Fuel Surge

[ozy1]

I have a 91 mod td42,

when traveling uphills, i can feel the car jerkin about, i am assuming this is from fuel surge, any one had these troubles?

[JK]

How steep are the hills.

Is this on highway or offroad?

Is your fuel tank close to empty when this happens?

[ozy1]

well, tank can be at any level, on road, and can be from minor hills to heavy hills

[JK]

Sounds like a fuel line / pump problem rather than a "surging" problem not that I'm any expert.

[bogged]

Sounds like a fuel line / pump problem rather than a "surging" problem not that I'm any expert.

I was thinking the same thing but wasnt sure if I was imagining it.

Talkin to Awill4x4 about my fuel problems with a phukt BROWN DAVIS TANK, Andrew makes surge tanks for drag cars, and Gino mobiles... basically a tank that holds more fuel in it at the pump end, so it has less chance of getting air in it or not enough go juice.

Worth a thought

[Wendle]

take the truck to see a surgeon.
damn, that's funny

[ozy1]

i am going to see a diesel surgeon this morning, hoping that they are open, but ill wait and see what they say..

[bogged]

i am going to see a diesel surgeon this morning, hoping that they are open, but ill wait and see what they say..

what did they say, interested in this myself.

where did u go

[ozy1]

Went down to Nepean Diesel services, i think thats what its called, but found em closed, bummer, have to wait till during the week. will keep yas posted

[JK]

take the truck to see a surgeon.
damn, that's funny

You goose.

[Area54]

Let me guess, you have a jerking/shunting problem around the 1250-1500rpm, medium loaded hill? I have the same problem, pump has been rebuilt (due to water/fuel additive damage), new nozzles (age). I've checked the standard undamaged tank and pickup (clean and unblocked), put clear hose on all supply lines just before and after the factory fuel filter to check for air leaks (none found at idle or rev up) but obviously can't see them when driving around. I'm thinking of putting longer clear line through the cab for a test to see if there is an air leak when driving. I've got a feeling it might be leaking around the factory primer pump(92 model - seals might be getting a bit fragged) with delpi 296 filter adaptor (old lucas) or one of the lower hoses with a slow leak??? (no wetness though)

Surging/shunting was the same before and after the pump rebuild, and my fuel economy is poor by comparison to my mates rig with the same setup - wagon/tyre/ratio combo. still investigating (lots of time under rig with worklight)

[JK]

My engine has started running a little rough around the 2200 - 2500 range and also blows a bit of smoke if kept at these revs in 1st or 2nd gear. When I am driving along it feels a little like it is surging.

I spoke with my mechanic today and he advised that it could be one of two things...

1. Poor fuel quality. Run a couple of tanks thru it from another fuel supplier and see if it improves.

OR :arrow:

2. The injector pump is on it's way out. The cams in the pump do wear over time and cause uneven fuel supply to some of the cylinders so that some run leaner than others. He reckons this is common for 200,000+ ks without a rebuild and that I will be looking at $1,200 for a new pump He recommended that I also get the injectors done at the same time which would cost about another $240.

He has no interest in doing the work as he isn't a diesel mechanic and stands to make nothing out of my rig for this work. He is just a bloody good mechanic.

As you could probably guess... I wasn't too happy to hear this news

[Area54]

My engine has started running a little rough around the 2200 - 2500 range and also blows a bit of smoke if kept at these revs in 1st or 2nd gear. When I am driving along it feels a little like it is surging.

I spoke with my mechanic today and he advised that it could be one of two things...

1. Poor fuel quality. Run a couple of tanks thru it from another fuel supplier and see if it improves.

OR :arrow:

2. The injector pump is on it's way out. The cams in the pump do wear over time and cause uneven fuel supply to some of the cylinders so that some run leaner than others. He reckons this is common for 200,000+ ks without a rebuild and that I will be looking at $1,200 for a new pump He recommended that I also get the injectors done at the same time which would cost about another $240.

He has no interest in doing the work as he isn't a diesel mechanic and stands to make nothing out of my rig for this work. He is just a bloody good mechanic.

As you could probably guess... I wasn't too happy to hear this news

have you ever used a fuel additive/injector cleaner?

Not going to dis your mechanic, but shop around and talk to alot of diesel shops - some will recommend a complete pump rebuild using totally new parts, some will measure/inspect some parts and reuse them if up to spec, saving considerable costs. I recently had my hilux pump rebuilt, the price difference was $1200 between quotes! I was told that some shops will replace every part inside the pump - which is easy work for the rebuilder to return the pump to factory specs, but is similar to going down to the local parts shop and ordering every panel, bolt, nut, washer, engine/gearbox/drivetrain component, paint, and interior trim part and building the truck at home! Not every component in the pump may need replacing, and some components work out very expensive because they can only be purchased as a kit - you pay whether you need other components in it or not. A pump rebuild will change the vehicle though...the injector nozzles are a 100,000k item anyway.

