FT404 Hand throttle wire broken

[traktorz]

During a plowing session this weekend, at the last opportunity before the winter arrives, the hand throttle wire broke.

On our FT404, the hand throttle lever is on the right hand side mud guard. It is capsuled in a plastic shell with no visible bolts or nuts to open it. I have to bring a torch light with me to see if I can open it to inspect what's the problem.

I think this is a generic throttle lever, that you find on other Chinese tractors as well. If anybody has any hints on opening and repair the hand throttle lever, I would appreciate it.

[traktorz]

Well, it was quite easy to remove the plastic cover with a screwdriver through the top lever slit. The cover was attached with three plastic pins.

Here I found the wire broken, so I need to order a replacement. How can we make the wire last longer? Using white lithium grease with PTFE?

[PJ]

Here's a copy of my 604s throttle diagram. I would lube the cable with a dry lubricant, like graphite of similar type before installing it in the outer casing. You may copy this and blow it up if you like. PJ

[traktorz]

Nov 2, 2009 9:04:56 GMT -5 PJ said:

I would lube the cable with a dry lubricant, like graphite of similar type before installing it in the outer casing.

Thanks for the appreciated recommendation of using graphite, since I think that will work OK even in cold weather. A replacement is on the way, but I'm not sure it's only the wire or the assembly.

[PJ]

Nov 3, 2009 1:33:05 GMT -5 traktorz said:

Nov 2, 2009 9:04:56 GMT -5 PJ said:

I would lube the cable with a dry lubricant, like graphite of similar type before installing it in the outer casing.

Thanks for the appreciated recommendation of using graphite, since I think that will work OK even in cold weather. A replacement is on the way, but I'm not sure it's only the wire or the assembly.

Your very welcome. I knew that you are in a colder part of the world and that's the reason I recommended Graphite. I don't know if it's available in your area, but they make a graphite spray which seems to stick a little better while re-assembling some parts. The liquid carrier in the can evaporates fairly quick and leaves just the lubricant in place. Hope all works out for you. PJ

[rayh]

This is a common problem on this style of throttle assembly. I say it is purchased from a jobber in China and used on many different tractors. I have the same assembly on my DF 554 DONG FENG and had the same problem coming. It was hard to push the throttle open and I could tell something was binding inside. I removed the cover and seen the cable anchor and lever were not inline and causing great pressure at the end of the tube. I cut the anchor loose and rewelded it inline and now it is completely different to use. Works freely.

[3RRL]

It looks like the wire got frayed and broke.
Could be a result from the inside diameter of that sheath having a sharp edge or burr on it? I'd polish that and add a radius all around the inside and use the lube as suggested.
Rob-

[traktorz]

Nov 4, 2009 11:49:20 GMT -5 rayh said:

This is a common problem on this style of throttle assembly. I say it is purchased from a jobber in China and used on many different tractors. I have the same assembly on my DF 554 DONG FENG and had the same problem coming. It was hard to push the throttle open and I could tell something was binding inside. I removed the cover and seen the cable anchor and lever were not inline and causing great pressure at the end of the tube. I cut the anchor loose and rewelded it inline and now it is completely different to use. Works freely.
i302.photobucket.com/albums/nn111/RayH6/Mod1.jpg
i302.photobucket.com/albums/nn111/RayH6/Mod2.jpg

Thanks for your illustrative recommendation.
I agree it's a design flaw and can imagine a much smoother operation after your modification tips.

We've received the replacement assembly by mail, including both the handle and the wire. However I need to refresh my welding skills, but now I've an extra assembly to experiment the recommended modification on.

[traktorz]

Nov 4, 2009 12:00:19 GMT -5 3RRL said:

It looks like the wire got frayed and broke.
Could be a result from the inside diameter of that sheath having a sharp edge or burr on it? I'd polish that and add a radius all around the inside and use the lube as suggested.
Rob-

First the hand brake wire broke and now the hand throttle wire.
I'll see if I can remove the throttle wire and add a radius to and polish the wire sheath edge. Thanks for the tips.

(On the hand brake wire, the mountings were cramped or pressed onto the wire, so it's not possible to remove the inner wire.).

[PJ]

Rayh and Traktorz, Thanks for the tips and photos! Now you've got me curious. I've got to look at the one on my tractor to see if it's the same design. If so, then modifications are in order. PJ