Kangaroo-engine ! (1 Viewer)

[marting]

I've had this problem since i got my car (HJ60) Thought i might try to get rid of it now, before i convert to turboism.

At low rpm 1000-1500 in high gears it's very hard to accelerate smoothly.. It "juggs" and "jerks" and wont pull cleanly.. I can work my way around it by stepping off the gas and slowly repressing it. I kinda have to carefully get it going
If i just leave my foot on the pedal the kangaroo-effect gets stronger and stronger
So when i slow down to f.ex pass a pedesterian, a horse or just slow down to below 60km/h for any reason, I'm forced to shift to third when i should be able to just coast along at 1000-1200 rpm in 4th (down to 45-50 km/h) and slowly gain the speed back

No smoke.

Someone told me he had the same problem and it was solved by changing all the hoses that go from the fuel-tank to the "diesel-vapour thingy" inside the "wall" next to the filler-hole. ( i call it the squid, cause it looks like one)

Any other ideas?

hmm.. what else can i add here....
The injectors are new.
The primer(hand)-pump will leak when pumped (when unsrewed)
It starts easily and otherwise runs just fine

What does the "squid" actually do?
Anyone else had this problem?
Easy fix? (yes please)

 

[roscoFJ73]

IMO ,the low rpms you mention shouldnt be used in the high gears.
I think the lowest rpm I would use in 3rd would be around 1500.
Anything less is 1st and 2nd gear only.
Try keeping the rpm betweent 1500 to 2000 .
The "squid" is a breather,most cruiser models got them around 85.

 

[Tapage]

Weird .. are you still using your EDIC relay and motor .. ?

The 2H is a smoth reliable engine .. I never have a behivor like that, I can cruiser my engine in 4th close to 1500 rpm withoud hesitation ..

 

[ozwallaby]

Since I can see 2 real kangaroos out my window as we speak, I better have a go at this one. I doubt the problem is your "squid". I think it's more likely wear in the rear tailshaft/diff. For a relatively easy test, you can remove the rear tailshaft, put the transfer case selector in 4h, engage the front hubs and take it for a drive the same way. If the "jugs n jerks" stop it's most likely wear in the rear diff or maybe the rear tailshaft. If this doesn't improve things, I'd have to say the motor is not quite reving enough, as Rosco advises. You may even have 3.7 (tall) diff ratios, which would make it harder for your vehicle to accellerate smoothly from these revs. An even quicker/easier test to see if you are on the rite track. Put the handbreak on, gearbox in neutral, and get under the car and see how much you can rotate the rear tailshaft by hand. Excessive play, points to a worn rear diff.. You could then do the shaft removal and see if it improves as I said before...

 

[RufusTheDufus]

What size tires do you have? Are they taller than stock?

 

[prado t]

REAL SIMPLE, you are lugging it, DONT! Your 2H does not have a turbo, even my 13B-T will do that because it is just too low of an RPM for the load.

 

[Tapage]

I'd have to say the motor is not quite reving enough, as Rosco advises. You may even have 3.7 (tall) diff ratios

Good advice .. if it's posible that you have a front 4.11 set and a rear 3.70.

 

[marting]

Thanx for the input guys..I dont strongly disagree with any thing you said.. shifting down is what i do ofcourse, but i still think a 4 liter engine should be able to gently accelerate from atleast 1300
There might be some play in the rear diff. I'll look in to it.
I think i have the tall diff-ratio The axels are stock (to my knowledge)
I run 32" tires

Prado T; I would agree if all it's "brothers" were just the same, but i know that not all people have this problem, and I have tried a 60 that was much worse.

I'll see what happens when I turbofy

 

[Henry James the 47th]

I'm having the exact same problem on my truck, which also has a 2H. It's very hurky-jerky at low rpm's in 1st and second gear, also reverse, especially when traversing over rough potholed ground. I thought it might be something to do with the throttle linkage, perhaps stiffer return springs are needed on the linkage?

It's is not a 'lugging the engine' issue. I've heard about this problem in another thread from a while back. I did a search for it but nothing came up.

I have a 2.5" exhaust, new fuel filter, new injectors, yada yada. I think it is a throttle cable/linkage/spring issue.

 

[crushers]

you are asking a lot of an engine to lug it down to 1000 rpm in a higher gear. you are also askign for that same engine to say "bye bye" due to the unneccesary load you are putting on it.

think of it this way, an engine is designed with a torque rating at a certain rpm, this is the best rpm for shifting and cruising. i am sure Dougal can explain this better using some formual than i can but i am going to stumble through it. picture the multiplication of the gearing to the engine power, 1st gear is 4.8 X your torque.... much easier for the engine to move that weight from a stopped or slow speed than 4th gear which is 1 X your torque.
you are also straining the clutch, ujoints, and the con rod bearings etc. the easier everythign turns the longer your engine is going to last...
also install a pyro and look athe difference of the heat being generated when lugging an engine and one that is running efficiently... you are causing HUGE amounts of heat that is needing to exit the head and it isn't happening so you are taxing your cooling system as well.
keep it up and you will be replacing a head. you will be replacing a clutch, you will be replacing ANY of the weak links from the engine to the wheels.
the idea of lugging a 5500 lb vehicle is not wise for ANY reason. you might think you are saving fuel but in reality you are not AND you are causing more problems than you might realise.

Henry, are you thinking of the "sensitive throttle issue" of the 12HT? that is not a problem on a NA non-direct injected engine.

 

[Henry James the 47th]

I'm in agreement as far as not lugging the engine goes. Definitely.

"Henry, are you thinking of the "sensitive throttle issue" of the 12HT? that is not a problem on a NA non-direct injected engine."

