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1
Cars for sale / 1966 MGB
« Last post by amgba on December 05, 2018, 12:13:32 PM »
1966 MGB. Good engine, factory overdrive, Weber sidedraft, good floods/sills, minor hit, front center. Comes with over $1000 replacement parts. Hardtop not included. $3500. 951-237-0001. CA.
2
Cars for sale / 1980 MGB
« Last post by amgba on November 28, 2018, 11:34:28 PM »
1980 MGB. $20,000 invested. New top, new 5-speed transmission, new exhaust, card and intake manifold, radiator, clutch, plus a host of other item. Most parts go with the vehicle. Rust free. $12,000. John at 907-590-0052, scandace18@gmail.com . AK
3
Upcoming Show Announcements / June 6-9, 2019 - Rendezvous 2019, Eau Claire, WI
« Last post by amgba on November 18, 2018, 12:24:12 PM »
Rendezvous 2019, Eau Claire, WI. www.mn-mggroup.org/rendezvous-2019 , Diane at 715-379-6001 or drindt4271@yahoo.com .
4
Other items for sale / Bosch Halogen Driving/Fog Light
« Last post by amgba on November 07, 2018, 12:07:52 AM »
Bosch Halogen Driving/Fog light with Mtg. bracket. 6" o.d.x 2-3/4"thick. P/N 1305601006. Have additional photo’s, $65.00 plus frt. contact Info - Tom, email: tj2407@gmail.com and cell: 443-477-4393.
5
Engine Related Items / Re: Refusing to Start Without a Bit of a Rest
« Last post by Art on October 29, 2018, 01:40:59 PM »
A:   It's kind of a rule of thumb that what looks like a fuel problem is actually an electrical problem (or vice-versa).  It feels like it electrically fails, so your attention goes to the coil and other potential issues, but it just as likely could be a fuel issue.
I had the exact same experience for a long time and it turned out to be the fuel pump.  It was an old one and it seemed to 'vapor lock' under certain conditions.  Letting it sit allowed it to bleed-off and it then functioned normally for a time after that.  Replacing the pump with the new electronic version of the SU pump has remedied the issue, without recurrence for many for years.

However, I did replace the coil, installed a Pertronix ignition system and the spark plug and coil wires before realizing the actual culprit.

That said  if the coil looks pretty with its aluminium case, it can also be bad, so I'd consider changing it for just that reason.
This would be my check sequence:

First, if you haven't, check if you have spark as soon as it dies and won't restart.  Pull a wire and and take out a spark plug. 
Holding the wire or ceramic top of the plug (do not hold the metal case of the plug unless you want a nasty shock) and ground the metal case of the plug,  Have someone turn it over and see if it sparks.  If you do, then the coil is not the culprit and I'd move on to the less obvious. If you don't, I'd then check every connection to the coil and all the ignition wire. Include checking the tach lead.  They come off or loose, the ignition is defeated and you get no spark.

Next, check if you have fuel right after it fails and won't restart.  Pull the hose off either the carb or fuel filter and hold a cup or can under it.  Have someone turn the key and see if it clicks and pumps gas.  It doesn't, you know where to look next. No clicking from the pump, that's probably the issue.  Check electrical connections first, but, if over 10 years old, pulling the pump would be good idea. If the pump is clicking, but there's no fuel at the carbs, it could be a blocked gas line or damaged pick-up in the fuel tank. Fuel flows and you have spark, go on to carbs and their floats.

Another question is - was the tank always low when the car failed?  If yes, could be rust in the tank, a damaged fuel pick-up or a partially blocked filter on the pick-up (if so equipped).

I hope that helps you.  Keep me posted on how you make out and what you find.

Safety Fast!
Art Isaacs
6
Engine Related Items / Refusing to Start Without a Bit of a Rest
« Last post by december2018 on October 29, 2018, 01:36:22 PM »
My B has developed a nasty habit of suddenly dying, refusing to start until it has had a bit of a rest, then starting and running fine, though perhaps briefly.

This happened first a few days ago when temperatures were in the low to mid 90’s.  After running fine on a return trip (20 minutes or so each way, suburban driving),  I gave it a little gas after coming to the bottom of a half mile hill.  Nothing.  Cranked fine; wouldn’t fire.  We spent five minutes or so in the heat pushing it off the busy, four lane, road and onto the side road that led to home.  I tried the starter- it fired immediately ran and got me the rest of the way home.
Later on, slightly cooler weather- two more round trips of the same sort as above; no problem. The second of those trips was yesterday; washed and waxed the car prior to a car show today.

