Block to the machinist

Now that we have gotten christmas and new year out of the way, it’s time to get back to business. I finally took the block and pistons to the machinist yesterday. They will check the block for cracks and make sure the decks are straight. And of course overbore the cylinders if everything is OK. I’ll be reusing the connecting rods so they will check them too and swap them to the new pistons. Work should begin next week so I still have a few days for other stuff.

Eating and drinking too much is not the only thing I’ve been doing during last weeks. I have spent many nights cleaning and scrubbing and sanding and painting the smaller parts of the engine and the engine bay. I still need to paint the heads and the block itself but most of the other pieces are done.

Some of the painted engine parts

Cleaning the engine bay has been a real pain in the ass to do. Not that surprisingly, it had gathered a lot of oil and dirt during the last decades so getting everything clean takes a lot of elbow grease. I still have some more preparing to do before paint so I’ll post more later.

Comp Cams XE250H Camshaft

I happened to find a Comp Cams XE250H camshaft on sale in FMOC forum and decided to buy it. It had been installed in an engine but had not been ran so it was basically new. According to Comp Cams webpage, it offers "very strong torque, excellent mileage, smooth idle". Sounds good so I compared the specs a bit.

Parameter	Original	XE250H
Intake duration	266	250
Exhaust duration	244	260
Intake duration @ 0.050"	198	206
Exhaust duration @ 0.050"	198	212
Intake valve lobe lift	0.2303"	0.289"
Exhaust valve lobe lift	0.2375"	0.296"

I found the original cam specs from an online discussion so I'm not sure how accurate they are.

The XE250H seems to have more lift and duration when compared to the original but it is still a really tame camshaft that will probably run out of steam at about 5000 RPM. Oh well, my engine probably will not see those RPMs often so it should be fine. Especially with original intake, heads and exhaust. We'll see when the engine runs next time...

Block And Head Inspection

I drove to a machine shop in Mäntsälä with my block and heads to have them checked. They took a quick measurement of the cylinders and said that they had as much as 0.016 to 0.018 inches of wear. Way too much to be fixed by just honing. The block must be bored and I'll have to get new pistons.

My heads were a bit better. The machinist said that the valve guides were not too worn yet and the heads did not need a complete rebuild. I'll have to decide if I'll use them or the other, already rebuild heads I have.

Now I would have to get the pistons before the block could be bored. The machine shop did not have time to work with my parts before January anyway so I had a few weeks to buy them. After a few calls I was suggested to order Sealed Power hypereutectic pistons and moly rings as I was not building an engine with high power level. They were 0.030 inches oversized and should easily be strong enough.

One bad thing with them was the large valve reliefs. They would drop the compression ratio a bit. Maybe about half point from the original 9.8:1. I'll know the final ratio when the bottom end is back together.

Disassembling The Engine Part 4

My engine disassembly is finally finished. I removed everything from the block while it was still in the car. Including pistons. They came out quite easily by wiggling them a bit. The steps in the cylinder walls were so small that the piston rings came over them without problems. Finally I bolted some chains to the block and my friend came over and we lifted it out.

I'll take the block and heads to a machine shop next week. We also removed two valves to see how they looked. They wiggled slightly in the guide but I'm not experienced enough to say if that was too much. I'll have to ask what the machinist thinks. While waiting to get my parts back, I think I'll have enough to do with the engine bay. I'll clean and paint it before putting the engine back in.

Rebuilding my Autolite 4100 carb also took a couple of nights. I cleaned it as much as possible and used a Hygrade kit to replace seals, needles, seats and accelerator pump parts. The carburetor was completely covered with black dirt so I used a lot of cleaner and tooth brushes on it. I did get most of the crud off and, while not like new, it is much better now.

Disassembling The Engine Part 3

Yeah, as the replacement engine turned out to be in even worse condition than my original, I decided to bite the bullet and restore the original motor now. That meant tearing it down. I had the Mustang moved to the rented garage and got to work.

A few hours later I had removed the intake manifold and pulled the heads. Things looked pretty good inside the engine.

I could feel a slight ridge in the cylinder walls with tip of my fingers but they did not catch my nail when running it across them. I'm really hoping it can be removed without overboring the cylinders as that would mean getting new pistons. Well, I'll take the block to a machinist and ask what can be done.

New Engine? More Like New Turd

After getting the engine to a stand, it was easy to start the investigation. I cleaned it a bit and removed the oil pan. I was greeted with this sight.

The pan and oil pump pickup were covered in brown sludge and pieces of hard plastic. I tried finding the source of the plastic and the best explanation was perhaps the valve seals. I checked them and the rubber seals were there but I'm not sure if they should contain plastic too.

It was not looking good but perhaps at least the bearings would be better. They weren't. I only opened two main caps and had seen enough. Here's bearing number two.

It's also possible to see the camshaft in the background. Many of its lobes are unhealthy orange in color. Just to be sure, I also checked the bearing number 4.

Yeaaah, the bearings are worse than in my own original engine. Final nail to the coffin were the spark plugs. Two of them seemed pretty oily so either the valve seals or piston rings had been leaking.

There's no sense in putting this engine to my car so I guess I'll sell its good pieces to someone and use the money to fix my original engine. It will probably take most of the winter so I'm not sure if I can drive the car next summer after all...

New Engine

While investigating my engine I came to the conclusion that just throwing new bearings in it would probably not help much. The piston rings, valves, valve springs, camshaft and everything else is most likely also 47 years old and in need of some TLC. A complete rebuild would take the whole winter and not to mention all my money. So, I needed another option.

A possible solution appeared to FMOC forum in the form of a 302 engine sales ad. It was a 69 block with 289 heads and all accessories. The ad said that it was in good condition and the price was right so I reserved it. A couple of day later I drove over to check it out.

The seller had not driven with the engine himself but said that it had been in a car when he bought it. Previous owner had been using it a lot and it seemed fine then. I took a risk and bought it hoping I could clean it up and put it in my car temporarily. This way I would have time to fix the rest of the car and drive next summer. I'll rebuild the original engine later and put it back.

While at it, I realized that doing this engine work in my cold and damp garage was guaranteed to cause problems. FMOC forum came to the rescue again as I found a warm garage for rent a couple of kilometers from my home. I checked it out and took it for the winter. Hopefully I won't have to move there completely to get the car back to running condition in the following months...

First I will investigate my new engine a bit so I can trust it to run next summer. I think I'll open the oil pan and check the bottom end for wear. If everything seems good, I'll just clean and paint it and lift it in my Mustang. Let's hope I won't find any surprises...