Sorry to hear. That sucks when you have to do things twice. I would think a tight guide, as everything looked OK when you looked with your borescope. I guess you'll see soon enough...

Love your truck...

Tearing the top end down again. Looks like the valve is straight just stuck in the guide.

Thanks, man. Wish I could drive the damn thing...

You'll get there.
A lot quicker than I will.

At least your piston didn't try to close your open valve for you!

Took the heads back to the shop and they took the offending valve out. It wasn't a tight guide. Somehow something melted to the valve shank when it was open and it jammed into the guide. You could drop the valve in the guide upside down and it was free until it hit the bad spot on the valve. No idea what it was.

He offered to get another valve and install it but I just had him file down the spot since it was only about 1/4" from the end of the guide when closed, polish it, resurface the valve, ream the guide and reinstall.

Since I was in the neighborhood, I dropped them off at my machinist to machine the valve cover sealing surface. It was pretty rough and I can't get them to seal. Should fix that problem. Should be done next week.

Got the heads back yesterday. He machined the cast sealing area for the valve covers. It was pretty porous and uneven. This should fix the leaking problem. Just need to blow them apart and clean them really well.

I was taking the heads apart to clean them and found 2 more tight exhaust valves with the same galling. I talked to my engine builder buddy and he thinks that the cheap valves I bought for it weren't hardened properly. So, now I'm looking for a set of SS valves. He also talked me into porting the bowls while they are apart. They will be getting 2.08 intakes but the bigger 1.74 exhaust valves.

While I'm waiting for the new valves, I decided to do some pocket porting on the exhaust. Opening the bowls should help quite a bit. Was able to conservatively open them up 0.100". Also the exhaust manifold ports were way off on the outer cylinders so I fixed that too.

New valves arrived. Unfortunately when I tried lapping the exhaust valves they didn't seat correctly. The China valves I bought befor this had a wide seat margin where these are about half. Turns out the head shop didn't cut new seats for the larger exhaust valves. Looks like they are going to need to be machined so the new ones fit. I'll take them to another shop that is closer.

When the shop rebuilt the heads they put .029" spacers under all of the springs. When I measure the installed spring height (without the spacer), I'm getting 1.86" with calipers. From what I've read, this is the bottom of spec.

I put a dial indicator on the cam to check lift and got .288". With the rocker ratio being 1.5:1, that should give me .432" max lift.

I put one of my springs in a vice and compressed it until it was almost bound up. That measurement was 1.325".

If you take the installed spring height 1.86" and subtract the max lift .432" that gives you a compressed spring height of 1.428". If you subtract the spacer they had in there you get a new compressed spring height of 1.399". Is that enough extra room to keep from messing something up? It's only about .074"? Do I need to have a spacer on the spring seat at all?

Man, you are really having some bad luck with those heads. I think. 060" is minimum coil bind clearance. So without your shims you'll be OK, but with them in you'll be too tight. Keep in mind... your 1.5 ratio might not be a true 1.5.

Damn if it isn't one thing it is another. As 440 Offroader pointed out, if you are using stock rocker arms it is unlikely you have a true 1.5 ratio. That still does not excuse the slop work that has been done. I learned the hard way on a set of small block "x" heads that you have to be very careful with choosing a machine shop. Problem that most of us will learn the hard way unfortunately because we don't build engines every day.

Since the exhaust seats needed to be cut to the larger size I went ahead and opened the pockets up to the larger size. About 1.5 more hours of work should pay off! Also touched up the intake pocket to smooth out the transition of the inside seat cut.

Fired right up!
https://youtu.be/Z1DJrGoju5w

Engine is back together. Bench bled the master cyl and installed it. Tried to bleed the brakes but the rear line is clogged somewhere. Pulled the bed off so I can finish drilling the the rear shackle mounts and fix the fuel sending unit wire (chewed by rodents). The inside frame rail was packed with dirt so I dropped the tank to clean it out and fix the wire and brake line.

These trucks look awesome with a Dana under them.
just picked up a SRT 10 Dana, for my 03 Project.
Have a Dana under the 75 D100 and the Lil Red 440 swap .

Clog was the brake cylinders. Replaced those. Also rerouted the brakeline to the rear. Someone replaced it at some point and ran it outside the rail. Dirt packed in between the frame rail and the tank corroded the original. Cleaned all of that out as well as the gas tank.

Fixed the fuel sending unit wire and the gauge still isn't working. I'll have to track that down. Could be the gauge. Sending unit was working.