Hand Throttle For Big Blue

[Gary Lewis]

Bob/Nothing Special has convinced me that a hand throttle would be helpful on our trip to Moab this summer. And he suggested this Terraflex hand throttle kit. I ordered it in and plan to start the installation after I get the clutch safety switch bypassed. So stay tuned...

[viven44]

Assuming it will be helpful in a scenario where both feet are occupied on brake/clutch, and one hand on steering. But wouldn't this soften the need for the clutch no-safety ?

[Nothing Special]

Assuming it will be helpful in a scenario where both feet are occupied on brake/clutch, and one hand on steering. But wouldn't this soften the need for the clutch no-safety ?

It definitely softens the need. But of the two mods I'd put the hand throttle well ahead of the clutch safety bypass. What I told Gary about the hand throttle is "A hand throttle isn't a necessity, but after 'wheeling with one I'll never 'wheel without one", while what I said about the clutch switch bypass was "I'll stop short of recommending this, but I'll offer it for your consideration".

But they really do address different issues. The hand throttle helps in starting on a hill, regardless of why you stopped. It's not at all uncommon to pick a line that didn't work the first time and have to back off and try again. Generally the engine didn't die so restarting isn't the issue. A hand throttle also is easier to hold steady than a foot pedal as you bounce over rocks. I use it quite a bit to set the idle higher to let the truck chug over obstacles.

Meanwhile the main use of the clutch switch bypass is to keep you from rolling back when you are restarting the engine. With a manual trans having the engine hold the vehicle you need to get on the brakes HARD before pushing in the clutch. With power brakes (especially hydroboost which is even weaker without the engine running) that's even harder. It's very uncommon for a driver to actually keep the truck from rolling backward, at least a little. And when it does it's usually pretty abrupt. That kind of sudden movement can really bring yelps out of passengers!

[Gary Lewis]

It definitely softens the need. But of the two mods I'd put the hand throttle well ahead of the clutch safety bypass. What I told Gary about the hand throttle is "A hand throttle isn't a necessity, but after 'wheeling with one I'll never 'wheel without one", while what I said about the clutch switch bypass was "I'll stop short of recommending this, but I'll offer it for your consideration".

But they really do address different issues. The hand throttle helps in starting on a hill, regardless of why you stopped. It's not at all uncommon to pick a line that didn't work the first time and have to back off and try again. Generally the engine didn't die so restarting isn't the issue. A hand throttle also is easier to hold steady than a foot pedal as you bounce over rocks. I use it quite a bit to set the idle higher to let the truck chug over obstacles.

Meanwhile the main use of the clutch switch bypass is to keep you from rolling back when you are restarting the engine. With a manual trans having the engine hold the vehicle you need to get on the brakes HARD before pushing in the clutch. With power brakes (especially hydroboost which is even weaker without the engine running) that's even harder. It's very uncommon for a driver to actually keep the truck from rolling backward, at least a little. And when it does it's usually pretty abrupt. That kind of sudden movement can really bring yelps out of passengers!

Well said, Bob. Exactly as I explained it to Janey.

I'm hoping that one of my spare speed control units has one of the beaded chains I can use to attach the hand throttle's linkage to the existing linkage. That seems the cleanest way to connect as then it can cause a bind if pushed in too far.

[viven44]

It definitely softens the need. But of the two mods I'd put the hand throttle well ahead of the clutch safety bypass. What I told Gary about the hand throttle is "A hand throttle isn't a necessity, but after 'wheeling with one I'll never 'wheel without one", while what I said about the clutch switch bypass was "I'll stop short of recommending this, but I'll offer it for your consideration".

But they really do address different issues. The hand throttle helps in starting on a hill, regardless of why you stopped. It's not at all uncommon to pick a line that didn't work the first time and have to back off and try again. Generally the engine didn't die so restarting isn't the issue. A hand throttle also is easier to hold steady than a foot pedal as you bounce over rocks. I use it quite a bit to set the idle higher to let the truck chug over obstacles.

