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Carb holder leaking

5K views 27 replies 10 participants last post by  vulcanguy 
#1 ·
I have a 2002 Vulcan 750. I cleaned the carbs and replaced the float valves last year. Runs good but I can hear a vacuum leak.

I sprayed some carb cleaner around the carb boots and when I sprayed it around the rear boot, the engine picked up speed. So, it's definitely leaking.

I tried to just tighten the clamps but that did nothing.

How likely that the boots need to be replaced?

Any thoughts?
 
#2 ·
Is it possible the carbs need re-seated in the boots? They can get a groove imprinted in the rubber, and hardened, then if you seat them too deep or too shallow, it doesn't seal as well. Also, make sure the clamps sit in their imprinted grooves, same principle.
 
#3 ·
Some times you can loosen the Clamps and twist the intake boots a little till they line up better and then retighten the clamps and they will seal off.
 
#4 ·
Thanks for the info. I'll try to adjust them. I think the clamps aren't gripping the boots tightly enough. I did make sure that they are on the correct intake and were correctly installed...but they still leak. It's a little frustrating. I'll make some adjustments and see if I can't get them to seal up.
 
#5 · (Edited)
Make sure all the "protrusions" are aligned. When I re installed my carbs I put a thin coat of motor oil inside the boot opening which seemed to have helped getting the carbs in and seated. What I didn't do was get all the clamps in the proper position which made tightening the clamps difficult. Hopefully I'll never have to pull the carbs again but if I do I will definitely make sure clamps are on right. Just a few rookie mistakes that I made that I want to make others aware of. Hope this helps.
 
#6 ·
Make sure all the "protrusions" area aligned. When I re installed my carbs I put a thin coat of motor oil inside the boot opening which seemed to have helped getting the carbs in and seated. What I didn't do was get all the clamps in the proper position which made tightening the clamps difficult. Hopefully I'll never have to pull the carbs again but if I do I will definitely make sure clamps are on right. Just a few rookie mistakes that I made that I want to make others aware of. Hope this helps.
....been there....done that :smiley_th
 
#7 ·
What is TOC MCCT's?
 
#10 ·
How do I know if mine should be replaced?
 
#11 ·
ACCTs (factory automatic cam chain tensioners) tent tend to break easily allowing the cam chains to be too slack and slap around inside the engine case making a scrubbing clacking noise inside your engine as the slack chains rub inside.

There are several options to repair or replace them listed on this site. The repair I used cost about $8 in parts or you buy or you can make/order a set of tensioners that you can adjust manually about once a year.
 
#12 ·
Sorry for not getting back with this sooner. I haven't had time to tear into it.

Pulled the carbs today and found that the rear boot is torn. I may have done it when I re-installed them a few months ago. Either way, I have new boots and clamps ordered. Hopefully this will fix the issue.
 
#13 ·
While my boot wasn't torn it wasn't seated correctly. Took a while to figure it out but once I did the bike ran much better. Hopefully that's you problem too.
 
#14 ·
When I reinstalled my carbs I put a light coat of oil inside the boot. I really seemed to help in getting the carbs seated. And it's easier if you follow the procedure of leaving one boot on the engine (the front cylinder I think) and one on the other carb. And you probably already know to get all the protrusions aligned and install the clamps oriented the way the manual shows otherwise they're a real bitch to tighten. Just trying to save you from making the same mistakes I did and having to pull the carbs again. Good luck with it!
 
#15 ·
Thanks for all the input.

Got the carb boots and clamps delivered yesterday. $80 worth! But, they aren't dried out and cracked so it should run well. I'll oil them up and get them installed. I'll update once I get them on. Will try for either Sat or Mon to install them.
 
#24 ·
Got them installed today. Runs great!

Little note for anyone who is going to be pulling their carbs....the real secret IMO is to really crank up on the air box. Get that box high enough and pulling and reinstalling the carbs is actually pretty easy.
Yeah, I used two ratchet straps.

:smiley_th
 
#27 ·
OleDirtyDoc We don't need no stinkin airbox
That's my plan.... putting a KN3950 in its place.

:smiley_th
 
#28 ·
I did notice that the original carb holders were starting to show cracks. I thought about buying used ones off ebay but decided to pay extra for new ones. Glad I did because the new ones were nice and soft and pliable and I'm sure they seal better than used ones would have.

My bike only has about 14k miles on it and has been stored inside its whole life (previous owner and me) but rubber will still deteriorate.

I would seriously recommend replacing the boots when you pull your carbs if they are older than 10 years old.
 
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