Boorrrringggg Build/Rebuild/Refres&restore

[puskrat]

Okay I admit it. The past several posts, not including Wildkat's "curiosity" have been lame and not really about much. just felt I should post, even if there was no substance. Fact is, I'm not working much. Sneaking away from the day job at lunch and as I can to wrench a little and snap one or two photos, spending evenings either tending the parents or maintaining the home. I don't know how you guys with kids do it.

Any tips on how to get oversealed petcock mounting screws to spin? Something dark gray sealant/adhesive looking but thin is protruding from around the petcock base, and I think probably in the screw holes as well. Trying to disassemble the fuel valves without removing isnt working, as the lip on the tank blocks the screwdriver from the lower "inside" screws. I'm thinking about an impact, or even a hammer drill, but I don't like the idea.

Got this far....gee what a surprise, the diaphram had dissolved (well, mostly)
[IMG][/IMG]


Obstructed inside screws, preventing disassembly of the other half
[IMG][/IMG]

You can also see the goo that i believe is locking/gluing/sealing me out of removing the units altogether.

[TopCatGr58]

It's probably Yamabond or Threebond or such. Hopefully it's not J-B weld. The screws/bolts are already bunged up from the slipping phillips driver.....so grab your vicelock pliers, and get a good bite on the head of the bolt/screw and break it loose that way. THEN just replace the bolts/screws from your local hardware store.

BTW, you'll need to use either some FELT washers, or new neoprene washers under the washer head of the bolts to seal them against the petcock when reinstalling.

T.C.

[puskrat]

I got my petcocks loose! Actually the aforementioned body shop manager got tired of listening to me complain about them, so he busted them loose (with a simple screwdriver)

The more reluctant unit has not been fully disassembled yet. The one that I began to take apart whilst still attached is in pieces, crying for a rebuild or replacement. Which is the better choice, usually? I get the difference between (free) labor and expensive parts, but I've also heard some replacement valves are less than reliable/durable, so I have to wonder about repair kits as well. What's the hivemind on this?

[puskrat]

While you're thinking of how to help me with that, let me ask for your help with some other business, since that is why you visit this website, helping me.......

Fuel tank. Didnt expect to find rust, but I did. rust on the inside of the cap (chrome), but no rust at the petcock opening into the bottom of the tank. the petcock filters were fairly spotless. I think that seems to indicate the rust formed from evaporation/condensation, but wasn't in the fuel in a substantial amount. Thoughts?

[TopCatGr58]

Hey again,

Okay, some folks want to keep their machines as close to stock as possible, so the rebuild kits are the way to go. But if you've checked lately, the kits are almost as much as the cost of a NEW aftermarket petcock. As you've found that 4/5 holed rubber valve is prone to wear/damage, and not sure how much ETHANOL will accelerate that type of damage.

SO...that's why I'm going with a NEW aftermarket replacement. However, it has an NPT 3/8" type mounting, and so requires an adapter plate. They are ~$9.00 ea, which then puts the combo price back up to or more than the rebuild kit. BUT I'm getting a NEW part, and hopefully a little better engineered design/components vs. the 35+ y/o OEM design.

From what I've read/heard from folks in the know, the OEM gas tanks were NOT lined, just the presence of fuel and vapors usually prevented most rust from forming. Now, 30+ years later with ETHANOL, which is hydro/water attractive, so it can allow more water content and vapors to accumulate and so the possibility of rust forming, like what you found around the neck/filler area. You can take some stuff(Evaporust) or petroleum jelly and remove the rust. Now, there's pros and cons with regards to lining/coating the tank. YMMV, searching the threads will reveal various opinions.

T.C.

[motoman]

I got my petcocks loose! Actually the aforementioned body shop manager got tired of listening to me complain about them, so he busted them loose (with a simple screwdriver)

The more reluctant unit has not been fully disassembled yet. The one that I began to take apart whilst still attached is in pieces, crying for a rebuild or replacement. Which is the better choice, usually? I get the difference between (free) labor and expensive parts, but I've also heard some replacement valves are less than reliable/durable, so I have to wonder about repair kits as well. What's the hivemind on this?

All the screws on the bike we all would just call phillips screws are actually JIS(JapaneseIndustrialStandard). You can either get ya a JIS screwdriver or change scrws out to metric phillips scews. In my case, changed all the JIS screws out for allen head metric screws. The stainless button-head allen head metric screws look even better.

