FLT non-CV carb probs, can you help? - Harley Forum

Robq · #1 02-19-2009, 06:18 AM

Hi Guys, I'm brand-new here and have a question for an expert. I've got a 1982 FLT Tourglide (80CI) and have a bit of a problem. My bike will seem to run only on one cylinder when idling, but after a bit of a stumble it rights itself when revved and off she goes......running rich, I think though.
There seems to be a goodish amount of gas present at the mouth of the carb even with the choke off, and the acc pump squirts a good amount out. I have spark on both cyls too. However, and I'm hoping this will turn out to be the problem: when I had the carb apart I noticed that the acc pump diaphgram was porous, and allowing gas to flow THROUGH it. I have the parts on order but won't have them 'til next week (I live in Ireland - so have to get parts like this from the US).
Any other things I should look for, or any other tips on setting up this carb?
Thanks,
Robert.

shovelmike · #2 02-19-2009, 09:39 AM

Rebuilding that carb is a fairly easy job, disassemble it and soak the carb body in carb cleaner. Make sure the jets are not blocked with varnish and debris. Assure that the float has not soaked up fuel and become heavy if it is the foam type, or that it doesn't have fuel sloshing around in it if it is the hollow brass type. Reassemble and carefully adjust the float level..specifications should be in the kit. Ride safe and God bless, Sincerely: Shovelmike.

frisco-rigid · #3 02-19-2009, 07:20 PM

Hey Rob

Mike covered that well and since it is Not a CV it must be the older 38mm venturi model Keihin,, yes.???? Good carbs believe it or not..

It will give you great performance for your 80" shovel motor.. Don't get tooo crazy with the accel pump volume,, don't need tooo awful much..
You will have to be the final judge on jetting but stock jets should be close..
My old Manual says 165 main and 70 slow spd..

Have you drilled out the Idle Mixure screw housing yet.?
If not you must be careful,, then once the screw is exposed it is diff to get to on a Hot running motor but is worth the trouble..

Be sure to have your timing dead on before final carb adjustments..

Have a ball

Robq · #4 02-20-2009, 01:43 PM

Hi Shovel Mike and Frisco,
Many thanks for the info. I've taken the carb apart and cleaned it out really well, left it soak in cleaner (can't get the carb-cleaner that has the basket inside over here) and I've blown compressed air through it. I noticed whilst doing this that the accel pump diaphgram was porous, so I have one coming from the US, should have it in a day or two. Would this cause the bike to run rich? Fuel leaking through it can't be right anyway.......
The cover for the idle mixture screw has already been removed (previous owner - oh no, I hear you say the dreaded DPO!!) and you're right, it is a pain to get at on a hot motor. I'm thinking about two turns out is a good place to start, what do you think? The float is a plastic one, and the level measurement looks to be spot on.
Waiting for the carb parts now.........
Robert.

shovelmike · #5 02-20-2009, 02:11 PM

Two turns out is a good starting point for the idle mixture screw. For final adjustment of the idle mixture get the engine to full operating temperature, slowly turn the screw to the right until the idle speed drops, then turn the screw to the left until you once again notice a drop off in idle speed, then slowly turn it right again until you achieve the highest steady idle speed.
After the mixture is set you can adjust the idle stop screw to set the idle RPM

Robq · #6 02-20-2009, 02:25 PM

Thanks Mike, as soon as the parts arrive I'll have it up & running. Those are sure nice grandchildren you have. I have a little grand-daughter myself, Freya, just over a year old.
Sometimes she's scared of her bearded old grand-dad!!

shovelmike · #7 02-20-2009, 08:53 PM

Thanks, Robq, I'm proud of them. I'm glad they put up with me putting them up on the forum all the time. Enjoy little Freya, they sure grow up quickly, it doesn't seem like that long ago their father was a little fellow, he's 26 now.
Hey, glad to have you on the forum.

Robq · #8 02-27-2009, 10:18 PM

AAAAHHHH......
Definitely the Accel plugs were a bit of a problem. HD ones have a MUCH longer reach. These are the recommended Accel "high performance" upgrade too....
However, the stumbling and flat spot at speed and under load I think I have solved.... After putting the new accel pump diaphgram in (old one was porous) I thought all would be sorted, but no! upon examination today I discovered that not a squirt of gas was making it's way from the pump!! Turned out that the diaphgram was not returning to it's "parked" position, and of course, next time the throttle was opened - flat spot. Apart again, stretched the return spring a bit (26 years old....), now it's returning, but put make sure the whole thing is aligned properly or else the rod can stick and you're back to square one (ask me how I know). Anythehow (Irish expression), after making sure all was free and the nozzle pointing in the right direction, much better throttle response. Will have it out in the next few days and will give a report.
Many thanks to all, 'specially Frisco & Shovelmike.
Robert.