Rzeppa
Rising Sun Member
It was pretty sudden. The PO had installed an aftermarket temp gauge in one of the spots on the t-stat housing where one of the BVSVs normally goes, plus the factory sender in the back of the head still works. I always monitor my instrumentation pretty regularly, and saw both gauges start climbing way faster than normal for just pulling a long hill. This rig normally runs cool as a cucumber and I've never seen the aftermarket gauge go higher than about 200°F.
So I immediately pulled over and shut it down. I popped the hood and saw where the rad cap had spattered a little and the overflow tank was full and had a little spattering coming out the cap. The hoses were all fine. I let her sit for about 15 minutes and started it back up, thinking that running the cooler stuff that had been in the radiator through would help. But instead both gauges climbed up to where they had been, plus I got a gigantic cloud of white smoke out of the tailpipe. So I shut it back down, got out and then noticed a great big puddle of coolant....under the muffler!
So the water jacket's talkin' to one or more cylinders. I knew then I wasn't going anywhere under my own power except on to a trailer. That's when Trevor (Isotel I think?) from Colorado Land Cruisers pulled over with his trailered trail rig, and Jeff Zettl stopped too. Trevor pulled his trail rig off and took me and my rig to Safari Ltd.
They got the head off yesterday. It wasn't obviously cracked and it's been sent off to the machine shop to get magnafluxed and if it isn't cracked then they'll deck it flat and send it back.
They said cylinder #6 looks like it got really hot at some point, and is blued, and that the top of the piston looks like it got really hot. They were going to send me some pictures but I haven't seen them yet. I think I know what that was about; when I was dorking around with the stalling issue I basically went through all the emissions subsystems and discovered that the HIC system and the distributor cap vents were cross connected. The HIC pulls from a T fitting on the PCV and the PCV bungs to the manifold at the rear, so it basically had a vacuum leak at the rear of the manifold for however many thousands of miles until I corrected it last summer. That would make for an overly lean mixture in the rear of the intake and make for high combustion temps. I'm glad it didn't burn up the exhaust valve.