[puskrat]

If the only rust is on the cap, I'd wipe up and roll. It's the prospect of more widespread corrosion that bothers me.

I've read enough here to know sort of what I was getting into with petcocks, and the further observation that parts cost is going to be the same convinces me to just get replacements. What luck has anyone had with going to straight no-vacuum valves? I can be a little ADD, and I don't want to resurrect the gasoil demon by leaving a petcock "on".

For some reason I didn't even consider the potential use of JIS screws in and on the petcocks.

[TopCatGr58]

What luck has anyone had with going to straight no-vacuum valves? I can be a little ADD, and I don't want to resurrect the gasoil demon by leaving a petcock "on".

ALL of the specials use non-vacuum controlled petcocks. They just have the Octy vacuum control valve which many just remove anyways. IF your carbs and float needle/seats are working properly, you won't have any carb flooding/gasoil events. It's just that the petcocks turned off takes the pressure off of the float needles/seats, and removes a source for flooding IF the float/needles DO leak! An additional option is to put inline cut off valves as well, but again you have to remember to turn them to closed/off for them to work! Turning the petcocks off can become a muscle memory automatic event after a short time of doing it, like getting in the car and putting your seatbelt on first!

When parking for a long time, it's best to put it up on the centerstand, helps the float valves/needles to work easier and evenly, vs. on the side stand where the carbs are then slanted.

T.C.

[puskrat]

ALL of the specials use non-vacuum controlled petcocks. They just have the Octy vacuum control valve which many just remove anyways. IF your carbs and float needle/seats are working properly, you won't have any carb flooding/gasoil events. It's just that the petcocks turned off takes the pressure off of the float needles/seats, and removes a source for flooding IF the float/needles DO leak! An additional option is to put inline cut off valves as well, but again you have to remember to turn them to closed/off for them to work! Turning the petcocks off can become a muscle memory automatic event after a short time of doing it, like getting in the car and putting your seatbelt on first!

When parking for a long time, it's best to put it up on the centerstand, helps the float valves/needles to work easier and evenly, vs. on the side stand where the carbs are then slanted.

T.C.

Uhhhh

what's a "seat belt"?

[puskrat]

But seriously folks:

I know I have to inspect two carbs. I am lazy. Should I go ahead and disassemble all four anyway, in spite of my slothfulness?

[natemoen]

But seriously folks:

I know I have to inspect two carbs. I am lazy. Should I go ahead and disassemble all four anyway, in spite of my slothfulness?

I think that's an obvious yes.

[puskrat]

I broke the rules.

I was going for restoration. Keeping orginal configs. When the site was down and I couldnt access the tutorials, I gave up and pulled all the screws from the airbox in my frustrated attempts at removing it. Speculation is I'll not be able return it to its assembled state, and will go to individual air cleaners. As the point of this air cleaner removal is carb diag/repair, I'll just go with the resized jets to accomodate.

[DiverRay]

Airbox isn't THAT hard to re-assemble! Use a little bit of silicon seal to hold the nuts in place inside the airbox, and re-assemble. BTDT As far as carbs, DO NOT buy the K&N kits!! You should be able to replace the needle/seat assembly with Mikuni parts, set the float levels, BENCH TEST THE FLOATS, and then sync the carbs once you have the engine running again. I use a harbor freight ultrasonic cleaner for carb parts. Use PINESOL mixed 50% with water for a cleaning liquid. Don't forget the mixture screws under the seals on the later model carbs!

[puskrat]

Airbox isn't THAT hard to re-assemble! Use a little bit of silicon seal to hold the nuts in place inside the airbox, and re-assemble. BTDT As far as carbs, DO NOT buy the K&N kits!! You should be able to replace the needle/seat assembly with Mikuni parts, set the float levels, BENCH TEST THE FLOATS, and then sync the carbs once you have the engine running again. I use a harbor freight ultrasonic cleaner for carb parts. Use PINESOL mixed 50% with water for a cleaning liquid. Don't forget the mixture screws under the seals on the later model carbs!

Ray, are you referencing K&N filters or K&L carburetor parts? I was waning a bit in my commitment to Mikuni parts, but was corrected (by a Keilin rider). Not sure what all I'm going to need to fixit when i get in there. *sigh*

[DiverRay]

OOPS! It should be K&L parts. Most of the time, the needle and seat are all that you need. Everything else you should be able to clean up and re-use. Sometimes the needles are almost new, and then you don't really need much other than some time and work. Just make SURE you get ALL the jets out and clean ALL the passages!