The MGA With An Attitude
MGA Guru Is GOING MOBILE - (March 16 - March 31, 2021)
Tuesday March 16, 2021:
Seems like I won a trivia contest at last nights CMGC Zoom meeting. The prize was "Classic Motorsports Glovebox Companion". I think it is a 36-page booklet, and I do have a scanned PDF copy that I may post on line (if it is not a copyright problem). Meanwhile, I asked them to donate the print copy to the club library.
 A question about dimensions of clutch alignment pins fitting into the MGA-MGB flywheel may need a revision on a web page.
Wednesday March 17, 2021:
Found another source for long neck coolant recovery pressure cap for original MGA radiator, and added the part number to the web page.
Found another source for bronze thrust washers for the side gears in the MGA and MGB differentials. Need to verify actual thickness of the parts before I can post it on the web site.
Thursday March 18, 2021:
More research on length of control cables, may lead to one or more new tech pages. Added a few photos and notes to a tech page for repair of the (three) SPST pull switches for the MGA dash. Added a few new pictures to tech pages for purchased body panels for MGA body sills, doglegs and lower front fender repair panels.
Friday March 19, 2021:
At least one more trip to Tech Central to see what the guys may be up to. The MGB cylinder head porting was finished, and just getting any trash blown out of all the cavities.
Since the two year restoration of the MG Midget was finished, the owner of that car has moved on to another pet project, assembly of an Excalibur kit car (inspired by 1928 Mercedes-Benz SSK). Don't get too excited, as this one is about 30 years old and was never finished. Furthermore, it is based on the drive train and chassis parts of a Chevy Chevette. It is intended to be cute, but not particularly fast.
The Fiberglas body is still in white gel coat, hardly touched yet. The mechanical chassis is nearly complete, and he was starting to install a new aluminum radiator. I didn't know any Chevette ever had an adjustable steering column, but this one did. It also had air conditioning, but I don't think those parts will go into the Excalibur.
in a few hours much of the radiator mount was resolved. Looks like they found some Unistrut channel, 1-3/4" by 3-1/2", cut the narrow flanges off, and intended to line it with firm foam rubber.
But the star of the show today was the MG ZB Magnette Varitone. When we arrived at 10-am the radiator, engine, gearbox and propshaft were already out of the car (don't know when that happened).
The Magnette gearbox cross member was sitting net to the MGB cross member cor consideration on how to cut and weld to adapt that part. The replacement MGB 1800 engine with late model 4-synchro overdrive gearbox was also placed side by side with the original 1500 4-speed 3-synchro gearbox for dimensional comparison. Biggest issue here is the MGB shift lever is about 3-1/2 inches farther back than the Magnette shifter.
Photo here shows the tunnel top from inside the Magnette, with exhaust pipe on the ground below. The tunnel space in this uni-body sedan is significantly larger than the tunnel in my MGA.
For sure the MGB shift extension is going to be a problem. If they were to cut and weld to shorten the shift housing by 3-1/2 inches, the bottom of the bell-crank lever would end up smack on top of the overdrive unit with a lot of interference. Trying to shim the shift housing upward about 3/4 inch would result in some untenable problems getting the mechanism underneath it to work again. Then it was time to shove the power unit into the car to see how things actually fit.
With engine mounts aligned, the crank pulley with harmonic balancer was nearly touching the cross frame, so not enough room to R&R a fan belt. To avoid cut and weld of the frame, they may change the crank pulley to the original narrow sheet metal type. The engine sits much farther forward in the Magnette than it would in the sports cars, so there is plenty of space around the engine. The tubular exhaust headers are an off the shelf aftermarket part. Yes, someone actually makes that part for this application.
The shift extension hit the tunnel, so we pulled the lump out to remove the shifter, and then shoved it back in again. Then the overdrive unit was directly under the original Magnette shifter location. The top fill oil dipstick came out exactly the same as the Magnette part, so no problem there.
I was amazed how well the late model MGB overdrive gearbox fit right up inside the Magnette tunnel. Looks like no tunnel side bashing or cutting will be required.
Next was a bit of cutting to extract part of the MGB tunnel top to extend the Magnette tunnel upward a bit, and to get the shifter opening in a more desirable location.
Then a little more care when cutting the Magnette tunnel around the MGB shifter area. Drop the gearbox slightly, put the shift extension back in place, and bring the works up against underside of the tunnel. Now thinking about a little more cutting rearward to install the MGB shift lever without modifying the extension housing, and maybe just bend the lever forward for reasonable location of the shift knob. Might want to shorten the hand brake lever an inch or so, but wait to see how it fits. The engine oil pan was also sitting on top of the steering rack with engine mounts about a half inch too high to mate properly. So the oil pan adapter ring being 1/4 inch thick is not helping there. Will likely end up shimming up the engine mounts.