Meanwhile the main use of the clutch switch bypass is to keep you from rolling back when you are restarting the engine. With a manual trans having the engine hold the vehicle you need to get on the brakes HARD before pushing in the clutch. With power brakes (especially hydroboost which is even weaker without the engine running) that's even harder. It's very uncommon for a driver to actually keep the truck from rolling backward, at least a little. And when it does it's usually pretty abrupt. That kind of sudden movement can really bring yelps out of passengers!

Thanks for the explanation. Agreed this mod looks like it's more likely to be used.

[Gary Lewis]

Thanks for the explanation. Agreed this mod looks like it's more likely to be used.

Ok, it is time to actually start on this project. And the first thing I'm told to do is to remove the knob off the shift lever. But I don't know how to do that, so I'm going to tag Shaun/salans7 'cause I think he knows.

Having said that, if it isn't easy then I'll slit the bushing they provide and slip it on that way.

Here's the knob and it is on a BW1345:

[Nothing Special]

Ok, it is time to actually start on this project. And the first thing I'm told to do is to remove the knob off the shift lever. But I don't know how to do that, so I'm going to tag Shaun/salans7 'cause I think he knows.

Having said that, if it isn't easy then I'll slit the bushing they provide and slip it on that way.

Here's the knob and it is on a BW1345:

Just food for thought, but I've usually had the hand throttle on the transmission shift lever. The exception to that was when I first was building Pluto I put it on the transfer case shift lever. I had it there for several years, but decided that it was just a little too far out of reach for my preference, so I ended up moving it back to the trans shifter.

[Gary Lewis]

Just food for thought, but I've usually had the hand throttle on the transmission shift lever. The exception to that was when I first was building Pluto I put it on the transfer case shift lever. I had it there for several years, but decided that it was just a little too far out of reach for my preference, so I ended up moving it back to the trans shifter.

Bob - How's Lesley?

As for being closer, on Big Blue the t-case shift lever is closer. And since there's far less movement of it than the shift lever I'm thinking that the t-case lever would be the best place to put the hand lever. Yes?

But I'm wondering about how/where to run the cable. The miserable instructions say to take it through the firewall, but why not go down the lever, through the boot, and up over the transmission and the back of the engine to the throttle body? No holes to drill.

And, speaking of throttle body, here's a mockup of how I plan to make the connection. The bottom cable is a spare throttle cable and the one that rides piggyback on it is a spare from the speed control. I've drilled the Nylon bracket that attaches to the throttle cable and run the bead chain from a Bullnose speed control through that hole. The inner cable, having come through the outer cable above, will wrap through the connector on the end and that aluminum ferrule will be crimped to hold it in place. And the connector on the end will let me take the slack out.

All of that is to ensure there's no binding of the throttle when not using the hand throttle. Does that make sense? Better ideas, anyone? http://www.garysgaragemahal.com/uploads/6/5/8/7/65879365/waving_orig.gif

[Nothing Special]

Bob - How's Lesley?

As for being closer, on Big Blue the t-case shift lever is closer. And since there's far less movement of it than the shift lever I'm thinking that the t-case lever would be the best place to put the hand lever. Yes?

But I'm wondering about how/where to run the cable. The miserable instructions say to take it through the firewall, but why not go down the lever, through the boot, and up over the transmission and the back of the engine to the throttle body? No holes to drill.

And, speaking of throttle body, here's a mockup of how I plan to make the connection. The bottom cable is a spare throttle cable and the one that rides piggyback on it is a spare from the speed control. I've drilled the Nylon bracket that attaches to the throttle cable and run the bead chain from a Bullnose speed control through that hole. The inner cable, having come through the outer cable above, will wrap through the connector on the end and that aluminum ferrule will be crimped to hold it in place. And the connector on the end will let me take the slack out.

