The MGA With An Attitude
Sunday, November 1, 2020:
Bye bye to daylight savings time, no more evening outdoor tinkering sessions. Had a little chat about flasher units to support 4-way flashers. Then spent much of the day researching the screw type for securing inner wing vent panels for the Twin Cam. Ended up posting a few new pages in the MGA Part Numbers section for this screw and the related U-nut (Tinnerman fastener) and the vent panels, and revising the previous page in the Twin Cam tech section to add the latest information. Monday, November 2, 2020:  Finally not so mysterious, the correct screw is identified as Type B Self Tapping Screw, #10-16 straight thread with tapered nose and blunt tip. It has a larger root diameter and finer pitch than the common Type A pointed tapping screw (which would be #10 with 12-tpi), so the mating captive nut will also need to match the Type B thread form. -- These screws are apparently common with aircraft parts supplies, but also available from McMaster-Carr here in the States. https://www.mcmaster.com/90056A240. You wouldn't believe how much time this killed (and how many people were involved in the research). Tuesday, November 3, 2020: Election day here in the states, when the party turns into a zoo. Kind of quiet on the internet. I think lots of folks took the day off to hide. Got questions about dash sub-harness, engine oil leaks, rubber rear seal again, more about inner wing panel screws (may not have a good modern part number yet) Wednesday, November 4, 2020: Early morning, my cell phone crapped out. It says. "Insert a SIM card". The gadget seems to work locally, just can't make or receive calls for talk or text, so what good is that? Can't even call the service company, so need to find a phone store. Internet still works, so I can still do email and work on my web site. Another email chat about rubber rear seal for the crankshaft to stop a bad oil leak, which seems to be endemic with these cars. More questions about inner wing panel screws (may not have a good modern part umber yet), orientation of the distributor, orientation of the flywheel (and balancing), turned ut to be a busy day for email.  On someone's request I started to combine 10 chapters of a book into one large PDF file for the Lucas Technical Service "Overseas Correspondence Course". When it turned into more work than anticipated, I paused to ask, "Why"? Some years ago I spent a lot of time splitting it into 10 separate files to be easier to download. So I sent the guy a message to ask what his intention was, why he wanted it all in one cumbersome PDF file. Thursday, November 5, 2020: If nothing else, I got my cell phone fixed today. I asked what does "Insert a SIM card" mean, as that was showing on the front display. I suppose all the guy did was remove and reinstall the SIM card (a couple times), so maybe it was just knocked out of place or had a dirty connector. Then we went foraging in the food side of the local Walmart, and back to the cave for more isolation. Was a nice day reaching the low 70's and sunny, so good to get out for some fresh air for a change. If we keep the curtains closed and sleep and eat when we like, it gets hard to tell the difference between AM and PM without looking at a digital clock. Not much worried about COVID, but trying not to get SAD (Seasonal Affective Disorder). 
Began getting messages from Sally Irvine, daughter of Robin Irvine, supposedly first owner of PRX14, after it was released from the factory in 1962 (the factory development Coupe with notable competition history). After a few messages exchanged, this may lead to more of the early history of this car, as Robin Irvine is still with us and seems to be in the mood for some chat. And there may be some early pictures lying around (1962-1964), which with a bit of luck and persistence might eventually come back to light. Friday, November 6, 2020: More of the usual email tech questions and BBS messages. A question about threads for screws on the rag top frame cross bows, but that was just a refrral to a tech page already on the web site. Someone with an engine with low compression on one cylinder. Had the head off, no leakage past the valves, only small fluid leak-down past piston rings on one cylinder. Reassembled with now head gasket, and still 100-psi and 90-psi on two cylinders. Beginning to wonder if the valves are not adjusted properly, like zero clearance and valves not closing. --A few more messages from Sally Irvine. The story of PRX14 is getting more interesting. Saturday, November 7, 2020: 
More information from Sally Irvine about the early history (and first ex-factory owner) of MGA PRX14. The car was purchased by her father on his 21st birthday 25th September 1962 from Marshallsea Brothers in Taunton, Somerset who were the Morris MG distributors. Originally Mineral Blue with steel wheels, he paid £530 for it. Well it was fairly well used and out of production by that time. When his family began to grow, two years later he traded or sold it back to the same dealer where is was subsequently purchased by Ray Casely in 1965 for the handsome sum of £325. There was another long term owner A.F Rivers Fletcher who raced and rallied the car, subsequently changing the color to lighter blue, installing wire wheels and the MK-II grille (along with other personal touches). The car was purchased by Mike Peters in September 2009, given some needed maintenance and returned to competition. He had it stripped and repainted again in 2017. Sunday-Monday, November 8-9, 2020: In case you were curious, a factory issue cigar lighter measures 2.1-ohms resistance (someone measured it), so will draw about 6-amps at 12 volts. The engine reported earlier with high oil consumption has rebuilt head with new bronze valve guides and umbrella seals, and the valves do not leak. So after reassembly with a new head gasket, low compression on two cylinders must be down to bad rings. More questions about how to restore fabric covered side curtains. Asking the wrong guy, because I have never done it. Tuesday, November 10, 2020: Got out of the cave to go tinkering today. Dave Daniels bought ten new Nexen tires for his MGA and MG TF. his son Jay was driving the TF when the brake pedal went to the floor, and it limped home with no brakes. Pull up the carpet to put fluid in the (under floor) master cylinder, try bleeding the brakes, and it dumped fluid from the right rear wheel cylinder. Bummer. 
 We killed much of the day pulling the rear brakes apart, jolly good fun pulling brake drums off of the splined axles. We disassembled the RR wheel cylinder with a passing thought for rebuilding it, but it turned out to be one of the "modern" design that does not have rebuild parts available. So we decided just buy new ones for replacement because they are cheap these days, and buy the type that will accept the original rebuild kit. 
 While it was jacked up, crawl underneath to see where it was leaking gas under the fuel tank. Looks like the drip comes from the mounting gasket for the fuel level sender unit, so order new gaskets for that and seal washers for the fuel pipe and drain plug (just in case). 
 Put in a parts order in mid afternoon, which may or may not arrive by Friday. Pick up, pack up, clean up, and then the MGA was off off for its tire change in the evening. Wednesday, November 11, 2020: Dave's MGA is back with new tires, very nice. Three of the TF tires went in for change while the car is still jacked up in the rear. The front tires will likely wait until the rear brakes are back together. I got to work catching up 4 or 5 days worth of notes and photos. Thursday-Friday, November 12-13, 2020: Not much happening. Did some work on the MGA Part Numbers list, adding a few new pages (the idle time filler). Dave and Jay jacked up the front of the TF to remove the wheels, getting those to the tire shop to fit the new tires (now all five finished). Saturday, November 14, 2020: 
Got an early morning call from Ansel Gantt in Columbia, SC. His '72 MGB needed some attention, having been parked for a couple months, not wanting to start, and leaking fuel around the HIF carburetors. So I wandered over to see what I could do. First issue was a split pin on the choke cable link had poked a hole through the small fuel hose between the carburetors, accounting for the fuel leak. That's a new one I had never seen before. Pull the air cleaners, clip the extra length tails off of the errant cotter pin, install a new hose, and that was the end of the fuel leak. 
 With a lot of choke we got it started okay, running very rough, barely idling, obviously very rich on the rear carburetor. I backed out the mixture screw on the rear carb three turns to lean it out to correct mixture. After a bit of fine tuning it was running well, so I reinstalled the air cleaners. 
Then it would not start again. Bummer. Thinking maybe stale fuel, I gave it a shot of ether, but still no fire. Checking on the ignition revealed extremely weak spark from the coil (relatively new coil). Checking the coil I found 3-ohms resistance in the primary winding (normal for not using a ballast resistor), and about 9000-ohms in the secondary winding (also normal, not open circuit), so should be a good coil. Thinking possibly failed condenser, I removed the distributor cap to find a Pertronix ignition module, so all bets were off. A new Pertronix module for this model is by now $125, and it is out of stock, back ordered at Moss Motors, USA. We could make a phone call to see if there is a local source, but I doubt it. Looking for replacement distributor for 1972-1974 MGB, points type with vacuum advance tapped into the intake manifold rather than from carburetor venturi. Those distributors (and replacements) also not available from Moss Motors. Now thinking we may have to buy all the parts for the breaker plate assembly, points, condenser, lead wires, etc to convert the existing distributor back to points. Scratch head, consult catalogs, and maybe take this up again Monday morning when I can call Moss to see if they might have some replacement for the correct distributor. Why should 1972-1974 distributors be so hard to find? Sunday, November 15, 2020: Brake parts for the TF came in, so back over to Dave Daniel's place today. Just a little fettling to get new rear brake slave cylinders to fit, shoes and drums installed, bleed the lines. Then the parking brake cables were frozen, so put those on the shopping list. 
 
 Took a little time out to get first use out of some new tube wrenches to tighten a bezel nut on the ignition switch. Brakes were dragging on the right front, needing to remove the brake drum with hub and bearing assembly. Managed to get the drum off, but left the inboard bearing stuck on the spindle. Trip to Harbor Freight for a 6-inch 3-leg puller to remove the inboard bearing, and put it back in the hub with a new seal. Then the hose was clogged, not allowing fluid to return to the master cylinder, so put three new brake hoses on the shopping list (along with the parking brake cables). 
 Drained fuel out of the tank with intent to remove the fuel level sender unit to install new gaskets. Received incorrect fiber washer from Moss, but managed to get the drain plug sealed. Then ran out of time (and daylight) and had to re-schedule the sender unit gaskets for later. Wheels back on, all the nuts and bolts tight, topped up the maser cylinder, and got the TF out of the garage. Brakes worked okay, so Jay could drive the car home (with me following him ten miles on the expressway). Seemed like a good day's work, and we can get back to it again later. 
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