Things may be moving too fast, so take a break for some thinking spell. Enough for one day anyway, so clean up and put the toys away, and get back to this again later.
Saturday March 20, 2021:
Added a tech page for Weber carburetor conversion kit installation guide (1.5-MB pdf).
Updated a tech page for Single Pole Switch Anatomy with more photos and notes for the switch repair.
Added a page for the single pole dash switch in the new MGA Part Numbers Index.
Added a 8.9-MB pdf article for Smiths Radiomobile radios for MGA 1955-1963, company history plus photos and description of 20 different models.
Sunday March 21, 2021:
Some questions and ideas for a front license plate bracket that could be high mount to avoid parking curbs and articulated to allow use of the starting handle (hand crank).
Someone with a strange ignition problem, engine won't stop running when switched off, and the switch is good. This one may take a while to figure out.
Monday March 22, 2021:
More reports of faulty stretchy rebound straps. Looks like the faulty ones are now selling for ridiculously low prices to liquidate inventory, but don't be fooled into thinking some may be good just because the asking price is still higher. Currently I think any rebound strap with rubber outer covering will be faulty, as I have not heard of a good one for at least the past 15 years. I'd say stick with the web straps until all of the rubber ones are out of inventory (which may still be a long time to come).
Technical Zoom meeting with John Twist of UML, Ltd tonight. We had up to 182 people on line for the 2-1/2 hour session, all good stuff.
Tuesday March 23, 2021:
Posted a new tech page for the MGA gearbox shift interlock arm.
Posted a new tech page for restoring the factory aluminum hardtop.
Posted a new tech page for restoring aluminum side curtains for the factory aluminum hardtop.
Wednesday March 24, 2021:
Added some pictures to a web page for Electric Power Steering for the MGA.
Added a neat tip for protecting your paint during engine R&R: Pipe Insulation.
In the evening there was another Zoom meeting with the CMGC web site committee. This one went a little better. After I had to crawled all over management for being obstructive, I was finally given access to the 14 surveys that were returned (from email canvassing 200+ club members). I will review this information later. Then the committee (the few people involved here) finally conceded enough patience to listen to reason and discuss the contents and structure of the web site, who should hold the keys to the city (for security reasons), who is currently the back up webmaster. Also how many people should be involved in access to modify parts of the web site, how access can be limited to selected sub-sections for each person involved, and how much of the daily update process might be partly automated (or if automation is not worth the time or expense).
So far they haven't actually committed to doing anything constructive, other than express a wish that it might be nice to be able to accept on-line payment for membership dues for new members and renewals (but not actually allowing it to be done yet). That would logically lead to on-line regalia sales and registrations for upcoming events, like the annual swap meet vendors, holiday party reservations, or anything else for which the club accepts payments. At least there is now the possibility for a little optimism.
Thursday March 25, 2021:
Half the day was spent composing a new tech page (with some nice pictures) for someone's first hand experience installing the Vitesse 5-speed gearbox in MGA. That was the prototype with lots of teething problems, most of which should have been resolved by now for the commercial sales kit.
Friday March 26, 2021:
A funny thing happened on the way to Forum. We had a breakfast visitor this morning. An Austin Healey 3000
pulled in blowing a little steam. After a bit of cool down time he followed us less than a mile to Tech Central. This car has an auxiliary electric water pump, and an electric pusher fan, with the original belt driven fan having been removed. That might be okay, as long as the electrical stuff works. In this case a terminal screw had fallen out of the manual control switch under the dash leaving the aux water pump and fan dead. Not long to fix that problem.
 There was a green TR 250 with dual Stromberg carburetors running a little rich, idling too fast, with low power on throttle. This had a couple of issues, most of which was ignition timing being badly retarded (like 20d BTDC max at road speed, should be 32). Easy to fix the timing, and a disconnected vacuum hose.
There was another plumbing issue we didn't get sorted yet, being the funny "T" fitting (that shouldn't be there) in the hose for the PCV valve. As is, there is only one breather connection on the valve cover, with the properly restricted air cleaner connection hose going right into the PCV valve. That means the fresh inlet air goes through the valve into the intake manifold without passing through the crankcase. In other words, there is crankcase pressure relief, but no crankcase ventilation. No one had a PCV diagram handy, so we left it that way for now. It runs okay, so the driver had a smile on the way out.
