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General Category => Maintenance => Topic started by: pict on August 07, 2021, 10:41:10 AM

Title: How to re-install carb bank and airbox easily?
Post by: pict on August 07, 2021, 10:41:10 AM
Trying to reinstall the carbs and airbox (1986 FJ1200) but having issues. I have the subframe top bolts removed and the subframe swung down a little. Soaped the inlet boots and installed the carbs into these easily. Inserted the airbox (with side panel for filter access removed) behind the carbs. Found that the airbox boots were sitting about 1/2" above the carb mouths. Raised the subframe and put the bolts back in to hold it. This improved the lineup but boots still sitting 1/4" or so. I can almost get the No1 cylinder boot slipped on but the others want to fold back their boots on the bottom edge.

Is there a trick to this? Do I try and get the carbs into the airbox boots first and then insert into the inlet boots? I don't think there is anything under the airbox that is stopping it going down a little further - the airbox drain tube is dropped down the back of the engine. The ignition vacuum line from No2 routes under the airbox but as far as I can see the channel in the side of the airbox is bottoming out on the top rail of the subframe.

Any ideas how to get it all to line up and to stop the bottoms of the airbox boots folding inward? Thanks.
Title: Re: How to re-install carb bank and airbox easily?
Post by: fj1289 on August 07, 2021, 11:17:27 AM
I "think" Waiex191 invented a simple little tool to make this easier.  Was discussed within the past year I think.  Don't know if it made it into the carb files or not  :pardon:
Title: Re: How to re-install carb bank and airbox easily?
Post by: Old Rider on August 07, 2021, 11:52:50 AM
Quote from: fj1289 on August 07, 2021, 11:17:27 AM
I "think" Waiex191 invented a simple little tool to make this easier.  Was discussed within the past year I think.  Don't know if it made it into the carb files or not  :pardon:

Wasn't that Milletant ?? using a steelwire from a cloth hanger bent into shape ??
You can also use the tip Pat came with heating the rubbers up with heatgun carfully ... sometimes the old rubberboots on the backside of the airbox is very crimpled and teared   you also can lift the carbs up and down a little even if they are inserted in the inntake rubbers ,but it helps allot with new soft inntakerubbers.And engine breather hose going into airbox is much easier to connect when it is fresh and soft. That is my experience RPM sells them Last year I bought a new used airbox on eBay that had very good rubber on the backside that made the job much easier
Also pay attention when you torque the 3 small bolts holding the airbox if you use too much force they suddenly just spins around and then they are hard to get out again  :dash2: :biggrin:
Title: Re: How to re-install carb bank and airbox easily?
Post by: Waiex191 on August 07, 2021, 12:17:54 PM
This would be Ryan's miracle tool, invented by Dean's (Milletant's) son.
Quote from: Millietant on June 30, 2020, 01:40:17 PM
This is my "special tool" which makes getting the Carb rubbers on and in place pretty easy - very technical fabrication using specialist materials..........a metal coat hanger, a pair of pliers and a bench grinder (just to put a point on the business end, on the right in the photo).

It's about 18" long in total. The short right-angled end with the point is used to slide between the carb body and the rubber boot, then twist and lever the boot over the carb body. I was struggling with screwdrivers and levers and lots of grunting and pushing, and my youngest who was helping me just said...."dad, why not make a little tool out of a coat hanger instead of fiddling with screwdrivers".........sometimes a fresh mind sees the simple/obvious solution  :sarcastic:

(http://fjowners.com/gallery/11/6213_30_06_20_12_30_41.jpeg)

Here is my version:
Quote from: Waiex191 on July 02, 2020, 11:59:46 PM
I've gotten through a good bit of my list.  One bit of heartbreak - the vent line for the airbox wasn't routed properly, and was pinched between the airbox and the frame.  I had to take it back off again.  Life was bleak.  But then I made a copy of Ryan's miracle tool, except I used welding rod as that was what I had.  I didn't think it would work as well as it did.
(http://fjowners.com/gallery/11/6694_02_07_20_10_42_14_0.jpeg)

It also helps if you screw up a lot, as repeated R&R of the carbs tends to sharpen up that skill.
Title: Re: How to re-install carb bank and airbox easily?
Post by: pict on August 07, 2021, 01:51:05 PM
Thanks for the suggestions. Have a coat hanger and will give it another go.
Title: Re: How to re-install carb bank and airbox easily?
Post by: Pat Conlon on August 07, 2021, 03:11:55 PM
1) Make sure the air box to carb boots are pointed in the correct position. See the little arrow and dot indicators on the boots and air box, rotate the boot to line up the arrow between the 2 dots.
2) The hardest thing about the air box installation (I recall) was reconnecting the crankcase vent hose.
What I did was to remove the plastic snap in hose fitting on the air box and replace it with one of these:

(https://cdn.mscdirect.com/global/images/ProductImages/5361047-24.jpg)

I put the connector on the crankcase vent hose then, after the air box was in place, I poked the threaded end into the air box, then reached into the interior of the air box and threaded on the nut and washer, finger tight.

Cheers

Pat

Title: Re: How to re-install carb bank and airbox easily?
Post by: Millietant on August 07, 2021, 04:47:11 PM
Quote from: pict on August 07, 2021, 01:51:05 PM
Thanks for the suggestions. Have a coat hanger and will give it another go.

Hope you have as much success as Waiex and me  :good2:

I can get my carbs on and off easily now in a matter of minutes.... having done it a lot of times. My son's "Tool"  idea really helps manoeuvre the rubbers over the carb mouths.

That, dropping the subframe and disconnecting the throttle cables at the splitter box are the 3 things that turned carb installation from a time consuming, knuckle-skinning, chore into a simple straightforward task.
Title: Re: How to re-install carb bank and airbox easily?
Post by: pict on August 13, 2021, 04:56:24 PM
Well I got there in the end reinstalling the airbox. Thanks everyone. Tried the bent wire tool but as the boots were always folding in on the bottom edge and I couldn't figure out access or technique to lever them on. What eventually worked was to loosen the engine side boots and lever up the carb bank with a large screwdriver against the frame until alignment was perfect then wiggled them on. Three pairs of hands would have helped.
Title: Re: How to re-install carb bank and airbox easily?
Post by: JPaganel on August 13, 2021, 05:39:21 PM
You generally have problems if the boots are old and stiff.

Otherwise, it really isn't that big a deal.

Also - as you figured out, you don't tighten stuff until everything is in place.
Title: Re: How to re-install carb bank and airbox easily?
Post by: rdbilly on May 12, 2022, 04:39:41 PM
I found the best way is to pull the carbs from the inlets and connect the back of the carbs to the airbox rubbers with all the airbox bolts removed. Then tighten down the clamps on the airbox rubbers. With plenty of lube the carbs should slide back into the inlets. Tighten the inlet clamps. You might have to jemmy the air box a little to align the bolt holes.