[JK]

I haven't looked into it much at all. I only spoke with him earlier today.

Thanks for the advice. I will most certainly be looking into it further before I start spending any $$$.

I plan to take it into a couple of diesel places for advice / quotes over the next few weeks.

What additives/cleaners do you recommend?

[Area54]

I don't recommend any of them. The only thing I reckon works best is hygiene and regular inspection and maintenance. Keep everything clean, regularly check the water trap, takes fifteen minutes to check the tank for algae/dirt/water, and install some clear fuel line on the supply line to check for air leaks.

I personally don't like fuel additives (diesel anyway) - many of them can be detrimental to the delivery system. The pump is the heart and soul of the motor - the condition of everything depends on it.

Some additives act as a detergent to suspend the water in fuel and be burnt/passed through the filter/pump/motor as part of the combustion process. As you know the pump uses the fuel as both a lubricant and as a coolant. When the suspended water displaces the lubricant (fuel) in the pump metal contacts metal and accelerated wear occurs. Also they claim to flush out the injectors - GQ injectors crack open at around 1.400-1,600psi - thats a small gerni - you tell me what would remain after that pressure? and the carbon deposits have to be scraped off with a brass brush - how can a mist of fuel remove those kind of deposits? The carbon buildup can be reduced by working the motor properly and not overfueling. Overfueling can dilute the oil, reducing the percentage of oil on the cylinder wall, increasing blowby, puts more soot into the oil, and then problems with sludge form and clog up the rings blah blah blah.

None of this matters if it's a comp rig, but if you have chosen a diesel for it's longevity then this would be of concern to you.

[JK]

I'm hearin' ya. I have always been a little dubious about additives and have never used them.

I'll be checking my gregory's manual for how to check the water trap tonight.

When you say overfuelling, do you mean cranking up the fuel flow from the pump?

[Area54]

When you say overfuelling, do you mean cranking up the fuel flow from the pump?

Yes. Even though it is done with a turbo installation, it still shortens the life of the unit. Everything is a compromise...

[Fisher]

fuel line / pump problems! Buy a 3.0 TDi - I never have this problem

[Area54]

Buy a 3.0 TDi - I never have this problem

You should check the posts regarding this recommendation here ---> http://www.outerlimits4x4.com/PHP_Modul ... php?t=7602

and here ----> http://www.outerlimits4x4.com/PHP_Modul ... php?t=7541

it might make you nervous to think you'll have more problems than just fuel surge...

[JK]

fuel line / pump problems! Buy a 3.0 TDi - I never have this problem

I'll see you in 350,000 ks time...

[bogged]

I'll see you in 350,000 ks time...

LOL a 3.0 last that long?

[Area54]

perhaps there is one too many zeros

[moose]

perhaps there is one too many zeros

or 2 , 2 many !!!!!

[mav]

what about the little filter in the pump inlet banjo bolt

[Area54]

The gauze filter in the banjo bolt on the injector pump was introduced on models after December 1992, but still might be worthwhile checking anyway - might have been changed by a previous owner.

[bogged]

The gauze filter in the banjo bolt on the injector pump was introduced on models after December 1992, but still might be worthwhile checking anyway - might have been changed by a previous owner.

my 91 mod doesnt have it, but a mates late 91 manual does/did....
Talking with dude from BJ Diesel thats doing my pump, he said that these gauze things are making some companies 1000's with false diagnosing of the problems.

He has had a few come in, remove and clean filter, $30 and they drive away. Cheaper

How much was your injectors and pump to get done in the end??

[ozy1]

I just had injectors and pump done for $1388.05

hows that for a well rounded price hey.

goes better now,

[bogged]

I just had injectors and pump done for $1388.05

hows that for a well rounded price hey.

goes better now,

yea mine is gettin done in 2 weekends time $1300 as well, better than the $2000+ was quoted from AG DIesel


goes better, down low? or all round.

did he say how fucked everything was?

[ozy1]

well, it goes better all round, from feb when i got the car, it would idle round 400rpm, now idles just over 600rpm, i used to punch it in second round wet roundabouts and nothing, now, sideways, power increase and im loving it, holds better up hills,

i went and saw the parts when the pump had been dismatled, and he showed me the bits, and told me what was stuffed, why it was stuffed, and my seals were rooted.

the drive shaft on the pump had a wear mark about 1mm deep, which was causing dramas.

[bogged]

well, it goes better all round, from feb when i got the car, it would idle round 400rpm, now idles just over 600rpm, i used to punch it in second round wet roundabouts and nothing, now, sideways, power increase and im loving it, holds better up hills,

There was movement in my pants, for the word had got around, that there really are some neddies in there, that you can actually get to the ground...

There is hope yet then..Thats what Im hoping happens too...

Sweet :arrow: