HJ61 Possible sensitive throttle fix

[odingski]

I was going through this thread. Got a lot of info. I was just wondering if anybody has ever thought of using an RC Damper to stabilize the accelerator? Just wondering.

 

[whirleybird]

Ive posted this on another thread. I made a couple of brackets with a small soft damper off a tool box lid. Works a treat off-road. My 12ht 60 (originally 2h) was almost undrivable on bumps before. I removed the pedal spring and it feels about the same

 

[ukaviator]

Thats a cool idea! Any idea what strength shock it is?

 

[Silveredition]

No where near as flash as a gas strut, but this is what I used to solve my throttle issue (apart from being sensitive, the engine would drop below idle and sometimes stall when off throttle). This throttle dampener ,(or dash pot) was found at a wrecker and I made the stainless bracket. All it does is slow the throttle for the last bit of movement back to idle. It does nothing when throttling up, but slows the return to idle.
Not great photos, but should be able to see it...
The engine is currently getting a full rebuild, but I may put it back on when done as it works well... will make a new bracket though, as this one looks dodgy!!!

 

[whirleybird]

Ah yes I’ve seen people install those on 2hs as well. Only reason I didn’t go that route is I wanted something to take the harshness out both ways. I’ve done some bumpy 4wding and it’s completely changed the way the car drives. So much better. @ukaviator im not sure of the strength and there’s no markings on it. It’s only deigned for a tool box lid so fairly soft. I have a few others laying around off Robinson helicopter doors but they have too much pressure, even old ones

 

[Winslow17]

Hey team, just thought it might be worth sharing this. I drew from your collective wisdom and odingski’s suggestion of an RC car damper and installed this today.

It works brilliantly. Provides just the right amount of damping on both opening and closing the throttle. No more kangaroo hopping when crawling, no more dipping below idle and nearly stalling when lifting your foot quickly. Damping can be changed by using different weight oil. Spring can be adjusted in situ, or changed for heavier/lighter springs.

I’ll wait to see how durable it is, but being all aluminium, it should last a while. Overall, I’m pretty happy with this mod.

FYI, it’s on a 12HT that we transplanted into an HJ60 to replace the tired 2H diesel.

 

[drenmaster]

@Winslow17 can you add any details on the bracket? Looks like you built a bracket to fit the shock. Really interested in somthing like this. I would love to stop using the hand throttle while being offroad..

 

[Winslow17]

@Winslow17 can you add any details on the bracket? Looks like you built a bracket to fit the shock. Really interested in somthing like this. I would love to stop using the hand throttle while being offroad..

Hi drenmaster,
I’ll attach a few more photos for you...

 

[Winslow17]

Okay. First things first, I extended the standard 12HT throttle cable bracket so it reached down further towards the throttle lever on the pump. This allowed me to use the 2H throttle cable without having to extend it (simply cut the fitting off the end and secure it into an aftermarket ball joint which you can see in the phots).

To extend the bracket, I cut it below the mounting holes, fabricated a piece of plate and welded it in. It still didn’t quite get me close enough to the throttle lever on the pump, and if I’d extended it further it would have hit the idle-up diaphragm, so I added a piece of 25mm x 25mm hollow section on the bottom to accept the throttle cable.

 

[Winslow17]

That piece of 25mm x 25mm hollow section provided me with the perfect spot to mount a bracket for the RC car shock absorber.

I just made the bracket from some more hollow section - two pieces back to back to make a clevis for the top shock mount - and welded it on.

 

[drenmaster]

@Winslow17 thanks for the info. Ill take a look at the 12h-t tomorrow and see how that compairs and maybe come up with a plan.

 

[Winslow17]

The lower connection is a piece of 1.2mm plate, bent around into a U shape to make the clevis for the lower shock mount. It is tack welded to the throttle lever, and my aftermarket ball joint stud is also bolted through it.

It extends the throttle lever by about 10mm to keep the bottom shock mount clear of the throttle cable and ball joint.

 

[Winslow17]

Just to complete the story, the shock absorber is an aftermarket unit for an Axial Yeti.

With the geometry of the brackets I made, I needed a shock/damper 120mm eye-eye, with 40mm stroke to still get full travel of the throttle lever.

It was a bit of mucking around, but well worth it.