Mixture screws stuck/rusty + airbox woes

[bikedave99]

Well, this weekend was quite busy. I got my steering head bearing changed, and my front forks rebuilt with progressives, brake pads changed, new tires put on, as well as working on the carbs.

So, that where my problems began. I was performing the shotgun. All of my diaphrams are in good shape, but I was only able to get two of the idle mixtures screws to actually move. The other I had to work slowly back and forth until they broke free/loosened up enough to count the turns in. When I got those two out, the springs were all rusted up bad as well as the washer, and I never got the o-ring. I cleaned them up as best as I could, blew out the circuit with carb cleaner, and reinstalled. So... how do I get the others out to clean them up? I assume I should probably replace them all anyway, but how? Drill them and use an extractor? Sounds scary.

Also, since getting the bike I have not been able to get the airbox to fully seat on the carbs. It always feels like it is high centered on something and seating one side invariably pulls the other side off. All of my boots are cracked and need replacement. So, will the aging boots shrink and actually pull the carbs out of level so that the box will not seat? Seems wierd.

Sorry for being long winded but just a little frustrated.

 

[maleko89]

Dave, Morley can get those screws out. Otherwise, try PB Blaster and squirt some in there and let it sit over night. Get the right sized screwdriver and very carefully work it back and forth. You said you didn't get the o-ring out of one? Use a pick tool to remove that.

I would get new air box boots. After awhile they won't seal and you'll get unfiltered air in your engine.

 

[bikedave99]

Thanks once again Mark. I've got family in Newton, KS which is mere mile from Rose Hill, so maybe one day I'll head over there and take my carbs with me then!

Should I shoot the PB just from the exterior or also in the PAJ? Also, where would I get the new screw, springs, washer, oring, etc?

 

[maleko89]

Dave, squirt it in the screw tunnel. I wouldn't squirt it in PAJ1.

You can order the screws through Gary McCoy at Mondak Motors. You'll get 20% over cost. The listing is in VMF Links page.

 

[Jayhawk]

Thanks once again Mark. I've got family in Newton, KS which is mere mile from Rose Hill, so maybe one day I'll head over there and take my carbs with me then!

Good Lord, watch your speed as you go to Rose Hill. Ack. Bastages.

 

[MONTREALMAX]

Hello bikedave99 i am working on my max carb's as well. My airbox boots are in fairly good shape no cracking rubber still flexible, and i find the same thing....the way the box is perched on the carbs with only the boots to hold the whole assembly in place seems strange. Very difficult to get all 4 boots seated correctly. Push one side down and the other pops off, push in the center and nothing happens.....very frustrating step of the procedure.

Has anyone had issues with the airbox working itself loose from the carb intakes? I wonder if cleaning the edge of the boots with alcohol to remove some of the oily film would help them stay in place? Do not want to degrade the rubber though

 

[maleko89]

Before remounting air box I clean the inside of rubbers with a damp rag. I also clean the part of the carbs where the boots clamp to.

 

[bikedave99]

MontrealMax, sorry to hear you are having the same issues... not sure what to do with this I guess. Just doesn't ever want to sit properly or fully. I even had anothe person helping so that they could push down on one side while I tightened the other...

Maybe, I just need to clean it real good so it will grab, then find a good middle ground and get it as tight as i can.... frustrating!

 

[one2dmax]

Most of the turds I work on (even my own) have older airboxes on them and they don't like going on well. I recently had an 06 in the shop for some engine work and was amazed at how smoothly the new box went on. It's all about the airbox rubbers.

By the way, Newton is probably 35 miles or so from me!

I do have good luck getting them out but it ain't easy. I had special tools made a few years back to match my drill bits in length so I can center drill them and not have my bit go on through. I also have the very fine thread tap needed to clean the threads when I do get them out.

I don't think rusty springs and washers have ever been a problem for my use but new is nice. I keep a few sets on hand for shop bikes but I can't match the price you can get direct.

Sean

 

[bikedave99]

Sean thanks for the response, yeah I typoed on the "mere mile" bit there, was shooting for "mere miles". 35miles is close all things considered! So, are the screws resuseable when you get them out??

So, if i were to pull the carbs and come to your area sometime would you be able to pull those screws and provide a little advice? (for a fee of course) How far in advance would I need to set that up?

Too bad on the airbox though, hoping there was a solution...

 

[Buster Hymen]

MontrealMax, sorry to hear you are having the same issues... not sure what to do with this I guess. Just doesn't ever want to sit properly or fully. I even had anothe person helping so that they could push down on one side while I tightened the other...

Maybe, I just need to clean it real good so it will grab, then find a good middle ground and get it as tight as i can.... frustrating!

