Here is the under column fuse box, and my brake light switch.

 

new thread started

 

So having had the truck for about a year now, reading my FSM, cleaning, measuring, replacing and so forth... This is where I currently stand.

Among all the quirks and symptoms the truck exhibited, the hesitations, stumbling, poor shifting and at improper times. I have performed a proper tune up, and rebuilt the carb. Ignition related issues were still present so I’ve got through and tested all my wiring, and the ESA is actually functional. Also came to find out that at some point Roy (my grandfathers mechanic) poorly attempted to disable the use of the ESA my removing the vacuum line and setting base timing at zero degrees 😑. So I replaced the distributor due to shaft play in all directions with a cheap spectra from the parts store to be drivable since upgrades are planed on in the future.

with the timing set to 12 degrees BTDC and the beat to hell carb about as good as it’s gonna get till I toss on the NOS one in a few weeks, it runs well enough just not pleasant or efficient. Because I believe the valve guides to be shot, and/ or the timing chain along with it (vacuum gauge and Service manual specs point that way) it’s parked unless needed for hardware store run or to take trash to the dump.

Here are my thoughts, on a few approaches.

1. Pull what’s needed to service the chain as well as pull heads and have the guides replaced. Toss it back together with fresh gaskets, and just drive it as is. In a minimally touched form for “Originality” and cash on hand.

2. if the cylinder walls end up needing attention pull it and stock refresh the whole thing top to bottom replacing anything that’s worn over limits. And just drive as is slightly longer down time.

3. if it ends up having to go to the machine shop as a whole anyway, if any major part needing replacement just go ahead and fluff-n-buff the long block for a little better power and a little more efficiency. As well as refresh my leaky trans

or a 4th option of buy a cheap running 318 and drop in then take my time with the matched engine for the truck with a mild build for 270-280 crank hp

opinions, pointers, or anything anyone feels I’m overlooking would be of great input

 

If the budget supports it, and you can afford the downtime, yank the engine, go through it, give it some improvements, and don't worry about it ever again.

 

If you don't have a lot of blow by or oil consumption, I wouldn't pull the heads off if a compression check looks good. What I would do is if you plan to swap another engine in for a bit, I'd leave the transmission in the truck and just pull the engine. You can swap the front seal with it there. Put a decent running engine in and go through your original one. I'm assuming you have around 120K or more on the truck. About time for a timing chain. If you pull the engine, you ca replace the oil pump with a high volume one, replace the timing set as well as the expansion plugs on the side of the block. I'd rinse the block good while the plugs are out. I've usually gotten anywhere from 1/4 to 1/2 a 5 gallon bucket of rust and sand from engine blocks. The sand is left over from the casting process. These blocks will go a long time with just some minor repairs. My last 318 was close to 330K when it finally got to the point I had to replace it.

 

According to my title and paperwork when I got my tag, my odometers accurate at 77k and some change, I think it’s truthfully just internal wear from turn key short trips on a cold poorly maintained engine, neglect and the damage of time.
the reason I think the guides are shot or timing chain for that matter is that I have 16-18 inHg at best at idle, and it peaks at 20-22 when cracking the throttle, but the needle basically vibrates tightly in those ranges, which is what I believe is freaking the ESA out and it’s not giving consistent timing. But that vibration could also be cause by the worn chain due to inconsistent cam movement, and thus not letting vacuum or the distributor function properly anyway. I’ve figured the average life expectancy for a timing set is 60-65k so it seems appropriate. I don’t have any blow by or smoke on cold start and no consumption other then leaks which gives a second vote towards timing chain issues. I’ll get my compression test done tomorrow, and if y’all want I can post up a video of how it runs and drives 🤷🏻‍♂️ And see what y’all think. But I’m definitely on board with the rust/ sand flush. Because if the engine comes all the way out, it’s first date if with some industrial machinery cleaner and a heated pressure washer! However the idea of doing essentially an ‘in frame’ rebuild for the sake of cost and shorter down time is still appalling.

after talking with the wife, if I can find a local halfway decent running engine to use the truck with for several months, and just rebuild the trucks proper engine with some stock ++ bits so I can hang with modern vehicles in traffic. Nearly everything around me is 55, 65, 70 and of course everyone dose 5-15 over 😑.

 

Sorry if i missed something but do you still have the EGR set up on it? I would ditch the boat anchor intake along with the carb. Get a edlebrock intake and holley spread bore carb. The stock carb doesn't have a mixture screw from the pics i looked at. You can take the distributor cap off and turn the crank(both ways) to see how much slop you have in the chain. How about a pic of the motor?

 

I still have EGR, and ESA, that are both functional. Although I believe one issue is the inconsistent vacuum reading causing the ESA to be trying to constantly stabilize the timing? The plugs over the idle screws have been removed long ago and can be adjusted with an Allen key. Truth be told though, if I wanted to be 100% sure I need to get a cheap tach so I have an RPM reading rather then basing it off of audible idle quality. As well as toss one of my old stand alone wide band O2 sensors in the Y pipe before the catalytic converter to measure idle AFRs since the lean burn carb is SUPPOSED to be non adjustable. Here’s an engine picture and the unblock idle mix ports. If someone needs a picture of something specific, let me know.

Complete engine picture,

Air cleaner removed,

Unplugged idle screw ports,

 

Actually, metallurgy has improved and timing sets were good for 120-180,000 miles by the 1980's. I pulled the factory chain out of a 1988 Diplomat and the chain was good, just the nylon was bad. I'll bet that's what your problem is. In the 1970's and '80s the crank gear had a nylon covering to make it quieter in the show room. That, combined with a lot of short runs does sound like you need a timing chain. I'll bet it's flopping inside and that's messing your timing up. I have a '93 GMC and it had a bunch of short runs and the chain had jumped two teeth at 121K.

Myself, I would swap a decent engine in and go through the original. Normally, I'd just freshen the other engine up and stay with that. Being this was your Grandfather's, I can see staying with the original engine. I've just used a garden hose to flush the engine.The engine will definitely run cooler with the passages cleaned. Get a couple of front seals for the transmission. Replace it each time you pull the engine. It's several hours of aggravation for a $20-25 part. I usually leave the transmission in place and brace it up with a piece of wood under it and another one to hold the converter in place. That way, you don't have to spin and press it in for three clicks.

 

that’s pretty much what I was thinking too on both the plastic teeth as well as leaving the trans in the truck. Torque converters a different story, while I’m in there I think I’ll toss a new one in while it’s easy and keep the original for inspection, if serviceable keep it as an on hand spare. I do however plan on also refreshing the transmission when the time comes to put the refreshed engine in, so all things are equal of sorts. Along with the powertrain and its accoutrement when prepared will be odds and ends like radiator, steering, shocks, all new rubber in the bay and fuel system, cleaned or new gas tank if needed. Those kinds of things.

Truthfully time and money are irrelevant because doing it right takes what it takes but like anyone else I’d rather be driving it then it being down 🤷🏻‍♂️.
I want it to be a truck nice enough to just hop in and go wherever whenever regardless of the temp out side, having to let it heat soak before it runs best or having to stay within range of a non ethanol station (yes it runs worse on standard pump) lol. And I’m especially thankful for all the knowledge and cumulative experience and help I receive here
😎