On the saga of the overheated engine that I am pulling out of the Wonderbus today. Summary: alternator belt broke, engine turned off as quickly as possible given traffic and parking spaces (1/2 mile).
Cylinder #4 leaks badly. Burned exhaust valve, punched-through piston, whatever, I'll find it today. I'll also inspect all the pistons and cylinder walls and valves today.
But here's the thing: the entire engine became hot, of course, not just #4. #'s 1 and 2 pass the simple compression test. I'll eyeball #3 today.
My question is: is this a go/no-go situation? Could this overheating have weakened the other bits so that while they might work fine for a while, they may fail soon? Would a prudent fellow just replace all the valves (or other bits) even though they look okay?
I'm looking for the prudent things to do at this time, since the engine is out anyway.
On Wed, 26 May 2004 08:17:49 -0700, "Mike Rocket J. Squirrel Elliott" wrote:
v Gee that sounds familiar. Dec 94; I let my wife drive "buttercup" that day. When the battery light came on, she thought she had until the battery ran down. It was freezing-and-pouring-rain-and-dark, so she finally got off the next Interstate exit well after it started to loose power [*nearly 2 miles later*]. The smoke from all the non-metal engine parts was still bellowing out 30 minutes later. I was surprised the fire department didn't beat me there. v A local machine shop rebuilt the engine [turnkey] in the same case, because I had had that [Mex] case converted for hydraulic lifters, so I really wanted to save the case. There were many problems. I *think* some sort of melting crud jammed up the mechanical advance in the distributer at that time and maybe even clogged up the vacuum ports on the carb. The resulting timing problems probably the cause of the re-cracked heads [I think they had been welded during the rebuild] and a scored #3 requiring another partial rebuild with new heads and a single cyl/piston a couple of weeks after I got the bus back from the shop. It runs good, but I've never felt good about a case that had been so hot, and I've always thought the persistent oil leaks were related to that. It leaked oil out the back from day one, and it still leaked after the engine came out to fix the oil leak. The previous instance of that engine was always "no spot." good luck. I guess if you can do it yourself, you're not out as much as I was. I doing it myself from now on.
---end--- Loosing the previous engine wasn't a total waste, because it was screwed up too. It had a cheap counterweighted crank with dowel pins coming loose so the crank couldn't be reused. Those drop-in 87mm cyls weren't going to last long in a bus [although they made the heater work great.] At least the later engine was kept nearly stock.
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