1991 1hdt (2 Viewers)

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Oct 16, 2016
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Guys I am having and annoying problem

The engine shakes alot in drive or reverse at a stop when warmed up.
I have changed all external seals on the pump, pumped primer pump whilst engine was shaking. If I drive off, engine shake goes away. If I hold 900 rpm with ac on, it settles down a bit. It idles at 800 and when engine is shaking, rpm stays the same. Engine mounts are good.

HELP

HELP


Engine mounts are good
 
Interesting. Why are you thinking that? Also how do I test that?

well because I thought something similar, mount, timing, something just felt out of sync. Then one day when it was having one of its episodes I put it in neutral and it went away instantly.
 
It idles at 800 and when engine is shaking, rpm stays the same.
How many kms on it? Auto (800 RPM) or Manual (650 RPM)? Idle up to 950 with A/C on? RPM in D with brake depressed?

I have changed all external seals on the pump, pumped primer pump whilst engine was shaking.
Firstly, when was the last time your injection pump was serviced? (likely) Could be a restriction or air getting in as well.

A stall-test would help rule out the tranny (unlikely)
 

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The stall test was accurate. No issues

Idle park ac off 850
Drive ac off at stop 800 engine beats up. Rev to 850 no beat up

Park ac on just under 900
Drive ac on a tad bit above 800if I rev to 900 beat up goes away..
 
Its sounds like uneven fuel delivery with one or more injectors not getting a full charge at low rpm.

What happens when its cold? Does it run smooth, is there any smoke , what colour etc.

Check all the cheap things first

How about a video?
 
Its sounds like uneven fuel delivery with one or more injectors not getting a full charge at low rpm.

What happens when its cold? Does it run smooth, is there any smoke , what colour etc.

Check all the cheap things first

How about a video?
On cold it works fine till it get warm so about 5 mins of driving and it starts. It starts on half a tumble all day every day. Slight puff of black smoke for about a second.
It only happens in a gear...is there load compensator thing to adjust? It mostly happens with ac on thou. No ac and it rarely acts up

How to check injectors?
 
It only happens in a gear...is there load compensator thing to adjust? It mostly happens with ac on thou. No ac and it rarely acts up

How to check injectors?

There is a fast idle that is activated by vacuum that comes on when you turn the a/c on.

If its a fuel injection problem, I think it will be in the pump. You cant check injectors without the correct gear and 1HD T are 2 stage, meaning they have 2 charges of diesel each time it fires. So they really need to be tested by a pro who has the facilities to do it.
 
The fast idle thingy works. It pulls in on ac turn on and idles up the engine. Is it adjustable? Maybe I can raise the idle up a tad?
 
I think it has 3 idle speeds, it did on the older models. There was a notched section with 3 notches. You connect it to the one that gives you the ideal speed you desire. I always had them on low so the idle only jumped up 50rpm
But if its connected and working , I doubt that's the problem.

And the fact it only does it when warmed up is another complication.

Is your pump leaking any fuel?
 
Came by diesel pump specialists shop to have a professional opinion. They have advised that injectors valves ect are all fine. They are removing the pump as it is not "seeing load".
They are going to bench test it and open and repair as needed. Will collect back today and advise the outcome.
 
ok got a call from shop. pump body is worn. therefore losing pressure. they have increased the pressure in pump to compensate and advised i source another housing, either used or refurbished already.

Lets hope it temp fixes my problem until i source one. anyone has a spare 1hdt pump by chance?
 
The pump body is used in many Toyota applications.
Internals have some variations depending on engine.
Your injectors are two stage .
Also used in Yanmar marine and industrial equipment.
 
So pump repair didn't fix the problem. Going back mon to have injectors serviced. They suggested maybe the idle stage springs may have broken ect in more than one injector. As they cracked all 6 injector lines when the engine was rough idling and only the 1st 3 injectors has a significant change in idle. The last 3 had minimal to slight change.
 
ok got a call from shop. pump body is worn. therefore losing pressure. they have increased the pressure in pump to compensate and advised i source another housing, either used or refurbished already.

Lets hope it temp fixes my problem until i source one. anyone has a spare 1hdt pump by chance?


I dont think you can service the housing. Its most likely flogged out around the timer piston. I got a new one for a 1HZ $500AUD a few years back.
Finding good low klm pumps is not easy. No one removes a good pump from a good engine.
 
Anyone has a spare 1hdt pump by chance?

I had to replace the housing as well. Most pump specific parts are near impossible to find using Toyota part #'s - need to search for the Denso part #.

The housing, which is Toyota Part #22101-54260, is Denso Part #096110-0292 (printed on pump ID tag). Paid $250 CAD for mine which I thought was reasonable. Any Denso dealer should be able to order you one.
 
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