Project 1974 MGB GT - The Mustard (Mit) Mobility Scooter - 6yrs ownership & the end is potentially nigh!

[Guest Hooli]

Set the points you've got fitted before you do the timing. Do it the other way round & the timing changes when the points gap is changed.

[SiC]

I reckon the points are probably gubbed if the condenser has failed and so will need to change them anyway. Infact it'll probably be a good indicator if they are damaged that it's gone.

 

Thinking about it, as I have a brand new distributor to hand, it's probably just easier to lob that on and give it a go. The gap is already set, so a case of popping it on and timing it. If I can get it just to sustain running, that'll be a big win in my book. I can then strip down the original and replace any worn parts (like springs).

 

I'm just a bit suspicious of the new distributor as I only paid £27 posted for it. It does have a red rotor in it with the initials DD inside (assumably that's distributor doctor). Providing that's not a fake red rotor!

 

This is the one I bought and where I got it from:

https://m.ebay.co.uk/itm/Brand-New-45D-Traditional-Points-Distributor-for-MGB-1964-1981/310412573850

 

Gone up slightly in price now but still cheap.

[Noel Tidybeard]

is the B-series dizzy similar/same an a-series one? would one foe a metro/maestro work?

[mercrocker]

That AccuSpark dizzy is the same as the one I fitted to my Oxford and also my present Cowley.   The Minor is still on its original but with AccuSpark electronics inside it.   I see the argument about heat sink etc. but I must have had 50000 miles out of mine across three cars without a problem.    The only ignition failure I have had since upgrading was on the Oxford when I stupidly re-fitted a black rotor arm because it was new.   It lasted about 2500 miles.   In fact, that particular breakdown was only worsened because I didn't suspect, and therefore test, the rotor arm I blamed my new electronic installation and put the points back in!

[TagoraSX]

I would avoid the Powerspark distributors which are 100% Chinese.

 

Thinking it would be a good upgrade I bought a full kit for the SD1 (including two faulty ignition modules)  it gave no end of grief. In the end the garage had to refit the original to work on the car. They will be fitting a Pertronix kit in the new year.

[danthecapriman]

I would avoid the Powerspark distributors which are 100% Chinese.

 

Thinking it would be a good upgrade I bought a full kit for the SD1 (including two faulty ignition modules)  it gave no end of grief. In the end the garage had to refit the original to work on the car. They will be fitting a Pertronix kit in the new year.

Powerspark were who made the V8 set I tried on the Mercury. It was crap and didn't fit properly despite being listed for my distributor.

[SiC]

She runs!! Runs smoother than she has done before too.

 

While the mother-in-law and my wife were in cooking boxing day roast, my father-in-law and myself were outside fitting the spare new distributor - like a proper old (fashioned) English day. I didn't bother doing anything on the old one when it looked like this.

A whole catalogue of problems with this one:

- Points connecting wire chaffed through.

- Spade connector was badly crimped and so loose, a little tug and it came off.

- Earth wire didn't look too clever.

- Points contacts were filthy, so the crappy condenser has probably gone too.

 

The clamp ring on the distributor is cracked too.

 

So the old man was right. Timing likely would have been all over the place.

[Six-cylinder]

Good news indeed.

[danthecapriman]

Good job! Fingers crossed for the drive out!

[busmansholiday]

A major success, I hope the new year is as successful as this for you, your family and the MG

[mrbenn]

Nice work! Glad to see your efforts being rewarded.

[Guest Hooli]

Hurrah!

 

Nos 8 & 18...

[SiC]

Stripped down the old distributor to see what was going on inside it. Nothing too tragic, just old.

 

Even though it's crappy looking, the bodgy earth wire seemed to be doing the job. Not idea by any stretch but not the cause of the FTP.

 

Further down was grubby but nothing too bad that I could tell. The weights do have a bit of play on the shafts. I guess this isn't too much of a problem and if it was the other way (i.e. jammed) then it would. Springs were still springy too.

 

Bottom layer.

 

Unfortunately the mounting ring was cracked (as per earlier pic). A gentle prod with a screwdriver caused it to fall off. Looks to have been damaged for a good long time. No idea if this can be fixed or if it's going to cause problems if I try to reuse the dizzy?

 

Rotor cam lobes have a lot of wear on them. Probably not a lot I can do with this apart from replace the part. I guess it's not much of a problem as setting the point gap will get around the wear?

 

Points looked knackered to me with holes in the contact coating.

 

All the bits to a 25d Distributor.

[SiC]

Onto what I think is the root cause of the FTP. Crappy cheapy condensers.

 

This is inside the one I reckon is dodgy. You can see arcing and pitting on the electrode. This electrode is simply pushed against the capacitor element, using the rubber end cap to hold it.

 

Pulling said electrode made and broke electrical contact. Hardly ideal. Moss Motors high quality condensers are potted in and the connection soldered. Much better. How they used to be manufactured before being cheaped out.

