Mercy! Mercy! That Dang Nabed PERCY!

Boiling a carburetor to unstick the slide body

Recently I went up to Fargo ND and picked up a 1972 Kawasaki Bighorn motorcycle.

To provide some background I had one in 1970. I'd just returned form my first tour to Vietnam. Naturally I had to enter it in an Enduro and the experience left me in a complete state of exhaustion after one hundred miles. My hand locked up so I couldn't even pull in the clutch and had to break using my finger on the compression release. There was one great memory that came from the experience. I was told that John Penton would be somewhere out on the course watching the spectacle. Fat chance of ever seeing him. Anyway early in this enduro I came to a steep hill. It had just started to rain and there must have been one hundred bikes milling around the bottom and not having much luck getting to the top. Undeterred I picked a line off the trail, gunned the engine and popped the clutch. My motorcycle did an unexpected wheelie and and took off for the top. I held on for dear life and couldn't get my wrist over the throttle and barely kept from flipping as I zipped between trees in a miraculous display of sheer good fortune. My line took me straight to the top where the great John Penton was sitting on one of his bikes. He got off as I approached the top waving me on. "Great Ride!" he cried out. "Great Ride! The front end settled to the ground as I reached the top and he came over and slapped me on the back. I was still wide eyed with terror realizing I had only survived the attempt by a huge stroke of good fortune. He pointed to the path and the trail descending the hill. It was a descent that would have done a rollercoaster designer proud. Still I didn't care, after the trip up the ride down was a piece of cake. Not to mention I not only met the great man but he complimented my riding.

I always loved that bike and lamented ever letting it get away from me. After I retired I tried to find one but the price was always too high. Then last month three came up for sale on Face Book, of all places. I normally search Craig's list and within the period of a week I bought three, one for $1400, another for $900 and the latest for $800. And there they sat, until yesterday when I finally decided it was time to see if I could get one to crank. Keep in mind all these bikes had been sitting neglected in a garage for the last half century and were parked because something was wrong with them.

So I put the first one on my lift and cranked it up to working level. The engine was seized up and the seller could not shed light on why. Hopefully it got bound up as a result of sitting for a long time neglected. The first thing I did was remove the case beneath which the carburetor resided. My impact driver did not have the right tip but it worked anyway. As the case came off my heart sank. It had been parked in a filthy state of neglect. The carburetor for the rotary valve was inside a protected case however, it was so full of crud it looked like it had been submerged in water and mud and never cleaned up. My hopes that the engine seized form disuse changed to the likelihood the seizure was more mechanical in nature.

Not only was the engine seized but so was the throttle body in the carburetor. It was stuck and gently prying after spraying with WD 40 and a host of carburetor cleaners did nothing. Removing the idle screw showed the tip to be pitted with corrosion. I was discourage but instead of going further and doing some permanent damage decided to go watch some U-Tube videos and check out some of the forums. I wasn't having much luck until somebody showed boiling a carburetor on the kitchen stove. Unfortunately my throttle cable was stuck inside and I didn't want to cut the cable to get the carburetor out of the engine. Then I had a flash... why not take a Coleman camp stove and boil the damn thing in a pot still hanging from the cables.

On this particular bike there are three cables on the right hand side of the handlebar throttle. One of these cables goes to the the throttle body of the carburetor, another to the choke and the third to the oiler. Yes this is a two stroke engine. The choke and the throttle body were the problems as both were corroded into their orifices. My wife suggested Downy dishwasher soap and water and gave me an old kitchen pot that was no longer being used for cooking. I fired up the gas burner, filled the pot with soap and water and deposited the carburetor letting it boil for about six minutes. In the first session the float body came loose and slipped almost effortlessly from the cylinder. I then unloosened the choke cable and let it boil for another six minutes. This too came out but with a bit more effort. Now all the parts are dissembled and removed and are soaking in the sonic parts cleaner. The first hurdle had a positive outcome. I only hope the next is as successful.... no it isn't getting the piston unstuck but rather seeing if the stator is still serviceable after all these years behind the left hand side cover.