Carb-airbox boots won't stay on?

[longranger44]

Maybe this has been covered extensively here but thought I'd post. I noticed that the rubber boots that attach the air box to the rear of the carbs on my 82 gs750 wouldn't seat fully just from pushing the box forward. I could push them forward and try to tighten the clamps at the same time but they would inevitably slip back off. Took the air box out and noticed that the boots were not even, the two in the middle of the air box in particular were caved in. Detached them from the air box and it became obvious the plastic of air box was warped from age or heat or whatever.

So my solution was--stack some sockets/washers up inside the air box to spread the plastic until the holes are even and then heat up that wall of the air box with a heat gun to re-form the plastic. Here's a pic to illustrate what I did, figured I'd post it in case it might help someone out who has the same issue.

[chuck hahn]

Yes the plastic seems to dish in over time. Ive done this to every plastic box ive ever dealt with . Outer ones seat normally but two inside ones wont.

[longranger44]

Yes the plastic seems to dish in over time. Ive done this to every plastic box ive ever dealt with . Outer ones seat normally but two inside ones wont.

Yep exactly. It's really not a great design because there is zero support in the middle of this large plastic box. A couple of abutments in the middle would have prevented that, surprised the Japs didn't think of that they seem to think of everything else.

[Sandy]

Yep exactly. It's really not a great design because there is zero support in the middle of this large plastic box. A couple of abutments in the middle would have prevented that, surprised the Japs didn't think of that they seem to think of everything else.

Thanks for tip. My GS1000 airbox fits a bit funky so this winter I'll check that out. As for the Japs not thinking about it I don't I think they thought we be riding these things 40-45 years
later. LOL

[longranger44]

Thanks for tip. My GS1000 airbox fits a bit funky so this winter I'll check that out. As for the Japs not thinking about it I don't I think they thought we be riding these things 40-45 years
later. LOL

True lol. If they didn't want that then they shouldn't have made them so damn well!
another little tip, I used my heat gun on its hottest setting but make sure to keep it moving so it doesn't heat up any one area too much, if it starts to turn shiny it's too hot.

[chuck hahn]

And use a hammer handle or big screwdriver grip to push the wall forward from the filter side. Hold till it cools sufficiently or dunk it in a bucket of water to reset the shape

[jdub6092]

I just got done doing this for the third time. The first time took nearly all day and I still may have had a leak.

Just recently did rounds two and three and it went fairly quick, so I'll share what worked for me.
Obviously, you need to remove the battery holder, then loosely attach the screws that hold the filter cage mounting brackets to the air manifold/plenum.
Next make sure that the dots on the outer boots are adjacent to the dots on the manifold.
On my manifold, one of the center boots has some play to help alignment to the carb. See if yours will move left/right. Maybe stuck?

I then put a bit of dielectric grease (what i had available) on the inside/outside edges of both the carb and manifold boots.

Next, insert the carburetor all the way in at the cylinder head boots. You should now have some space between the manifold boots and the carb.

Tilt the carbs slightly down and the manifold slightly up to make initial contact. Adjust the one center boot to line up

Next use a heat gun the soften up the boots. You won't have 360 access, but hit all sides on the top and whatever you can on the bottom.

Finally start the back and forth movement of carbs and manifold until they are inserted. I only had to rock the manifold up and push forward. Getting the initial alignment is the key.

This is just the method I came up with and it worked for me. Best of luck!

[longranger44]

I just got done doing this for the third time. The first time took nearly all day and I still may have had a leak.

Just recently did rounds two and three and it went fairly quick, so I'll share what worked for me.
Obviously, you need to remove the battery holder, then loosely attach the screws that hold the filter cage mounting brackets to the air manifold/plenum.
Next make sure that the dots on the outer boots are adjacent to the dots on the manifold.
On my manifold, one of the center boots has some play to help alignment to the carb. See if yours will move left/right. Maybe stuck?

I then put a bit of dielectric grease (what i had available) on the inside/outside edges of both the carb and manifold boots.

Next, insert the carburetor all the way in at the cylinder head boots. You should now have some space between the manifold boots and the carb.

Tilt the carbs slightly down and the manifold slightly up to make initial contact. Adjust the one center boot to line up

Next use a heat gun the soften up the boots. You won't have 360 access, but hit all sides on the top and whatever you can on the bottom.

Finally start the back and forth movement of carbs and manifold until they are inserted. I only had to rock the manifold up and push forward. Getting the initial alignment is the key.

This is just the method I came up with and it worked for me. Best of luck!

If the airbox is warped like mine was there's no point in even trying to install the boots, you'll just drive yourself crazy and even if you get them all on they'll eventually pull off again. Fix the airbox like I outlined in the 1st post and everything will fit together easy like it should

[Nessism]

The heating trick sounds like a good one. The kitchen oven could be used, although it may well stink up the house...

I'm NOT a fan of using grease inside the boots where they seal to the carbs. That will just make them want to slip back out.

What I do is to position the airbox in the frame, but don't bolt it down. Then get the carbs in place, between the head boots and carb boots. Next, push the airbox forward, onto the back of the carbs, and tighten down the clamps. Last step, push the carbs with airbox, forward, into the head boots. Before tightening the clamps, bolt the airbox to the frame, holding everything in place.