[Video]

 

For reference here is an older Lucas (probably not 70s vintage) condenser insides. This actually has an additional spring element inside to help electrical connectivity.

 

My next plan is to refit the original distributor, as the ignition curve has been designed to match the engine properly. I'll fit the Moss condenser on the coil for ease of maintenance and so I can use the spare 45d distributor with a decent condenser.

 

I've also got a external ignition amplifier to fit once the postman delivers it too. Hopefully solving any ignition woes.

[Frogchod]

Ooo, nice Fluke

[Guest Hooli]

See, told ya old cars are simple.

[Zelandeth]

Always a good idea to make the condenser easily accessed.

 

I had a Skoda Rapid which used to eat them on a regular basis for some reason that I never did get to the bottom of.

[SiC]

Compression testing using my cheap, red box compression tester got:

Cyl 4 - 140psi,

Cyl 3 - 138psi,

Cyl 2 - 135psi,

Cyl 1 - 133psi. I repeated cyl one again and got 140psi...

 

Engine was warm.HBOL says 160psi for high compression (which mine should be) and 130psi for low compression. Took about 12-14 cycles to get to that. It got to around 90psi after 3-4 cycles.

 

Now I don't know if the actual values should be taken too much into account as firstly it's a £9 compression tester from China and secondly the battery has been sitting around for a couple of weeks plus a couple of starts on the driveway - so probably a bit flat.

 

However I remember reading somewhere that what's more important is that they're consistent between cylinders?

 

Since fiddling with the carbs and running the engine, it appears stinking rich. After taking the carbs off, this is the butterfly valves.

 

 

Not overly bothered as I have a carb overhaul kit to go on these shortly.

[Mally]

It will run fine like that, the higher the better, but anything over 125 is acceptable to me providing its not smoking.

By the time you have stripped the engine and sorted everything you find, its easier/cheaper to fit a reconditioned unit.

I would advise leaving well alone, you know what will happen when you have fixed everything!

[SiC]

A quick thanks to rusty rocket for the next one.

 

Just removed the oil pressure relief valve. Went through the carb route as looked much easier than from the bottom up.

 

It's here.

 

A tip from John Twist to get the plunger bit out is to turn the engine over. Plopped out very happily when I did that.

 

Old plunger shows wear on it. Bottom is new spring.

 

The old is about 4 to 5mm shorter than the new. Drill bit in the picture is a 4.5mm one.

 

 

Hopefully this may help reduce the tapping up top?

[danthecapriman]

Brilliant job. Why is the spring so much shorter though? Just old age I suppose?

 

With the compression testing, I would do as Mally says. Leave it alone. They look ok and they're all pretty close to each other so any wear is pretty even by the looks of it. The problems come when you get very low readings or very inconsistent readings.

When my Mercury engine was rebuilt we tested the original compressions and got as much as 90% variation on some cylinders! One cylinder was essentially doing nothing it had such low compression! Of course being a huge V8 it wasn't all that noticeable when driving it! On mine it was worn bores, fucked rings and burnt out valves. The engine was basically dead and well overdue a full rebuild.

My Capris Pinto is much the same as yours sounds. Compressions aren't factory levels anymore but they're all still good, and all still very close to each other so I'm going to leave it as it is since it seems happy enough.

[SiC]

BOLLOCKS. I forgot I left that in the intake. Turning it over must have sucked it in. Managed to pull it out from in there but no idea if it's got into the cylinders.

 

 

 

Got the spring in with the cap back done up. Was quite a battle but it's now in.

[SiC]

Taken the plugs out and had a look. I can't see anything in there so I guess I've been lucky.

 

I assume kitchen roll isn't too disastrous if it got sucked in and through?

[danthecapriman]

Taken the plugs out and had a look. I can't see anything in there so I guess I've been lucky.

I assume kitchen roll isn't too disastrous if it got sucked in and through?

If it's just kitchen roll I don't think it'll stay inside for long once it fires up! It'll just get burnt and blown out the exhaust!

[Rusty_Rocket]

Nice work. The new, less compressed spring will certainly give you higher oil pressure. It is a bit of a struggle to the cap back on -that's normal. Don't worry about the little bit of paper in the inlet, the engine will quickly deal with it like Dan said!

[Guest Hooli]

What octane rating paper are you running it on now?

[SiC]

Cold start (choke) mechanism. Eww.

 

Hopefully this won't cause any issues? This bit I don't think needs to seal.

[Rusty_Rocket]

That will be ok with a clean up. It seals further down with an O-ring. Those carbs look ready for a good strip & build

[SiC]

With the HIF4 carbs, how do you/what is the base setting for the main jets? I'm also renewing the jets but not the main needle - I guess this is ok?

 

I'm really hoping after all this it won't let me down again. My mojo is starting to fade a bit with this car now.

[busmansholiday]

I have to congratulate you on your determination and dilligance on getting your MGB sorted. I haven't honestly spent this much time in total on all three of mine (apart from welding). I have the old fashioned principle that "if it's not broken, don't fix it".