I got up this morning temp around 50 degrees.   Drove it about five or ten minutes, turned off the busy road trying to find the show.  Wrong place.  Turned around, started back to the busy road; car died.  We did all the intelligent things we could think of with no tools; nothing made a difference.  We were about to give up, when I hit the starter again- it ran!!  Hurrah, let’s go.  Two or three minutes later, back on the busy road, and it died again.  Pushed it back to a safe place off the road.  Similar pattern- looked like plenty of fuel in the fuel filter; starter spun the engine fine, but wouldn’t even pop,  until perhaps ten minutes later when it fired (normally), and ran.  Being a bit skeptical, we let it sit for a few minutes; again, it died.  By this time a “car guy” from the show had appeared.  He was suspicious of an overheating coil, but it was not hot to his touch.  His other thought was that there may be an electronic module which was overheating.

I went to the show without the car; came back a couple of hours later, and was able to get it back home.

Your thoughts?  Any further diagnostics I should do? 

John W Philbrick
Brentwood, Tennessee
7
Engine Related Items / Changing the Distributor
« Last post by Art on October 29, 2018, 01:43:08 PM »
Changing the distributor on a B is fairly easy, especially if you have good mechanical ability.

Unlike American cars, the Lucas (or replacement aftermarket) distributors can only go in one way.  They don't have gears on the bottom, but keys and slots that are different from side-to-sided, so the rotor will always point in the correct direction.  The trick is to reasonably align the number 1 spark plug wire as it was originally.

Also, some aftermarket distributors require reusing the drive (keyed coupling) from the old distributor.  Not a daunting task, but the roll pin that retains it has to be punched-out and the coupling properly aligned on installation to the new unit.  It should be keyed to the shaft, so that becomes easy.

Little tricks:
- Mark all the park plug wires on the cap.  If you don't have the the electrician's numbered bands, a piece of masking tape with the number written in dark ink (Sharpie or gel pen) number works fine.  Make sure the number one plug wire is especially clear.
- Mark the block where the number 1 plug wire is positioned on the distributor. Just helps to get the new distro positioned so the car will start to be able to set the timing with the light.
- Take at least 2 photos of the old distributor before removing it.  One with the cap on (so you can see the #1 plug wire and Vacuum advance pot positions) and the other withe cap off (to see the rotor direction).
- Remove the cap, primary leads (with the CEI you have to also remove the module), the 2-bolt clamp that retains the distributor and just pull it out.
- Remove the clamp from the old distributor (single bolt length-wise across the split side of the clamp) and check the clamp is not bent and the bolt is free and can be adjusted. Repair or replace as necessary.
- Reinstall the retaining clamp to the block with the adjustment bolt still somewhat loose.
- Install the new distributor with the rotor in place.  The rotor should automatically line-up as the keys in the bottom of the distributor should only fit the same way as the old one did.  Determine where the #1 wire would be (that can vary between distributors relative to the vacuum advance pot) and set the body of the distributor so that it is in the same place, either using the photos you took or the mark on the block.

Now, depending on which way you went on the replacement distributor determines what you do next.   I'll follow the 45D4 installation with a Pertronix kit as that's what I'm most familiar with.  The others, being completely different, should come with full instructions, but will only differ in the controls and associated wiring.

With the distributor in place, rotor and cap off, install the Pertronix unit.  A sensor cap goes over the cam that actuated the points on the shaft just below the rotor. 2 screws that used to hold the points in place now secure the reader unit to the plate. 
The kit comes with the wires that replace the primary lead and power source and they have to be snaked through the hole in the lower distributor body the primary lead had gone through.  Instructions are provided.  Make sure in ordering the distributor and Pertronix kit that they match by model.  The kit for a 25D4 will fit the points plate, but the wiring harness is very different and won't fit.  And caps and rotor are not interchangeable.

Fit the cap, wires and vacuum advance line and start the engine.  Once warmed-up, remove and plug the advance line, adjust the idle, fix your timing light and set the timing.  Once set, adjust the idle, tighten the clamp, reconnect the vacuum line* and done.

My personal advice here is a reminder that, with a turbo, the vacuum advance my be hooked up differently or bypassed entirely.  The intake manifold is now under pressure from the turbo, so it won't work conventionally.  With a draw-through set-up (carb before the turbo) it can use fittings on the carb to work pretty much normally, but if you have a blow-through set-up (carb after the turbo), the carb is now under pressure, so no vacuum. 

This could influence your distributor kit purchase, as it may be best to get a fully mechanical advance type distributor, like the one from Crane.  Check and make sure what you have before buying anything.
Moss sells their supercharger kit, so see what distributor they use on that.  Also, sources, like JEGS or Summit Racing carry aftermarket distributors and Pertronix kits for the MGB that may be better suited to your application. 