When mine got to that point, the only thing that fixed it was getting new boots for the air box. I ended up buying new boots for everything on the intake.

 

[bikedave99]

When mine got to that point, the only thing that fixed it was getting new boots for the air box. I ended up buying new boots for everything on the intake.

Where did you pick those up Buster? It would be the best solution for me in the end because i probably have air leaks all through the boots!

 

[Akatora]

Hello, bikedave

I had same problem with one carb. You can try following:
- spray some rust remover into the screw / thread
- let it be for a while
- give it (mixture screw) a couple of shots of pressurized air, as high pressure as you have
- then pick up exactly suitable size of a screwdriver and carefully try to turn them out

This method worked for me. Eventually the head of that one screw was f??k?d up, and I gave it some first aid by soldering the damaged head full of solder metal, and then grinding there a new contact surface suitable for a screwdriver. I will replace the screw during the winter. Actually, I already put the machine to have a "winter sleep".

Regards,

AT

 

[MONTREALMAX]

Akatora winter sleep already??? I don't want to even think about that!! I try to ride until the end of October up here.....

you have to have balls that clank to ride into November in Montreal
actually clank and shatter !!!

 

[one2dmax]

It does take a bit of time to get them out but depending on the day and the time you have we can get it done. If you want to strip down the carb bodies to the bare body and ship them to me I can remove the screw and hot tank them clean (do all four for you). I won't charge you a fortune if you take them apart and put them together.

If you did it while you were here it takes 2-4 hours to sonic them clean depending on how dirty they are. Of course I do have spare carb bodies I can sell you too if I am unsuccesful. I think I have maybe not been able to save 1 or 2 but that's because of previous owners attempts to remove them (do what you want but don't drill the dang thing since it make it harder for me to stay centered when I drill them.

The screws will not be re-useable but the springs and other stuff is. I do have a few used screws around but also have the new ones too.

Sean

 

[MONTREALMAX]

LOOKED OVER THE BIKE WITH A FINE TOOTH COMB AGAIN.

DECIDED TO BE SAFE REPLACED ALL OF THE INTAKE BOOTS (AIR FILTER AND CARB TO VBOOST) COST ABOUT 190$ CND FUNDS OEM YAMAHA.....
I WILL TELL THE KIDS THAT SANTA HAD LISTERIA THIS YEAR WHEN THEY FIND THE TREE IS BARE UNDERNEATH

TWO OF THE CARB BOOTS HAD SLIGHT HAIRLINE CRACKING ON THE OUTSIDE BUT WERE NOT COMPLETELY SPLIT, FAR FROM IT. BUT I FIGURE WHY TAKE A CHANCE AND HAVE TO TEAR IT APART NEXT YEAR WHEN THEY DO LET GO

JUST A REMINDER THAT WHEN YOU TIGHTEN THE JET BLOCK MAKE SURE TO DOUBLE CHECK THE TIGHTNESS OF THE NEEDLE JET AS THIS WILL LOOSEN AS YOU TIGHTEN JET BLOCK AGAINST THE NEW GASKET

ONE OF THE AIR MIXTURE SCREWS O-RING'S IS NOW TOAST FROM ALL THE ADJUSTING....YAMAHA WILL ONLY SELL YOU THE COMPLETE SCREW KIT.....

FUNNY THING IS... I ALWAYS FEEL LIKE I AM GETTING THE COMPLETE SCREW ONCE I WALK THROUGH THE DOOR OF THE DEALER :eusa_dance:

 

[richwrench]

How critical is the pilot screw o-ring anyway ? I have one missing on carb #3 & it makes no difference in the idle when I plug the pilot screw hole with my finger. Bike runs great ! Note: I did buy 4 new o-rings from CycleRecyle & I intend to replace all of them anyway , but I don't think it will make much difference. Maybe it has to do with my idle being at 1250 rpm instead of 1000 ? I gues I'll find out after I replace them. Anybody ever leave those o-rings out & see how it runs ?

 

[Akatora]

Hello,

O-rings are standard stuff. It is not necessary to use the original one - especially if you have to purchase the whole set. Pick up similar o-ring from another screw and they can sell you it based on the dimensions. Costs probably something like 10 cents.

Regards,

AT

 

[one2dmax]

I am about out of the o-rings I have on hand and need to order more. You are right that Yamaha does not offer them separetly but that isn't too much a problem with the aftermarket making every size o-ring known to man.

Sean

 

[Buster Hymen]

Where did you pick those up Buster? It would be the best solution for me in the end because i probably have air leaks all through the boots!

I bought them from where Gary McCoy used to work. If you contact him at his new place ( look in VMF Links), he can get you the parts (with the usual discount!) :banana: