Way cool. I'm a fan of the Y Block, so I am wishing you the best success with getting it fired up!

Put a vacuum gauge on it and see what it's pulling at 550 RPM and report back.

The semi-semi is cool! (as is the 56), Good luck on getting her going again.

Sub'd!!

And I love that semi!! Awesome! I'd drive that everyday!

I got the nasty gas out of the tank today and had a peek through the sender hole.....
Not good.....very rusty in the bottom.
Will rig up a temp tank and scare up a battery in the next few days....
Likely need to pull the carb and see what's inside too.

Don't know how your friend could have stood for it being untouched for two years! I was climbing the walls when mine was away for 3 months and they didn't do anything to it, except damage it while it was in their workshop.
Good luck with!

You are doing a great think for your friend. The world could definitely use more people like you.

Little update.........I did a compression test on the Y block today. Most cylinders were 130ish, not too bad. But #7 had none, so I pulled the valve cover to check for stuck open valves. Both are working....not sure if they are sealing. Broken/stuck rings?
Also #1 is blowing back into the intake? Not looking good.....

Y-blocks are tough engines, takes a lot to hurt one.

Compression test done with carb held at WOT, all plugs out, 2oz oil in each cylinder and then crank for a while, then check compression? If not, don't worry about low #7 or #1, if it has not run in a while, valves might be not seating and rings not seating.

After you put oil in cylinders and crank it for a while, put shop-air into spark plug holes on #1 and #7 to confirm where that air pressure is going; out carb, out exhaust, or into crankcase.

Even with one really low cylinder, I would start it to see what it runs like. Put Marvel Mystery oil, about 2 oz, into carb ( no gas) and then crank it to start. That oil will burn and also lube valves. If it fires then dies, do it again, then hook up gas line.

Run for a few minutes. Shut off, pull plug on #7 and check compression.

Good luck!

After some more checking.......The #7 exhaust valve was tightened down so much it wasn't closing, and the #1 was too loose. Whoever was adjusting the valves was clueless.
Got them all pretty close, will try to fire this thing over the weekend!

I'm a little concerned about the cams condition....some of the adjusters are at their limit....

How about some video of the firing?

If adjusters are at their limit...... I suspect bent pushrods. Pretty common on old Y-blocks that sit for a long time, valves stick and it bends pushrods.

Got the Y block fired up today. Still have a lot of racket from the valve train....gonna pull the push rods and see what's up. I didn't run it very long, the water pump is leaking too.
Now that I can move it under it's own power, I'll get it into the shop and dig a little deeper....

I'll bet the rocker shafts are full of crud. Sitting and who knows what maintenance (if any) probably has the engine all sludges up. A couple of oil changes maybe with sea foam and a valve adjustment may quiet down the valve train noise. Pull the valve covers and see what it looks like.

Sweet, it's running. Keep the updates coming; pics too if you can. How many years since she moved on her own power?