic of your fuel supply and return.
Can't say what the primer should feel like at those type of temps..don't see below -10c here.
Did you swap in a clear piece of hose between IP and primer/filter yet?

Starting the engine on a jar of diesel at the IP will likely confirm what you already know... that you
have a problem getting fuel out of the tank, however it won't indicate whether the
problem is due to air being sucked in somewhere or whether the feed pump in the IP is just not up to
the task of pulling the cold (thicker) fuel all the way up from the tank.

The clear fuel line will tell you if you are getting air in somewhere. So get down to the pet store and buy
a piece. 10mm ID Yes, the IP should pull the fuel in even if the clear hose has not fuel in it. If you can get it to gravity feed all the better.

If you want to rule out the Primer/Filter, swap in a piece of clear hose long enough to go from the end of the main hard line directly to the Injection pump, bypassing the Primer/filter assy all together. Not a safe long term solution but OK for a quick trouble shoot...the trick is stopping the fuel from sliding back into the tank while you swap the line in... small vice grip to pinch off the rubber hose between the tank and main hard line should do.

IMO it is evident that the fuel feed pump built into the VE type injection pump on the 1HD-T is marginal
at the best of times, let alone when it is -33c. I am a believer in adding a low PSI lift pump (Walbro 6065/FRB-5) between the tank and main hard line.

 

[finderscuba]

Can I install a fuel pump such as a Walbro FRD in the engine bay near the fuel filter? Can it pull the fuel from the tank? Or does it have to be installed at the tank to push the fuel?

I was recently quoted $230 plus shipping for a new OEM filter cap. Throwing a $100 fuel pump on seems quick and relatively inexpensive. This is especially true when I'm not even sure the filter cap is the problem.

Also, where is the water separator on an HDJ81? I have yet to see one anywhere on my rig. Is this built into the fuel filter?

 

[roscoFJ73]

Couple additional questions:
-should the priming button be really hard to push when cold? Mine won't budge when below about -23°C. I have to warm it up before I can pump at all. Does this indicate that the primer might have some moisture in it and could be blocking or impeding fuel flow? Or letting in air?

Its designed to pump fuel and push the air out with the fuel line disconnected at the inj pump or primer pump outlet.
If the fuel lines are still connected it is straining the primer and the cold fuel makes it worse.