This problem seems very similar to that. I have a slightly non-standard set up, so the cause may well lie in there. My engine came out of an HJ60 with the automatic. I took the auto off and put on the H41. I kept the engine's auto-specific injection pump, as is doesn't use an EDIC set up. I liked the simplicity. So my throttle cable goes directly to a lever on the injection pump. The engine is shut off by cutting the air, not the fuel.

One thing i removed in the conversion to the manual tranny was the cable and linkage going from the throttle linkage over to the auto trans. Perhaps that stuff helped to dampen down the throttle response.

I have only a few theories to go on at this point, bit it does sound a bit like the problems we have read about with the 12h-T in that regard. I'll do another search on the forum to see what I can dredge up. If anyone has the links, post them up please.

 

[Henry James the 47th]

Here's one link:

https://forum.ih8mud.com/diesel-tech-24-volts-systems/172983-throttle-dampening.html

Here's another:
https://forum.ih8mud.com/diesel-tec...-potential-hj61-5spd-touchy-throttle-fix.html

and one more:

https://forum.ih8mud.com/diesel-tech-24-volts-systems/150972-12-ht-surge.html

Seems like common problem, across a variety of vehicles, but mostly confined to the 12H-T. It has the same type of pneumatically governed injector pump as the 2H with auto...(there's a clue in there somewhere perhaps?)

too bad those old posts have had their photos deleted, as i would love to see some different attempts at solving the problem.

 

[marting]

you are asking a lot of an engine to lug it down to 1000 rpm in a higher gear. you are also askign for that same engine to say "bye bye" due to the unneccesary load you are putting on it.

I don't drive around with my foot to the floor lugging it like crazy
The lugging oucurs at rpm's that I think is just a tad too high for a downshift.as i said at around 1300 wich is as low as I'll go. .on flat roads and around soft bends.etc.
I'm not really putting a lot of load on the engine when it happens, it's more like when i step of the gas and back on it.. the transition is hard to get smooth..
I just slow down a bit and shift down.

But lots of engines, even small petrol engines, can pull evenly from 1000 rpm.. maybe not hard, but smoothly

I agree that it certainly cant be good for any part of the car to jerk back and forth like that, so i try to avoid it..

Man I wish my 60 had 6 gears

I guess i could revv my engine a little higher.. It also has a crappy old broken exhaust that might be a bit restrictive. .. and the filters are getting a change this week..

Turbo build-up and major service next week so we'll see how it turns out..

 

[Henry James the 47th]

Problem solved*

*problem solved, at least in my case with my particular product.

Having read the various threads discussing the twitchy throttle problem, I took a close look at what the linkage was, and realized that the problem really is the throttle snapping back and forth, at the very bottom of the swing, What was needed was not simply higher spring rates, or more springs. If there was only one spring there, and it was tired, or both springs and they were tired, then it would make sense to do something about the throttle return springs.

What was really needed was some sort of device to dampen the lower swing of the throttle actuator arm. I was describing the problem to a friend, and he mentioned that gas cars with fuel injection have a dampener just like I described. I went over to a 1989 Mazda 323 parts car I have, which happens to be fuel injected, and lo and behold there was this neat little device. It has a white spring plunger that travels slowly, as if in oil, and it slows the snap back of the throttle arm at the bottom of the swing.

I removed the part and set to work figuring out a way to mount it.

My truck has a different arrangement than a factory rig set up for a 4 or 5 speed, but i imagine this solution could be adapted to a wide variety of different throttle actuator arms and spring set ups.

First off, here's a couple of pictures of the part I picked off the Mazda. I'm sure there are Toyota parts that could be just as easily worked with.

 

[Henry James the 47th]

here's a pic of the the throttle actuator arm. In my part's case, I chopped off part of it, as it was associated to a cable going to the auto trans, which is no longer the set up. I needed to bend the upper stop tab on the top of the arm (uppermost in the picture) a few degree in rotation as i needed to place the dampener out of the way of the springs.


Second picture shows the double spring arrangement at the linkage, after the actuator arm is removed. Note the bracket that bolts to the back of the injector pump and holds the ends of the springs.

 

[Henry James the 47th]

I started making up a bracket, using the existing bracket that holes the end of the two tension springs as a template. By sandwiching the bracket i made in behind the stock bracket, it also moves the stock bracket slightly away, which increases the spring tension a little bit.

It took an hour or two of fiddling and adjusting to get the bracket configured the way i wanted.

 

[Henry James the 47th]

Here's a close up of the dampener. It really solved the problem for me, , and the engine rev down is noticeably smoother. The odd time that the throttle would drop from, say 3000 revs down to idle, the drop seemed so quick that my engine would cut out sometimes, requiring a restart. That is now a thing of the past.

It would be cool to see if others with this throttle problem could use the above solution in some similar manner!

I could bling it out a bit by getting a new dampener (I wonder what they are technically referred to?), but I'll run with this one a while and see how it does. Maybe it's not fully tweaked yet, but so far so good.

 

[marting]

Good job Henry!

So your butterfly flapped it's wings when close to shut?

To be honest that is exactly what it feels like on my car to..
I'm not saying the jugging has nothing to do with me reving to low... but it could be more than one thing.

When i let go of the throttle and press the clutch the rpm drops down fast and dips under 500 before stabilizes at 600rpm..A smoother down-revving would be nice. I guess any sort of small damper would do the trick.. I can get some of the kind that prevents cabinets-drawers and doors from slamming..

 

[crushers]

nice solution...
i missed the setup in your truck...i assumed it was factory, my bad.

 

[roscoFJ73]

I'm not saying the jugging has nothing to do with me reving to low... but it could be more than one thing.

Most likely. Mine will do it sometimes if I drive carelessly and I suspect it is in the drivetrain in lots of places