E-type upper chain adjustment

While the radiator was out of the way, which provides superior access to the front of the engine, I took advantage of the opportunity to check the upper timing chain adjustment, which is set manually.  The owner had asked us to check it as there is auditory evidence of a chain rattle on the overrun.

Adjustment gear

Because the adjustment was perfectly tight my money is on chain stretch.  The picture on the right is of the gear on the upper chain eccentric.  To adjust the chain you depress the plunger located at about eleven o’clock and turn your tool counter clockwise.

Radiator in place with Kenlowe fan

As mentioned previously the ‘direct fit’ Kenlowe fan kit proved to be anything but.  There really was no provision at all for mounting it to the radiator so Rodney at B&R’s Garage fabricated a pair of mounting straps, and much to my chagrin it would not clear the mounting bracket for the old fan motor, so I took out my spotweld cutter and took the bracket off.  But all’s well that ends well. so wiring it up and replacing a couple of hoses are all that remains.

This doesn't look good, either

Another week, another broken XPAG.  For the second time in two weeks we’re poking around inside an MG TD engine searching for the cause of a failure.  In this event the physical symptom was a severe engine knock.

As seen here, #4 connecting rod throw has the waves of heat discoloration which are consistent with a significant bearing failure.

Washers under #2 con-rod castle nuts

In the picture to the left, a close examination will reveal the presence of a pair of grade 8 SAE washers under the #2 connecting rod castle nuts.  When I pulled the bearing cap off the#4  con-rod, the bearing inserts, a +.050″ undersize,  were well and truly destroyed.

Although this might look like a riddle inside an enigma, the evidence suggests a previous catastrophic bearing failure on #2 rod journal.  In order to make chicken salad out of chicken scratch, the machinist undercut the con-rod enough to be able to machine it round again, but with so much material gone he needed to shim up castle nuts with washers in order to be able to install the cotter pins thru the castle nut slots.

Last week's failure:#4 exhaust valve, broken thru the keeper groove and saved by an o-ring

The crankshaft must have been an awful mess too, to save it the crank guy cut the rod journals .050″ undersize.  Because of the huge weight differences rod to rod a balance job would have been a good idea, but none was in evidence.  However the fatal mistake was in not reconditioning the other connecting rods at the same time.  As we now know, #4 failed soon after.  What this means is a new crankshaft and probably a pair of connecting rods as well.

So here’s a picture of last week’s TD engine failure whereby the #4 exhaust valve broke thru the keeper groove and was saved from a nasty encounter with the on-rushing piston by the foolish o-ring that was the examplar of 1950’s upper cylinder oil control.

Myron gets some new clothes

Back in the spring we made note of the fact that a formerly well known Port Washington area (Long Island) MG TD known as Myron was a going concern again.  Once running, we had to shelve the project while we waited on his fenders and running boards which were being painted a contrasting black, and once arrived, we were too deep in the weeds with other work to do anything about it.  However with the arrival of the summer help in the person of Reilly Clark we’re starting to make time on it.

The source of a growling sound in the brake assembly

Your scribe was summoned to Dorset, Vermont recently to retrieve a Triumph TR3 which was emitting an awful growl from the rear axle on the right side.  I went out the driveway with the car on my road test and turned around and came right back in because I thought it might have been the rear wheel bearings signaling their demise.  Unlike MG’s & Austin Healeys, Triumph (& Jaguar) rear wheel bearings are not lubricated by the gear oil in the rear axle.

Rodney at B&R's Garage looks over a 'direct fit' E-type fan kit

They are instead packed with grease and protected against the infusion of the diff. lube by an oil seal, and therefore can suffer the consequences of 50 years of neglect.  A brake lining broken away from the shoe was the culprit.

Earlier this week we ordered in a Kenlowe fan kit to replace the two blade windmill in another series 1 E-type.  Despite assurances that it was a “direct fit” kit, it wasn’t.  After looking over the universal mounting system supplied with it I decided that what I really needed was a direct consultation with Rodney at B&R’s Garage, the best radiator man in the Northeast.

After the Deluge

So I loaded up my MG and headed up to Lebanon, N.H. quite unaware that a severe thunderstorm was headed down.  As I crested a hill just south of White River Junction, Vermont I saw a veritable wall of water coming at me.  It is a fact that after 25 years MGB ownership I can put the top up in less than 30 seconds when well motivated.

It is also a fact that several years ago when Rodney first sent me to Dave’s Starter & Alternator Service, also of Lebanon, Dave had a rewound armature for an Austin Healey 3000 generator on the shelf.  All of our rotating electrical has gone there ever since.  Unfortunately for them the same storm that caused me to put my top up also brought their big tree down, so while-you-wait service was unavailable Wednesday afternoon at Dave’s.

