Carb choke pin stuck

[Zaos]

Hi, I have a 1989 vmax with starting/staying on issues, I’m in the process of testing fuel compression and spark, while I was looking at the carbs I noticed one of the carb pins that pulls out for the choke was stuck, the rest open fine, I was wondering what the procedure would be to get this unstuck, I’m planning on rebuilding the carb anyways as I want to ensure it’s not a carb issue and it’s a old bike with unknown maintenance history, or would y’all recommend just dropping it in an ultrasonic cleaner.

 

[99YAMAHAVMAX]

Hi, I have a 1989 vmax with starting/staying on issues, I’m in the process of testing fuel compression and spark, while I was looking at the carbs I noticed one of the carb pins that pulls out for the choke was stuck, the rest open fine, I was wondering what the procedure would be to get this unstuck, I’m planning on rebuilding the carb anyways as I want to ensure it’s not a carb issue and it’s a old bike with unknown maintenance history, or would y’all recommend just dropping it in an ultrasonic cleaner.

Hopefully it is an outside enricher on the #2 or #3 carb-they can be taken apart and cleaned easily, just take note of each part-if not then taking the carbs completely part is not a bad idea if you are capable of doing so yourself--don't drop them in an ultrasonic cleaner without taking each carb completely apart---rubber doesn't agree with cleanser or heat.

 

[Fire-medic]

The enrichener piston can become stuck if you soak it in an ultrasonic bath, and do NOT purge all the liquid from the enrichener body on the side of the carb bodies. You can remove the gland nut and try a mix of ATF/acetone to loosen the piston (what you're calling the 'carb pin'). However, the shaft of the enrichener piston is very-small. The shaft is what the forked pair of followers on the enrichener rod actuate by. You can see it is very small diameter.

Trying any force to dislodge the enrichener piston is going to snap it. I do NOT recommend any heat from something like a propane torch to loosen the enrichener piston, because the potmetal of the carb body or the enrichener body which is held to the carb body by 2 screws can easily distort or even melt. If you look at a Yamaha fiche, those enrichener bodies are NOT available separately. The enrichener piston is still available, it costs > $50.

Multiple soakings and maybe careful use of a hot air gun may finally get the piston free, but this may be one of the times when you need to break the carbs into four separate bodies.

 

[99YAMAHAVMAX]

The enrichener piston can become stuck if you soak it in an ultrasonic bath, and do NOT purge all the liquid from the enrichener body on the side of the carb bodies. You can remove the gland nut and try a mix of ATF/acetone to loosen the piston (what you're calling the 'carb pin'). However, the shaft of the enrichener piston is very-small. The shaft is what the forked pair of followers on the enrichener rod actuate by. You can see it is very small diameter.

Trying any force to dislodge the enrichener piston is going to snap it. I do NOT recommend any heat from something like a propane torch to loosen the enrichener piston, because the potmetal of the carb body or the enrichener body which is held to the carb body by 2 screws can easily distort or even melt. If you look at a Yamaha fiche, those enrichener bodies are NOT available separately. The enrichener piston is still available, it costs > $50.

Multiple soakings and maybe careful use of a hot air gun may finally get the piston free, but this may be one of the times when you need to break the carbs into four separate bodies.

The enricher is held to the carb by 3 screws not 2. They will have washers not to be confused with the 3 that don't that connect the cut-off valve covers except for the ones that go to the #4 carb plastic cover.

 

[dannymax]

Trying any force to dislodge the enrichener piston is going to snap it. I do NOT recommend any heat from something like a propane torch to loosen the enrichener piston, because the potmetal of the carb body or the enrichener body which is held to the carb body by 2 screws can easily distort or even melt. If you look at a Yamaha fiche, those enrichener bodies are NOT available separately.

I have lots of them Philip, as well as complete rebuilt enricheners.

 

[Zaos]

The enrichener piston can become stuck if you soak it in an ultrasonic bath, and do NOT purge all the liquid from the enrichener body on the side of the carb bodies. You can remove the gland nut and try a mix of ATF/acetone to loosen the piston (what you're calling the 'carb pin'). However, the shaft of the enrichener piston is very-small. The shaft is what the forked pair of followers on the enrichener rod actuate by. You can see it is very small diameter.

Trying any force to dislodge the enrichener piston is going to snap it. I do NOT recommend any heat from something like a propane torch to loosen the enrichener piston, because the potmetal of the carb body or the enrichener body which is held to the carb body by 2 screws can easily distort or even melt. If you look at a Yamaha fiche, those enrichener bodies are NOT available separately. The enrichener piston is still available, it costs > $50.

Multiple soakings and maybe careful use of a hot air gun may finally get the piston free, but this may be one of the times when you need to break the carbs into four separate bodies.

Just so we are on the same page, I am talking about part #20 in this image

 

[Fire-medic]

The enricher is held to the carb by 3 screws not 2.

Yes, you're right. I was on a notebook which didn't have my VMax pics, and took a guess. I didn't look at a Yamaha fiche either before posting, thanks for posting the corrent screws #.

O.P.: yes, that's it.




dannymax to the rescue, for anyone needing a replacement enrichener piston or housing. [email protected] his email.

 

[Zaos]

Yes, you're right. I was on a notebook which didn't have my VMax pics, and took a guess. I didn't look at a Yamaha fiche either before posting, thanks for posting the corrent screws #.

O.P.: yes, that's it.

View attachment 90043View attachment 90044


dannymax to the rescue, for anyone needing a replacement enrichener piston or housing. [email protected] his email.

Thank you, if I do need to split open the carb is this a difficult task? I’ve always done all the work on my vmax and have plenty of tools, I’d plan on buying a rebuild kit if I have to go down that route anyways

 

[99YAMAHAVMAX]

Thank you, if I do need to split open the carb is this a difficult task? I’ve always done all the work on my vmax and have plenty of tools, I’d plan on buying a rebuild kit if I have to go down that route anyways

There are step by step threads on the site-not difficult if you are mechanically inclined.
I would take them completely apart to see exactly what needs to be replaced as there is no one kit for everything and quality kits are not cheap. Plenty of tools I hope consists of impact screwdriver with JIS bits and you will want to replace the screws with allenheads. Float settings are most crucial.

 

[MaxMidnight]

Thank you, if I do need to split open the carb is this a difficult task? I’ve always done all the work on my vmax and have plenty of tools, I’d plan on buying a rebuild kit if I have to go down that route anyways

Note that the screw heads are JIS NOT Phillips or x point. The correct driver minimises the chance of intercoursing the screw head..

 

[Zaos]

Note that the screw heads are JIS NOT Phillips or x point. The correct driver minimises the chance of intercoursing the screw head..

yup i have JIS bits, learned my lesson after striping every head on my yamaha virago, Thanks for the help going to dive into it if i dont end up selling it for a newer vmax lol.