12HT feul pump proper calibration setting required

Submitted: Saturday, Aug 24, 2013 at 16:57
ThreadID: 104027 Views:9495 Replies:2 FollowUps:6
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I have Toyota landcruiser HJ60 1986 and have replaced its 2H engine with 12HT engine and I recently somewhat fixed its sensitive throttle Kangaroo hops on low RPM caused due to incorrect setting of its fuel pump

I still thing think its pump rack is not correctly setup on the delivery elements as during idle the engine seems to slightly accelerate up and down.... and when I put accelerator on throttle there is a big jerk feel.

Is there any Toyota standards for its proper calibration? as most of these pump shops have their own standards and their results seem to vary from shop to shop. I read somewhere pump has coarse and fine idle speed set screws which are in the governor housing and they need to be set up as per Toyota specs. Would it help if I change of internal servicing parts and replace these with original Toyota servicing parts inside the pump.
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Reply By: Rockape - Saturday, Aug 24, 2013 at 18:19

Saturday, Aug 24, 2013 at 18:19
Gregory's landcruiser HJ series diesel 1980 to 1990. Gregory's #502

This will give you the injection timing for the 12 ht and trouble shooting
AnswerID: 517035

Reply By: Tim HJ61 (WA) - Saturday, Aug 24, 2013 at 21:22

Saturday, Aug 24, 2013 at 21:22
The proper calibration settings are available in the factory service manual. If you have mislaid the link to the FSM I have given you several times before, let me know and I will give it to you again. The parts rarely wear out, but they do need to be adjusted correctly

If the big jerk at the start off also produces black smoke then your OFF BOOST fuel screw needs to wouNd OUT a quarter turn.

AnswerID: 517040

Follow Up By: Tim HJ61 (WA) - Saturday, Aug 24, 2013 at 21:34

Saturday, Aug 24, 2013 at 21:34
The other thing that causes lumpy idle is too low idle speed setting. Increase it to 750rpm and see what happens

These engines are always very touchy low down. Unless its undrivable, just get used to it
FollowupID: 796565

Follow Up By: Naveed Merchant - Sunday, Aug 25, 2013 at 11:30

Sunday, Aug 25, 2013 at 11:30
I need calibration setting . I was able to to locate engine manual of 12HT from http://www.peoplehelp.com.au/landcruiser/manuals/Engine_manual_2H_12HT.pdf but couldnt understand where to look for it

Whats FSM?
FollowupID: 796592

Follow Up By: Tim HJ61 (WA) - Sunday, Aug 25, 2013 at 12:05

Sunday, Aug 25, 2013 at 12:05

I always try to be helpful to you. So that is why I wrote
"The proper calibration settings are available in the factory service manual. If you have mislaid the link to the FSM..." in my first reply to you.

I wrote out Factory Service Manual, I accept I did not put these in Capital Letters, then I wrote FSM. FSM = Factory Service Manual.

Yes, you have downloaded the correct manual from my site. I spent considerable time taking the manual I found elsewhere on the internet and running it through Adobe software so that search functions work on this document. A search using your PDF (Portable Document Format) reader would have found reference to the Fuel System. In fact, if you go to the document index and click on the heading Fuel System, it will take you right there. From there you will see the Fuel System index and locate the instruction to do with the Injection Pump. They are on page FU29

Naveed, this is the Factory Service Manual. It contains all the information a competent repair shop needs to get your pump running correctly.

I SERIOUSLY AND SIGNIFICANTLY URGE YOU to NOT let anyone tinker with the insides of your injection pump. These pumps are renowned to last a very very very long time without tinkering inside them. There are four adjustments on the outside that you can play with if you are really confident and can return the settings to standard should you wish.

The first, and I suspect what your problem is, is the idle speed adjustment. This is a simple adjustment near where the accelerator cable joins the injection pump. I think your lumpy idle is from the idle speed being too low.

If you increase your idle speed to over the factory standard setting and you still have a very lumpy idle, then someone has stuffed up your governor settings. A competent injection pump shop with a proper test equipment will be able to reset the pump when it is OFF the vehicle. If there is no competent injection shop in your region, you will need to find someone in your own country or post it to a place in Australia for recalibrating.

There is also an adjustment in the same area that controls the idle speed when your air conditioner is turned on, or when the vehicle is cold. Simple adjustments.

The other two adjustments are your maximum fuel setting, and your off boost fuel setting which controls the fuel as you initially accelerate. I am not going to go into this here, but have covered it at www.peoplehelp.com.au/landcruiser.

Most of the time NONE of these things need touching. If you have tinkered, well.... it's going to be hard to help you.

I've also suggested that the level of technical expertise in this forum is sadly pretty limited and you are better off at I8HMUD.com or http://www.outerlimits4x4.com forums for tech support.

I trust this is useful feedback.

FollowupID: 796596

Follow Up By: Naveed Merchant - Tuesday, Aug 27, 2013 at 11:24

Tuesday, Aug 27, 2013 at 11:24

Many thanks for detailed advice.

I will ask the pump shop to use manual for setting the four adjustments on the outside of the pump.

Would you please let me know what is the factory setting for idle speed adjustment with and without AC for 12HT.

FollowupID: 796710

Follow Up By: Naveed Merchant - Tuesday, Aug 27, 2013 at 13:49

Tuesday, Aug 27, 2013 at 13:49

Just realized the pump shop guy cant read english and I will arrange its translation for him and wanted to know which page provides the setting of the four adjustments outside the pump.

Many thanks in advance
FollowupID: 796719

Follow Up By: Tim HJ61 (WA) - Tuesday, Aug 27, 2013 at 15:26

Tuesday, Aug 27, 2013 at 15:26
As per my previous reply it starts at FU29

Any mechanic should be able to find and adjust the idle speed adjustment at the end of the accelerator cable. The air cond idle up adjustment is there too. Correct idle is 750rpm I believe.

The on and off boost fuel adjustments are not needed unless there is black smoke under power, or when first accelerating. There is always a puff of smoke at engine start up.

FollowupID: 796725

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