Air Box Installation Blues

I just bought my first bike this winter ['81 xj650] with the airbox already removed. I've had the carbs rebuilt, put on and the bike runs (horrible) but I can't figure out how get this airbox in. I have read some talk of melting it down..and I thought about sawing it into pieces and maybe re-gluing it together..but I wondered if anyone here has a proven technique, perhaps even some pictures? I'd hate to sell it over an airbox!

 

IF it's like the 550, I think you can get enough clearance if you remove the front mounts of the engine and tip it forward.

NOTE, this is a GUESS, I haven't done it myself.
(I'm mounting it while my engine is out)

 

Welcome I believe member "ecologito" had this dilemma & in the end it was easier at his stage of build to pull the engine. I've also heard about heating it with a hot air gun (not melting it though)

You won't sell it over an airbox 'cos we wouldn't let you lol these bikes are too nice & you'd always have that nagging "what if" scenario playing over in your head...

Speaking of what if's, may I direct you to the links in my signature regarding disintegrating rear brakes & aged front hoses? (If I didn't tell you and you crashed I'd always wonder "what if" I had warned you)

 

I did, on the 650 you have to put the airbox in the frame before the engine goes in. I tried with a loose engine and didn't work, I had to pull it out and get the box in.

 

I got dem old can't get da airbox in the frame down home blues..cue BB King guitar

http://www.xjbikes.com/Forums/viewtopic ... art=0.html

 

its pretty easy to pull the plant.

otherwise, tip the engine forward, and use a heat gun to soften the plastic up enough to squeze it in. be PATIENT, and don't force it, you can do it!

 

I cracked mine when I pulled it out. Ordered one on eBay and after an hour and a half managed to get of back in with out cracking or removing the motor. I hax my starter, carbs, and intake manifold boots off. Do it on a nice warm day and I used a little axel grease on the spots that were hanging up, it slid right in. (Pun intended)

 

pull the plant. you can unmount + tip it foreward.... but it was still a struggle. Just pull it and give it a good cleaning while it's out.

 

Well I took the drastic measure of sawing the filter box portion off and re-attaching it inside the frame and sealing it up with epoxy. Everything seems to be back together correctly now, but it won't start. I think this is the part where I pass the job on to a real mechanic!

 

3 main components to starting a motor - fuel, spark, and compression. You compression is probably sufficient. Check the other 2. Its easy, quick and simple.

 

It isn't getting fuel, it will start when primed in each cylinder and then run until the carb bowls are empty but priming is difficult with the airbox in. Had the carbs cleaned and rebuilt by someone else. Is there some kind of accelerator pump or something that may be bad? Here's a video before the box after priming and warming it up a bit.

 

Right, is your vacuum fuel tap connected up? It should flow fuel permanently if it's on PRI and only flow fuel in ON or RES with vacuum applied...