Hi Guys My Road king classic 1996 is still playing up if i remove the carb and the carb to manifold seal put a load of grease round the inside rim of the seal refit and it runs good for say 200 miles then it starts running uneven again missing and stalling the carb petrol/air mixture is spot on.I set the tick over when it is warmed up but it revs a little high after say 5 mins. I have been having problems with the Harley for some time. Any body got any good ideas what it wrong with it ??
Thanks in advance
John

 

Have you tried new seals? Sounds like the grease is temporarily sealing the seal up until enough of it gets sucked in or gets hot and drips off. Those are probably the original seals and theyre likely hard and brittle at this point in their life. Time for new ones.

 

come on. you shouldn't have to be putting any grease around seals or gaskets of the cab to manifold. you know exactly what's wrong with it if that fixes the issue, you have bad seals where you're temporarily plugging them up with grease. replace the seals. It's a near 30 year old bike, no surprise that seals could be bad.

 

What grease, since should be using silicone grease to condition the new rubber seals (all 3), which should have the intake seals lasting about 5 years. Without silicone grease to condition the rubber seals to start with, they dry.heat rot out in about 3 years to start leaking instead.

If you are using petroleum grease on the rubber seals, it just cause the rubber to swell over time instead.

So would start with the new 3 rubber seals and even gasket from carb to manifold, and make sure that the seal plates 5/6 are not bent, since will cause problem with seals not sealing as well.
Note, make sure to put silicone grease on the manifold and plates where seals will contactthem, so seal are pulled up tightly to jugs without binding as you center it and tighten the plate bolts/nuts.

Also, double check your hoses off the carb to Voes and vacuum petcock, since hoses may be dry cracking,and engine heat is causing them to leak more at the cracks.
Again, items that should be replace about every 5 years as well.

Next,


If using am after market air filter assembly, make sure that backing support plate to motor,has been installed to hold carb in place.
Without support plate to hold carb in position, it drooping down/pulling manifold down, can cause air leaks as well.


Last one is carb itself, and could be that someone rebuilt carb, but forget to install the needed O ring needle seals/washers, and that is where you are getting an air leak if the new seals, vacuum lines, and gasket does not solve the air leak



As for finding the air leak, spray carb cleaner works very well that, since idle speed will change as the carb cleaner is sucked past the leaking area and draw into the cylinders.

 

Rather difficult for me to understand.
Looks like you have a 1996 Road King classic...I thought the road king classic was started in 1998 and was fuel injected.
Perhaps it is a Road KIng with a carb.
The rest of post is difficult to decipher.
Perhaps you mean that seals are leaking at carb to manifold or air cleaner assembly.
If unmeasured air is leaking into the motor then the bike will have an incorrect air to fuel ratio.
What does "I set the tick over when it is warmed up but it revs a little high after say 5 mins.".
Taking a wild guess that perhaps you mean the choke.

 

Yea new seals have been fitted but still the firing problem is there. Maybe they are made in China and don't do the job as one would expect.

 

Thanks for the reply but i have replaced the seals on the manifold and i have made double sure the manifold is refitted to the cylinder heads right in fact this is the second carb to manifold seal this year. I think the seal is not the right size because as you know there is on clip of any sort to clamp the seal to the carb as on other makes of motorcycle.

 

Thanks for your reply
The Road king Engine was rebuilt by a dealership trained mec 500 miles after getting it back it started to run rough and miss firing i checked all the rubber tubes from the carb etc with a vacuum pump. i replaced all the manifold seals yes i did use petroleum grease as a seal after using non at all on the seals. I replaced the v.o.e.s. still the same. So i then changed the jet as i was told it may be over fuelling then came the grease which was ok for a short time i have now used silicone sealer it starts first time but the revs build up after a short time. No i have not checked the ign timing. if you thing i should start again with new seals and silicone grease i will do as you advise. John