Cheapest Way to clean carbs

[GQROD]

I chem dipped my carbs with the throttle shafts on, and have not had any extra play in the shafts but is it possible that air could leak from the shafts and cause a high idle/lean condition?

Not to jack the thread but i was wondering if anyone had this issue?

Thanks

 

[snarl]

I like simplegreen and a bucket.

 

[Guest]

In another life I used to have to work a lot with different o-ring mfg's and types, don't get too hung up on where you get them as they're mfg'ds mostly off shore now. If you can get them try to get Parker o-rings as they are the most checked to spec IMHO. If not Parker then look for a molding seam on the o-ring, if there is any sign of one then it's cheap junk. Most times you don't see the durometer listed but if you can be sure it's under 70. If the surface is less than perfect then try as low as 45. OEM's don't shop for the best they shop the cheapest that promises to be the best.

Buna-N is a better choice over fluorocarbon (FPM) materials unless the engineer engineered the components for FPM or you know for a fact you can compensate for the variance because FPM has an uncontrollable shrink rate in the molding process. That means it is acceptable for FPM to be undersized or oversized compared to Buna-N o-rings and seals. Both are equally good in petroleum. The tolerances are opened up for them which might not work as well in your application. O-rings are to be compressed by 20% of their cross section, that is why putting an o-ring in that has a larger cross section but "fits" in place of the proper sized one rarely works. It will pucker and leak, too small of one will weep or extrude under pressure.

Are you asleep yet? Try going to O-ring and seal school for a week, it'll cure insomnia!

 

[rpickle]

I boiled my carbs after stripping the bodies completely. Used distilled water and lemon juice. Boiled each body ~ 15 minutes. I am really pleased with the results. I had a gallon of Berrymans that I used on several other occasions, this procedure worked better.

My 2 cents.

Rick

 

[Guest]

In another life I used to have to work a lot with different o-ring mfg's and types, don't get too hung up on where you get them as they're mfg'ds mostly off shore now. If you can get them try to get Parker o-rings as they are the most checked to spec IMHO. If not Parker then look for a molding seam on the o-ring, if there is any sign of one then it's cheap junk. Most times you don't see the durometer listed but if you can be sure it's under 70. If the surface is less than perfect then try as low as 45. OEM's don't shop for the best they shop the cheapest that promises to be the best.

Buna-N is a better choice over fluorocarbon (FPM) materials unless the engineer engineered the components for FPM or you know for a fact you can compensate for the variance because FPM has an uncontrollable shrink rate in the molding process. That means it is acceptable for FPM to be undersized or oversized compared to Buna-N o-rings and seals. Both are equally good in petroleum. The tolerances are opened up for them which might not work as well in your application. O-rings are to be compressed by 20% of their cross section, that is why putting an o-ring in that has a larger cross section but "fits" in place of the proper sized one rarely works. It will pucker and leak, too small of one will weep or extrude under pressure.

Are you asleep yet? Try going to O-ring and seal school for a week, it'll cure insomnia!

Your general statement that "Buna-N is a better choice over fluorocarbon (FPM) materials unless the engineer engineered the components for FPM" is simplistic to the point of being inaccurate in many circumstances. Both are families of polymers, not individual types. Rubber compounding has many variables, which have a huge effect on performance. As a rough guide, both types resist most petroleum products. Nitrile usually has better physical properties and costs less. Fluoro has much better temperature resistance, but when the temperature doesn't go out of nitrile's range, fluoro is usually not better.

Mold shrinkage on fluoro is quite predictable, if you know how to run your factory properly. I know something about this: I was Technical Director at the factory that was the world's biggest consumer of fluoroelastomers. But we also used far more nitrile than fluoro.

As far as OEMs, it all depends on the OEM. Some buy cheap and rely on what the supplier tells them. When I was in that industry, Ford required exhaustive testing and control plans. They audited our factory to be sure that we followed the plans. I audited suppliers' factories to be sure that they followed their plans. But few companies care that much, and most of those that care can't afford the extensive quality assurance program that Ford had (has?)

 

[Guest]

Your general statement that "Buna-N is a better choice over fluorocarbon (FPM) materials unless the engineer engineered the components for FPM" is simplistic to the point of being inaccurate in many circumstances. Both are families of polymers, not individual types. Rubber compounding has many variables, which have a huge effect on performance. As a rough guide, both types resist most petroleum products. Nitrile usually has better physical properties and costs less. Fluoro has much better temperature resistance, but when the temperature doesn't go out of nitrile's range, fluoro is usually not better.

Mold shrinkage on fluoro is quite predictable, if you know how to run your factory properly. I know something about this: I was Technical Director at the factory that was the world's biggest consumer of fluoroelastomers. But we also used far more nitrile than fluoro.

As far as OEMs, it all depends on the OEM. Some buy cheap and rely on what the supplier tells them. When I was in that industry, Ford required exhaustive testing and control plans. They audited our factory to be sure that we followed the plans. I audited suppliers' factories to be sure that they followed their plans. But few companies care that much, and most of those that care can't afford the extensive quality assurance program that Ford had (has?)

Let's not needlessly over-complicate the subject about low cost carb cleaning with your concerns about types versus families, it's just non-practical as the "type" I'm referring to is either common Buna-N or Viton o-rings.

Based on when these carbs were designed and built I feel my statement wasn't inaccurate, as for simplistic, in the context of what is being discussed it would be appropriate to what this post is really about which is not a full blown analysis of elastomer technology.

