510 sputtering at 2500 rpm

[DATN510]

Hello Ratsuners,

My friend has a problem with his L18, she sputters around 2500 RPM. She has a new engine build and was running fine a few weeks ago, 

she has a new alternator, and a gear reduction starter, single points, new plugs. She idles fine and revs fine. when ii drove her. she started to sputter rapidly.

She has dual SU carbs,

Any help would be great?

Thank you!

Mike 

[banzai510(hainz)]

was the coil changed? does this have a ballast resisitor. If that was all good and raqn fro awhile I would look at the SUs but I dont know this carbs.

 

condensor on distributor.

 

I think this is a EZ fix if not the carbs

[Doctor510]

Check:

 

1    point gap

 

2    Carb float levels

 

3    Oil level in the carb dash pots, (I use ATF)

 

If you do not understand the SU carbs, search and learn

[datzenmike]

Try a new fuel filter. If it craps out under load it may be running short of gas.

[DATN510]

Hey! 

Thanks for the replies. we have done all these, new filter, new fuel pump, points, condensers, checked float bowl level when bogged down, new coil, plugs, wires. oil level on pots.We still need to change or check ballast, and recheck float levels.

im sure its something simple, but haven't figured it out yet. we'll look at more on monday.

Any other suggestions would be great! Thank you all.

Mike

[Dolomite]

Make sure the vents on the float bowls are clear and any attached tubing isn't obstructed. I had issues like you are describing, I doubt this is your problem but if so, it's a free fix. I went from sputtering to pulling hard to 6k rpm when I removed the messed up vent tubing.

[DISLEXICDIME]

Check alternator voltage Rev the motor when you do it

[banzai510(hainz)]

chokes stuck ON????????

[KoHeartsGPA]

You might want to take a look at the plugs, what color are they?, might be running lean, timing checking is important also.