Throttle on YM155D

[astromarmot-HT]

Greetings everyone, and Happy Father's Day to all the dads out there.

I have a YM155D with the foot pedal/accelerator, and right after I got it a few years ago, the foot pedal stopped working, as well as the throttle handle would only work in the forward/increase direction. As life often does, things got busy, and I've just been milking this baby by reaching around the to pull the connector rod to decrease the throttle or shut down.

Now that I'm trying to get this workhorse back into shape, I'm not finding any diagrams of how that throttle linkage should work. It appears there's a spring that might have broken that tied the whole shebang together, but I can't for the life of me figure out what went where, or how to spec a replacement spring. The shop manual I have doesn't show this fancy throttle/pedal assembly, just the standard one.

I don't have photos at the moment, but if needed I can go out and snap a couple of pictures to help.

Thanks for any insight y'all might be able to provide.

 

[winston-HT]

Here is a pdf you can down load that shows all components. <LINK_TEXT text="https://app.box.co...zravu7q7wsducjk/file/651208602127</LINK_TEXT>

 

[Ohyo-HT]

Spring
Code: H194200-01680

 

[astromarmot-HT]

<QUOTE author="winston"><s>

</s>Here is a pdf you can down load that shows all components. <LINK_TEXT text="https://app.box.co...zravu7q7wsducjk/file/651208602127</LINK_TEXT><e>

/e></QUOTE>

Thank you! That link only had through page 264 of the manual. The diagram for the throttle pedal assembly is on pg 361.

 

[astromarmot-HT]

<QUOTE author="Ohyo"><s>

</s>Spring
Code: H194200-01680<e>

/e></QUOTE>

Thank you!

EDIT: Unfortunately out of stock.

 

[Ohyo-HT]

<QUOTE author="astromarmot"><s>

</s><QUOTE author="Ohyo"><s>

</s>Spring
Code: H194200-01680<e>

/e></QUOTE>
Shows it in stock.

https://www.hoyetractor.com/PROD/194200-01680.htm

 

[Aaron-HT]

We have several of the 194200-01680 in stock.

 

[winston-HT]

<QUOTE author="astromarmot"><s>

</s><QUOTE author="winston"><s>

</s>Here is a pdf you can down load that shows all components. <LINK_TEXT text="https://app.box.co...zravu7q7wsducjk/file/651208602127</LINK_TEXT><e>

/e></QUOTE>

It shows on pages 71 thru 79 downloaded or just browsing it.

 

[astromarmot-HT]

Thanks y'all. I must have been looking at this before I had enough coffee. I apologize for having my head up where the sun don't shine.

 

[astromarmot-HT]

Now, I think I might at least be beginning to see where my problem might be. Looking at the correct pages of the parts manual(thank you Winston) I see that I might have some frankenstein version throttle pedal that's something between the England and Except England version(aftermarket pedal perhaps?). My little tractor looks more like the throttle assembly of the Except England 155D with the hook on the throttle handle, and the single front/rear throttle rod running forward, but it also has the throttle pedal. I might be experiencing two issues at once. The throttle pedal is EXTREMELY stiff, and I'm not sure where to actually lubricate it as the stiffness seems to be as much at the fuel control end as it is at the pedal end. I do believe now that I'm looking at it that the decompression rod may have come loose, and may have even departed the tractor. Will check when I can get away long enough to go out to the barn and take a look at it.

 

[astromarmot-HT]

Additional information. It appears that my tractor no longer has this decompression rod, but if it did, can anyone point me to where the indicated end would attach?
<ATTACHMENT filename="Yanmar Engine Control 1.png" index="1"><s>[attachment=1]</s>Yanmar Engine Control 1.png<e>[/attachment]</e></ATTACHMENT>

In the following image, I've located the decompression levers, but on my tractor, there is no linkage of any sort that is attached to them.
<ATTACHMENT filename="Yanmar Engine Control 2.png" index="0"><s>[attachment=0]</s>Yanmar Engine Control 2.png<e>[/attachment]</e></ATTACHMENT>

I sort of inherited this problem, so my history of what may or may not have been on the tractor and when is very limited. I know the first time I used it, I just throttled back with the pull handle all the way and the tractor would shut down. Now the throttle handle doesn't decrease throttle at all, I have to reach to the side to pull the throttle rod all the way back to kill the engine. The hook that was once attached to a decompression rod is there, but no rod, no link. I just don't know if in the time I was operating this thing if it ever was, or when everything was moving freely the idle was just set to where all the way back was enough and there was some kind of odd rigging that allowed the throttle hand lever to pull the regulator lever back far enough.

 

[Ohyo-HT]

Can you take some pics also?

 

[Ohyo-HT]

Different exploded view.

 

[astromarmot-HT]

Here's a couple of photos. Not as good as I'd have liked as a gullywasher came up just about the time I snapped the 2nd photo. Will try to get a short video of the movement tomorrow if I can. <ATTACHMENT filename="YanmarThrottle2.jpg" index="0"><s>[attachment=0]</s>YanmarThrottle2.jpg<e>[/attachment]</e></ATTACHMENT><ATTACHMENT filename="YanmarThrottle1.jpg" index="1"><s>[attachment=1]</s>YanmarThrottle1.jpg<e>[/attachment]</e></ATTACHMENT>

 

[astromarmot-HT]

So, on your first picture, the little hook doesn't attach to anything?

 

[Ohyo-HT]

<QUOTE author="astromarmot"><s>

</s>So, on your first picture, the little hook doesn't attach to anything?<e>

/e></QUOTE>
I don’t know about that little clip. I have just bought the 155 recently for parts that I needed to finish the 165. I’ve gotten the 165 fired back up today and learned a hard lesson after cranking on the 165 and getting nothing. There are different size throttle linkages, #8 in exploded view above, the one I had attached was to short and wouldn’t go wot. I unhooked it and controlled the linkage by hand and got it to start and run. Rookie mistake.

 

[astromarmot-HT]

I'm at a loss. I thought that little hook clip attached to something when my throttle failed to work in the decrease direction, but now I'm beginning to wonder if the whole thing is just way too stiff and the spring for the pedal isn't up to the task of returning the throttle back when the handle is back. Guess I'm gonna have to tear into it more to see if there's something I can degunk or lubricate to make things move again.