Potential HJ61 5spd touchy throttle fix

[dieselDaryl]

I finally had it this weekend with this "lurching" throttle problem in my 5 speed HJ61. I felt like I was back in driver's training giving myself whiplash and spinning the tires every time I went over a big bump or log. I have tolerated this for FAR TOO LONG. The kicker was on a couple of steep rock ledges where I was letting off the throttle and spinning the tires at all of the wrong times. I would sum up my low speed driving that day as the complete opposite of finesse.

Anyway I remember seeing a post on W-Js site about an extra throttle spring that wasn't installed on some HJ61s. I looked on the injector pump and low and behold, there was a spot for an extra spring. So I went to Princess Auto in search of a suitable srping and bought a couple. The one I settled on is listed as:

11x70MM spring (Princess Auto part # 3806262).

I had to remove about 5mm of the coils as it was a touch too long. But it was stiffer than the shorter ones they carried so it was the only option in my mind. Anyway, its a really easy install (we're talking 5 seconds aside from modifying the actual spring). You will see two pins on the injector pump about 50mm from each other and it goes there.

I just got back from a test run on a couple dirt trails and it has made a SIGNIFICANT difference. Its not 100% perfect but MUCH more driveable offroad. I even noticed a difference on the pavement.

I plan to head out next weekend to do a bit more testing, especially in a steep bumpy low speed crawl. I will report my findings..

Bonus: Maybe it will save those with a heavy fot a bit of mileage too

Daryl

 

[Stone]

Interesting...I've also heard about this spring mod on this board a while ago, Daryl. If you have a digital camera, it would be great if you could snap a quick pic and post it up. Cheers.

 

[Greg_B]

Daryl! Welcome to BC. I trust the move went well?


I recall that post of WJM and I believe there was also mention of moving the pivot point for the pedal up a bit, as well as the possibility of a shock absorber behind the pedal ala some high end European vehicles.

As Stone says...

gb

 

[Tapage]

pics please .. sound good .. !

 

[dieselDaryl]

GB:Yup, all moved out here and already been out in the hills the past two weekends...

Yes, I will definately post pics and a little better report of the difference once I have done some more testing. One thing I've noticed is the hand throttle is MUCH harder to move. As a result, I'm going to do a highway drive to test foot fatigue over long time periods..

Daryl

 

[lowenbrau]

FWIW I believe the MR2 has a similar device for connecting the cable to the fuel system but it's cammed differently. I've been looking for one in the wreckers and will report back how it works if I ever find one.

Alberta is sorry to lose you Daryl. I'm jealous.

 

[ostacruiser]

Did you manage to snap any pics?

 

[Eric Winkworth]

You guys know you can use that thottle adjustment to help this, although it probably takes a little life out of you slippin your cltuch, Seems to work good for me.

 

[dieselDaryl]

Hey guys,

Sorry its taken so long to upload the pics.. here they are.. I've been running with this 'fix' for 4 months now and is pretty much eliminated the touchy throttle. I am super pleased with this mod..

Yes, you can use the hand throttle in some cases, but when crawling over logs, rocks, etc, I didn't find that it worked all that well..

Location of Throttle control:

Loooking sraight down from the top of the engine. The spring clips over two pins that have an indentation to hold it from vibrating off.

Modified spring length

*Editted by Stone to show pics on thread.

 

[snowking]

Hey guys,

Sorry its taken so long to upload the pics.. here they are.. I've been running with this 'fix' for 4 months now and is pretty much eliminated the touchy throttle. I am super pleased with this mod..
Modified spring length
http://www.infometrix.ca/photo/throttlespring/IMG_2942.jpg

Yes, you can use the hand throttle in some cases, but when crawling over logs, rocks, etc, I didn't find that it worked all that well..

Location of Throttle control:

Loooking sraight down from the top of the engine. The spring clips over two pins that have an indentation to hold it from vibrating off.

Mroning Daryl ,Thanx for the info, I will try it on my Hj61. Did you do any mods. to the hand throttle it self or did just leave that alone?
Rob

*Editted by Stone to show pictures on thread.

 

[VTCruiser]

interesting, i have not had sensitive throttle problems with my 1HZ, I actually find my go-pedal nice and stiff. Are the 1HD-T set-ups that different? Maybe you could swap springs from a 1HZ?

just throwing it out there, i haven't even looked at mine for comparison....

