All,
An old subject revisited. My 79 is having problems from cold start after sitting for a longer period of time. Starting after a few days is fine, a week still ok. Two weeks or more is getting a real problem.
I have an aftermarket vacuum unit fitted on my machine to be on the safe side for vapour lock & bend rods.
There were some ideas posted on the board before. A visitor mentioned the fitting of a pressure add in the vacuum line. Could any of you share experiences.
It will als be interesting to hear if anyone has been successful in fitting an electronic fuel pump or the likes.
Any information will be much appreciated.
Hard starting
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mikep7982
Frank,
Same deal on my 82. A clue presents itself in the fact that I can't flood it no matter what I do during the startups after sitting. I am thinking that the bowls are empty and to fill one must generate some vacuum to activate the valve then wait for fuel to flow.
Maybe we need a priming system sort of like on my weed eater.
Mike
Same deal on my 82. A clue presents itself in the fact that I can't flood it no matter what I do during the startups after sitting. I am thinking that the bowls are empty and to fill one must generate some vacuum to activate the valve then wait for fuel to flow.
Maybe we need a priming system sort of like on my weed eater.
Mike
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Dave Ditner
- Forum Regular
- Posts: 132
- Joined: Sat Mar 08, 2003 7:02 pm
- Location: Oxford, Michigan except for winter, Wildwood Florida then
hard starting
Want to fix that problem???? Find the vent line from the fuel shut off. It's easier to find for sure if you pull the tank but you really don't have to. 
If you're careful you'll find it just by removing the rh side cover. The vent line runs from the shut off down behind the clutch housing and terminates just below the hose clip on the right side of the bike. It's about 1/4" in diameter. Pull it out of the clip and bring it up to about the side cover. A slight pressure applied to the vent side of the diaphragm is just like vacuum applied to the other. Vacuum is supplied from the number 3 intake and it really ain't much when your cranking it with the starter. 
Now that you've found the end of the vent line, go to your nearest medical supply store and buy a replacement pressure bulb for a blood pressure cuff. They come in a couple of sizes, and have check valves built in. Get the small one. Cost about $5.00. On the way home stop at an auto parts store and get a 1/8" x 1/4" vacuum line adaptor. Plug the 1/8" end into the pressure bulb. Plug the other end into the vent line ane pressurize it
slightly. If it won't hold pressure it's probably because the vent line is cut. Start clipping it off a small piece at a time (about 2") until you get pressure to hold. The vent hoses are usually cut near the bottom. Once you get the pressure to hold, and remember it doesn't have to be much, hold it for 3 or 4 minutes. The do the normal twist the throttle 5 or 6 times, go to full choke and crank.
Should start much sooner than previously. Now all you have to do is curl up the line under the rh side cover and it's there every time you need it.
If you're careful you'll find it just by removing the rh side cover. The vent line runs from the shut off down behind the clutch housing and terminates just below the hose clip on the right side of the bike. It's about 1/4" in diameter. Pull it out of the clip and bring it up to about the side cover. A slight pressure applied to the vent side of the diaphragm is just like vacuum applied to the other. Vacuum is supplied from the number 3 intake and it really ain't much when your cranking it with the starter. Now that you've found the end of the vent line, go to your nearest medical supply store and buy a replacement pressure bulb for a blood pressure cuff. They come in a couple of sizes, and have check valves built in. Get the small one. Cost about $5.00. On the way home stop at an auto parts store and get a 1/8" x 1/4" vacuum line adaptor. Plug the 1/8" end into the pressure bulb. Plug the other end into the vent line ane pressurize it
slightly. If it won't hold pressure it's probably because the vent line is cut. Start clipping it off a small piece at a time (about 2") until you get pressure to hold. The vent hoses are usually cut near the bottom. Once you get the pressure to hold, and remember it doesn't have to be much, hold it for 3 or 4 minutes. The do the normal twist the throttle 5 or 6 times, go to full choke and crank.
Should start much sooner than previously. Now all you have to do is curl up the line under the rh side cover and it's there every time you need it.
Davey
9 Xs: 4-79s, 1-80, 1-81 and 3-82s
9 Xs: 4-79s, 1-80, 1-81 and 3-82s
