1HZ Fuel Pump Issue?

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Apr 18, 2009
I'm having some issues trying to keep my truck running.
Recently put on a 12mm IP from XXI Industries.
Set to the correct plunger stroke given to me, new injectors (made sure to remove previous seats/washers and replace with new ones in the correct order)
New fuel filter and fuel line going from the hard line to the IP
Truck ran like a top for 1000kms, no overheating or excessive EGTs.

The other day going to work i noticed a loss in power, same thing on the way home.
Truck died in front of the house.

It has since got cold out. -4C
Replaced the fuel filter housing/filter to a racor 2 micron (Racor 400 series housing and R45s being the 2 micron filter). New rubber fuel lines from the hardline by the bell housing to the filter housing, and new line from the filter housing to the hardline on the firewall.
Still a running issue, basically need to rev it up to keep it running.
I got clear line today ran it to the filter housing and confirmed that I am not getting any air from the filter to the injection pump.

Brainstorming with a few people that maybe the 2 micron is too fine and to try the 10 micron filter (Racor R45T).

Still no difference. Having issues running. low RPM, if i was to raise the throttle and hold it at a set RPM it almost misses slightly.

Ideas? Did i get a dud of a fuel pump or am I jumping to conclusions?
I had a very similar problem with mine recently, I had leaned into the engine bay over the top of the fuel filter and squashed one of the tines of the original squeeze type hose clamps through my fuel line. Not enough to leak but the pump wouldn't stay primed because it was sucking air through the pinhole when under load. Food for thought. It's not always obvious. It was just lucky I spotted it as I would never have picked it up otherwise.
there is a clear line currently running from my new filter housing to the pump. When the air is purged out and running it/reving it for 5 mins there is no change. There is 100% air free fuel running into the pump.

I'm going to bypass the filter all together and run it out of a jerry can tomorrow.
I have a feeling this won't be the solution either.
any issue with a sticky fuel solenoid shut off? make sure power is there and constant maybe? Cold fuel may expain some of the issue but I'm not sure why the change...
No issues with fuel. I run antigel religiously.
Clear lines feeding the pump, no air, clean fuel.
Replaced return fuel lines at the pump to the hardline/injector overflow. No difference
Bypassed the filter completely and ran from a Jerry can with a clear line. No difference.
Though it could be a blocked line or pickup in the tank. I doubt it now after running from the jerry can.

Its the pump. Fxxx sakes seriously....
There is a buzzing from it at idle. It will go away when its rev'd past 2000rpm.
I have to keep the idle above 1000rpm to keep it running, drop it below that it surges a bit and just drops to below 600rpm.
It is EXTREMELY unlikely to be the pump. There's not much that can really go wrong there. And we do give a 2 year warranty. It will most likely be some silly problem somewhere. Just frustrating trying to find it.
Just threw you an email.
I am all ears.
Injection timing is on par with the specs you have provided.
Clean fuel feeding the pump and air free.

Its just weird how 1000kms in there is an issue.
You've had two different doctors renew your heart , sounds like if its not a loose stiicky sloppy injector you have a lung problem.
And you've ruled out all colder weather related issues.
i always carry starter fluid it works wonders in small doses for finding leaks you didn't think you had.
What does yotahead think it is,.
Did you get your injectors done at the same time.
Running the original turbo.
Any new vacuume lines or gauges.
what anti gell do you use and how much.
i run a quart of gas in my diesel i know from experience that it wont idle bellow 500 if i add to much.
It's missing slightly. It's like it's running on 5 cylinders.
Injectors came with the pump.
I made sure to remove all previous washers and seats, everything was put in extremely clean.
Yes same turbo from Graeme.
I have used diesel services 4+ premium polar for the last two or three winters with no issues along with 2 stroke oil. Put in 300ml per fill up of roughy 65litres (two stroke oil) the anti gel winter additive is only 30ml per fill up. Never had an issue with fuel freezing here. Never heard of it and I have asked a bunch. I fuel up constantly at the same spot for years, high traffic and it's dry.
Done everything yota has asked.

Everything I have done is pointing in a direction. s*** goes wrong, seems like XXi is willing to help.

I am all ears at this point and can do specific tests if asked. More than willing to troubleshoot.[/QUOTE]
You know we have not had a single issue with any of our pumps. All of sudden there is 1 with yours. I have it on good authority that you have pulled this pump down to check all the parts, thats warranty void right there. Never the less if it was put back together properly there still shouldn't be an issue. We give a 2 year warranty with them (twice as much as anywhere else). If you are convinced it is the pump, don't start pulling it apart. Send it back over.
Pump was not torn down. The aneroid pin top cover was removed and pin/spring/shims checked out (this you already know)
Top was reassembled the way it came apart and was bench tested so Foreal could get concrete numbers of what kind of fueling he could expect over stock with your pump.

Nothing else was tampered with.

You have on good authority what?

Why not just simply tell him to send it back to check what happened.
When someone tells me theres an issue with a pump Ive done, I ask what the symptoms are, and straight up say "send it back and Ill have a look."
Not once have I said "you mustve tampered with it, we don't make mistakes, We re THAT good".

Anyway, hope you can make good on what went wrong and rectify it. I know Foreal has put a lot of faith in your product.
So with all said , you three say its the pump. Doesnt sound concrete enough for me to jump on the pump. Shipping re and re down time.
What kind of turn around time and freight cost is that anyways ? Wouldn't you at least just get it bench tested before shipping back ?
Exactly where i would start and see what there breaking at and what the spray pattern looked like. Who knows you could be burning your piston too. Never did hear back if the pump uses the factory cam rollers.
So there are plenty of questions to be answered in the next little while.

XXi Pump Failure 1.jpg XXi Pump Failure 2.jpg

The pump after a HUGE headache fiasco is not going to Australia and is back in safe hands (Canadapost lost the parcel in Canada with pump and injectors on the way to Straya for 2.5 months)

Stay tuned on what is found.
kinda late to the " fest " but did you discard feeding problem ...? I mean feed your IP with electric pump help .?

judging by your post you already all over this .. I just wanna keep close to the KISS principle ..

keep us posted !

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