1990 Toyota pickup from AAZ to AHU MTDI

samuraitd

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ahu mtdi samurai swap, 1991 jetta ecodiesel
Filter does have the plastic tee. Its located on the turbo side sheltered behind the intake setup so I dont think thats the case. I have not seen any local supplier for clear lines in the diameter I need. Any recommendations online?
The thermostatic t can crack and leak air. That's why you need a clear hose going to the pump. I would just look on ebay to find some tubing here:
http://www.ebay.com/bhp/5-16-clear-fuel-line
 

vanbcguy

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'93 Passat - AHU mTDI with GTB1756VK
Most OEM setups have clear supply and return lines. If you ever have issues with air in your system it is hugely helpful to know if it is happening before your pump or in your pump.

Sounds like your filter should be good and warm. The problem is either air getting in to the lines or fuel not getting out of the tank for some reason. What kind of pickup do you have in the tank? There isn't still a gas fuel pump in there, is there?
 

djtc

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ottaws
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mk4 golf tdi
Checked my 02 golf and it only has a clear supply.

As for whats in the tank i have no clue since i bought the truck with an aaz in it then i swapped the ahu. The po sAid that the toyota pump was left in there but i dont hear it when the ignition turns on. He also left the stock fuel filter. Im going to drop the tank to investigate and re do the lines as well.

Any suggestions for what to do in regards to the fuel tank set up ?pump or pumpless?
 

vanbcguy

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Most stock gas pumps won't last all that long with diesel. If you choose to run a lift pump it needs to be diesel rated.

I would ditch the stock Toyota pump if possible, though really checking out whether you have any obstructions in the lines would be the first step.

If you are going to do any real off roading then a decent lift pump that doesn't block flow would be ideal. I'm using a Facet Posi-Flow on mine, rated for about 6 PSI. You can pull fuel through it when it isn't running so if it fails it won't leave you stranded. The VE pumps have a pretty good lift pump in them already but if you're on any extreme angles or anything an extra pump would help.
 

jimbote

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spiral arm, milky way (aka central NC)
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Most stock gas pumps won't last all that long with diesel. If you choose to run a lift pump it needs to be diesel rated.
I would ditch the stock Toyota pump if possible, though really checking out whether you have any obstructions in the lines would be the first step.
If you are going to do any real off roading then a decent lift pump that doesn't block flow would be ideal. I'm using a Facet Posi-Flow on mine, rated for about 6 PSI. You can pull fuel through it when it isn't running so if it fails it won't leave you stranded. The VE pumps have a pretty good lift pump in them already but if you're on any extreme angles or anything an extra pump would help.
a toyota gasoline intank pump will hold up fine to diesel ... i ran mine over 40k miles on diesel and that was on top of the 190k it had pumping petrol ... when i swapped it for a low pressure unit it was still working great ... i really don't think the build materials between intank gas and diesel pumps are that different ... no rubber parts to speak of that can degrade in diesel
 
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vanbcguy

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'93 Passat - AHU mTDI with GTB1756VK
Well the stock VW pumps certainly don't last long, I don't have extensive experience with Toyota myself.
 

djtc

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mk4 golf tdi
Is your posi flow an external pump ? If so what did you do with the old in tank pump assembly/sock?
 
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vanbcguy

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'93 Passat - AHU mTDI with GTB1756VK
Yep, external pump. I have it mounted post-filter as Racor recommend.

My vehicle was a diesel originally so there isn't an in-tank pump. It does have the sock, nothing wrong with that though.

If there is ANY chance that you've had water in your fuel tank you could have some algae buildup too, especially if you got contaminated fuel at some point (like from a jerry can or something - it's the diesel equivalent of an STD). Check for black guck in your tank, it tends to get pulled in to the sock, coating it and starving the engine.
 

djtc

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mk4 golf tdi
I'll check all of that , and i'll report when I get back.

to do:
-Remove bed
-Inspect fuel pump assembly
-Install low pressure external pump
-Remove Toyota fuel filter ( run vw filter independently)
-Replace fuel lines
-Replace fuel filter

Hopefully that will do it.

Is this the pump you used?
http://www.ebay.ca/itm/1x-Facet-601...arts_Vehicles_CarParts_SM&hash=item35df143e10

Also they recommend to install post filter but closest to the tank aswell... should I run a secondary inline filter ? Tank->inline filter->Posi flow ->vw filter-> IP
 
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vanbcguy

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'93 Passat - AHU mTDI with GTB1756VK
I can't remember the exact part number I used unfortunately. Just make sure it will flow fuel when off though and you should be good. Oh and don't go too high on the pressure or you'll blow the front seal out of your injection pump.

