Alright another night, a little more time to wrench on the truck.
Trying to stay focused on the engine for now.
So continued checking the main bearing clearance to give me an idea where I stand, as far as machine work I might or might not need.
For those who haven’t used it, say hello to platigauge. It’s simply a piece of plastic you but on the bearing surface, torque the bearing cap (rod or main) to spec, then unbolt it, break the handy little measuring device out and see where you stand.
All my main bearings were actually in spec.
Cut a piece of the plastigauge (Still in the paper) to fit across the journal, clean the bearing and journal off, and lay the plastigauge across the journal:
Clean off the bolts, and torque the cap back in place. Then remove the cap and use the plastigauge wrapper to measure the flattened piece of plastic:
Just a reminder, to myself as well, keep track of how the main bearing and rod caps are orientated. Normally they are stamped and you can keep them the same way, in the same place. I keep every cylinder in its own Ziploc freezer bag:
Some main bearing wear, but nothing out of sorts for 150k hard miles:
Got the oil pump out to clean it off:
There must have been a previous “repair” attempt, the oil pump screen and big long piece of blue RTV in it. There was evidence of its use on the oil pan. Nice. I threw it across the garage and couldn’t find it when I took the pics:
Loosen then take off the rod bolt nuts. Then take a piece of wood (personally I like the hard rubber end of a long hammer) and use a hammer to knock the cap loose by hitting the end of the rod bolt.
It’ll pop off. Then get some rod bolt covers, so the rod bolts don’t mess up the crank when you knock the piston / rod assembly out. Here’s my high tech, patent-pending version:
Then use the same wood or rubber piece to knock the piston / rod assemblies out the bottom (top actually) of the block. Use the “beefy” part of piston to “persuade”. If you have a pronounced ridge at the top of the cylinder, you may need a ridge reamer or something like that to get the pistons out.
Now I was taught this trick a long time ago, actually learned it when I was tearing down an engine where I wanted to resuse the forged pistons it had. Thread in two head bolts (opposing corners of the cylinder you’re working on. If you do it right you only have to move one bolt at a time as you move to each cylinder – kind of like the golf tee game at Cracker Barrel) then wrap the bolts in rubber bands, rope or even electrical wire (it was right near where I was working). This will actually catch the piston as it comes out.
Oh, and if you’re like me and you can’t find your crankshaft socket (to rotate the crank around to make it easier depending on which cylinder you’re working on) then make do.
Where’s that bag of flywheel bolts? That’ll work. Thread ‘em in, use a long screwdriver to rotate. That’s the ticket:
Well there’s definitely some wear on the rod bearings. I’ve seen worse, down to the copper on a few of ‘em:
Pistons don’t look bad at all, and I only broke one ring. #1 cylinder, so not sure if it was already broken
And also I ran across what looks to be a very small “nick” in the crank on one of the rod bearing journals. I know I didn’t do it, it didn’t show itself until the rod cap came loose. There’s also a small spot near the oil hole in the journal. No pics, I was a bit ticked off.
Guess I’ll have to take the crank to the machine shop for a polish or grind. We’ll see.
Oh well, it is 47+ years old.
Since I’m doing the crank, I’ll also have the rods checked out.
I’ll get a tally for parts / labor before I make a decision to rebuild it or toss it.