Feels good, doesn't it, Matthew? Congratulations in reviving the dead.

I also suggest a leak-down test, at least just filling up each cylinder with and listening for escaping air; measuring the quantity & rate requires one of those fancy setups and I've never bothered with that part.

 

Our Sun engine diagnostics scope has a leak down tester, and it works. I'll have to hook it up. Not only is it running, but that transmission that had been slipping for 20,000 miles is back from the dead, it was only low 4 quarts or so. Tough piece of crap eh? doesn't seem to slip at all and shifts in and out of gear. I haven't driven it yet, but it 1 and reverse works the rest most likely do as well. After all, this is the second time it's been revived from the dead and it worked fine last time. We'll see.

I about crapped myself when I was revving it up and reverse decided to work. Good thing I was in the gravel otherwise there would have been some tire smoking lol.

 

Yes, the gasket must be the problem. Fix that and the leak-down test is moot. Congrats!

 

Today before I started it I tightened up the bolts slightly more around cylinder 4 intake port, now after the engine gets good and hot the vacuum leak misfire goes away. Runs great. It also now has coolant in it instead of flushing it twice with straight water the other day. (Did not leave it in overnight), No block drain on this one and the bottom hose is impossible to get off without loosening the radiator. So, run and flush lol. Good thing the thermostat works like it should, didn't replace that.

 

..........

 

I plowed. I really like that truck.

 

Adjusted the carb on my '56 and my '82. Ran my '78 Mercury, still runs like crap as it needs a carb rebuild I guess, I also have some plastic aircleaner temp sensors that are broken leaking air, I also have a choke pull off leaking air as well as a accelerator pump that spurts fuel every now and then.

I also put new air cleaner on my truck and was going to replace the PCV filter but the auto parts guy which ironically is older than I am wanted to know if the PCV filter was known by any other names as their computers don't show it. Had to tell him I don't know what else it could be called as its a foam filter for the PCV system.

I also picked up a bunch of fuses, vacuum caps, and vacuum adapters as I broke my 3/8 to 1/4" adapter I was using on my '56 when I hooked my vacuum line to the brake booster port.

 

Installed this the other day. My am/fm radio (aftermarket) didn't work and I like listening to the truck when I drive my older trucks anyway.

So out with it and in with my vhf radio. Fit nicely.

 

...........

 

I changed the intake gasket on the car today, seems to run much better, throttle response is 2X what it was and it idles smoother. Hopefully no more codes.

 

Alright, that engine has some sort of a compression problem on cylinder 4. I tested the ICM, did an OHMS test on the coil packs, which doesn't mean much. I ran another compression test on cylinder 4 and at times it will go 3-4 times around without building compression then the next time bang it builds a lot. I gave it a good squirt of oil and it seems to get a little better. I'm pissed. Time for a leak down test. It won't pass emissions throwing the misfire code every 10 minutes, so I'm not even gonna try that.

When I pulled the sparkplugs when I took the engine apart they were all nice and uniform colored, now cylinder 4 seems to be a tad bit darker than the rest.

This kind of symptom reminds me of a valve not sealing properly.....

 

3-4 times around without any compression is a major problem... you probably don't have lifters & pushrods so there really isn't much else that could be causing the problem....

 

Yep, and I doubt rings would cause that. As when it does build compression it builds a lot. Almost as if the valve is walking sideways closing and not sealing sometimes or something. I'll do a leakdown test this weekend when the van is out of the garage.

The WEIRD thing is when you put a load on the engine or get it up in the RPM's or just simply rev it up it does not misfire at all. It also seems the hotter the engine gets and the longer it runs it pretty much goes away. If you give it the Italian tune up technique it doesn't really do it afterwards for a while. WTF?! seems worse cold. Ugh, cars.

 

That's what you get for buying a GM product...

 

It might do that with a bent valve. Or something else causing the valve not to seat every time. But, you lapped the valves in so would have noticed a bent one. Dunno.