nklr: 82 honda 750 carb question

[RobertWichert]

Well, it's not a curse, it's a class! It "should" be possible to remove ALL the carburetors without disturbing the linkage too much. This is where I would start, not one at a time. Try to find where the throttle linkage connects and disconnect that and go from there. I have NEVER working on a 750 Nighthawk, so my suggestion is merely what I would do, not borne out of experience. You are probably lucky you don't have a gas tank. That would just be in the way at this point. What type and style / model number are the carbs? There could very well be rebuild kits available which are just a pile of o-rings, gaskets, and like that. Very handy. They come with instructions, usually. Robert Wichert P.Eng. LEED AP +1 916 966 9060 FAX +1 916 966 9068 ===============================================

On 12/26/2011 7:44 AM, Jeff Saline wrote: > > On Mon, 26 Dec 2011 01:15:17 -0000 "Kevin" > > writes: > > Looking for some help with a project bike. My 18-yr-old son just > > bought an '82 Honda 750 Nighthawk for $100. It had no seat, tank or > > key. Seller said it had been sitting for 5 years, and was running > > when put away. > > > > We installed a new battery, poured a tablespoon of oil in each spark > > plug hole, installed new plugs, changed the oil and removed the four > > carbs with the intention of cleaning them. We cleaned one as best > > we could without separating it from the others; we were daunted by > > the intricate linkages and plumbing. We thought, what the heck, > > let's just see if it will start. We re-installed the carbs, rigged > > up a temporary plastic gas tank, and what do you know! It > > eventually started, producing an impressive cloud of smoke. > > > > We let it run for about 20 minutes. The smoke lessened, but it > > won't idle below 3,000 rpms and there's a lot of gas draining out > > the carb drain tubes, including the one we cleaned. > > > > My son has ordered a gas tank, but it doesn't come with a petcock. > > I don't know if this bike has a vacuum diaphragm on the petcock > > similar to the KLR. Could the fuel draining from the carbs be a > > side-effect of our temporary tank, which has no petcock at all? If > > not, any ideas where the problems might lie? What's causing the > > high idle? > > > > I'm no carb genius; I finally resolved some long-standing carb > > problems on my KLR by buying an eBay carb. I appreciate any > > wisdom you might offer. I have not yet found a Honda 750 forum that > > compares in knowledge or helpfulness to you guys here. I've had a > > great time working on this bike with my son. Thanks in advance for > > your help. > <><><><><><><> > <><><><><><><> > > Kevin, > > Charlie Y covered the flooding issue with it probably being a stuck float > or floats or needle valve(s). > > I'm gonna guess with the flooding issue the engine won't idle because > it's getting too much fuel. You are having to hold the throttle open to > allow enough air into the combustion chamber just to keep a combustible > mixture. > > I too will suggest you remove the float bowls and inspect and clean the > floats and needle valves. While you are in that area it's probably worth > shooting some carb cleaner through the jets. > > Be careful of o-rings. They will probably be hard and brittle. If you > can avoid messing with them you might keep from creating a new issue. > > If there is no uncovered vacuum nipple on the carb(s) between the > throttle plate and the engine you probably don't have a vacuum operated > petcock. If you do have an uncovered vacuum nipple that could be for a > vacuum operated petcock and also could be the reason the engine won't run > below 3,000 rpm. > > Sometimes a $100 bike is a curse instead of a blessing. > > Best, > > Jeff Saline > ABC # 4412 South Dakota Airmarshal > Airheads Beemer Club www.airheads.org > The Beautiful Black Hills of South Dakota > 75 R90/6, 03 KLR650 > > . > . > __________________________________________________________ > 57 Year Old Looks 27 > Local Woman Reveals Wrinkle Secret That Has Doctors Angry. > http://thirdpartyoffers.juno.com/TGL3141/4ef896d589e6954aeb8st02vuc > > [Non-text portions of this message have been removed]