Trike stuff has been slow, but not static. Since that last update, Spongebob has had the most blogable action.
Though it was not immediately apparent, while being stored for a while, Spongebob leaked a lot of oil. Turns out that what really happened is that the fuel tank cap did not vent correctly and the pressure was able to overcome the float valve and flood the engine with fuel, which eventually seeped to the crankcase and overflowed it. This became very apparent when I was rolling the trike out to attend a monthly BTW meeting. It first acted like the battery was nearly dead, which was not unexpected. Unknown at the time, the engine was actually in hydrolock and not able to turn over. Keeping at it, I cleared the cylinders, but when it started up, oil poured everywhere.
Though it would be a few days before I got to it, I drained the crankcase and refilled with fresh oil and started it up. It still leaked oil at too high of a rate to operate, so I presumed the event had damaged the front seal and I again left it for a while.
When our vagabond friend John came to visit, he got interested in effecting the repair, as taking Spongebob for the occasional spin is one of his favorite activities, so I let him tear into it. He replaced the front seal and did a lot of cleanup on the engine, as well as a number of other related work. Even after that, if the cap was properly closed, it would do the same thing. For the time being, we were leaving the cap loose unless the trike was underway somewhere. We also installed an inline fuel shutoff valve. That that seemed to have prevent it from happening at all, though it's not really in a convenient spot to operate all the time.
I opened the cap and reduced the spring tension on the vent mechanism by trimming out a couple of coils. My redneck test of sticking it on my mouth and blowing indicated that I had reduced the required pressure by about half, but in use, it still fails to vent before it blows past the float valve.
I then fashioned a tank vent by putting a fitting in the filler neck and attaching a length of hose to it. There is no pressure build up, so no overcoming the float valve!
In proper followup, I probably need to replace the float valve. Chances are that it may have been damaged by the overpressure situation.
Then comes the day this weekend when we are again wanting to take the trikes to a BTW meeting. I had tried to start the trike the previous weekend when were were attending a birthday party. It would crank and crank, but not start. We were short on time that day, so I didn't do any other troubleshooting. This time, however, I had a little more time and put some more time into it.
I found a badly cracked rubber vacuum cap on one of the carburetor vents. In my experience, that wont usually prevent it from starting, though it can make it run very badly. It took a while to find the package of caps I had, but of course that didn't make any difference. It seemed to be getting spark, but I didn't smell fuel. I started tracing that down and found, surprise, the inline valve was off. Opened it, turned the key on and heard the tone of fuel pump change as it pressurized the system. Hit the start button and he lept immediately to life.
I pulled both trikes over to the house and hosed off the dust; not really a good wash, but roadworthy. We headed in to Fort Worth for the meeting.
As we got close to our destination, the other trike began running rougher and rougher and eventually stopped... in the left turn lane on the access road where we needed to cross over and u-turn to get to the meeting. Try as we may, it would not start. We waited for a clearing in the traffic and I pushed Gabby into a sharp right turn. The road had a bit of a hill on it and she tried bump starting it on the hill and, surprisingly, it started! We were going to try to see if we could make it to the meeting before it died again, but it didn't get far at all. After another try or two at bump starting it again, we gave up and parked it. Gabby climbed aboard and we headed to the meeting, arriving late, but arriving.
After the meeting, a crew of folks went with us to troubleshoot and it was determined that the alternator belt was loose, very loose. Loose enough to prevent it from charging, which apparently let the battery run dead enough to not provide a reliable spark, which seems to be what stranded us. Also why a bump start worked for a bit, with started not pulling the voltage down.
After establishing that there were no shims left to remove in order to tighten the belt, one of the crew produced a spare belt from his parts stock and we installed it. Well, I say we, but nobody made room for me to help, but I let them do it for me. :)
By then, the battery had chemically recovered sufficiently enough to start and the now tight enough belt was actually charging. Long story short, the trike was reliable for the rest of the day and even had noticeably brighter lights. Amazing what you miss if you don't look for it.
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