A Jag-Lovers Tale

III. And Then It Got Expensive...

An anonymous knock on the front door signalled the arrival of my first shipment of Jaguar parts. As usual, the UPS driver was nowhere to be seen, just a small heavy box, looking not unlike a parcel bomb, sitting on the mat. Maybe that's why the driver made a run for it. Inside I found an assortment of rubber bits, "Metalastik" sandwiches, and yellow boxes with the dreaded name "Lucas" printed on them. The enclosed VISA slip had an obscene number printed on the bottom of it, but since I was going to be ordering only a few parts, this wasn't really a problem.

The box also contained some trim rubber for where the bumper overriders joined with the bumper. I immediately went out and replaced the hardened and cracked stuff which allowed my overriders to rattle. Twenty minutes later, I stepped back to view my work with pride.

That evening I jacked-up the front of the Jag.

Removing the front suspension is not a terribly difficult task on the Mk 1. The whole thing is held together by 13 bolts, and two flexible brake lines. In my case, only 5 or 6 of the bolts were doing anything useful. Nonetheless, I was hesitant. My most noteworthy auto repair accomplishment prior to this was the installation of a fuel-injector on a 1977 Datsun. Also, heavy things make me nervous, and as I live in an earthquake prone area, climbing under a car sitting on jack-stands did not excite me in the way I wanted to be excited. In spite of it all, I supported the front sub-frame on a jack and went about loosening or removing the 13 bolts.

I was surprised at how easily everything came apart. The thin layer of oil on the undercarriage had prevented anything from rusting, and while it was messy, the bolts came out quickly. As the sub-frame was about half way to the floor, everything stopped moving. I wiggled the sub-frame a bit, but clearly it was stuck. Inspection showed that the spline connecting the steering box to the steering column had bound, and the whole thing was hanging from the steering column. First I tried wiggling the steering column, but while the spline appeared loose, it didn't budge. My next move was to tap the outer spline with a hammer. This failing, I gave it a stout whack, with similar results.

A swift kick to one of the brake rotors provide the needed impetus, and the sub-frame dropped onto the floor jack. Unfortunately the spline was still connected. The flexible coupling at the top of the steering column had failed. My mistake was simply loosening and not removing the bolt which secures the spline. A quick review of my parts catalogs revealed that my error had cost me $50, but this was OK as I was only going to be ordering a few parts.

A few days later, Ryan Border was assessing the condition of his brake booster. The inlet to the air side of his booster was sucking air big time, and he wanted to see if that was normal (it wasn't). As a check, we decided to see what my booster did. My report of this incident to the Jag-Lovers list was as follows:

Greetings Jagnuts

I am looking for happy news. I'm not expecting to get any.

This afternoon I took fellow subscriber and Mk 1 owner Ryan Border on a "How is ????? supposed to look?" tour of my recently purchased Mk 1 3.4. He was interested in the vacuum connections to the brake servo. As the car is fairly original and complete, I thought it might help.

In an attempt to assess the vacuum level in the line leading to the brake servo air filter we started the engine. To my great annoyance, clouds of smoke began billowing from the crankcase breather.

A little history...
The PO had attached a tube from the breather to the intake hose for the carburetors. On all of my previous operations of the engine, the tube had been attached. While dropping the suspension for bushing and mount replacement, I had removed the tube for better access to the steering box/steering column spline. It had not been re-attached.

Likely causes (of billowing smoke):
1. Holed piston face.
2. Broken/missing piston ring.
3. Something worse than either of the above.

When I speak of happy news, I am looking for:
1. An even more likely cause which will not cost nearly so much to fix.
2. An offer of a free installed 3.4L motor (recently rebuilt).
3. A cheap solution other than "put the tube back on the breather."
4. A bus pass.

This evenings activities will include a compression check (something I failed to do earlier, to my shame) to determine the bum cylinder(s).

Any happy news would be greatly appreciated, especially numbers 1 through 3, although number 4 would be fully acceptable and might be more immediately useful.

The compression check verified my worst fears.

Cylinder                Compression Ratio
--------                -----------------
   6                            7.8:1
   5                            7.8:1
   4                            3.0:1
   3                            7.0:1
   2                            7.8:1
   1                            2.3:1

I would have expected that the oil wiper would have given better compression than 2.3:1. Clearly, it was time to open the engine up.

For some reason, removing the bonnet (hood, for the British impaired) was a traumatic experience for me. It did not present any real physical or mechanical difficulty. Instead, its removal was symbolic of a car which would not be going anywhere for a long time. It reminded me of all the abandoned vehicles I had seen while hiking around old mining camps, all with their hoods removed. As Ryan and I set it down in a protected corner of the garage, my visions of cruising through the mountains evaporated. The new reality of living in California as a one car (and a Volvo wagon at that) family replaced them.

Once the bonnet was out of the way, it was time to get serious. Once again I wrote to the Jag-Lovers...

Last night Ryan and I managed to lift the head from my Mk 1. It took much heaving and "ho"ing and the head was nearly dropped (by me) on the fender. It would have gone much more smoothly if I had found those last two heater hose connections.

First the good news...

There is nothing obviously wrong with the engine.

Now the bad news...

There is nothing obviously wrong with the engine.

I was hoping Bryan's suggestion, that it was mis-torqued head nuts causing a blown gasket, was correct. From inspection of the head and the block, there has been no blow-by across the gasket. Also there appear to be no oil ports between the block and the head for the exhaust gasses to enter, thereby making smoke to billow from the breather. More likely I would have lost radiator hoses and such.

I haven't turned the crank yet to look at all of the cylinder walls, but number 4 (30psig compression) seems to have no scoring of the bore. The piston is in the up position in number 1 (20psig compression) so there might still be a problem lurking there. Barring some catastrophic discovery in the head, (I believe I have left myself open to some bathroom commentary here) I think the problem is worn rings.

An then it got even worse. After pulling the oil pan, I went (grudgingly) back under the car and started pulling (pushing?) pistons. As each one came out, I was showered with bits of piston ring. In all, only 4 of 12 compression rings remained intact, two on one piston (number 6). Worse yet, portions of the broken rings wore their way through the edge of the ring groove and cut a hole in the top edge of the piston on three cylinders, exiting by way of the exhaust valves. The only consolation was that the valves and seats seemed to have survived the ordeal.

It would seem that a PFO (previous %#!@* owner) had rebuilt the engine. From the descriptions in the workshop manual the pistons should be of a long split-skirt design with two compression rings and one oil ring. The pistons I pulled were short and had a second oil (guide?) ring near the bottom. The later Mk 1 was not far different from the early Mk 2s, so it is possible that these were the original pistons. It is my contention that this PFO, or his mechanic, was cheap or lazy or both. I suspect that the engine was badly worn (from the height of the ridge at the top of the bore), and rather than straightening the bores and replacing the pistons, they simply changed the rings. If true, the constant flexing of the rings, caused by the barrel shaped cylinders, made the failure nearly inevitable.

There was some good news. I had been holding a spare 3.4L engine for Ryan in my garage, and he agreed to let me rebuild that block in place of mine, which wasn't original anyway, and would have required liners.

Next, "The First Great Lull"

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