The reason for having the pump post filter is that the pump will churn up any water in the fuel making it harder for the water separator in the filter to do its job. When the fuel is under vacuum it is easier to break out the water. Lots of people ignore this, in fact really if you look at the PD and later VW engines they all have an in - tank pump before the filter so it may not be the end of the world, especially if the line from the pump to the filter is reasonably long. That said there's nothing wrong with more filtration. The stock VW filter is very corse, like 25+ micron. I am running a 2 micron Racor on mine without the stock filter at all.
 

djtc

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mk4 golf tdi
HELP!

Alright, since my last post I removed and re installed the motor and tranny to replace a clutch throwout bearing. I installed a new fuel filter, she starts up on the first crank even on cold days without gp's. However , after my first drive about 5-7min in to the drive the symptoms re appeared (loss of power and stalling).

So I bought the 911 diesel supplement to de-ice fuel and poured it in to my tank to rule out an iced fuel/ or pump pickup. Went out for a drive and the same symptoms happened about the same time 5-10min into the drive.Now ,sometimes if I let the motor bog down it will run like crap for a minute then revive itself with a few blips of the trottle. A few other things I noticed is that when the symptoms are occuring ,the motor will stay alive if I keep the revs up really high. Secondly, my truck use to boost easily to 20-25psi and now it struggles to reach 5-8psi.

Today I went to get some clear fuel line to see if there was air in the system. After the hose install , you can see in the first and second video that there is plenty of air in the lines ( more on the supply side than the return) . I tried pressing and jiggling the fuel filter T and there was no change. Could being low on fuel (1 bar over Empty ) affect this somehow? Its been pretty cold here (-15c to -30) lately i'm sure thats not helping.

Video1 (click)

Video 2 (click)
 

samuraitd

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ahu mtdi samurai swap, 1991 jetta ecodiesel
To me that doesn't look like that much air, I easily have that if not more on my jetta.
 

djtc

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ottaws
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mk4 golf tdi
What would i be looking for with the gauge?


I guess im just going to put in new hose and the bosch lift pump you re running jimbote to rule out any in tank problems.
 

vanbcguy

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'93 Passat - AHU mTDI with GTB1756VK
If you see a lot of vacuum that will tell you that something is plugged up.

You've either got a blockage or a leak on the suction line most likely.
 

djtc

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mk4 golf tdi
What makes me wonder is why does it usually happens after 5-10min of driving for a short period of time (5min avg). If there would be blockage or a leak wouldnt it be consistent ? The truck always starts up just fine.
 

vanbcguy

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'93 Passat - AHU mTDI with GTB1756VK
If it is partially blocked it will start OK, but as it runs (especially when the revs increase and the pump tries to pull more fuel) it will start building a vacuum. It'll still be able to pull fuel from the filter but eventually enough of a vacuum will build up that it won't be able to run. When you switch it off that vacuum is still present and it will continue trying to suck fuel through till everything equalizes.
 

samuraitd

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ahu mtdi samurai swap, 1991 jetta ecodiesel
A very simple way to test would be to just run a small fuel jug in the engine bay with the lines going directly into that, eliminating the rest of the fuel plumbing. My other thoughts for a restriction would be the pick up in the tank.
 

djtc

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mk4 golf tdi
Eliminating the rest of the fuel system with the jug would be and idea .but i would feel a little uneasy driving around for 10-15min with a jug in my engine bay to see if the symptoms are still persistent.
 

jimbote

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spiral arm, milky way (aka central NC)
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Eliminating the rest of the fuel system with the jug would be and idea .but i would feel a little uneasy driving around for 10-15min with a jug in my engine bay to see if the symptoms are still persistent.
just secure the jug with a bungee and keep it away from the exhaust ...it's not like gasoline, diesel is very difficult to ignite without an open flame...
 

samuraitd

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ahu mtdi samurai swap, 1991 jetta ecodiesel
Just don't take any sharp corners, sudden starts or stops, and strap it in with a bungee like Jimbote said, and you should be good. IMO that will be the quickest, easiest way to tell if you have a problem with the fuel plumbing.
 
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