Suddenly 3 and 4 not working

[Getty]

Havn't been around here much since I've been riding all the time. Well, she just started acting up on me. Last weekend I finished a trip through the Rockies. Good thing this didn't happen durring the trip. I synced the carbs just before going on the trip. She ran great.

Took her to work today(Ran Fine) and the last 5,000 miles since purchase. Fired her up to go home. Made it to the gate and she died on me. Noticed one of the fuel lines on the left side was kinked. Un-kinked it and off I go(Must have been like that since the sync. Then she died on me on I-70... Let sit, looked at fuses. Started up. Drove a few miles then she died again. Let sit a few minutes... Started up. This happened the whole way home. Afte she started she ran well for a few minutes then slowly dies.

When I got home I sprayed the pipes. 1 and 2 HOT SIZZLE. 3 and 4 hardly any Sizzle. Checked the fuel flow. It was good on both sides. I rebuilt the petcocks a few months ago. Cleaned the carbs when I first got her. Not sure what the problem is. But, Im sure you guys will have a good idea as to what the problem is.

[TopCatGr58]

Hey Getty,

3-4 share the fuel flow, not electrical/ignition, so....it looks like a possible trip back into the carbs. You say you have good fuel flow from the petcocks to the carbs, so either the "T" going to them is clogged, or crud gotten into the filter screen on the float needle seat. Forgot to check what model/year you have, but if standard, be sure vacuum hoses to petcocks intact, not leaking, loose. If special, doubtful if Octy at fault cause it serves all carbs, would cause problems to ALL carbs if not flowing, but again, fuel lines can get clogged.
T.C.

[Getty]

The Story Thickens

I took your advice and had a look at the carbs.

After carb removal. I noticed the old rubber valve gasket (petcock) particles were clogging the fuel carb input. Under the float seats were an accumulation of rubber. Blew out with compressed air. Synced carbs (Not much if Any)...Looked good, but you guys are going to say "Clean em Again" I duck for cover.

Went for a ride... 0-85... Fast SMOOTH...

Then she totally lost power in 5th gear 40 mph. Dropped to 4th gear. Smooooth... Gas station... Smooth as silk for the 15 mile test ride (all RPM all speed).

Not sure about this loosing power thing. Felt just like before with the sudden power loss. The she just purrs like a kitten.

Accept when I’m running high RPM (down Shifting) then stop. She will idol very high. Give some throttle and RPM lowers. From previous posts, I’m thinking its a vacuum leak???? But, that doesn’t explain the sudden loss of power then perking right up to the very beast she really is. There just might be three problems here.

1. Rubber in carbs from the old petcock valve gasket. COMPLETE

2. Vacuum Leak? (possibly the rubber caps carb ports) Not sure where else to look.

3. Electrical? any ideas to the power loss?

Thanks TopCat! I feel like I can ride another day.

[boyat68]

Getty:

Sounds as if you have the wrong type of fuel hoses, are you sure that you have fuel hose instead of vacuum hoses? If particles are congregating in your carbs, then it seems as if your hoses are coming apart.

[Getty]

Im very sure... When I removed the old valve gaskets out of the petcocks they were rotting away. There were big chunks missing from the old gaskets. Im thinking that was a big reason why the petcocks leaked after 1,500 miles of bringin her back to life. The rubber chunks I found looked just like thos old valve gaskets.

The gas lines all look to be in good condition. Havn't done enything with them. Will keep it in mind for the next time I get into the carbs. There should not be anything under the float seats next time.

[boyat68]

Getty:

One other thought, check to see if you have the inlet screens on the bottom of your valve seat. If those are missing it will allow particles, also check to see if they are blocked up with particles as that will prevent fuel from filling the bowl.

[TopCatGr58]

Hey Getty,

Hanging idle often means out of synch, but could be vacuum leak??

Okay, cleaned the particles from under the float needle seat and screens, but did you pull the pilot jets? They have very fine holes that could get partially clogged with smaller rubber particles/debris?

As for low power in 5th at 40mph? I don't get out of 2nd gear at 40mph!! You downshifted and it was okay, perhaps you were down in the lugging zone??
T.C.

[planedick]

Sounds like

The gas cap may have a plugged vent. Try running with cap loose.