Enough rubber?

so after spending most of the day cleaning piston bores, enrichment circuits, float bowls, and other cosmetics on the rack today I need your advice. Personally it would be great to avoid taking the rack apart to change the throttle shaft seals and o-rings. However, do these pictures show enough wear to consider changing?

This end of the rack looks fine to me


The other side is questionable.. I know I know, if I just changed them I wouldn't have any future problems but is it worth changing them now or wait til after I put it back together? ​

my own gut feeling says to leave them alone since before this tear down the carbs were operating fairly good anyhow (idle approx 1200~1300 rpms throughout the summer..) just posting to get some other opinions! thanks guys

btw, here's a few more pics of what I did today

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That's not wear. They've been ruined, probably by soaking in carburetor cleaner. Now is the time to change them.

Time to send some money to Chacal :wink:

 

I would replace them now...it's a good spot to have a vacuume leak, which will make setting the carbs almost impossible!

Kenneth

 

Absolutely. Those aren't worn, they're all done. Don't put those carbs back together with those still in there, it will never run right.

This is one of those things you simply have to do correctly, now; if you don't you will be doing it soon.

It's just a matter of how many times you want to take the carbs apart.

Sorry.

 

Agggh! that's not what I wanted to hear!!! lol oh well i suppose now is the best time to take them fully apart while I still have 3 weeks off before next semester starts.

they didn't look too bad from what I was expecting and maybe thought the plastic o-ring going on the ends would protect unwanted air from entering............. but if the general consenses from three others is to replace, then Chacal expect an order from me soon! boy this carb rebuild is getting deeper and deeper now. definitely will be posting more cause I'm predicting issues may arise but hopefully not. *fingers crossed*

think tomorrow I'll take all rubber off and soak each carb individually in lemon juice, unless others have suggestions??

 

carb cleaner isn't bad as long as it's a short soak. short enough that the seals don't get ruined. if the carbs weren't that bad to begin with you coulda just used the spray can carb cleaner.

the only time i used that soak stuff was on a rack that was CAKED with deposits. so that was a long soak. that was LONG before the internet was invented and all this wealth of knowledge cropped up.

 

Can't get better.
Can only get worse.

You're already got a good start on doing the Full Monty.
Grit your teeth and get them done.

Before you begin:
Mark the Throttle Plates.
Use a Scratch-awl and place some indelible marks on the Throttle Plates.
( 1⬆, 2⬆, 3⬆, 4⬆ )
Don't rely on just a Marking Pen.

When fitting and replacing the Throttle Plate Shaft, ... lube the New Seals and the OD's of the Shaft with Fork Oil or Brake Fluid.

No hacking.
Use Tools that FIT.
It's a good idea to replace the Throttle Plate Screws, ... anyway.

 

ya i planned to purchase them as well. Chacal, get ready for a long list from me!

Rick I've found about this already. luckily I've kept good organization but will permanantly number them somehow.

I agree. sometimes you just gotta bite the bullet and start from scratch

 

I will also echo the gang, replace them. Wrap a short length of electrical tape around the shaft end to keep the e-clip groove from damaging the seal and be sure to use a film of silicone grease when sliding the seal onto the shaft. Your bike will be much happier with the new parts!
Given the condition your seals are in, I'd also take a look at the air/fuel screw o-ring. Good bet it suffered some under the same hands.

 

is this an o-ring on the shaft that I'm going to be taking apart anyhow to replace the seals? Sorry i haven't taken it apart this morning,, but planned on purchasing all new rubber fittings for the throttle shaft anyways from chacal.
on a side note: just popped my valve cover off and got a few measurements. probably the first time checked with over 18k miles at least (speedometer didn't work with PO...go figure) Expecting a few to be tight. cheers to fitz for the wonderful write up on valve adjustment!

 

Nope - different location entirely, part of the Pilot Screw parts.(4)
You also need 6 fuel rail "O" rings,
and need to read one of the loooong how-to's on this site, like "9 Yards" or "Church of Clean".

