johngofast
Over 1,000 Posts
Good luck. Post your findings.
Cant stop the fuel leaks
- Thread starter Deadfrednc
- Start date
Maritime
Over 10,000 Posts
make sure your valve seats are spotless, we had a leaking CRF and we adjusted float height 4-5 times before I finally looked at the seat, there was a small spec of dirt in there preventing the tip from seating and causing the leak, a thorough cleaning and leak averted.
Deadfrednc
New Member
I know I mentioned the seat being scratched earlier in this thread and I've mentioned it to other people as well. Why has no one touched on that issue or is it really not an issue at all
Flugtechnik
My bike is not transportation, it is a respite
I have seen a plastic non-adjustable float, but only in my lawn mower.
Again, I would suggest checking the float valve action with some actual gas running through them. This can be done on or off the bike.
I check mine on the bike. I shut the petcock. Remove the bowl. Hold the float up so the valve closes. Turn the petcock on. Nothing should come out. Slowly lower the float until fuel starts to come out. The point at which fuel starts to leak through the valve is your float height. I have a tool to measure mine and mine is adjustable. However, you should try this just to see if the valve is working properly.
A couple of times I got a small piece of dirt or rust stuck in the float valve seat and the bowl would overflow. Often, just removing the bowl and flushing gas through the valve will dislodge it.
Again, I would suggest checking the float valve action with some actual gas running through them. This can be done on or off the bike.
I check mine on the bike. I shut the petcock. Remove the bowl. Hold the float up so the valve closes. Turn the petcock on. Nothing should come out. Slowly lower the float until fuel starts to come out. The point at which fuel starts to leak through the valve is your float height. I have a tool to measure mine and mine is adjustable. However, you should try this just to see if the valve is working properly.
A couple of times I got a small piece of dirt or rust stuck in the float valve seat and the bowl would overflow. Often, just removing the bowl and flushing gas through the valve will dislodge it.
Maritime
Over 10,000 Posts
A couple of times I got a small piece of dirt or rust stuck in the float valve seat and the bowl would overflow. Often, just removing the bowl and flushing gas through the valve will dislodge it.
this was ours but the dirt was sticky so I had to use a toothpick to get it to flush out. it was a grain of sand or smaller and caused fuel to piss constantly. also, check the tips of the plunger part if they get bent or damaged they won't seal or seat right and let gas pass.
this was ours but the dirt was sticky so I had to use a toothpick to get it to flush out. it was a grain of sand or smaller and caused fuel to piss constantly. also, check the tips of the plunger part if they get bent or damaged they won't seal or seat right and let gas pass.
Maritime
Over 10,000 Posts
I didn't realize this was page 2, went back and read, you said you cleaned seats with a drill, did you change the V shape at all? even a little bit will make the tip of the plunger stop seating right on the valve, so would scratches, they would allow fuel past. Are the seats replacable? If so you likely need a new one on the carb in question.
Deadfrednc
New Member
So I'm assuming it's the scratch in the seat causing the leak cause in order to stop flow I have to use way to much pressure on the float valve. Luckily I just won a set of carbs on ebay that will hopefully be ok.
Deadfrednc
New Member
hey guys so I'm back with more results. I purchased a set of carbs they cleaned up very nice I re assembled them with the old parts minus I used my new set of float valves. the new carbs leak as well even worse than the others and Ive checked for trash in the seat and i made sure the floats would float. with the float bowls off I put gas to them raised each float by hand and they all shut off as they should. now I'm almost certain this makes no difference but ill mention it anyways just because, well I tend to be wrong sometime lol. as you can see in one of the pictures this bike came with a vacuum operated fuel shut off I'm running a cb750 tank on my bike that has a manual shutoff so I did away with that. There was a rubber T in between 1 and 2 and another between 3 and 4 rather than a T I just connected them with a straight piece of hose. I don't see where that would make a difference since once upon a time before the carbs leaked there wasn't anything there at all and I had no trouble. Keep in mind these floats can not be adjusted. there are pics I posted of the carbs earlier in this thread If you would like to refer back to them to see how this setup looks. thanks in advance for any help.
