Carb to Air Box Boots

After cleaning and rebuilding the carbs on my 78 kz650B, I mounted the carbs to the insulators / intake manifold boots, and tightened the clamps. Then I had to install the air box boots to the air box and the carbs.

Before I started to mount the carbs, I boiled the carb to air box boots in Pine Sol for one hour. The two outer boots softened up fairly well. The two inner boots did not. Then I tried to install the carb to air box boots.

I had a VERY DIFFICULT TIME trying to do this. After messing with it for 30 minutes, I decided I had to get the boots a lot softer than they were, to be able to get everything connected. I put the boots through the air box holes, then I got my heat gun out, and I heated the boots up on the inside and the outside of the air box, and they became MUCH EASIER to work with. The heat gun made the boots very soft and pliable, much more than the Pine Sol did for me, and it was so much easier getting it all hooked together.

I had the air box bolts loosened up while doing this

I have no idea if I was reinstalling the carbs in the recommended procedure, but I would not have been able to complete this without heating the boots up the way I did.

I'm posting this in hopes that it might help someone else to get there carbs installed with the old stiff boots. I'm sorry if this suggestion / procedure, has already been posted.

Have a good weekend !!

Or you can do it the easy way and replace those 37 year old ducts with new ones that are very soft and pliable. :whistle: Ed

650ed wrote: Or you can do it the easy way and replace those 37 year old ducts with new ones that are very soft and pliable. :whistle: Ed

+1

New soft pliable ducts will fold back on themselves easily and I think they were designed that way.



Careful with that heat gun. It will work but to much will melt the rubber

Yes the heat guns can melt the rubber boots !! I had a little bit of smoke coming out of the air box on the first one I did...LOL

JR I believe you are correct in your statement about the boots folding back on themselves. I think they pretty much have to, to gain the room to remove, or install the carbs.

Purchasing new boots as suggested by 650ed is the way to go, but this bike has been setting for over 15 years, and I have no idea if it runs, how well it will run, or anything else about the condition of the internal engine components. So I am using as much of the original / existing parts as I can, until I get it running, and find out exactly what I have. Then if all goes well, I get to do a lot of work all over again, but with new parts. I love bringing these old bikes back to life !! Or at least trying to.......

These things are a real pain.I think they are one of the reasons that people switch to pod filters. I had the same problem with mine .I just wanted to get them mounted to try out the bike.I was already thinking of pods so I didnt want to fork out for new boots. Anyway,around this time ,I read about stuff called 'Wintergreen'. Very smelly ( It reminded me of the locker room in school when we played rugby!!)
So the trick is to boil the rubbers in that stuff and it rejuvinates them.You need to do it outside though as it will stink your house out for ages. I didnt have an outside so a quick search on the interweb led to the idea of soaking the rubbers in the wintergreen and wrapping them in a plastic bag for a couple of weeks.
I did that. Soaked them wrapped them up,put them away and got on with other stuff. It came time (6 months later) to get the rubbers out, I couldnt find the little buggers ! Searched high and low.No idea where they are. I ended up having to buy new ones,just to get the bike started to check it after the carb rebuild. As far as I know,my original rubbers are still downstairs somewhere.Hiding! Disolving?!

P.S.
The problem with heating them with an air gun,(apart from the danger of melting them)is that when they cool down they are more hardened and youre going to have an even worse time refitting them next time around.

Get new ducts. Z1Enterprises.com carries them. To install you might be able to push them thru the airbox. That's how I do it on my 81 650-CSR, instead of folding them.