L20b won't idle

[FireFighterZach]

Here is the story

Me and some buddies took a trip from portland to Seattle. The 71 510 goon was going along just fine when it jerked a little but, thinking I hit a rut in the road I kept driving. 3 mins later it happened again, but this time it kept happening, so I taught I better pull over and check it out. As I was heading for the ramp there was a HUGE loss in power.

As I hit the off ramp I put the clutch in and it died, I coasted to a gas station and tried to start it.

I found that it won't idle, I can get it to run if I give it gas.

After playing with the carb for a bit we decided to pop the valve cover off, when I noticed that on intake valve for cylinder 1 and 3 there was a dent on the side of the top hat of the valve spring.

 

I towed it home and haven't touched it yet, but I will have some cash flow as of the 7th any ideas?

[I'm BLUE]

Make sure your fuel filter isn't clogged.

Carb jets .. clean them.

Check fuel pump volume/and check for gas in oil if a mechanical pump.

 

Test your ignition stuff (multiple-meter/test light) and make sure you didn't drown anything in water such as from highway or interstate areas/ruts.

 

Check timing chain stretch.

A compression test at least.

Leak down test is best if need be.

[bilzbobaggins]

Dont know what carb you have, but maybe a vac leak from weber adapter?   Happened to me from some guy not using thread locker on the studs :blush:

 

Good luck

 

Jeff

[banzai510(hainz)]

when I noticed that on intake valve for cylinder 1 and 3 there was a dent on the side of the top hat of the valve spring.

got photos?????

 

maybe a lash pad fell out??????????

 

no idle is a idle jet or mixture off.

 

soewmtime pulling the manual choke will keep it running enough to get home

[datzenmike]

Probably dirt in the carb. Replace fuel filter and cut the old one open. It is dirty? has it come apart and let dirt go to the carb? Even if the answers are no, changing it is cheap easy and will do no harm.

 

Possible dirt in the idle circuit:

Unscrew the idle mixture screw. Count the turns needed so it can be replaced in the same relative position.... don't drop and loose the spring around it.

 

Now get a can of carb or brake cleaner, the one with the red straw on it. Stick the straw in the idle mixture screw hole and blast it out. Replace screw and see if that has got it. Don't get that shit in your eyes.