Give it a try - the penetrant won't hurt anything. But engine oil can congeal, too, so pull the drain plug & see if anything comes out. If it's still liquid, put the plug back in & top it up before cranking. If it's thick or dry, even turning the crank by hand could break the oil pump driveshaft, so don't. Just pull the engine out. Tearing it up in the truck won't help you or anyone else. If you don't want to rebuild it (I certainly wouldn't), either buy a reman, or drop in a newer complete used running engine (EFI, FTW!). That's the ONLY way I "fix" carb engines any more.

http://www.supermotors.net/registry/3536

 

Well after about 10 days of soaking the cylinders with diesel fuel, It finally freed up the rotating assembly. Every other day I would hit the starter a few clicks at a time, then would pour more diesel in, and wait. It finally gave in. So today I put in a new water pump and thermostat, here's what I found when I pulled the radiator hose off the housing.

 

This wire that goes from the distributor to the coil was chewed up by rats. Does anybody know if I can get a replacement wire, or will I have to try to fix it?

 

The coolant looks like someone has overloaded it with stop-leak products. I suspect you'll find serious problems with that block, heads, &/or head gaskets.

The distributor pic is too small to make out, but in general: wires can be repaired, replaced, or upgraded. If you really want to drive & enjoy the truck, I highly recommend an upgrade. My first choice is always MODERN EFI.



BTW
Packrats aren't known for gnawing; they're known for packing.

 

Stop leak was my first thought also, but after closer inspection, after I pulled out the thermostat, someone had siliconed the hell out of it, inside the housing around the thermostats edges(My guess to keep it in place while installing). When I drained the radiator, and pulled the hoses off, the coolant that came out looked surprisingly fresh(nice green color and not congealed at all). If flowed out of the block and radiator like if it had been put in last month, not 15 years ago. I'm hoping the coolant that surrounded the thermostat, over time, had a chemical reaction with the silicone in that area which caused it to jelly up like that.
Here's a better pic of that wire. So far I've counted 4 wires that have been gnawed at. I'm still cleaning up leaves, twigs, grass, cactus from crevices around the engine bay.
I am an electrician by trade, and I have worked on a lot homes that have had fire damage due to pack rats chewing on wire insulation, which in turn causes short circuit fires. They are some gnarly little critters. They might be known for packing, but they have many other talents they're famous for also.
I'll be honest, I have thought about maybe pulling the engine if worse comes to worse, but I gotta tell you, Fuel injection really makes me think twice about it. Too many wires, sensors, ECM, etc.,( and I'm an electrician). There's a guy parting out an 91 mustang 5.0. not too far away from me. We'll see, Maybe that's the ticket.

 

There are less than 49 wires for EEC-IV EFI, and several of those are duplicates.



But if there were 500, you don't have to mess with more than maybe a dozen. The rest are already done, inside the harness that you're not building. Look at this & the NEXT several pics:



More importantly, if there were 500: it's WORTH the effort. Driveability, reliability, fuel economy, emissions (no matter where you live, or where you might move to, or where a prospective buyer might need to register it). I've been fighting those issues on this MGB for years, and I almost have Lisa convinced to let me put a Miata engine into it.

 

I think you should pull that 302 out, clean and rebuild it the way it is. After 15 years you will probably have to rebuild the carb.

 

My first car was a 71 Ford LTD 2dr with the 400 and I got it when I was 16 years old, so that was around 1979.. You could still get "leaded" gas back then too...

It had the larger fuel filler hole for leaded gas, but it needed like 89 octane which it said right on the air cleaner sticker for the time.

I used to mix it with a 50/50 mix of "regular" leaded and "premium" unleaded of the time.. I did do an engine 'overhaul' of that 400 around 1982 and I did have the heads 'rebuilt' to handle straight unleaded gas... I think it was just the valve guides/valves themselves that was the difference?? (that was a LONG time ago, so I don't remember... )

I do remember that Dad had a 73 Impala that was "unleaded only"... It had the smaller fuel filler neck and no way you could put the "leaded" fuel nozzle in it.

His 71 F250 was full on "leaded" gas. I think the trucks of that era didn't have to go to unleaded until at least after 74?? I'm just guessing on that of course..

But, what was already said, if the fuel filler neck is large, it needed leaded gas.. If it was small, it needed unleaded gas..

Mitch

 

I got the large filler neck hole on my truck.

 

You should on a 73. Unleaded wasn't mandated on a F100 till 75, that was the first year of the catalytic converter. A 73 did not "need" leaded gas, all domestic light duty engines had hardened valve seats and low compression to allow low octane unleaded (91 RON, 87 pump octane) starting in 1971.

 

Well, I got it up and running today. It took me a while to get it to fire up. It smoked like crazy. After it burned through the diesel fuel, it cleared up. The idle smoothed out somewhat after about 5-6 minutes. I turned it off, and to my surprise it fired right up again with no hesitation. I had a line going to a two gallon gas can temporarily, it ate that up extremely quick. Now that I know it will run, I'm gonna see about cleaning out the real tank. I'm afraid of what I'm going to find in there.

 

One more dilemma, So I ordered a new sending unit from Rock Auto. The original sending unit has two lines on it, send and I think return. The new sender only has one line. I've been looking all over online, and all the aftermarket/replacement senders only have one line. Is there something I'm missing. And if this is the correct part, where do I hook up the return to?