The MGA With An Attitude
MGA Guru Is GOING MOBILE - (December 1 - December 15, 2017)
Friday December 1, 2017:
Goodbye to Jacksonville at 6:30-pm last night, and drive past midnight. This morning we are 350 miles southwest in Bonita Springs, Florida, back to visit some old friends at Tech Central Racing. Never sure what we may find here, but almost always some folks working on MGs and other vintage British cars, providing toys to tinker. They meet on Fridays, and sometimes (often) Saturdays (when the guys are not racing). The derelict race car is about to be resurrected to be put back in racing service. The Spridget hiding behind the tool chest has a freshly rebuilt engine and is getting through a slow restoration. The Ford Ranger has the seized gearbox out for repair (think it's someone's tow vehicle). The MGA under the tarp was recipient of a freshly rebuilt 1800 engine last time we were here in January and early February, but looks like it has not progressed much since. That one belongs to Headley Wilson from Fort Myers.
Headley showed up late in the day to strip paint from some non-British engine parts (a treat for his daughter). Notice the Mazda RX7 carrying an honorary British flag license plate, still a functional race car. The Midget in back is perhaps the resident daily driver car. The blue MGB was in for some minor work, but the job seems to be temporarily stalled.
The silver MGB was running lame with a stuck choke on the rear carburetor. This turned out to be the fault of a broken torsion spring for the rear choke return mechanism. We didn't get the spring replaced, but I did manage to add an auxiliary tension spring and otherwise jury rig the choke linkage to get it back in service. Oddly, it has three electric fans. One runs the right direction but has the fan blade on backward (easily to fix later). The second one does not run, the wires being hidden behind the grill for lack of access, and no time to sort that out. The auxiliary fan in back seems to run in concert with the original fan that does run, and it is reported not to overheat, so the owner was happy to continue driving it as-is. The red MGB in the background was running extremely rich, nothing physically wrong with it, just needed some gross fuel mixture adjustment to be happy again.
The Triumph GT6 Plus and the TVR were in for minor service, while the Sunbeam (Tiger I suppose) was in the midst of full restoration. Nothing to do with any of these cars today.
Not everything that glitters is British. Pretty sure that's an Alfa Romeo being neglected in back. The Nissan sport-ute got a new battery before day's end. The vintage pressure washer with no engine compression and seized spark plug was relegated to be scrapped.
This morning I had in mind to do some rather serious work on my MGA, but things were more pressing with other cars, so mine will wait for tomorrow.
Saturday December 2, 2017:
Back at Tech Central today, determined to do a little overdue maintenance on our MGA engine. For some time the car has had a rough idle at anything below about 1200 rpm, and has been somewhat hard to start in the morning. A couple weeks ago a compression test showed 125, 110, 90, 75, so it was time to do something about it, and the head had to come off for a little touch up. I could have done blow down test to see where it was leaking (which valves), but with those low compression numbers we knew the head needed attention anyway, so skip the blow down time. Good fortune, no one else showed up today, so we had uninterrupted service time. 10:00am start, drain the coolant remove the cylinder head, turn it upside down, and fill the combustion chambers with water to see what leaks, and leak it did.
Almost a surprise that exhaust valves were sealed tight. Intake valves were leaking pretty much in line with the low compression numbers. In about five minutes #3 chamber was empty, #4 half down, and #2 down a little bit, and #1 seemed to be not leaking at all. So we figured to touch up three intake valves, and not touch the rest. Easy to see the dribbling water with a flash light. Tough trying to take a picture inside the intake ports, but here's the best of the bad pictures.
 Okay, out with the spring compressor, off with the springs and seals, but only one valve at a time please. The white edge of the valve in the picture is the (clean) vertical outer edge of the valve head. The black streak next to it is a bit of carbon on the valve seating surface. The thick carbon deposits near the valve stem are result of long term oil leaking down the valve guides for 30,000 miles since a couple of valves were touched up last April, or 65,000 miles since the rebuilt head was installed a year and a half ago.
Carbon on the valve seating surface may result from the seat being too wide, resulting in too little surface pressure. But in this case there are not so many miles on this head, and the seats are not worn too wide, so that was a bit of a mystery. It didn't take long to wire wheel the valve clean, then do a little touch up with lapping compound and the suction cup stick lapping tool. That took the carbon off and cleaned up the valve head in short order. But the valve seat was a worse story. What we found was apparently a pear shape to the valve seat where it was not touching the valve head in about a 90-degree arc near the exhaust valve. Best guess is this is a result of clean surface in the hotter zone combined with carbon deposits rest of the way around, resulting in compression leak in the clean area eroding the seat. In any case, that was not going to clean up with hand lapping, so on to Plan B. Put some sticky sandpaper on the vave head, oil the stem, drop it into the head, and give it a spin with a power drill to "grind" the valve seat. Aside from taking somewhat longer thtn expected, this works, so eventually the seat cleaned up enough to seal with just a little hand lapping.
