Aneroid pin 1hdt -simple question (1 Viewer)

[David60series]

Cheers Antony.

1 - I had the pump done because it had done 200k since last rebuild and was starting to smoke as well as in my opinion lug a bit down low.

This had been tweaked on the dyno and was a rocket down low and up high but I didn't know enough at the time to ask the right questions. As such, always just kept it under 500 post turbo EGT.

2 - in reference to the above i had it back to the shop six times in total with various problems after the rebuild I had never experienced. The last time they claimed to rebuild it to the latest specs or 'mod' it. Hence why I'm never going back.

3 - no mods other than beau desert 3 inch exhaust and everything in good order. Uses no oil, oil tests just came back good etc. it can achieve 11.2L/100 on highway if gentle.

4 - want to resolve the low end which is just awful. I can barely take off on a hill with a trailer.

5 - AFRs are around 20-24 from start. No smoke. They him around the 22-23 until 2400rpm or so and start to dip a bit then dive to a low of 18.2 at around 3500rpm foot buried.

6 - EGTs obviously dependent on load, but at 100km/h 350 - 400 on flat post turbo but on a hill will hit 550 and I held it flat with my boat in tow ~1t as a test on a long minor grade and it maxed at 600 which is too high in my books.

As such, unless the aneroid can solve it all the next step will be checking pump on a bench to see what the clowns might have done wrong.

I am at my ends wit.

 

[Antony]

If your going to have a crack at it yourself just follow what I posted above. I can only imagine that if it's been adjusted on a dyno to a point where you were happy with it in the past and now after an overhaul it's not so good it's most likely at spec but getting back to somewhere your happy should be achievable. Did they remove/refit the pump too? I would hope it's timing has been set with a dial gauge. As for egt's 650 max post turbo but I'd be more comfortable 550-600 max. Shame your in Oz otherwise you could have sent it to me We're the biggiest fuel shop in NZ based in Oamaru (of all places).

 

[David60series]

Cheers. It has been such a disappointment that I would send it to you in NZ rather than go anywhere near that place again. Better still bring it over and catch a Highlanders game too.

as for the timing I am worried about that too. It was retarded too much on one of the six occasions, grey-white smoke and gutless. Pump also leaked afterwards.

I asked that it be set properly the last time. I really should find another shop and get the timing checked.

I will give it a crack. So I shouldn't be worried about pulling the aneroid pin out and not getting it back in? It would be great to see where it has been riding.


I come from a petrol/carb/ignition background so I'm only learning this stuff on the trot.

 

[Antony]

Sounds like a plan. I'm a crusader by birth but adopted the highlanders when I moved south a few years ok. It's a shame and not right that your having these troubles after a paid job. I'll post some pictures with a few more details after work which should be of some help.

 

[Imwhere]

That sucks you've been stuffed around by a shop. very frustrating.
If you want it done right do it yourself hey! Haha!
Good luck with it and im sure you will get a better understanding of what does what when you start playing with it.
Let us know how you go mate.

 

[Antony]

So pulled apart a boost compensator at work today. This ones off a marine spec 1HD-T. This is looking down inside where the aneriod pin locates. The follower pin has moved forward because its under spring tension.

Too move it back you would need to remove this plug which sits in behind the throttle shaft, to gain access to the spring. That's if the last person that overhauled your pump refitted it. It inst necessary too, I do because put it there for a reason by Denso but Bosch and Zexel don't use a spring here.

So if you were to remove the aneriod pin you need to remove this plug so you can push the follower pin forward so you can refit the aneriod pin. If you were to remove it this is what you would see.

Thats the eccentric pin. You can imagine when this pin travels downwards and its total stroke stays the same you can change the rate at which fuel increases. Also the position on unboost/boosted in relation to follower pin changes when rotating the shaft. Shims at the base (under my thumb) allows for the total stroke to be changed, so you can either run it just on the slope or a combination of slope and flat. This allows you to change the total gap in fuel quantity from boosted/unboosted.

 

[Antony]

This is the cam that adjusts unboosted. Obviously out and upside down But the thickest area when directly above the aneriod pin gives the most amount of unboosted fuel.

Star wheel adjustment through here. Less tension = faster rate of fuel increase for given boost.

And when I say about feeling the tension of the spring you can see in this image how the spring is holding up the cover. And this will change depending on where the unboosted cam is too. Thats a good way to feel when the cam is at max fuel as it has the most tension on it.

But in the mean time I would be marking you diaphragm as below.

Work in 1/4 turns and fine tune with 1/8 turns. I looked at a few stock 1HD-T aneriod pins today and they dont have the range of travel of the marine spec one. Aim to find the spot where you have the best punch off the line but keep you egt's in check. Now it might be that the best spot starts off the worst power wise and your egt's up top drop but adjusting your full load screw can bring it all back. The aneriod pin is designed to give you multiple different fuel maps but is ment to be adjusted in conjunction with the full load screw.

 

[IanB]

@Antony Great pics and info, thanks for sharing!

 

[David60series]

Awesome! Thanks for taking the time to do this. Really appreciate it!

I had previously thought that the maximum fuel ramp on the eccentric pin was the best place to start, but I can see now that that's not necessarily so.

I can also see its important to get the pin moving early too. I suspect mine is barely moving before ~3psi.

The shop set the eccentric pin and cam plate almost at maximum, so it might turn out that it is easier to tune with a touch more main screw. I've got nowhere to move an adding fuel at no-boost at present where it feels and reads like it needs more, but also got high EGTs up high and a little bit of smoke.

 

[Imwhere]

Nice info and great pics Anthony!

Do the aneroid travel limiter spacers (or whatever there called) usually come in a standard pump? Mine has none is all and my pin has an overboost protection ramp which that one doesnt. What number pin it that?

The long ramp on the aneroid will also be why your turbo is slow to spool as its the longest ramp and slowest to deliver the extra fuel.

 

[David60series]

Good question on the spacers - i am also keen to know. I found a denso listing for these but there were only two sizes available from memory.

Cheers on the ramp info. Another wrong assumption I had made as most online info points only towards using 'maximum'.

 

[Antony]

The spacers/shims aren't always fitted and most likely arent if you have the overboost protection. A shim can stop it hitting that part though. Don't know about sizes but can check. I dont have the part number of the pin above. This the pin number from the high HP Yanmar pump 096465-0790.

 

[dmac25]

The spacers/shims aren't always fitted and most likely arent if you have the overboost protection. A shim can stop it hitting that part though. Don't know about sizes but can check. I dont have the part number of the pin above. This the pin number from the high HP Yanmar pump 096465-0790.

hey mate do you know of anywhere to order such pin or anyone else know where to order one of these Yanmar fuel pins