They routinely work with supercharged and turbocharged racers and hot rods.

Safety Fast!
Art Isaacs
8
Electrical Items / LED Headlight Conversion
« Last post by amgba on October 29, 2018, 01:48:09 PM »
I just installed my new LED headlight conversion to go along with my relay conversion I did a while ago what do you think?
No need for extra driving lamps with these!

Dale Schiller
9
General Discussion / LED Headlight Conversion
« Last post by amgba on October 29, 2018, 01:48:09 PM »
I just installed my new LED headlight conversion to go along with my relay conversion I did a while ago what do you think?
No need for extra driving lamps with these!

Dale Schiller
10
General Discussion / Changing the Distributor
« Last post by Art on October 29, 2018, 01:43:08 PM »
Changing the distributor on a B is fairly easy, especially if you have good mechanical ability.

Unlike American cars, the Lucas (or replacement aftermarket) distributors can only go in one way.  They don't have gears on the bottom, but keys and slots that are different from side-to-sided, so the rotor will always point in the correct direction.  The trick is to reasonably align the number 1 spark plug wire as it was originally.

Also, some aftermarket distributors require reusing the drive (keyed coupling) from the old distributor.  Not a daunting task, but the roll pin that retains it has to be punched-out and the coupling properly aligned on installation to the new unit.  It should be keyed to the shaft, so that becomes easy.

Little tricks:
- Mark all the park plug wires on the cap.  If you don't have the the electrician's numbered bands, a piece of masking tape with the number written in dark ink (Sharpie or gel pen) number works fine.  Make sure the number one plug wire is especially clear.
- Mark the block where the number 1 plug wire is positioned on the distributor. Just helps to get the new distro positioned so the car will start to be able to set the timing with the light.
- Take at least 2 photos of the old distributor before removing it.  One with the cap on (so you can see the #1 plug wire and Vacuum advance pot positions) and the other withe cap off (to see the rotor direction).
- Remove the cap, primary leads (with the CEI you have to also remove the module), the 2-bolt clamp that retains the distributor and just pull it out.
- Remove the clamp from the old distributor (single bolt length-wise across the split side of the clamp) and check the clamp is not bent and the bolt is free and can be adjusted. Repair or replace as necessary.
- Reinstall the retaining clamp to the block with the adjustment bolt still somewhat loose.
- Install the new distributor with the rotor in place.  The rotor should automatically line-up as the keys in the bottom of the distributor should only fit the same way as the old one did.  Determine where the #1 wire would be (that can vary between distributors relative to the vacuum advance pot) and set the body of the distributor so that it is in the same place, either using the photos you took or the mark on the block.

Now, depending on which way you went on the replacement distributor determines what you do next.   I'll follow the 45D4 installation with a Pertronix kit as that's what I'm most familiar with.  The others, being completely different, should come with full instructions, but will only differ in the controls and associated wiring.

With the distributor in place, rotor and cap off, install the Pertronix unit.  A sensor cap goes over the cam that actuated the points on the shaft just below the rotor. 2 screws that used to hold the points in place now secure the reader unit to the plate. 
The kit comes with the wires that replace the primary lead and power source and they have to be snaked through the hole in the lower distributor body the primary lead had gone through.  Instructions are provided.  Make sure in ordering the distributor and Pertronix kit that they match by model.  The kit for a 25D4 will fit the points plate, but the wiring harness is very different and won't fit.  And caps and rotor are not interchangeable.

Fit the cap, wires and vacuum advance line and start the engine.  Once warmed-up, remove and plug the advance line, adjust the idle, fix your timing light and set the timing.  Once set, adjust the idle, tighten the clamp, reconnect the vacuum line* and done.

My personal advice here is a reminder that, with a turbo, the vacuum advance my be hooked up differently or bypassed entirely.  The intake manifold is now under pressure from the turbo, so it won't work conventionally.  With a draw-through set-up (carb before the turbo) it can use fittings on the carb to work pretty much normally, but if you have a blow-through set-up (carb after the turbo), the carb is now under pressure, so no vacuum. 

This could influence your distributor kit purchase, as it may be best to get a fully mechanical advance type distributor, like the one from Crane.  Check and make sure what you have before buying anything.
Moss sells their supercharger kit, so see what distributor they use on that.  Also, sources, like JEGS or Summit Racing carry aftermarket distributors and Pertronix kits for the MGB that may be better suited to your application. 

They routinely work with supercharged and turbocharged racers and hot rods.

Safety Fast!
Art Isaacs
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