Jag Engine Page
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Work on the engine was a start and stop process. Initially all I wanted to do was prove to myself that it would run. I went through the fuel system, starting with the gas tank which was filled with twenty year old gasoline (YUCK). After cleaning it, replacing the fuel pump, flushing all the lines, and overhauling the carbs, I began prepping the engine for an attempt to start it. I pulled the manifold and flushed the crud from the passages as best I could. I filled the cylinders with oil and cranked the engine with the plugs out. This at least proved that the engine was not seized. Next, I changed the oil and filter and turned the engine enough that I hoped that the old oil was clear of the bearings. At that point, I gritted my teeth and gave it a try. I was pleasantly surprised to hear it catch and run. After all those years, it was a glorious sound. After several minutes of running, it settled down and even idled fairly smooth. That was enough for me.
Hummmm, I think I see the problem!!
The neighbor stopped by to give me a hand. He says he speaks the language and knows the PO.
After this, I drained the water and fuel and went on to other things.
Eventually, I returned to the engine and began by pulling the head.
First the cams and intake. This was pretty straight forward and I had done this before. Next came the chore of actually breaking the head loose from the block. Mannnn, was that thing tight. This engine has what some refer to as "wet studs". The head studs extend all the way down to the bottom of the block.
I ended up pulling the exhaust manifold as well so that I could position a bottle jack between the head and the bottom of the block. This went on for most of the afternoon, alternating sides. Each time I got a little movement I would go to the other side, chocking first to keep it from rocking back and loosing every thing that I had gained. This would have been sooo much easier with two jacks, and even better, with two people.
Finally there was success and the head was free.
Isn't it amazing how the combustion chambers aren't centered on the bore? Also note all the carbon buildup, those were the days of leaded fuel.
After cleanup, I was pleased to find the water passages in really good shape. At this point it was off to Coventry Classics for a refurbishment. There, Tom would suggest the works. New valves, springs, guides, and of course reconditioning the seats, as well as resurfacing the head. There was also another problem to be dealt with and that was the tappet guides.
Back in the day I had fought a losing battle trying to deal with the tappet guides. They would periodically work their way up until they got clipped by the cams. I tried to reseat them and stake them in place but with no luck. Tom replaced five of them and installed a hold down kit. Hopefully that will be the end of that!
I had ordered a gantry crane from Harbor Freight which took about two months to get here. When it finally came in I was ready to pull the engine and transmission. After listening to the debate on the Forum, I decided that I wanted to go out the bottom. The general consensus seemed to be that this was the best way. After doing it, I agree completely. I had pulled the engine out the top, twice before, due to clutch problems so, I have something to compare to. I will never go out the top again.
While waiting on the crane, I built a cradle for the engine/transmission assembly.
This is what it looks like bolted in place.
Once the gantry was assembled, I rolled it into place and fashioned a sling from a tow strap.
The chain hoist and gantry easily lifted the front of the car. Removing the front wheels, I lowered the front end until the engine cradle was resting on its casters.
From here, all that was left to do was disconnect the mounts and away we go.
Initially I mounted the engine on a stand that I had. We had used it successfully several times with the small blocks from my son's mustang. However, once I got the XK engine on it, I was very nervous. The engine is heavy but, more importantly, it's long. With all that overhang, I was afraid that it would overturn once I started horsin' it around.
A quick trip to Harbor freight and things were better.
The pan and the front cover came off.
And all the freeze plugs (yea, I know, they're really core plugs but, hey, I've been calling them freeze plugs too long to change now) and head studs came out. With a lot of tapping and soaking with WD-40 as well as a healthy dose of luck, I didn't break anything.
The rest of the stuff, -chains, pump, rods and pistons, and crank were removed to begin evaluation.
While the crank looked pretty good at first glance, I was saddened to find that it was out of round enough that it was going to need turning.
Same with the bores, close, but no cigar. From here it was off to the machine shop.
There it was vated, decked, and bored .020" over. The rods were resized and fitted with new pistons and pins. The crank was turned 10-10 and I had the flywheel resurfaced. Once I had everything in hand again I started with the clean up and prep work for reassembly.
From what I can understand, the cleaning solutions used today are not as strong as they use to be. I still had some rust and scale in the water jacket that I had to clean.
I cleaned the scale out of the bottom of the water jacket as best I could and chased the threads using a 7/16X20 NF tap.
Others have indicated that they had to build something special to get a tap into this area but I just used a 1/4" drive, 9/32", twelve point socket on an extension. I used a little bit of masking tape to keep the tap from falling out of the socket and all went fairly smoothly.
All the mains were checked with plastigage.
And the endplay.
I was happy to find that all was within spec.
Next came the pistons.
End gaps were checked at bottom and top of each cylinder and then installed on that piston.
And then installed into the cylinder.
And each rod bearing checked.
After the pistons and rods were installed, new head studs and stainless steel freeze plugs went in. At this point I needed to do some painting before additional components were fitted. Originally I did not intend to do any "pretty work" at this point, but realized that it would be unsatisfactory to try to paint all this engine stuff later, once the engine was assembled. I gathered some smaller items to do with the block, cleaned them, and treated with rust converter. I used PPG epoxy primer and DCC 9300 concept black urethane. It's little too shiny but will probably dull back with time and heat.
At this point it was time to move on to other things. I had ordered a chain kit consisting of upper and lower chains and all the slippers. When I began disassembling the original stuff I discovered something that seemed a bit odd. Something had migrated into the area of the sprocket bushings and shafts. As you can see, the oil holes were plugged with this material. I don't know whether it was bushing material or something else but,what ever it was, it necessitated new bushings and shafts.
At any rate, that's where I am now, waiting on back-orders.
In the mean time I filled in with a few little projects like the distributor.
After what seemed like endless delays with suppliers, I finally had the things that I needed to proceed.
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