All of that is to ensure there's no binding of the throttle when not using the hand throttle. Does that make sense? Better ideas, anyone?

The transfer case lever is farther to the left, so it's closer in that respect. But typically is a shorter lever and you have to bend down to reach it, while the trans shifter falls right into your hand. Maybe "closer" wasn't the right word. I like having it on the stick that I reach for all the time, so muscle memory helps me find it quickly and easily.

And yes, running the cable down the lever and through the boot seems like the right way to do it to me. Not only no holes to drill, but you don't need to leave a big loop of cable exposed in the cab so the stick can move. Just dress the cable down the stick and leave a little slack at the bottom, under the boot.

For hooking it up to the throttle body, most everything I comprehend looks good. What I don't quite get is how much adjustment you'll have. Adjusting it isn't that critical. If it's too tight it's bad as the throttle won't close all the way. But if it's too loose you just won't be able to open the throttle as far. I've found I can only go about 45 mph if I'm using my hand throttle in place of the foot feed. While it might be nice to have more throttle available by hand I've never felt it was really lacking.

the "most everything" comes from seeing the big open loop of cable you have between the ferrule and the ball chain. That's going to be a soft spring that you need to stretch out to get the throttle to open. I might just put the ferrule over the cable right as it comes through the end of the ball chain rather than put a loop in it. That might put more stress on the ferrule so it might pull off easier. But it will keep the system a lot stiffer.

(I was thinking I had a picture that shows where I have the hand throttle, but this is the best I could find. It sort of shows up at the bottom of the picture.)

https://forum.garysgaragemahal.com/file/n67185/DSC_0543.jpg

[Gary Lewis]

The transfer case lever is farther to the left, so it's closer in that respect. But typically is a shorter lever and you have to bend down to reach it, while the trans shifter falls right into your hand. Maybe "closer" wasn't the right word. I like having it on the stick that I reach for all the time, so muscle memory helps me find it quickly and easily.

And yes, running the cable down the lever and through the boot seems like the right way to do it to me. Not only no holes to drill, but you don't need to leave a big loop of cable exposed in the cab so the stick can move. Just dress the cable down the stick and leave a little slack at the bottom, under the boot.

For hooking it up to the throttle body, most everything I comprehend looks good. What I don't quite get is how much adjustment you'll have. Adjusting it isn't that critical. If it's too tight it's bad as the throttle won't close all the way. But if it's too loose you just won't be able to open the throttle as far. I've found I can only go about 45 mph if I'm using my hand throttle in place of the foot feed. While it might be nice to have more throttle available by hand I've never felt it was really lacking.

the "most everything" comes from seeing the big open loop of cable you have between the ferrule and the ball chain. That's going to be a soft spring that you need to stretch out to get the throttle to open. I might just put the ferrule over the cable right as it comes through the end of the ball chain rather than put a loop in it. That might put more stress on the ferrule so it might pull off easier. But it will keep the system a lot stiffer.

(I was thinking I had a picture that shows where I have the hand throttle, but this is the best I could find. It sort of shows up at the bottom of the picture.)

https://forum.garysgaragemahal.com/file/n67185/DSC_0543.jpg

Ok, "closer" threw me off, but I see what you are saying about muscle memory. However the ZF boot is actually two boots that fit very tightly, so I'm not sure I want to take the cable down through that.

As for that loop, I left it loose as I don't want to kink it since it might not go through the outer covering then. But yes, the aluminum ferrule will go right near the bead connector. I tried to put the ferrule in the bead connector but it won't go and, as you said, that would put more stress on it, so I'm thinking that a tight loop is the way to go.

Thinking about adjustment, my hope is the have just a little slack with the manual throttle all the way down, and it'll take some movement to raise the RPM. The combination of the beaded chain and knurled adjustment you can see at the end of the outer sleeve should let me dial it in. But I have no idea how much I'll be able to raise it - hope it is enough.