In the process we found one of the umbrella seals popped up out of place, and another one disintegrated, which could account for some of the oil deposits. I did have new valve seals in the magic trailer. Having cleaned up the three intake valves we knew were leaking, we did another water test, at which time we found #1 intake valve to be leaking as well. Bummer. But by now we had a handle on the job, so just R&R the 4th valve for similar treatment, and eventually we had no leakers, and I am quite happy that we did all four intake valves, so may not need to bugger with it again any time soon.
Tough day, but we did get it back together a little after dark working with flash lights to install the carburetors and linkages and top up the coolant. Ran it long enough to get good running temperature, and re-torqued the cylinder head. Replaced rubber grommets on the valve cover nuts, but still need to replace the cover gasket, sometime. Cleaned up, tools stowed, locked up and off to dinner by 8-pm. It feels good to be done with that little chore, but remember, it's just maintenance.
Sunday December 3, 2017:
Recovering from yesterday's PITA cylinder head work. Good to relax a bit while catching up communications.
Monday December 4, 2017:
Good thing we didn't have anything scheduled today. Spent nearly the whole day reformatting the monthly CMGC newsletter for the club web site (and not quite finished).
Tuesday December 5, 2017:
Finished conversion and uploading of the club newsletter. If anyone was interested, see here: http://ChicagolandMGclub.com/driveline/current
Time to fire off about 40 emails to see who in Florida wants to play these days.
Wednesday December 6, 2017:
Most of the day spent building a new tech page for the vinyl covered wooden door cap for MGA Coupe, complete with photos and drawings with dimensions. Not everything is rush, rush. Sometimes I get to sit to work.
Thursday December 7, 2017:
After morning email and a few tech questions, we tried to get an oil change at the Walmart superstore in Bradenton, FL. After a tyical two hour wait in early afternoon, we were informed that they refused to do it. Not the first time this has happened, but fairly rare. The official excuse is that they don't have a torque spec for the oil drain plug. Not that it bothers me to much, but I would like to know the real reason. Being a bit ticked for a couple of reasons, we just headed south for tomorrow's hook up.
Friday December 8, 2017:
Back to Tech Central in Bonita Springs, FL. The significant pet project today was an MG Midget with a good start on restoration. Engine had been overhauled, reassembled, and was sitting in fresh paint. Now the gearbox was up for touch up. Side cover off for internal inspection revealed apparently good mechanical parts including good synchronizers. History of the unit was not known, but no reason to suspect there might be anything bad, so it was elected not to disassemble it. Clean it up some, reinstall the side cover, install a new rear seal and rubber mounts.
These was a pretty blue MGB that was recently purchased for a song, easily made roadable, and now thinking about how to fix a few minor things without spending too much money. Interference between boot lid edge and lower body with chipped paint looked like the fuel filler cap was bashed in from behind, deforming sheet metal slightly inward and upward. A new weather seal might reduce the interference. Meanwhile someone came up with a new grille badge to replace a missing part.
After a quick lunch and a short cool down (the car, not me) I did a compression test on the MGA to check on the results of last week's valve touch-up work.
All is well here with four compression numbers between 127 and 134. I'll take it. Then use the set-back timing light to re-adjust ignition timing to 32d BTDC at road speed (no vacuum). That was a good move, because it had been running with too much advance for some time (implied by hard to crank when starting and rough idle when hot).
When the crowd broke up we headed back north to visit Headley Wilson in Fort Myers. His MGA was procured in boxes, and he has been reassembling it for quite some time. This evening we fiddled with a door for a while to get acceptable alignment. It was enough for one day.
Saturday December 9, 2017:
Today's task was to get the master cylinder installed. Easier said than done when it has been disassembled forever, some parts missing, and needing to make up a hydraulic pipe for connection. The master cylinder had already been rebuilt. Local auto parts store provided a short brake pipe and threaded union. The magic trailer anted up a threading die, Dremel tool, and some copper washers to seal the banjo bolt. Too bad we couldn't find the pushrods immediately, but some progress is better than none.
Sunday December 10, 2017:
Today we had a two-fer, starting with a shop visit to Ceres Motorsports in Oviedo, Florida. This was combined with a holiday party for Central Florida British Car Club. Plenty of fine British rolling stock visiting here. A few of the cars closer to the building live here or are customer cars.
After meet and greet there was a party going on with at least 25 club members. The picture doesn't do it justice, as half the people left before I thought to get the party picture.
Ceres is doing a booming business as a full service and restoration shop, and it looks like they will be here for some time to come.
Late night WiFi stint catching up email and tech questions accumulated during the day.
