Carb Rebuild

[marksaunders]

Just ordered Randakk's carb rebuild kit for my 85 Interstate. I had running issues at the end of last year. Wish me luck.

[BigBro]

Just take your time, take lots of pictures (to jog the memory) and be sure to keep the carbs and their parts separated to ensure the parts go back in the same spots.

There are a lot of good tutorials and tons of help around the various sites to help out.

Don't be afraid to ask many of us will offer advice.

[admin]

Good luck and don't forget that a good carb rebuild starts with checking the gas cap and vent, the tank for rust and leaks, the hoses (they get old and fall apart inside,) fuel filter and fuel pump (pressure and volume) and then breaking down the carbs for inspection. Any other way and you are wasting your money on rebuilding the carbs.

[marksaunders]

The carbs haven't been touched before. I'm going to replace the fuel lines and add a new Randakk's filter.

[old gold]

I pulled the carbs off my 85 to check for dirt or other problems. I learned a few things before everything was back in place.

1. Take pictures of the complete assembly (top & bottom views) or find a picture or schematic on the internet showing the hose routing before you take it apart
2. The original hoses will be deteriorated/split/broken, so plan on putting in new vacuum and fuel lines.
3. After everything is together, carb synchronization will be required, so locate the tool before you start. If you don't have one, you can build one using PVC pipes and clear plastic tubing for under $30. Plans are available on the web.
4. The vacuum line from the #4 carb goes to the ignition module. The vacuum line from the base of the #4 carb inlet tube goes to the slow air valve. Don't reverse them.
5. Pulling the spark plug wires up out of the way makes the job easier, but mark which cylinder they go to. If you get a backfire upon startup, the wires aren't right.

[marksaunders]

Does anyone have a photo showing how to set the float height? My manual isn't very clear.

[BigBro]

Don't know if it is correct or not but here is what I did.
   

The plastic card was cut to the amount that should be correct setting. Hence my measurement tool.
The float needle valve (silver in the pic) has a spring in it. That is not supposed to be compressed just resting the needle against the seat. That means you kinda have to measure it at an angle not laying flat like this picture. You should just be able to slide your tool over the float when it is just setting against the needle seat.

I hope that helps. Someone else may be able to explain it better than I have.

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[admin]

Don't know if it is correct or not but here is what I did.


The plastic card was cut to the amount that should be correct setting. Hence my measurement tool.
The float needle valve (silver in the pic) has a spring in it. That is not supposed to be compressed just resting the needle against the seat. That means you kinda have to measure it at an angle not laying flat like this picture. You should just be able to slide your tool over the float when it is just setting against the needle seat.

I hope that helps. Someone else may be able to explain it better than I have.

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That's a great idea to use the card like that. I usually use calipers, but, your way looks a lot easier.

[BigBro]

Why Thank You. Since I was doing these across a few days when I came to this I wanted something that would give me the best chance of being consistent. Had that used empty Manufactured Rebate card all ready for the Shredder and thought why not. It actually worked out pretty well I thought. Not exactly perfect but it did allow a setting that was relatively the same way every time.

[marksaunders]

Carbs are back on and the bike is running great. The insides were pretty clean. It's amazing how much crap my ultrasonic cleaner gets out. The main issue I found all four floats were set to lean. All of the vacuum hoses were bad also. I used a Morgan Color Tune to set the carbs. What a simple process to get them dialed in. A few more fixes and it will be ready for the road.

[marksaunders]

I'm having an issue with a fuel line leaking. It's the line for the left side carbs. I've tried a spring clamp with no luck. I'm going to try a screw clamp tomorrow. I guess I'm wondering what clamps other folks have used.

[admin]

Are you sure the hose is the correct size? If you have tried carefully pinching the spring clamp with no luck then you might try this: .035" stainless mig welding wire or similar and twist it tightly until the leaks stops. Most welding shops would likely give you a foot of it for no charge.

[marksaunders]

I ended up using a small screw clamp. Back together and running great.......