1HD-T over reving on start up

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chrisspaulding

chrisspaulding

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Hello all,
I'm installing a 1hdt/a442 combo into my Portugese spec bj73. I went to fire it up for the first time today and the engine catches and the revs spin up and out of control. I have not converted the tach, so I don't know the exact rpm, but this thing spins up and keeps going. I am able to kill the engine by turning off the ignition.
The engine is out of a 1993 JDM hdj80. It was running in the truck before removed. I have done no modifications other than connecting it up to the various bj73 systems.
I initially thought the cylinders may have gotten some oil in them as the engine titled on its side during shipping. The truck will fire and rev up and blow a ton of black smoke, like it's over fueled.
I've worked on a number of B and H series motors. This is my first 1hdt. I'm at a loss. I've started and stopped it 5 times. I'm afaid to do it anymore out of fear of blowing the motor.
I checked the throttle and throttle cable. They are ok. I'm not sure about any cold start systems or auxiliary fuel systems. Any direction and advice would be greatly appreciated.
Thanks,
Chris
 
You say throttle is fine-does it do the same with both rods (primary throttle and A/C) disconnected from the injection pump?

If it stops when you turn the key, it is not running on it's own oil.
It seems to have the cold start system-I do not know about that and if it could get stuck and cause the symptoms you are describing.

How about the rev up for the automatic, does it do the same when that is disconnected?
Jan
 
Jan-78FJ40 said:
You say throttle is fine-does it do the same with both rods (primary throttle and A/C) disconnected from the injection pump?

If it stops when you turn the key, it is not running on it's own oil.
It seems to have the cold start system-I do not know about that and if it could get stuck and cause the symptoms you are describing.

How about the rev up for the automatic, does it do the same when that is disconnected?
Jan
Click to expand...
I don't know what the rev up for the automatic is...
 
Did you replace the timing belt? Is the timing right? I would disconnect the throttle cable/s from the pump and then see what happens, the rods can be set wrong i.e. full throttle, or idle.

regards

Dave
 
Jan-78FJ40 said:
You say throttle is fine-does it do the same with both rods (primary throttle and A/C) disconnected from the injection pump?

If it stops when you turn the key, it is not running on it's own oil.
It seems to have the cold start system-I do not know about that and if it could get stuck and cause the symptoms you are describing.

How about the rev up for the automatic, does it do the same when that is disconnected?
Jan
Click to expand...
It revs up with both rods disconnected.
 
Dave 2000 said:
Did you replace the timing belt? Is the timing right? I would disconnect the throttle cable/s from the pump and then see what happens, the rods can be set wrong i.e. full throttle, or idle.

regards

Dave
Click to expand...
Dave,
I did not replave the timing belt. I did nothing to alter the timing. It was running fine before it was removed from the hdj80.
It over revs with all linkages disconnected.
 
I would disconnect the fuel stop, and then try to start it and see what happens. What is the sump oil level like, do you have a lift pump in the tank? Would not normally cause this but just throwing out ideas before turinging in.

regards

Dave
 
Dave 2000 said:
I would disconnect the fuel stop, and then try to start it and see what happens. What is the sump oil level like, do you have a lift pump in the tank? Would not normally cause this but just throwing out ideas before turinging in.

regards

Dave
Click to expand...
No lift pump in tank. Oil is at the high mark. Throttle resting on throttle stop.
 
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That's the famed ACSD (1HDT ACSD replacement).
I don't know if that can cause the symptoms (don't have it).

Ad above: I thought the automatic was connected to the injection pump as well, but I am not sure (have a manual).

Does the truck have cruise control?
 
Jan-78FJ40 said:
That's the famed ACSD (1HDT ACSD replacement).
I don't know if that can cause the symptoms (don't have it).

Ad above: I thought the automatic was connected to the injection pump as well, but I am not sure (have a manual).

Does the truck have cruise control?
Click to expand...
The TPS is connected to the transmission computer. There's a lockdown cable connected to the transmission, but that's it. No cruise control.
 
chrisspaulding said:
The TPS is connected to the transmission computer. There's a lockdown cable connected to the transmission, but that's it. No cruise control.
Click to expand...

Thank you.

Just stating the obvious:
-it's not running on it's own oil
-it has not been manipulated and the pump has not been off
-it ran fine before
-timing has not been changed
All correct?

Someone that knows the ACSD please chime in. Can that break and cause this condition? It is there to overfuel when the engine is cold, so it sounds plausible.
It can be eliminated easily and block off plates are available for a few $. Maybe that is worth doing next.

Otherwise I think you need the pump off and have it looked at by a good injection shop. Seems to me that the pump is the only possible culprit.
Jan
 
back the idle screw out so the arm returns back to firewall as far as it can.

See if lead shield is off the fuel screw.

if those are adjusted, some one has mucked with pump.

remove the cold start (blocking plates are $5 at diesel shop or free plus an o ring). You can run one of the rubber hoses as a bypass- don't need to buy anything.
 
Jan-78FJ40 said:
Someone that knows the ACSD please chime in. Can that break and cause this condition? It is there to overfuel when the engine is cold, so it sounds plausible.
It can be eliminated easily and block off plates are available for a few $. Maybe that is worth doing next.
Click to expand...

I believe the ACSD just advances the timing, doesn't add any extra fuel. FWIW.
 
I thought it pulled on the throttle cable or the sort to idle the truck up when it was cold? or maybe I'm out to lunch.
 
That pic of the ACSD is showing full cold start IIRC? Memory is a bit foggy as I took mine off way back.

When activated is uses to alter the timing and put the throttle forward, I wondered if somthing got bent when the motor fell over? Anyway, you can remove the linkage to it for the time being just to rule it out. I am laid up with a busted ankle at the momento and my car is miles away so cannot get you a picture of the lnkages ect.

The ACSD can be removed with no ill effect on the engine in cold climates, really cold may be an issue though. Unless you have the blanking plate just remove the linkages from it.

regards

Dave
 
Has the full load adjusting screw been tampered with? Wire missing? Does the throttle lever on the pump feel normal when you move it back and forward by hand with the engine off?

These engines sound loud at 2000-3000rpm. When I did an oil pressure test and was required to run the engine for a minute at 2500(I think) it sounded like all hell breaking loose.
It may not be revving as high as you think.
 
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I'd agree with Rosco about the noise.
Revving one up in a shed is noisy. Revving it to red line or so the pump is on the governor is noisy as fxxx!

I had a pump failure in my hdj81 which saw the engine run away, rpm took the taco way above red line. I expected to see pistons exploding through the hood. It was scary loud
 
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