 

are these located under a brass cap individually? I just found out where my pilot screws are if this is true... since the caps exist on my carb bodies. never knew anything was down there.. lol

hoping the o-rings are still good after I remove these caps soon. I just ordered over $200 from chacal and really wouldn't want to pay an additional $10 to ship just a few o-rings seperately :x

Time...when i do remove these, are these the screws that I always here other members saying to turn 2 to 2.5 turns out for reinstalling? many questions but this is my first true rebuild since I just broke the rack today. plan to boil each carb in either lemon juice or pinesol as well late this weekend

 

oh and I have 2 out of the 8 butterfly screws stuck! been soaked in wd40 all day but still not budging.. i read somewhere that peeling the screw heads away with a file works to remove the shaft but what about the rest of the screw still stuck in the threads once the butterfly is removed? any other suggestions besides using a file?

 

you could try a left hand 1/8 inch drill bit, might grab and come out or at least remove some metal that you don't have to file
the back side of the screw might be peened to lock it, this might be where to use the file
don't forget some heat
might be too late now but JIS screwdrivers do work better on jap screws

 

I don't recommend a drill for that operation; one slip can ruin a carb body.

Polock is right; the screws were probably peened from behind and those two just got peened enough to not come out regardless. Use a file on the backside to remove the tail ends of the screws.

WD40 is for displacing water; it's not an effective lubricant nor a very good penetrating oil.

I used to swear by PB Blaster until it (and every other bloody penetrant on the planet) failed me and I discovered Kroil: http://www.kanolabs.com/google/

 

You found 'em !
I just went thru an "early" 650 Maxim rack for my 750 Seca.
I bet you have the ultra-fine threads on your Pilot screws, and if so, you need more than 2 1/2 turns.

You also need to COMPLETELY dismantle the carb bodies:
"Seats" out, Beenie Screens either cleaned or tossed,
Enrichment plunger assemblies removed and polished,
Pilot screws out, then pick out the tiny washer and "O" ring. They don't just fall out, you gotta go get 'em.

Then, after you're done with the lemon juice, you still have to use a variety of fine wires and carb cleaner, and chase thru the TINY passages of the Pilot circuit and an additional side-hole (guitar string) and the brass enrichment tube and it's side-hole. X4. No shortcuts here!

This is the reason you hear people say they got it right the THIRD TIME !

 

okay I'm totally acceptable to using a file so the butterfly can be removed. but there's still part of the screw in the shaft and I would think it wuold be even harder to remove when its just the shaft of a teny tiny screw left. there aren't even extractors that small are there? for some reason i'm just not convinced what the next step would be after filing away the head of such a small screw like that. no worries, once they are removed the replacement hex style screws are coming from chacal

 

no more queezy butterfly nervousness! got them removed by extraction (simpler than I thought) and now getting ready to remove the brass caps off my carb bodies to take a gander at the pilot screws for the first time. these should be removed also before boiling the carbs correct? sorta feels like exploring a cave for the first time

 

well since I created this forum, figured I'll add to it now that I'm making progress. You were right TIME, all four pilot screws were around 7 to 8 full turns before coming out with needle nose. Take a look at this, seems to be "fine threads" i suppose. All that is on these screws is a o-ring (which seemed to be in great shape so I shouldn't need to place another order chacal a brass ring and the spring. Anything else I'm missing?

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The only screw that I have not removed or the two that sit between the air boots location. Do these need to be out as well? any rubber in there? plan to soak very soon!

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those can stay, just so you can blow air through them, no rubber, they come out way in the top of the float chamber

 

the soaking process is almost finished. got some carb dip from napa and at first wasn't pleased but after some tlc with a little toothbrush, the exterior crud is gone and I'm pleased.
so far the MIA count is one pilot jet. when rinsing the parts I forgot the last and smallest piece in the rinse bucket. dumped it outside in the snow

 

anybody else done this?? I'm sorta confused what the tape would prevent, since the plastic shim is placed between the seal & the e-clip

 

also, do i use loctite on the butterfly screws?

 

You put a wrap of tape on the shaft temporarily so the edges of the c-clip groove don't "bite" the edge of the seals' lips on installation. Once the seals are in place, you remove the tape.

By all means use Loctite on the butterfly screws.

 

you guys truly are wizards at this stuff. why didn't i think of that!?

o well got the throttle shafts and fuel rails with new rubber, choke pins & lever, idle screw, pilot screws reinstalled. hope to finish float bowl areas tomorrow. wish i had more time before the 50 degree weather hits friday!! work sucks!