First day in a long time that I had more than just an hour AND the weather was warm enough to work outside, so I took full advantage of the opportunity to crack open the 140hp core engine. With all the PB Blaster penetrating oil I'm using, I'm working outside to prevent the smell from wafting up from the basement.
After much research and consideration of the advice I sought and was provided online, I decided to stop fighting with the frozen head stud nuts themselves and carefully back the effected studs out of the block. Conventional wisdom is to leave them in place as they come from the factory, but as I mentioned before, a previous owner has had the block apart and clearly had the studs out a one point to do so. As a result, I'm left with few options with them. If they come out cleanly, they can be re-installed, torqued and secured permanently using LocTite 620. If they don't come out cleanly (stripped thread in the block), then it gets more complicated. Either way I'll have the added benefit of being able to properly clean and inspect the studs.
Over the past couple of days, I've sprayed a copious amount of PB Blaster on the studs where they enter the block. Using a ratchet, I slowly and carefully backed the studs out, adding more PB Blaster as I went:
Here is a picture showing the four of six studs on this side of the engine that have the seized head nuts. This has been driving me crazy for several days trying to figure out what to do. They all backed out without issue and I shouldn't have any issues reinstalling them.... Halleluja!
I never noticed until posting this picture the beautiful rays of sunshine.... all that's missing is singing angels I guess...LOL
After I removed them, I thought it might be a good idea to identify which location each stud came from. I was going to tag each with a number, but when I was on my way to look in the shop for my masking tape, I came across this mandarin orange crate. The holes in the crate work perfectly to hold these studs until I can work on removing the nuts and cleaning them up for inspection:
The next step is to remove the push rod tubes. These are held in place with rubber o-rings and are pressed into the block at one end and the heads on the other end. It's just an interference type of fit and the dis-assembly video gives instructions for making a removal tool using a piece of round hard wall tubing that when lightly struck with a small hammer will slowly tap the tubes out of the block. You need to be very careful not to damage the tubes or the mating surfaces or this can lead to oil leaks in the future.
With all the head clamping hardware removed, the heads are only sitting loose on the remaining studs. Because this core has already been taken apart, everything is only loosely together. Looking underneath, one of the push rod tubes was already hanging loose from the block. I suspect the o-rings are so dried out they have shrunk, leaving them really loose. So I was able to pull them out of the block relatively easy by just tugging on them:
Once clear of the block, they can be pulled though the head and saved for later use in the conversion. I am really pleased about the condition of these. No dents or corrosion, perfect:
Let's pull the heads. I used more PB blaster around the cylinders and let it sit for a half hour to have some lunch.
I expected to have to tug on these or gently tap them to get them to separate from the cylinders and I got most of what I expected. One cylinder stayed with the head, one came partially out and the other stayed in the block. As I was pulling the right side head I heard a metal on metal clunk. On the front cylinder, the piston is missing and the clunk was from the connecting rod dropping down as I moved the head further away from the block:
The right side head seams pretty clean. I won't be using the heads from this engine (wrong type for conversion), but they should be good for a car rebuild. I kinda wonder if that was the original intent for this core.
Having a look inside the remaining cylinders reveals another missing piston in one and a collection of debris on top of a piston in the other. Hard to tell how long the mouse was in there, but it could have been recently as the core sat outside in our storage shed since February:
Pulling the other head had similar results. This time some of the the push rod tubes stayed in the block. I removed them later to go with the ones from the other side to be cleaned and reinstalled. No surprises on this side, pistons missing, connecting rods rusty.....
....and the master bedroom suite of the mouse-house! Like the other head, this one is in great shape too.
A gentle pull on the cylinder still attached to the block and out it came. You can also see that the studs that are still in the block aren't completely torqued down will need to come out to be cleaned and reinstalled:
The cylinder on the first side didn't come off as easy. I suspect that having the piston still seized in the bore had everything to do with that:
Spray PB Blaster and wait.... time for a cold drink.
After 10 minutes, still can't budge the cylinder or the piston. Time to start working the problem from the crankshaft end. First, remove the top cover:
.... and the Top Ventilator cover under that (sorry for the bad picture):
The almighty crankshaft, the true heart of the engine..... and rusty, perhaps salvageable, will have to wait to get it completely out of the block to be certain either way.
Considering how rusty everything was, I sprayed the connecting rod nuts with PB Blaster in anticipation of them being hard to remove. Turns out most of them could be removed by hand or light turn with a ratchet.
Using a small wooden dowel as a driver, I tapped apart the connecting rods and caps. I used the dowel to prevent damaging the exposed threads:
With the rod caps removed, the piston and cylinder came out easy:
I removed the rest of the connecting rods using the same method, leaving just the crank and camshaft (not visible from this angle) in the block. Unfortunately upon closer look, this crank as a bunch of corrosion on the connecting rod bearing surfaces near the oil passage holes:
That is a huge amount of progress for one day. Next challenge is to remove the harmonic ballancer and the rear oil cover. I'm already soaking the fasteners in PB Blaster, it's been a great help in getting this apart so far. Once they are off, I'll be working on splitting the block halves and removing the crank and cam.
Time until takeoff
Husband, father and 911 dispatcher. Long time pilot with a licence that burns a hole in my pocket where my student loan money used to be. First time aircraft builder. Looking to fly my own airplane.