The was also a red chrome bumper MGB that had a similar crankcase ventilation error. It had an auxiliary vent on the side of the rocker cover, an auxiliary side vent through a bored hole on the off side of the crankcase (not in the front tappet cover), a "T" fitting vent in top of the valve cover, and an in-line PCV valve in the hose on the way to the air cleaner. In short, three crankcase vents all exposed to atmospheric pressure, so no crankcase vacuum, meaning no fresh air introduced to the crankcase. If the little PCV valve does anything at all, it may keep oil fumes out of the air filter. There was a long discussion about this one, and he will need to get some parts before we can set it right. But for now it still runs okay without crankcase ventilation.
There was a green rubber bumper MGB that had been converted to dual carburetors with no catalytic converter,
no air pump, and an alloy valve cover. It may actually have fuel vapor recovery and anti-run-on still connected, but pretty sure the crankcase ventilation has been defeated on this one too. Not enough time to finish checking this one over, so will keep it in mind to catch him again later.
The MGB door now rust repaired and green again was being reassembled. There was another red rubber bumper MGB just here to visit today, sitting with the Jaguar which is daily driver for the owner of the MG ZB Magnette (which is getting 1800 engine and overdrive). We were working on the gearbox rear mount. Got as far as cutting the MGB cross member into three pieces, but still need to cut all pieces shorter (to match the Magnette cross piece) before welding it back together.
For the replacement propshaft, don't know where this one came from, but it is long enough. We removed the incorrect front flange in favor of a new one of correct size. Then it is going off to a driveline shop for shortening, re-welding, and assembly of a new front U-joint.
There was a bit more work on the Excalibur kit car. Tracing wires to determine which are for windscreen wipers and washers. The new aluminum radiator is mounted in rubber lined brackets. Needing to remove power steering hoses (not to be used), and to connect up the cooling pipes for the automatic transmission, and remove the tin heat riser cover (not to be used).
After a good day with the guys, time to get back to WiFi to bring you these photos and notes.
Saturday March 27, 2021:
Some time spent trying to find a source for the screw ans tube spacer in the back of the speedometer and tachometer. It is a thin tube around a screw to make it work like a shoulder screw, slotted cheese head and a very odd thread. So far no find. Instrument parts were never listed separately in the Service Parts List.
A short chat about replacing the differential pinion seal, adjusting preload on the input bearings, and measuring backlash for the ring and pinion gears.
Report of another Faulty Replacement Part. This time a new set of pushrods with the top end ball socket notably off center. They may or may not be functional, but sure are crap quality.
Ah, we finally solved the funny ignition circuit problem from the 21st. Switch key off, and engine continues to run, while ignition warning lamp was not working. It was intermittent for a while making diagnosis difficult, but it got more consistent with time. The problem turned out to be two wires shorting together inside of the ignition lamp screw-in socket (without grounding on the housing) so back-feed current could bypass the light bulb (which would normally serve as a current limiting resistor). For proof of theory we soldered a new light bulb in series with the white wire, and the problem went away. Order up a new ignition lamp bulb socket. I haven't had that much fun with electrical diagnosis for a long time.
Sunday March 28, 2021:
Another electrical issue, no power on the green wire circuits. Turned out to be a faulty fuse that looked good but had internal disconnect, wire likely not connected at one end cap.
Another report of bad rebound straps. Once cut open, they turned out to be the worst of the worst with almost no fiber inside. These are five year old parts, no longer made, but still some in inventory. This will continue to plague us for a long time.
Monday March 29, 2021:
Spending a lot of time with someone who has a Weber downdraft carburetor, some plumbing problems, and a lot of misconceptions about how things work for vapor recovery, anti-run-on, and crankcase ventilation. This is going to take a while via remote email.
Another case of no-start without a sniff of starting fluid. Then runs, but will not restart again. Classic symptoms of stale fuel. Drained tank and added fresh fuel, but then the fuel pump runs but does not deliver fuel. "It's always something".
Tuesday March 30, 2021:
Interesting case of a dead fuse that looked good, but had a disconnect inside one cap where it wasn't visible.
Someone asking about a clacking sound in his gearbox in 1st and Reverse gears only. Must be a broken gear tooth on the straight tooth bull gear on the mainshaft. I even made a casual offer to help him rebuild the gearbox. Maybe he didn't believe my diagnosis, because the same question then appeared on the MGA forum.
Wednesday March 31, 2021:
I was considering the 13 replies from the CMGC web site survey, for what it may be worth. Having been returned with/from various different email software, lots of off control characters and tabs and line feeds and font changes made then difficult to read. So I spent some time changing them to plain text and uniform format for easier reading. Then a lot of copy and paste to make a second collated document with 13 responses under each question. That should make for some interesting discussion at the next committee meeting.
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