Spark plugs, carbs

Hawghunter wrote: I have been going on some short rides. 15 - 20 minutes. After each ride the oil level is a bit higher. Started with it at the low level After two rides it is at the halfway point. I don’t understand how it can do that with the engine running. It sat in garage 4 days, no increase in oil level. It seems to be running just as it had been prior to the high rev start. All four pipes are reaching the same temperature. There is no fuel leaking from the bottom of the air box. I pulled the fuel hose off and the tank does not leak when set to the normal setting.

Are you letting the engine cool to ambient temperature and is it on the center stand when you check the level?

TexasKZ wrote:

Mikaw wrote: Do you have an oil cooler? If the hoses trap the oil in the cooler and you change the oil and fill to lowest level, then start the bike the extra oil would get pushed into the crankcase while running. When parked the oil would return to low level as the oil is trapped in the cooler again.

The oil level in the sight glass will be higher normally when the bike is running.

I do not see how this is possible. The reason that the oil is pushed out of the cooler while the engine is running is because the pump is removing oil from the sump and forcing it into the engine and cooler. For every cc that comes out of the cooler, the pump has taken a cc out of the sump.
I do not think I have ever had a bike that I could see the oil in the sight glass with the engine running. When the engine starts, the oil pump begins removing oil from the sump and pushing it into the engine, so the oil level in the sump is noticeably lower.

I was thinking about the oil just exchanging places after I sent that. so I agree. I dont think I have ever looked a the site glass when running. I assumed it would be sloshing around and more visible .

Attach clear tubes to the carburetor drain ports, Tie them up so you can see fuel level. Check at idle and go for a ride and check often. This should show if a carburetor is overflowing.

You are going to think I made this up. I did not.
I went down to run the kz. I wanted to see how long it would take to have the oil over full First I drained the bowls into a bucket. 3 & 4 lots of specks. 1 had fewer. 2 was clear. Got her warm. Warm enough to find I have a weak coil. Coil dropped, running on two, so shut her down. Enjoyed my bonfire a bit then checked sight glass.
It was back down to the level that I filled her to after the oil change. Today I did a short warmup. Oil returned to the same level as after oil change.

The oil fairy is messin with me !

Got my new battery in and started her up. Oil level near the low lines in sight glass. Had to switch to reserve during warmup. Went to fill. 3 gallons and only 93 miles, with a few startups in garage. 15 mile ride around town and then back home. After shutdown oil level very near the top lines in sight glass.

Seems to be running much as it has all year. After shutdown I noticed the the left vent line had been dripping, right line was wet inside but no noticeable drips. As the vent lines are way above the float bowls and the engine intakes I do not understand how the vents could be dripping. The air box drain port was dry. I do not have the bowls with the overflow ports but now I wish I did.

If fuel is overflowing in to the engine intakes wouldn’t it be flooding out? Even if it is how could it drain into the sump while the engine is running ?

The oil level in the sight glass is only meaningful when the motor is not running, like Texas said.

If that bike is stock, then no oil cooler.

The carbs should be Tk22 carbs which do have overflow tubes in case the bowls get too high. They drain out through the drain pipes in the bottom of the bowls.

If you follow the links in my signature there are several manuals you can download which describe the carbs nicely.

Also, here is a Tk22 site with some info not included in the manual:
s3.amazonaws.com/gpzweb/TK22mainPage/TK22mainPage.html .

A bit off topic, make sure all of your exhaust pipes are about the same temp when running.
Infrared thermometer on a non-shiny part-maybe the exhaust flange or spray water on the pipe to see if it boils off at the same rate.
I'm just curious if all of your cylinders are firing as you mentioned the engine had a turbo-like whine at one time.

I have been using an infrared thermo. All alike area temps match. Took me awhile to realize The shined areas don’t work!

I am reading the site glass while off and parked in the same spot in the garage.

My Kawasaki manual shows no carb drains in the 1981 and newer. Emissions issue I believe it says. I can see the bottom of the bowls do not have the ports drilled.

I am wondering if the stance of the bike allows an overflowing bowl to flow back to the air box and drain into the crankcase breather without also flowing out of the air box drain. Maybe the time that the oil level returned to the lower level the float worked properly and the motor was hot enough for the fuel to vaporize and be pulled out to the rebreathers and burned ? Just spitballing here.

Thanks for helping me work through this. Today I will flush the bowls again to see if more debris is there.

All Tk22 manual-slide carbs from any year came with bowl drains and overflow stand pipes inside the bowl, all the way up to their last year which was 1983 on some models. It looks like you have the stock Tk22 carbs in the avatar photo if that's your bike. If your overflow pipes are sealed then it's a modification.

Inside the bowl, there should be a small brass pipe coming up from the drain screw area. That is the overflow pipe.

The non-overflow carbs started in 1982 and they were Tk26 cv carbs, but they may have been manufactured in 1981. They are easy to identify since they have large round chambers on top for the diaphragms.


When it overflows through the carb throat, gas will just follow gravity, so it can go into the engine or the airbox depending on how the carbs and bike are angled.

I believe this is what I had read. Missed the part about it being a different carb. Now (as usual) I am confused as to how an overflow wouldn’t flow out the bottom

Ed (Nessism) is referring to Keihin CV34 carbs in that photo. I think those are for a Kz750, (maybe Kz650, not sure). But those are not found on a Kz550. The Kz550's use Teikei brand carbs. The thread he was replying to was about an 82 Kz550H which uses Tk26 cv carbs, and those do not have an overflow tube, so his post still applies to that bike.

Your Kz550, specifically, should have Tk22 manual-slide carbs (as I mentioned). They definitely have an overflow tube. The drain screw on the bottom is actually a valve. The screw does not need to be removed to drain the bowls. The screw just needs to be loosened and then fuel will drain out through the drain tube on the bottom. This is how you do a fuel level inspection with a clear tube etc.

When the screw is all the way in, the drain function is sealed off, but the overflow function should still work. If it does not, then it has been modified, or more likely it has been clogged with dirt. If you remove the screw, you can clean it out and maybe blow out the overflow tube with a syringe and water. Be aware, the drain screw has two orings on it and they may need to be replaced.

Yes. I have the carbs you state. I drained fuel again and all was clear I forgot to lightly blow air back through to verify the overflow tubes are clear. This week I left the bowls empty while I was gone. Will see if any fuel got into the bowls when I return and then blow through the overflow tubes.
I’ll check the oil level then too. It was a bit lower a couple days after my previous ride. Now it will have been a week.