I merely responded with what I know when the dreaded which material is best scenario popped up. (just like oil and tires) By the way where did you get the sales numbers that 3M is out selling Dupont in fluoroelastomer's, I'd be interested in seeing that as Viton is heavily ingrained in industry by name recognition?

I have to ask, is anyone here really going to go out there and demand to know how much acrylonitrile is in the composition, what other additive compounds or single polymers are in the o-ring compound they have in there hand? Nope, just "is it good ol' commercial Buna-N and Viton" is what you're going to find. Durometer is far more important than composition of the material as long as it is readily referred to as Buna (nitrile) or Viton.

Fluorocarbon compounds have a higher than normal mold shrinkage rate, as a result molds for fluorocarbon products are often made different from molds for Nitrile based compound seals to try and compensate for this with some degree of success. Take the same size Buna-N and a Viton o-ring, mic the cross section, you'll find the Viton is on the low side of the nominal tolerance each time compared to Buna-N (it gets much worse in cup type seals).

Why I would recommend generic Buna-N o-rings over Viton in your carb rebuild? You can find them on a Sunday afternoon for one, it doesn't get hard and leak at -15?F (good for our Canuck friends to know) and since these old carbs were engineered with Buna-N nominal tolerances in mind you won't have to deal with any stretch or failure to properly compress potential when installing them.

For those considering using white vinegar or lemon juice, it won't hurt the metal as the acid concentration is too low (about 5% or less) as well as the duration of exposure. If you're paranoid you can use baking soda to neutralize any residue in one of your rinses, in fact there is a process that a now deceased fellow in Norway used to use that was just baking soda and boiling water that made his carbs look like new. I'll find the link if anyone is interested.

 

[Suzuki_Don]

I boiled my carbs after stripping the bodies completely. Used distilled water and lemon juice. Boiled each body ~ 15 minutes. I am really pleased with the results. I had a gallon of Berrymans that I used on several other occasions, this procedure worked better.

My 2 cents.

Rick

What proportions did you mix the lemon juice to water.

 

[rpickle]

Suzuki_Don,

Not very precisely, thats for sure... I used an old sauce pan and had enough water to just submerge the carb body. I added approx. 2 teaspoons of lemon juice.

Even though it is lemon juice, I boiled them out away from everything using a 2 burner camp stove. Was a bit stinky.

Rick

 

[Suzuki_Don]

Suzuki_Don,

Not very precisely, thats for sure... I used an old sauce pan and had enough water to just submerge the carb body. I added approx. 2 teaspoons of lemon juice.

Even though it is lemon juice, I boiled them out away from everything using a 2 burner camp stove. Was a bit stinky.

Rick

Thanks Rick. I will give it a try for 15 minutes or so on my CVs. Thanks again.

 

[rodm850g]

cleaning carbs

cleaning carbs

Guys,
I just went through my carbs for like the 5th or 6 th time since I have had my 79 850G. I only "dipped" them once. Didn't like that method. I have for the last few times done it differently than the dipping way that stuff is too caustic.
This time I removed the carbs, laid them out on a bench, removed all the internals that fuel and air pass through and used the "new Yamaha" carb cleaner..... The new version you mix with water the old product used gas. sortta dangerous. So into a container the main jet, pilot jet into this solution is is apparrently an organic cleaner,and its effective too. I let the parts soak for about 2-3 hours. While they were at soak,I used two cans of carb cleaner on the bodies...un assembled...... and I used the type that IS NOT environment friendly. You want a product that will cut through the old dried up gas. I have a large tub that the carbs are held over to contain the nasty....byproduct of carb cleaning. I shot that stuff through ervery orifice I could see.....I also used an air hose with attachments like needles to get air forced into the smallest places. Now the 79 doesnot have the CV type carbs the slide moves by mechanical action not vacum..
I also used a "tip cleaner" found at prolly harbour freight or a good welding shop to do a finnish cleaning of the jets....not to make them any larger than they are just to clean up any leftover varnish....
Back to the jets and the needle valves...they have cleaned up well, a nice brass/bronze color they have taken on, and the product has had a change its not clear now has a dirty look to it.
I am about ready to re-assemble my carbs now its like 3-4 o'clock and I have at least 5 hours in removing, cleaning, soaking, drying and reassembling...and re-installing my carbs....by the way did I say that I was bringing this bike out of storage ? No I didn't {I checked} yes the old GS had been put up for storage when I bought my ST1300....{this dont matter} 5 years in my back yard under a shelter with a heavy tarp over it...the stuff that came out of the tank resembled a sludge....not so much gas ....but it was full as was the crank case.....
Carbs are back together and with a new battery in place and a remote fuel resivior hooked up...choke at full... the ole boy made about three or four revolutions when it fired....to life....he's back...running fairly good without the airbox on it.....just for giggles I hoked up my carb stick after a warm up ...and 1&4 were within a mm of each other as were 2&3 were very close to each other....satisfied I put the air box back on and await time to do a paint job on my GS850GN....Thats another story for another time. Since the time I believe it was 88 or 89 when I took my carbs apart and replaced all the o-rings....haven't since...and have had sucess with current method of cleaning carbs in the past....I do use the fuel stabilizer
and whether you use Sea Foam or Sta-bil the important thing is to use something .....fuel breaks down now-a-days so quickly......its good insurance....Waiting on seat to get back from upholsterer, gonna paint him up real good and new stripes too....cant wait....cant ride my TL1000 any more bad back....but the GS will do fine...gonna show him off next year at Classic Cycle days....in Lexington....Yall take care hope everyone gets their bikes running as good as my old GS is running today.....

Rodm850g