- Mar 31, 2019
Your choice on the head gaskets. stock ford gaskets back when broncos were built were clad in steel after time the steel corrodes and the gaskets fail. the more it sits with bad coolant the worse it is.
You just might be right...see below update...
Got the tank selector valve installed and plumbed. This is the aftermarket valve, and it's just not a good fit because of how the fittings are configured. I ended up finding a good used one locally (maybe from a '73 Bronco?) that's similar to my original one. I'll either use it, or just parts from it to rebuild my original one.
Got the radiator installed and then managed to snap off two bolts for the fan shroud mount. Par for the course for old rusty stuff. So I pulled it back out, drilled out the bolts, then tapped to the next larger size. Then I noticed the fan had some interference issues with the fan shroud, so that took some tweaking... As usual, what should have been a 5 minute job ended up taking well over an hour.
When it was all back together, it wouldn't start. Realized the rebuilt fuel pump wasn't pumping, so I swapped it out with the generic parts store pump that was on the truck when I got it. Truck is running again. I'll have to disassemble the original pump and see if I can figure out went wrong.
Anyway, I got it all back together, and running. No interference issues with the fan. Fuel pump is pumping fine, no fuel leaks, tank selector valve is working, freshly painted correct crank and water pump pulleys are good to go with perfect alignment and no squeaking, etc.
I did notice some coolant on the passenger side floor after it ran a bit, so my heater core has a leak. That's not surprising at all, so I yanked the heater hoses, put some rubber caps on the core inlet/outlet, and connected a single hose from the water pump to the intake.
Once that issue was addressed, I figured I'd work on tuning it a bit. Seems to like about 12* timing at idle, but before I could get timing and mixture really dialed in with a vacuum gauge, Murphy struck again...
I'm getting a LOT of smoke coming off the driver's side of the motor once it warms up. It's coming from behind the exhaust manifold, and it's thick white smoke. What's weird is that it starts all at once; it's not there until it warms up a bit and then it comes on like gangbusters. Checked oil; not milky at all. Not leaking oil from the valve cover. No evidence of oil in the coolant, either. I also did a compression test on all the cylinders in that bank and none were changed from the original test.
Bottom line - it's either a head gasket or a freeze plug has a pinhole leak spraying on the exhaust manifold. Either way, the motor is coming out, and if I'm going that far, I'm going to tear it down and rebuild it. Should have done this a while back, given what I've had to do with the engine still installed, but live and learn, I guess.
I'm a bit torn on the way ahead. I have two Broncos. One that I'll keep and one that I'll sell. The keeper is going to get a nicely built 347 with good heads (AFR aluminum with 170cc intake runners and 63cc chambers, I think), the NP-435 4 speed, and the Dana 44 front diff. The one I'm going to sell will get a mild 302 (rebuilt, .030, small cam, good intake, carb, etc), Dana 30 up front, and probably the C4 automatic.
Had planned to sell this Bronco and keep the '68, but may end up flip-flopping because this one is definitely more solid.