 

[crushers]

it really isn't the throttle that is the problem but the direct injection that causes the sensitivity. the HDT manual, 2LTE manual, 13BT manual and the 12HT manual show the same sensitivity...
the HZ,PZ,3B,2H etc do not have this concern...
cheers

 

[Greg_B]

it really isn't the throttle that is the problem but the direct injection that causes the sensitivity. the HDT manual, 2LTE manual, 13BT manual and the 12HT manual show the same sensitivity...
the HZ,PZ,3B,2H etc do not have this concern...
cheers

I believe it is more of a linkage issue. Play with the throttle cable at the top where the cable attaches, and you get get an engine to bounce. Do this right at the injection pump (making sure your hand is very solid) and it is a world of difference. In addition, The 12HT seems more prone to bounce off the bottom governer if the spring is weak or missing, causing the "bounce" to happen.

DI does seem more responsive at the bottom end, vs IDI. I think that is one of the reasons engine response (power curve) seems much smoother in the factory TC DI engines, vs a TC'd IDI 3B, 2H, or 1HZ.

I havn't noticed a problem with my 13BT bouncing.

hth's

gb

 

[Tapage]

very interesting .. never think in this issue when seen the throtle system of my 2H

 

[dieselDaryl]

I believe it is more of a linkage issue. Play with the throttle cable at the top where the cable attaches, and you get get an engine to bounce. Do this right at the injection pump (making sure your hand is very solid) and it is a world of difference. In addition, The 12HT seems more prone to bounce off the bottom governer if the spring is weak or missing, causing the "bounce" to happen.

gb

I think it’s a combination of three things:
-The throttle assembly itself is very touchy (I am amazed at how little movement of the arm bumps the RPM up. Literally just touching it)
-The lack of a second or bottom spring.
-DI is more 'torquey' at the low end (Wayne). Although like gb said, I haven’t noticed this in any of the 13BTs. I think it’s a contributing factor on the HJ61 rather than the main reason.

There are indentations for a second spring, so whether Toyota didn't include it on JDMs or the owners took them off, I don't know. Regardless, it is a major PITA on the 5spd 61s and I am hoping this helps some people

Snowking: no I Left the hand throttle the way it is. It sure is nice not to have to use the hand throttle to drive over rough terrain. It sure took away from a lot of the off road experience..

Daryl

 

[R2HKS]

it really isn't the throttle that is the problem but the direct injection that causes the sensitivity. the HDT manual, 2LTE manual, 13BT manual and the 12HT manual show the same sensitivity...
the HZ,PZ,3B,2H etc do not have this concern...
cheers

I beg to differ, my BJ42 with 3B has an extremely touchy throttle. In bumpy terrain I struggle with it a lot especially since my hand throttle is not working, kept using as cruise control and never checked it out why its not working now.

In fact a cure I came across were a certain pair of shoes the molded nicely and I could rest the edge of my foot on near the door.

I'll have to check and see whether I can add an extra spring because the throttle is very light and easy to press down. More travel in the pedal would help also.

 

[crushers]

I beg to differ, my BJ42 with 3B has an extremely touchy throttle. In bumpy terrain I struggle with it a lot especially since my hand throttle is not working, kept using as cruise control and never checked it out why its not working now.
.

now this is interesting, i have driven literally hundreds of 3Bs and never had the problem you are describing...
very interesting..

cheers

 

[beanz2]

it really isn't the throttle that is the problem but the direct injection that causes the sensitivity. the HDT manual, 2LTE manual, 13BT manual and the 12HT manual show the same sensitivity...
the HZ,PZ,3B,2H etc do not have this concern...
cheers

I too beg to differ. My 1HDT w/ 5 speed has no such lurching problems. Same throttle mechanism as a 1HZ. I have driven two HJ61s and the throttle sensitivity is immediately noticeable even on gravel roads.

Dave

 

[nickw]

now this is interesting, i have driven literally hundreds of 3Bs and never had the problem you are describing...
very interesting..

cheers

I agree, no major lurching problems on any truck have driven.
-My BJ60 never did it
-My girlfriends FJ55 (powered by turbo charged 3B) does not do it
-Nor her dads BJ60 with AXT turbo (allthough I did not drive. But I have passengered hundreds of KM of offroad)

My 1HD-T has done it a couple of times, allthough very minor, I doubt the passenger could even tell. Only me as a driver could probably notice. I might look at doing the spring fix on mine.

Cheers,
Nick

 

[crushers]

I too beg to differ. My 1HDT w/ 5 speed has no such lurching problems. Same throttle mechanism as a 1HZ. I have driven two HJ61s and the throttle sensitivity is immediately noticeable even on gravel roads.

Dave

the one i drove had the sensitivity espcialy on speed bumps or entrance curbs.
the gent i sold it to has never mentioned it so he might not feel it either...