Page 2 of 3

gas leak

Posted: Mon Mar 26, 2007 7:38 pm
by rooster4321
I have gas in the plenum and leaking through the gasket onto the motor . Why is this leaking? rooster.

Re: carb abc and white plastic thingy

Posted: Sat May 10, 2008 1:18 am
by heraldhamster
randakk wrote:...Alos, carb tops / CV slides are factory matched to very close tolerances, so ideally if replacement is necessary, you should replace with a matched set for best results.
found a problem today. broken little white doobie cap thingie... what the!!

so my dumb question of the week would be, when Randakk says "matched set" he means each individual cap & CV slide 4 to a rack... not that you have to replace all four caps & CV slides on the rack 'cause they're a matched set?!? right?

that make any sense?

okay, two dumb questions this week... is it at all possible for the CV slide to come up fast & hard enough to break the little white doobie cap thingie??

I hope I haven't gummed up any works, I replaced only one cap & slide this afternoon. runs better than this morning, I know that. would've gotten to it next week anyway, got a rebuild kit & DVD on it's way. thanks Randakk!!

that is all.

Posted: Sat May 10, 2008 4:48 am
by Alley Kat
The matching would refer to the upper metal body and the slide that moves inside it, because they'll have worn in nicely together over the years. They should be kept together.

The plastic cap is just a cap and isn't fussed who it partners with, so long as it isn't cracked/leaky. Heat and light / UV embrittlement would likely be what sees off the plastic, possibly helped a little by high-frequency vibes from the running engine.

Posted: Sat May 10, 2008 8:54 am
by ritalz
HH
I read once that a US quarter is the same size as the white plastic cap and if you can locate four of them with the same year as your bike...
Mine are very brittle and will be replaced when I get the time to tak things apart. Maybe not during riding season.

Posted: Sat May 10, 2008 9:44 am
by Whiskerfish
Just make sure that little hole stays open where the air goes to the top to create the vacuum.

Posted: Sat May 10, 2008 10:44 am
by KarlK
Very informative.
So does anyone know why they chose to make them out of plastic instead of the same metal as the rest of the cap?

Were you supposed to be able to see through it when it was new or something?

Posted: Sat May 10, 2008 8:21 pm
by heraldhamster
ritalz wrote:HH
I read once that a US quarter is the same size as the white plastic cap and if you can locate four of them with the same year as your bike...
Mine are very brittle and will be replaced when I get the time to tak things apart. Maybe not during riding season.
good one Al. I am replacing them on the spare rack I'm rebuilding next weekend. either with '78 quarters OR aluminum arcade tokens.
alleykat wrote:The matching would refer to the upper metal body and the slide that moves inside it, because they'll have worn in nicely together over the years.
that's what I was hoping for. so I did okay... thanks!

Posted: Sun May 11, 2008 7:14 pm
by Sidecar Bob
The cap on one of my carbs was cracked. I found some washers that are a perfect fit around the raised part of the plastic doobie caps and the OD is the same as the raised part of the vacuum chambers. I epoxied them on and epoxied Canadian 2002 nickles on, beaver side up over the holes in the washers.

I used 2002 nickles because that was the Queen's 30th anniversary so they have the date on the side with her pic instead of under the beaver like most years.

Since I was painting the carbs anyway, I found some sticky dots the size of nickles and masked them before painting and now I have shiny gray carbs with really shiny, dateless nickles on their tops.

Posted: Sun May 11, 2008 7:48 pm
by Cookie
I imagine popping that little cap in saved 1.6 seconds on the Kehin production line. They weren't worried about 30 years later.

Posted: Sun May 11, 2008 8:45 pm
by Roady
Why is this thread not in Octane's Corner?

Excellent stuff there, so clear.

Posted: Sun May 11, 2008 9:11 pm
by heraldhamster
ritalz wrote:HH
I read once that a US quarter is the same size as the white plastic cap and if you can locate four of them with the same year as your bike...
well, I did some tinkering around yesterday and found my white caps must be different than others. my U.S. quarters won't cover all of the white plastic. so I'm going with the arcade tokens. they're very, very shiny, lightweight & they say "TILT" (as in pinball machine) on them.

Posted: Sun May 11, 2008 10:51 pm
by Sidecar Bob
I think quarters might fit in the opening if you dug all of the white plastic out, but then the pistons would hit the quarters.

Herald: See if you can find some nice 19mm washers like I used and put the tokens on top of them.

I thought about gluing $2 coins on mine as they are just about the same diameter as the washers, but I'm just too cheap.... After spending about $10 for new hardware (screws & lockwashers for the float bowls, screws for the vacuum gauge ports, screws and washers for the stays and the 19mm washers) and $8.16 for 4 aluminum washers for the vacuum gauge port screws from the Honda dealer, another $8 to put those dumb looking coins with the brass centres on top was just too much. The nickels are bigger then the holes in the washers and will probably stay shiny longer too.

Posted: Sun May 11, 2008 11:31 pm
by Cookie
If anybody should have tilt on them it should be you. I went to Ironman with a buddy after a couple of drinks last night and we both thought it was a kick.

Posted: Tue May 13, 2008 7:13 pm
by gladmaker
I coated mine with JB Weld last summer. It's holding good. Much easier than putting a washer or coin in it.

Posted: Wed May 14, 2008 12:18 am
by Sidecar Bob
Here is a pic of my carbs with the washers & nickles on and the caps painted.
I could have just added a coating of epoxy, but I figured the washers epoxied on top of the doobie caps and the nickles epoxied over the holes in the washers would be stronger.
The washers are 19mm metric washers from Canadian Tire. They fit snugly around the bumps on the doobie caps and are almost exactly the same OD as the bosses on the carb caps.

Image