I’ve been away from my two blogs for a little bit, though there have been some developments in both, especially this one.
Biggest news, Gabby got a CanAm Spyder RT!
One of her friends at work needed to sell his just as she was shopping for one, so good news for them both. It’s a 2010 model with a 5 speed manual transmission. It will flat scoot if you ask it to.
Last time, I was talking about the trials I was facing with the tank that does not end. I requested a quote from Boyd Welding and at just under $200, it is not a cheap tank by any means. It is competitive with commercially available racing fuel cells and none of them are the right shape. In any case, I went for it and it’s expected around the end of the first week in October.
Before Labor Day weekend, we participated in school supply benefit run. Kermit had some reliability issues wherein he would occasionally flood out and die at a stop. One of these times involved her being towed the last mile or two to the school, an activity she is glad to never repeat. Long story short, it seems to have been that the 5 PSI fuel pump overwhelmed the 3 PSI float valve. The installation of a fuel pressure regulator seems to have abated the problem.
Since it worked without difficulty for a long time, I suspect the overrating has probably mildly damaged float valve. I have carburetor rebuild kits waiting for me to install them.
That same day, SpongeBob was running ok, but not great. It was taking wide open throttle to reach freeways speeds. I tolerated it for the day, but over the next few days, I did some troubleshooting, including new distributor cap, wires and sparkplugs, to no avail. The troubleshooting seems to indicate that he had lost power in cylinder 4 and that either 3 or 4 was filling with oil when it sat overnight, which can’t be good.
I shopped for another engine, and not really finding anything I wanted to pounce on, I decided that I would put the old engine from Kermit in SpongeBob and rebuild SpongeBob’s engine. It’s a slightly better candidate since it’s crankshaft pulley isn’t welded on and the mild oil leakage from Kermit’s old engine would be tolerable in the short term.
So, I moved all the bits over, alternator, intake, carburetor, distributor, oil cooler.
Started it up.
Hmmm. It runs almost exactly the same, no power from cylinder 4 and that pipe is barely warm. It runs just was well with our without a plug wire on 4. I connect a spark plug to the #4 wire and there *is* a spark, though admittedly, it looks a little weak. I dug deeper and found that the contact on the points was far beyond merely worn. They were eroded almost away, essentially missing.
I had a new set of points and changed them out. Fired right up and after a few minutes tinkering with the gap/dwell and timing, SpongeBob runs great!
Lesson learned: Severely worn points can make a single cylinder loose power. Essentially, the dwell was short and contact resistance was high, so the coil likely was not able to saturate. This provided a weak spark on all cylinders and probably a very weak spark on cylinder 4, probably due to very small dimensional differences between the lobes in the distributor. I may have been able to adjust the points such that it would have worked, but they needed replacing anyway. Tinker tells me that this is what points look like when the key is left on for an extended time without the engine running.
The oil in the cylinder still means a rebuild of the engine is advised, but I might have been able to put off swapping engines.