Saturday, November 26, 2011

repaired Stargrazer!

I was very happy. I successfully affected repairs to the Stargrazer at the CAO.

Everything was in place on Saturday morning at the Carr Astronomical Observatory to work on the Motomaster riding mower with Briggs & Stratton engine. Even though it slowly dawned on me that I had forgotten my electronic toolbox back in the city!

At breakfast, I looked over the new parts that I had ordered and that Tony had picked, paid for, and brought north. In fact, when he dropped in to Kooy Bros new spacious shop, the brake actuator had just arrived, out of back order. But I wasn't too excited about the brake arm; I was most interested in the solenoid. I suspected it was the culprit in our no-start situation. So that was priority one. I also checked the pinion gear for the starter motor. Oh ho! New design. The redesign with metal teeth suggested that others had been running into trouble like us. And finally, there was the new oil dip stick tube seal. Dietmar had charged up the lead acid batteries a couple of days before.

As I readied for battle, Trevor asked if he could help. Sure! We took the new parts, a hot cup of coffee, the Fuji camera, my snap ring pliers (with interchangeable tips), tie wraps, the 2008 lead acid battery (which seemed to be performing better than the 2009), and the intelligent battery charger to the garage. Found the lawn mower still on the ramps.

10:33 AM. After taking some photos of the old and new side by each, we swapped the solenoid. Initially, I connected the power leads incorrectly. Once connected, we tried to start her up. I turned the key, the solenoid clicked, and the engine turned! w00t! Power and good lines and a solenoid doing its job.

The engine didn't seem to want to start. But I didn't think it a problem in the engine itself. It sounded like the starter motor gear was not working. No surprise there. So, it was onto the next step: new gear install. This I was most anxious about, with the small snap ring holding the cap and spring in place. I was not sure if my snap ring pliers would work.

We pulled the plastic starter drive cover and main engine outer metal blower housing cover off to give good access to the starter motor. Oops! Almost forgot. I asked Trevor to disconnect the battery...

We returned to the C-clip. And while not a perfect match, we found the snap ring pliers did work. Spreading the ring open slightly allowed us to coax it over the top of the shaft. And the tapered top allowed us to get a good handle on it, before it went flying! I had brought my two types of circlips, just in case. Carefully removed the metal cap. The spring was next. The spring appeared to have some fabric spacer or washer on top, slightly damaged. And then I tried to spin the old pinion gear off the clutch drive. It wouldn't clear the engine gear ring nor the inner blower housing. This required loosening the start motor mounting bolts.

11:13 AM. Photo'ed the old and new gears. Finally we installed the shiny new gear. Reinstalled the spring and cap. And then stared at the clip. How would we get this on?

We tried a few ways without success. The edges of the clip were too rounded for the snap ring pliers to work. Tapping down over the top of the starter shaft taper seemed like a possibility. Borrowed a hammer from Charles and tried a hex socket to drive it down. It wasn't a good line. No joy. Went back to spreading the ring with the pliers. Ping! The C-clip had disappeared! Trevor started looking around the front of the mower but I knew it had not gone far. It had gone inside, inside the inner blower housing! OK. Time to remove it. And it was good we did!

We found gobs of yellow fiberglass insulation packed all around and through the fins of the cylinder and the head! Damn! Sucked up by an inattentive operator? Or pulled in by a nesting mouse? We carefully plucked the spongy material out. It was easier on the right side of the engine where there were openings in the cylinder heat shield. The left side was trickier but finally cleared it. Wow. No wonder the mower was running hot! Ah ha! Trevor spotted the retaining ring! Just under the magneto. Yeh.

With the inner blower cover off, it afforded excellent access to the top of the starter, so we tried hammering on the clip. Still no luck. With no other option, we forced it on by coaxing it around the groove with a combination of the snap ring pliers and bent-nose pliers. It worked! It distorted or opened the clip a little but I was able to force it to compress and then nestle in the top cap.

11:28 AM. Stupid little 5 cent part, as usual, giving most of the trouble.

OK. Now I was keen to see if we had a working mower. Dietmar had asked earlier who would be the test pilot. I wanted the job. After Trevor hooked up the negative terminal and we cleared the foot wells of tools and parts, I climbed in the seat. Throttle low, choke on, in park, neutral, brake on, key to on... I turned to the Start position. She fired up! Yes! Amazing. I was overjoyed. What a great feeling.

12:06 PM. We reinstalled the inner blower cover and the front and rear brackets. We turned in the new seal into the engine block. Screwed it in so it was completely flush with the metal of the engine. Then we test-fit the dip stick tube. It was a good tight fit.

It was time for a test drive. She started up right away. I rolled her off the ramps and out of the garage. I headed over the house where Tony, Dietmar, and Phil were chatting. I updated them. They were curious to see how the starter motor worked. So I shut down and then restarted it. With the starter motor cover still off, we got a good look at the clutch raising the pinion gear into the flywheel teeth and then disengaging once the motor caught. The thing was starting easier than ever before. We were all really happy.



12:22 PM. I reversed and headed to the garage. It was a little tricky finding right shifter position with the forward/reverse lever, without the cover plate, but all worked well. The main hurdle surpassed, it was time to work on the oil dip stick tube. And it was lunch time.

Ironically, Tim arrived a few moments later. I was grateful for his support last week, comforting me that my train of thought was sound. Clearly, the solenoid and the starter motor gear were causing major problems. Now the Stargrazer lawn tractor was back in business.

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After lunch we buttoned everything up.

We reattached the outer blower cover. We test-fit the dip stick tube once more and observed, again, that the markings on the blower were higher than were the dip stick mounting plate wanted to lay. I suggested a new hole in the blower cover, down, and a little to the right, would allow for a new mounting point, while leaving some metal between the old screw hole. Trevor agreed. We borrowed Charles cordless drill and probably the dullest bit in his kit but at last we were through. The self-tapping screw went in fine as Trevor applied pressure downward on the dip stick. Engine repair done!

Reinstalled the shift cover (with cutout), after reattaching the kill ground wire to the reverse safety switch. Reinstalled the rotating cover atop the flywheel fan. And rerouted the wiring near the dip stick and the starter motor, primarily so to make draining the oil easier in the future. Secured them with a tie wrap. Trevor cut off the excess. Checked the oil level and added a splash.

And, at last, cut some grass!

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Every once in a while, someone from the house would come by to pick my brain. They were working on the IP wireless camera. I'd give them a suggestion and they'd head back indoors.

I noticed Tony and crew pulling the new security wiring through the underground conduit.

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