1hdt (wont go past 140kph)

[lc80]

what would be my remedy for this?? 1hdt engine have been overhauled, injector replaced, injection pump rebuild but still wont go past 140kph, and @120kph the engine sound like its at its max. i dont have the intention of always running at 140kph but i've known people who have driven it at the max of 180kph at the speedo and driven one make @ 160kph with engine not sounding its being maxed out....

any input would be appreciated....TIA!

 

[Graham]

You are in top gear?

Whats the RPM at that speed?

Gra.

 

[lc80]

3k rpm @140kph 5th gear.....do i need to rebuild the transmission?

 

[grantw]

Have you checked the simple things like accelerator cable & how much pressure the turbo is making?

 

[Shayne]

Does it have a home made exhaust maybe its being strangled ?

 

[frank rabbets]

Check the following

1. Air filter. Take it for a run without to try?
2. Pump timing.
3. Does it rev to the red line in neutral?
4. Get someone to floor the throttle (engine off) and make sure it is opening fully. You should not be able to increase the movement in the linkage with your hand.
5. Make sure there are no hot discs after a run meaning the brakes are on.

Frank

 

[lc80]

i have snorkel using k&n air filter. 3" full exhaust already. will try to chech the accelarator cable....tnx for all the input guys...

 

[frank rabbets]

Oh a snorkel, you didn't say you were under water.

Frank

P.S. It could well not draw enough air with a snorkel. Try it with the top off airbox.

 

[Towpack]

If it runs up to the limiter in lower gears (4300 - 4500rpm for the 1HD-T) it's not an airflow issue, more of a power issue which, assuming compression is good, leaves only the fuelling, ie, not enough fuel, inefficient fuel burn due to bad injector(s) or incorrect pump timing.

 

[Shayne]

Maybe some Redex injector cleaner in your fuel will show a difference i read somewhere these injectors are so unlikely to fail they are often ignored even during a main dealer full monty service .

 

[lc80]

ive tried stepping on the gas pedal and using my hand on the cable. it seems that when i step on the gas pedal it doesnt go all the way as opposed to using my hand....should i change or is there an adjustment to it? tnx

 

[lc80]

@shayne : ive already had my injector replaced and all the above mentioned but still sluggish going 120-140kph max...

 

[Shayne]

http://www.ih8mud.com/tech/80throttle.php

But before you do that just check behind the pedal itself for an adjustable screwthread . Maybe it was owned by a shortarse and he /she adjusted the pedal height so they could floor it without getting out of thier seat ?

 

[Roger Fairclough]

What type and size of tyres are you using?

Roger

 

[karl webster]

Fuel pick up in the tank. Maybe blow airlines. Change fuel filter. Make sure pipes from the pump to the injectors are tight if you have had the engine out. Pump timing maybe. I'd get the fuel side checked before anything else personally.

 

[lc80]

tires are mud tires size 285/75/16 stock gearing.....doing 140kph the rpm.are around 3400-3500rpm...would that be normal?

 

[HDJ80]

Sorry to resurrect an old thread of my 1HDT is also having the same problem. I have a manual transmission 1996 hdj80 with the 12valve 1hdt, 285/75/16 stock 4.1 gears.

It also won't go past 130kph and just getting from 120 to 130kph seems to take a long time with the engine feeling maxed out already. At 120 (3k rpm more or less) it's roaring loud already and fuel Eco drops significantly.

Does this mean my engine is in bad shape? Needs a calibration? It's 480,000km already.

 

[clivehorridge]

Mine is the same, nothin past 3,300 rpm in 5th high (130kph) and on dry land!

I don't have a turbo and I have fat 305s, so I've been blaming these things.

I haven't checked my tank filter yet, next job methinks.

 

[Dave2000]

Oh a snorkel, you didn't say you were under water.

Frank

Funny how the silliest things can make you near pee your pants, very funny IMHO!!

For anyone wondering my manual (before I removed the gearbox) would pull 180+ ish km, I say 180+ ish because, the speedometer could be over reading, I cannot remember the revolutions but perhaps 4,300? and the other problem is the speedometer needle was hitting the trip reset button!!!

Done it just for the 'pub chat' but worth noting for future references.

regards

Dave

 

[joinerman]

I thought a 96 should have a 24v in it !!