The Official 1HD-T/FT Fuel Pump Mod Tuning Thread

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vwluv10338 said:
I had been trying to get a video uploaded but I'm on vacation and don't have wifi. Hopefully this works

ETA: I'm getting a little off topic but I guess the lesson here is you can't tune around broken parts be it a worn pump, leaky injectors, or a blown turbo


Here is my turbo. Click the link

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Ahhh dude, that sucks.
I hope you get a fast and satisfactory resolution from the supplier.
Keep us updated, I think lots of people will be interested to see how things pan out for you

I'd seriously consider bypassing the turbo to get home, having had a turbo go pop, I'd be really hesitant to keep driving it at all in that state.
 
Don't be discouraged mate there's always teething issues with anything custom. As long as you receive GOOD! service and support .

It's a c$&t when things fail far from home though. I carried a spare for a year, the moment I took it out bang snapped shaft . That was the 3rd turbo from a big company. 2 turbos did under 5000km the 3rd did 20000. Changed turbo supplier, sent me a trial turbo still going strong 60000km later .
 
I have done a bit of tuning on my 1hdt and down a dyno run before the pump is sent away for a rebuild. Turns out the pump acts like it's warn or internal timing is shot. Boost comes on strong but still smoky at 24.1

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Good info @Nathjf88
With your pump like that, did that also result in hight EGTs?
How many k's on your pump and injectors?
I Think I'm in the same position and contemplating a rebuild also.

Can I confirm that I'm reading your dyno right and that you are running 22psi and 25:1 AFR at 2500rpm.
 
Yer I had high egts and high cruise boost. My wastegate is set to 25psi my gauge showed 28 but the dyno showed 23psi. I don't know how many kms my pump had done but it also had issues with the idle hunting and would stall on hills when out wheeling.

His dyno showed 23psi and 24.1 pump was still smokey
 
Right. Thanks.
I'm running high EGT and a bit smokey while lean at high boost.
It doesn't feel as torquey as it should either I don't think.
It also plays the stall out game when on steep inclines while wheeling too.
I'm still measuring things but I think I'm going to be up for a pump rebuild soon.
Let us know how your new pump performs.
 
diby 2000 said:
Right. Thanks.
I'm running high EGT and a bit smokey while lean at high boost.
It doesn't feel as torquey as it should either I don't think.
It also plays the stall out game when on steep inclines while wheeling too.
I'm still measuring things but I think I'm going to be up for a pump rebuild soon.
Let us know how your new pump performs.
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Will do. I'm getting ads to build the pump
 
OK, I finally got around to digging into my pump to muck with things...off to a great start. The aneroid/diaphragm assembly won't clear the intake manifold to remove from the pump, it jams against the runner and I don't want to force it as the side load could damage something, from watching videos it should just slide straight up and out, any ideas?

From there, I tried to push the pin back down and into the pump, and it won't go. I've had this pump tuned previously, and assumed the pin would have been ground for reinsertion, doesn't appear to be the case. I can't get the pin out to grind it myself either. Took a quick vid to show what I'm dealing with, any ideas?

Having just had the intake manifold off a few weeks ago, I'm not real jazzed about the prospect of doing that whole job over again right away.

Is the pump timing a possible suspect? I had is set when the "power rod mod" tune was done about a year ago, along with a valve adjustment, and it's been running great since.

Edit: I marked the pin relative to the diaphragm, and removed the top nut from the assembly, I was able to get the diaphragm and pin out separately, a bit of a PITA, but a workable solution. I was also able to confirm the pin was ground, and I just wasn't pushing down hard enough to overcome the follower pin.

 
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@IanB I have not played with a 1HD-T pump yet. But this is the first time I have heard of this happening to this setup. I am in a similar position now that I have advanced the timing with my 1HD-FT though.
I had to disassemble the diaphragm as you did to get it out, then I have ground a clearance notch in the top diaphragm washer to clear the runner. I didn't take a picture sorry. I'll grab one when I can.
I have also previously clearanced a mounting casting on the manifold to enable removal of the pin before I advanced the timing.
Advanced timing would be the main culprit I would think. Do you a know what your timing is set at?

@vwluv10338 I have not ground my aneroid yet. I'm still running my rough tune with the stock profile. I'm still waiting for my replacement turbo and I have been too busy to spend any time on my cruiser lately anyway. I hope this all chances in the next month.
 
I imagine my pump is timed on the advanced side of the spectrum, but I don't have the spec, and I've never looked at the timing marks to know.

Clearancing the washers is a great idea, I'm going to look into that! I've gotten pretty good at separating and reuniting the aneroid and diaphragm in the correct orientation at this point, but that's a simple fix that makes it avoidable.
 
Is it contacting the intake runner? Or like on my 1HZ, there's an unused threaded boss on the underunside side of the runner that could be ground away for clearance.

I found with my 1HD-T, the difference in alignment of match marks from retarded to advanced was minimal. only 1, maybe 2mm of pump rotation, and the chunky OEM marks still more or less looked aligned.
I scribed a line on mine to see better how much change there was as I did the timing.
 
I was careful to only remove the material required to make this work. I only had to notch the top washer at this stage to allow removal and installation. I also made special effort to ensure where I had removed material that what was left was very smooth as to reduce possible diaphragm damage and fatigue points.
 
mudgudgeon said:
Is it contacting the intake runner? Or like on my 1HZ, there's an unused threaded boss on the underunside side of the runner that could be ground away for clearance.
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It is the runner it's hitting, it doesn't feel like it has a lot further to go to clear the pump either.
 
So I started a thread on a FB 1Hdt group asking for pics of people's modified or purchased fuel pins. In case you missed it someone posted this.
"
The caps are 125 nzd and the pins are 300 for a tuners kit of 5 there is no gst on export though so will be 15 % less than that and also aud is stronger than ours"

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