1980 tomos Bullet stops running when hot

Mark Scherping /

My 1980 tomos stops running, like it runs out of gas when the temperature warms ups. The plug is dry. It happen last year and I replaced the encarwi with a deletro this spring and ran good, until the weather got warm. I try starting it with the gas cap off, doesn't help. It will run slight with the choke on for a few seconds. I replaced the condensor 4 years ago. Any help will be greatly appreciated.

Thank you.

Re: 1980 tomos Bullet stops running when hot

My guess is that the float needle in the carb is getting stuck. It might slowly trickle which is why the carb has a full bowl of gas when started but runs dry before more fuel can go into the bowl. Check the float needle. If it feels sticky or super squishy then replace it. If it is not that then perhaps your gas cap is not venting as it should and causing a vacuum. Two easy and cheap things to try first.

Re: 1980 tomos Bullet stops running when hot

Mark Scherping /

Thanks, I will try it.

Re: 1980 tomos Bullet stops running when hot

Last thing to check would also be to replace your spark plug. Could be on it's way out and gets you started but fails once hotter.

Re: 1980 tomos Bullet stops running when hot

Mark Scherping /

Will put a new plug in. Would vapor lock due to a faulty gas cap only happen on 70 degree weather? Two weeks ago I drove 13 miles in 55 degree weather that was over cast with no problems.

Re: 1980 tomos Bullet stops running when hot

♣Slew Foot♣ /

The jet might be clogged.

A shitty air filter...

Re: 1980 tomos Bullet stops running when hot

> ♣Slew Foot♣ Wrote:

> -------------------------------------------------------

> The jet might be clogged.

>

> A shitty air filter...

Check the jet for sure! If you take a very thin wire you can push out any gunk. Just be careful not to scratch the jet too hard you do not want to accidentally alter the size of the jet. An easy to come by small wire is the innards of a brake cable. Just unwind one of the strands a short length, cut it off and it will clear out a gunked up jet in a pinch.

Re: 1980 tomos Bullet stops running when hot

Or , a wire brush bristle . ;)

Re: 1980 tomos Bullet stops running when hot

Pushrod Fifty /

New condensers can fail fast unless they are new old stock US or European made. Best to check it when hot and cold to see if the value changes.

Re: 1980 tomos Bullet stops running when hot

Mark Scherping /

I will check the condenser. I drilled two holes in the gas cap and I could not get it started today until I took out the spark plug and cranked the motor over, then it started and ran. I drove 2 miles to a friends house and after a hour sitting it would not start until I took the spark plug out and cranked it over. On the way home it started to die and i took gas cap off and it picked up but did it again. Can a condenser cause this problem?

Re: 1980 tomos Bullet stops running when hot

♣Slew Foot♣ /

Bad plug or plug gap too low on compression.

Re: 1980 tomos Bullet stops running when hot

Mark Scherping /

I have a vapor lock problem in the carb bowl since the carb sits in cut out on top of the engine. I put heat shield around the cut out an took running shields off. Now need to wait for warm weather.

Re: 1980 tomos Bullet stops running when hot

♣Slew Foot♣ /

Condensor or seal leak when hot.

Re: 1980 tomos Bullet stops running when hot

Mark Scherping /

The heat shield did not help. to replace left seal and put external condenser.

Re: 1980 tomos Bullet stops running when hot

cary extra new plugs so you don't get stuck.

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