For Sale: TC8600 Uprated engine with Laystall Head (by Us). Inquire

Monday morning 8:00 am

Every 50 years or so the three HD8 carburetors on a series one E-type need some attention.  We have previously paid attention to a somewhat precarious radius arm mounting  with good result, and having adjudged the car good to go, we returned it to the owner for whom the drivability immediately went south.

A series 2 recovered Saturday night

So back it came, and after a frazzling day of carburetion & ignition Butch has it about dialed back in.  We think.

In a somewhat uneven exchange I trailered out an MGB Saturday afternoon and returned with a series 2 E-type which is alleged to have an electrical draw which flattens the battery, although my armchair hypothesis is not enough use.  I put a new Interstate battery in it Saturday night to get it going and I’ve been monitoring & recording the voltage on a daily basis until we can get properly to work on it…

This doesn't look good

…The owner of the TD complained of a sudden loss of power so we had Rods Towing & Repair of Putney drag it in.  First I checked the point gap, of which there was very little. and then I popped the carburetor float chamber covers off and the rear float was  nearly submerged, meaning the engine had been running  hopelessly rich.

But it was a compression test which ultimately told the tale:  the first three cylinders had respectable compression but the fourth one had none, as in zero.  This is a very lucky car (and owner) because the #4 exhaust valve broke across the keeper groove and somehow the o-ring used for oil control managed to prevent what was left from crashing thru the piston.  Note the valve spring closest to the battery.  More on this next week with pictures.

Spaghetti Junction

Meanwhile Reilly has been sorting thru a TR6 from Branford, Connecticut.  Replacing the fuel pump has the car running much better now and changing out the non-functioning rear shock absorbers and replacing the differential mounts has really squared away the back of the car, although an improvement of almost equal magnitude was acheived by tightening up the 16 bolts on the half shaft universal joints as well as the rear bolts on the driveshaft.

In the interest of searching for a more pregressive clutch, at my direction Reilly hauled out the transmisison for a look around.  Not much was found, with the possible exception of this colorful rat’s nest of radio wires.  Why anyone needs a sound system in a sports car with that most melodious of engines, the in-line six cylinder, is beyond me.

Thursday afternoon at the TD exchange, we swap a red one for a brown one

'76 MGB in its original Bracken livery

Our neighbor Norm Wright found this 1976 MGB in Manchester, Vermont, still resplendid in its original bracken paint, but needing a clutch, tires  and some other titivation.  Speaking strictly personally, I’m kind of partial to some of the colors seemingly left by the wayside such as this car displays, like, say any MGA still wearing, or at least close to, it’s original Alamo Beige.  Most recently, we changed out the brake master cylinder, and hey, it goes pretty good.

Master cylinder extraction

Master cylinder installation

Later MGB master cylinders with their PDWA switch and three brake lines can be kind of a fiddly installation, and creating good access makes the job much easier.  ALWAYS start the brake lines by hand before using a wrench.  We begin with the one on the bottom before we even slide it over the brake servo studs, and use Vice Grips GENTLY to help line up the other two pipes.  If you’re not sure about whether the servo has turned into a brake fluid sump for a leaky master cylinder, undo the vacuum line from the manifold and use it as a putative drain pipe.

Take special note of the wet paper towel (brake fluid is the solvent for paint, and water the solvent for brake fluid) and the fluorescent drop light which can’t become an ignition source for the fuel in the carburetor.

What's wrong with this picture ?

In other MGB news, Reilly has been sorting thru some diverse issues with a 1972 MGB of generally good character.  One of the items for attention was tracing the source of a very hot fuse protecting functions which are switched thru the ignition like the wipers & turn signals.  We call it the “green” fuse.

The first obvious fault was the installation of a 35 amp Parts Store fuse.  The correct Lucas-style fuse allows a 35 amp surge, but only 17 amps continuously, (17/35).  However the ultimate culprit, pictured above, was in the trunk.  A black wire (always ground) plugged into the snap connector for the brake lights, which are of course green wires and therefore hot when the brake light switch is on.

It's 2014. when were your wheel bearings serviced ?

Sticking calipers were another complaint.  Dealing with calipers is made a whole lot easier if you first remove the brake pads and then pump the pistons out against the brake rotors.  Sometimes they’ll pull out at that point, but when they don’t we center drill & tap the pistons and use a hex bolt as an extractor.

It’s also considered to be good etiquette to clean & repack the front wheel bearings at the same time.  We’re guessing these wheel bearings were last serviced some time around 1980.

This MGB is due back in Washington, Vermont this weekend, and from there we’re off to Stowe to recover a very spanky series 2 E-type.  Stay tuned.