Monday December 11, 2017:
Bunch of tech questions today, starting with a tech page update on speedometer cables. Got to be rather late, and still hadn't done the photos and notes from the Sunday shop visit and club party.
Tuesday December 12, 2017:
Get the priorities right. If nothing else, I had to put together a parts order and fire it off so the stuff could be delivered by Friday (we hope). Over $700 this time, so nice discount and free shipping. Another set of brake shoes, plug wires, some minor maintenance parts, a few bits to refill the magic trailer inventory, and looking forward to next gearbox rebuild. Looks like the current rendition is going to make 100,000 miles, and I want to know if a 62-Rc layshaft may be any better than 60-Rc. I doubt it, so I will be entertaining ideas on how to make a layshaft last more than 100K (because I still don't like rebuilding the gearbox every 30 months). Also day dreaming about a V6 engine and modern 5-speed gearbox (likely never to happen).
The big ticket item is a high torque gear reduction starter motor. After decades of saying I've never burned out a starter motor, I think I've finally worn one out (after 546,000 miles of service). A few weeks ago the starter began making nasty grindy-screamy noises during overrun after starting the engine, soon followed by slow cranking nearly all the time. I recon the bushings have worn enough to let the armature touch the field coils. Give it credit for 60 years faithful service. I am going to take this opportunity to install a modern gear reduction starter, not that I really need it, more out of curiosity, and this is what the guru does to test everything.
Tech page update on serial numbers for Vanden Plas aluminum hardtops. Some discussion about 86,000 mile Halo spark plugs vs. 100,000 mile Autolite spark plugs (yes I do that). Fielding another bitch note about wood door top trim rails that don't fit right. Got caught up with the Sunday photos and notes too.
Wednesday December 13, 2017:
Must have been goofing off today? Some discusson about replacement cockpit trim rails, pot metal and wood parts that not only do not fit as original but also do not mate with each other (ongoing problem). Wasted more time chatting about spark plugs, core wire size and materials (supposed) advantages (or not).
Thursday December 14, 2017:
Started the day with a fairly high priority to get an oil change, but got busy and it didn't happen (but we didn't add miles either). I did post a web page update with some very nice pictures of the spark "flare" seen when testing ignition coil polarity. Turned down an offer of a new gearbox layshaft and needle bearings from a supplier in Australia, because I already had the parts on order. If these things will not run more than 100,000 miles, I may consider stopping rebuilding the gearbox and switching to something more robust. Some discussion about how to do a Mazda Miata 1.6-liter engine and gearbox swap into an MGA. Someone intending to do this soon may get photos and notes for documentation. More day dreaming and wishful thinking about upgrading the power train in my car. Posted a new tech page on balancing flywheel and clutch parts. Bit of a tech update on side curtain retaining clips.
Friday December 15, 2017:
Back to Tech Central in Bonita Springs again today. We stashed the MGA back in the woods out of the way for most of the day. Plenty of visitors with several needing a bit of tinkering. The TR7 had the bonnet up most of the day for what turned out to be a minor problem with an easy fix. The black MGB was pretty nice, and maybe didn't need anything.
The modern Jaguar needed a little knuckle busting to R&R most of the rear bumper just to reinsert one of the back up sensors that had dropped out of place.
You may recall the Spridget from two weeks earlier (top of page) with the fresh engine and touched up gearbox. Today they were painting and baking the tubular exhaust headers. Nice trick with the heat gun providing the baking temperature. Light coat and bake followed by second coat and bake again.
The TR7 had an air conditioning problem, electric fans running but compressor clutch not engaging. We were in the process of installing a power wire and relay when it dawned on us that grounding an existing wire would get everything working. Duh? The silver MGB had whacky carburetor issues with both carbs running very lean. Some standard adjustments had it running quite well, except it could not be brought down to slow idle. Looks like the throttle valve in the rear carburetor may be off center and dragging on the carb throat to prevent full closing. The carbs will have to come off to fix that, and time was a bit short today, so live with fast idle until we find more time for the final fix.
Once the crowd thinned out some we got to tend to our MGA. Most pressing was the oil change and lube job, significantly overdue at 5500 miles (intended to do at 4000 mile intervals). The heater valve control cable had broken the center wire. Fix for that was to shorten the cable jacket and reinstall it. Not the first time, so now getting kind of short but still okay. A replacement cable stop would be in the new parts order that was supposed to arrive today (but didn't), so final connection will wait for another day. Replaced a missing stud for connection of exhaust pipe to manifold.
At day's end we took a shot at installing new air filter elements, but no-go. These were paper filters procured from NAPA on a recommendation, but turned out to be too large diameter, not fitting inside the original screens, and not even close to fitting within the original Volks covers. So off to the dust bin, and update a web page to note that this part is not suitable for the MGA. Put the K&N filters back in service.
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