149 replies to this topic

[GraemeC]

Looking better at the link, hose off the roll might not work as the carb end is a smaller bore (its a long time since I used a standard breather set up).

So it may be better to buy the proper hose next time you order something, in the mean time you could temporarily fix the hole with some good strong gaffer tape - its a breather so not under an significant pressure.

[Ethel]

Hose will squeeze down well enough. Stopping a larger/stiffer hose flexing in to the fan will be harder, but the genuine article isn't that pricey if you're ordering other bits.

 

Aluminium tape is great stuff as it has a bit of rigidity that stops it peeling & unravelling. You'd have to cut a reasonably thin strip to wrap it on a curve without creasing though.

[Marc13]

ok, hose sounds easy enough, I'tt tape it for now and order a replacement (so i know its sorted)

I'll have to pop back out and have a look at the bolt....I assume you are talking about the big long one running from under the green house towards the yellow circle I draw.

I'll check it - but if memory serves its like a restraining bolt (nothing more)

 

Just so I'm certain on the wiring - the one i have to remove and tape up - (looking at the last photo showing the coil on page 7) - its the one on the lower +ve. The upper positive being the new connection lead to the distributor module...is that right?

[Ethel]

Wiring sounds right, it was more obvious in earlier photos - yellow/white joining a pink/white at an unconnected spade terminsl. You just need a +ve & -ve from the dizzy module (don't mix 'em up!) and a +ve supply to the coil. Rev counter will add a  connection giving 2 x positive & 2 x negative.

 

The bolt is the one with a big head going in to the  branch of the inlet manifold feeding 3 & 4 cylinders, there's a little hose connector on the other branch (for a vacuum gauge) that could also cause a minor air leak. It's a MG Metro manifold

 

 

https://encrypted-tb...zHMSsQ&usqp=CAU

[GraemeC]

Ethel - "Let's remember this was a running car with an intermittent fault." It's not that likely to be an air leak from undisturbed manifold connections. 

Sorry - couldn't resist! 

 

In all seriousness - it is worth checking the points out Ethel mentions, especially as it is a simple visual check and doesn't cost anything. At this stage I wouldn't be ruling anything out!

 

However get the wiring sorted.  Everything you're describing makes me think it is running far too rich, which it would be with the choke out.  But the fact it won't fire without choke makes me think the spark is weak. The bang you heard is probably a back fire as it burns off the rich mixture.

[Ethel]

The point I was trying to make was don't start tinkering with the ignition timing or mixture adjustment until you've eliminated the other possibilities. It will be rich if it's sucked through several strokes worth of fuel/air & failed to ignite 'em. The backfire is mostly likely because there was fuel in the exhaust when it finally did manage to fire.

[Marc13]

Wiring sounds right, it was more obvious in earlier photos - yellow/white joining a pink/white at an unconnected spade terminsl. You just need a +ve & -ve from the dizzy module (don't mix 'em up!) and a +ve supply to the coil. Rev counter will add a connection giving 2 x positive & 2 x negative.

The bolt is the one with a big head going in to the branch of the inlet manifold feeding 3 & 4 cylinders, there's a little hose connector on the other branch (for a vacuum gauge) that could also cause a minor air leak. It's a MG Metro manifold


https://encrypted-tb...zHMSsQ&usqp=CAU

[Marc13]

Sorry sent the above too soon. Just triple checking on the wiring so I dont bugger anything up. Dizzy module occupies 1 x +ve and 1 x -ve, which I leave alone. I remove the other wire from the +ve....which will be replaced by the new white wire from the fuse box. I leave the 2nd -ve alone which is the rev counter??
The new white wire needs to be something around 14 amps?
A bit more info for you - the bright red wire from the top left of the fuse box goes straight inside the car and connects to the rev counter (along with the other wire, that if you remember, was broken and i repaired)

[GraemeC]

Yes - your wiring summary sounds correct.

 

So the red wire is providing power to the rev. counter and the wire from the coil is providing the signal.

Admittedly, it’s an odd way to pick up the power - I would’ve found a feed already in the dash area. If there is a spare terminal on the top right of the fusebox (directly under the green wires) then you could move the red wire to there, which would make the fed to the rev counter a fused supply.

Edited by GraemeC, 08 October 2020 - 08:34 PM.

[cal844]

Yes - your wiring summary sounds correct.

So the red wire is providing power to the rev. counter and the wire from the coil is providing the signal.
Admittedly, it’s an odd way to pick up the power - I would’ve found a feed already in the dash area. If there is a spare terminal on the top right of the fusebox (directly under the green wires) then you could move the red wire to there, which would make the fed to the rev counter a fused supply.

I agree, the correct wire colour (Iirc) for rev. Counter is green/orange on a later loom...

Edited by cal844, 08 October 2020 - 09:38 PM.

[Marc13]

I think there is room for the red rev counter wire to go on to the top right of the fuse box....which would then leave room for the new white wire to go to the coil :)

 

Ethel mentioned the possibility of a white wire being tucked away somewhere, that I may be able to use. Dosen't look like there is. However (see 1st photo below where white arrow is pointing to).... this white wire just goes to an unconnected spade. The wire comes up from lower in the engine by the front grille....its impossible to trace it further back, without really taking a lot of things apart. Could this be the white wire that Ethel was referring to (and could be connected to the coil for the un-ballasted ignition)? Or is this something else entirely?

 

Also - Ethel mentioned the large bolt near the manifold. See second picture below.

Red blob - is this the bolt? And is there something specific I should check?

Small yellow arrow - whats this that is sticking up? And should there be something connected to it?

Blue blobs - one of these at each side of the manifold. Just looks like a circular hollow thing projecting....should there be something connected?

[Marc13]

Further to the above post about the red rev counter wire/fuse box.

Just gone to move the wire to the top right, and typically there is no slack. It won't reach across - so I'll have to extend it...what amp wire should I be looking at for this, just want to make sure I'm using the correct one?

[Ethel]

The black spade you've arrowed was originally on the coil. If there is a hidden original it'll be tucked under the wrapping taped alongside the pink/white.

 

Yes the red dot, but it looks fine in that photo - assuming it isn't inches long.

 

It's a water heated manifold without the water hoses plumbed in.

 

Think your photo's got cropped but I'll guess you're looking at  a small barbed pipe sticking up out the top of the manifold? I mentioned it above, vacuum gauge connection - block it off, a bit of hose with a screw in the open end, or more tape.

[Marc13]

The black spade you've arrowed was originally on the coil. If there is a hidden original it'll be tucked under the wrapping taped alongside the pink/white.

 

Yes the red dot, but it looks fine in that photo - assuming it isn't inches long.

 

It's a water heated manifold without the water hoses plumbed in.

 

Think your photo's got cropped but I'll guess you're looking at  a small barbed pipe sticking up out the top of the manifold? I mentioned it above, vacuum gauge connection - block it off, a bit of hose with a screw in the open end, or more tape.

I assume its not a problem about the water hoses not be connected with that manifold?

Do you think the hose required to block off the vacuum gauge connection will be the same size hose (so i can just order one type) as I need to for the carb fuel overflow (that currently has nothing connected to the brass nozzle)?

[Ethel]

Not a problem really. Opinions differ, but I reckon heated manifolds are worthwile on a road car. If the steel inserts aren't too crusty to take a hose, you could look at running your heater plumbing through it in the future.

 

A vacuum advance pipe end will fit the bare nipple iirc, almost anything will do to block it from sucking air/dirt. You might find plenty of other uses for a length of adhesive heat shrink if the ignition is a taster of what you have yet to find.