Hi All

A little while ago I got a 600 Hurricane that had been left sat for a few years, So a couple of months ago I put some fresh fuel in the tank to see if it fired up and it didn't. I got fed up with it and left it.
Now I've gone back to it and found out the problem was that water had got into the tank and the rest of the fuel system.

So far I've cleaned the carbs, replaced the fuel pump and running a hose from the inlet to the pump into a fuel can sat on the floor next to the bike.

When cranking the bike over it will sound like its trying to start but thats all, if I pull slightly back on the throttle it will stop trying all together.

But I did pour a spoon full of fuel down each the carb inlets which made the engine fire up. When it is running it wont idle and I have to keep the throttle open to keep it running. Pulling the throttle back the engine will rev up as it should and sounds sweet its just at idle it sounds rough.

Now to my question....
Does anybody know what could cause this problem be or is there something I'm missing??

One thing I did notice was if I were to partly cover the inlet to one of the carbs the engine would rev up on its own which I found odd.


P.s. sorry for the long write up but trying to give as much back ground as possible.

Thanks Dave

 

I'm an F3 guy, not a Hurricane guy so what I'm about to say may not be applicable, so take it with a grain of salt.
You said you have a can of gas on the floor next to the bike. What happens if you elevate the can and hose to be above the fuel pump. The pump may not have enough oomph to draw from the can if it's below the pump. When I work on my bike or a friends, I have a motion fuel bottle hanging from a step ladder. It kind of looks like the bike has an IV attached to it.

 

That would make sense.
I did test the pump by not connecting the outlet and cranking the engine over and it seemed to pump the fuel in pulses which could be why it tries to start.
Plus when I partly cover the intake to the carb it runs better as it starts pulling fuel up due to the high vacuum.

Its something I'll try later

 

You probably need to go back into the carbs and really clean out the choke enrichment circuit passages. They are pretty tiny and clog very easily. Ask me how I know...

 

I put a small tank above the hight of the carbs and after a bit of trying I got the bike to start. It wont idle much lower than 1500rpm and I'm having to use a bit of throttle to make it do that.

I gave all the jets a good clean but I now you've said give it a really good clean makes me think I've made a little boo boo.
1: what jet controls the choke enrichment circuit
2: what is the jet that screws in next to the main jet and should you be able to see through the from the bottom all the way to the top?

Thanks Dave

 

Sounds like you need to download the manual so you can visualize what jet does what. I went through the long neglected carbs on my bike four or five times before I had the bike running well.

https://cbrforum.com/forum/cbr-600f-...1990-a-128286/

You should be able to see light thru the jets to confirm that they are clean. The choke enrichment circuit is not a jet, it's in the passages of the carb itself. You can pull the choke lever and watch what moves on the carb, and figure out where the enrichment circuit is inside the carb body. Basically you need to keep at the cleaning until all the nooks and crannies are clear. And you need to have the pilot circuit adjusted properly though, in my experience, getting in there and screwing around with the adjustments on a bike that was running OK before is probably a mistake until absolutely certain you have the carb completely cleaned out first. You are there when the the bike will run cold with the choke on and can be set to idle smoothly at about 1250rpm once warmed up.

Also be sure that the carb boots are air tight. They commonly deteriorate with time, causing a big vacuum leak that will really screw up performance.

 

After my last post I stumbled across the download for the manual which was a big help.

I've pulled the carbs off again and stripped them down, this time I've cleaned the slow jet (Now I can see all the way through it).
I'm going to blow through all the tubes in the carb with the air line again just to make sure they are clear.

I do think the blocked slow jets were the main problem so I will give it a go later.

Thanks Dave

 

choke enrichment plungers arrowed mine were seized wich snapped the cable my guess on ur problem would be blocked idle jets