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J.Fuller
30th November 2009, 21:16
Hi All,

The Rat recently made an Epic trip up to Lancaster on the M6, my first motorway driving, and very good fun. The fun continued upon arrival in 'town, where the 1.3 A+ series engine decided to fail me, for the first time ever!

So, here's some throughts from before and after the events, and an experssion of my confusion, I hope someone can suggest what might have gone wrong.


Pre Flight Checks:

Before departing to Lancaster, I filled up with fuel (BP unleaded, 95 Octane), and also added just under half a botle of Reddex to the tank for a clean out en-route. I topped up the carburettor damper with oil, which had fallen below the specified level. I made attempts to check the condition of vacuum pipes (as had allready replaced one perished hoze). I was particularly keen to test the pipe to the distributor, as I have been having some issues with the engine kicking back when I switch off). I was unable to do this without risking breaking a pipe, and so made the decision to go.

The car performed flawlessly all the way to Lancaster. It idled at lights and sustained 70 on the M6, all in order.

What happened?

The engine cut out in rush hour traffic, at speeds mostly below 20mph. (My first chance to use the hazard lights and push the car to safety on afew occasions). The engine refused to start upon stalling, for several minutes in each instance (happened 5 times total!). But: the engine would start after a pause of maybe 4-5 minutes, and would then run for a variable amount of time before cutting out again (usually a few minutes later).

When the engine lost power, the momentum of the car/engine would often keep it moving, but once it had began to struggle, it would always die. I started to practice left foot braking when out of gear in traffic, in an attempt to keep the revs up!

What I did:

Eventally, I consulted the Haynes manual and then did the following.

1) Inserted a length or rubber tube into the tank breather pipe (in the filler neck) and blew the pipe through in case of obstruction. - Possible cause No.2 fuel starvation caused by vacuum in the fuel system.

2) Got the bonnet up, and noticed that the vacuum hoze to the distributor had either fractured or melted through (not sure here, perhaps i weakened it, or disturbed it while trying to do my test). So i repaired the broken hoze. - Possible cause No.2, fueling issue relating to leaking vac system (unlikely as it ran before with a perished hoze, for a few hundered miles).

3) Examined the ignition coil low voltage connections, and found one of the spades to be a little loosed than i would have liked, so tightened up the connector with my pliers. ;) Possible cause No.3 - Ignition fault.

After these 'remedies' the car ran flawlessly, and has done ever since. I tested the delivery of the fuel pump and looked at the guts of the filler cap the next day, and saw nothing out of order. I have not been able to identify a fuel filter before the gauze on the jet (shown in Haynes), and have not looked into this yet.

The only other things to note are that the car still kicks back occasionally when I switch off. The engine actually tries to run backwards, as stalling in first makes the car move back a little!

Anyways, if you managed to read this far, well done! Has anyone got any suggestions as to what might have been the problem , and what i could investigate next?

With Many Thanks,

Joe

E_T_V
30th November 2009, 21:29
Probably an electrical fault from your description above, so tightening up the connector probably solved it.

As for the engine running on, then that usually indicates the need for a tune up. There is no point in doing this until all the vacuum pipes are in good condition (the cause of almost all A series running faults).

There is a bit of a tuning guide in the FAQ section somewhere which I wrote a while ago.

J.Fuller
1st December 2009, 12:23
Thanks E_T_V, think its going to be a Christmas tune up after a full inspection of the vac system. Noticed the tuning guide previosuly, so I will let you know how I get on.

Cheers,

Joe

RobertP
1st December 2009, 18:29
I had a very similar problem on my 1.3 Maestro (stopping for no apparent reason, especially on a rough surface [clue there???]). It was a loose spade connector on the coil. I was surprised it had worked at all, it was so loose. These engines are very forgiving! ;)

maestro vans
2nd December 2009, 00:42
Overun is usually down to vacuum pipes come off or perished
check thay are in good condition

E_T_V
2nd December 2009, 10:32
That or the idle speed is set too high.. The A series idles pretty slowly compared to modern engines.

D B Geere
2nd December 2009, 11:17
You could also check the crankshaft sensor. I had this problem with my 'O'series engine in the Montego when it would cut out whilst driving. Wait five minutes and it would restart. Good luck. D B G

E_T_V
2nd December 2009, 12:29
The A series doesn't have this sensor, but the O series and S series do. Not sure on the R series though.

Crank sensors usually pack up when the engine gets warm. And then often mysteriously work again once the engine is cold.

The giveaway aside from this is that the rev counter will bounce up and down when the failure happens.

henocsr
5th December 2009, 20:07
You could also check the crankshaft sensor. I had this problem with my 'O'series engine in the Montego when it would cut out whilst driving. Wait five minutes and it would restart. Good luck. D B G

As ETv said a seriesdont have acrank sensor, they have a pick up in the distruibutor which is wired to the ignition module.

You are quite right and this pick up could give a simular problem

J.Fuller
12th December 2009, 19:38
Thanks for the further input. Maestro cut out again today. Notably after a period of sustained idle, following another top run down the motorway. I checked the fuel cap, but no signs of a vacuum issue, then bonnett up and looked at the coil connections. Gave the spades a waggle and got back in, waited and then fired up fine. Intersting how the spade connector i had perviously tightened seemed loose again, but perhaps my standards are improving!

Got home (5 mins) and waggled the spade connector in the hope of seeing the engine miss, but it ran faultlessly until I removed the spade entirely.

Humph, re-wire coil and investigate fuel system.

Cheers,

Joe

KRM
13th December 2009, 12:40
What I believe can happen is the following. As the car warms up under the bonnet the ilcoil get warm to this causes the clips to expand, the clip expand at a greater rate than the terminals on the coil. When the car stops the clips lose heat quicker than the terminals on the coil, therefore a better contact is made-for a few minutes!

I found this out many years ago when I was fixing a friends Austin 7 Chummy with a magneto perfect when cold night mare when hot. The brushes were stuck they made contact with the commutator when hot the body expanded and the brushes lost contact with the commutator, took 3 days and night! to find the problem.

Hope this helps


KRM

J.Fuller
8th January 2010, 14:16
Update on the engine.

Removed the air box to access the tappets, and found that the rubber gasket between the airbox and the carb had been disturbed....

The gasket had come off the locating spigot on the plastic air box and this had been mashed into the assembly about 1/2" off centre. Hence there was a vacuum leak on one side of the gasket, and part of the gasket was covering a small portion of the inlet port. What a mess!

Does anyone know the correct spanner size for tappet adjustment; my cheap metric ring spanners might be out, but i believe an impreial size is used? If anyone would be so kind as to advise, I will go and buy a quality spanner with the correct opening.

Many Thanks,

Joe

G Force
8th January 2010, 15:23
Does anyone know the correct spanner size for tappet adjustment; my cheap metric ring spanners might be out, but i believe an impreial size is used? If anyone would be so kind as to advise, I will go and buy a quality spanner with the correct opening.

Many Thanks,

Joe

1/2in AF is the size, if you can get hold of a combination spanner with a hex type ring end and a long handle this is the ideal. Saves grazing knuckles.:D

G Force
9th January 2010, 11:57
With regard to your cutting out problem, from reading your description of events, it sounds to me like the carburetter could be flooding.

To cure this you would need to fit a new needle valve and seat kit (GSU104) then reset the float hight. The carb needs to be removed to do this.

To set float height you first need to remove the bi-metal strip assembly and main jet. Invert the carb and lay a thin straight edge (I use a 6in steel rule) over the carb body and the centre of the curved indent of the float. Measure the gap between the centre of the float curved indent and the straight edge with narrow or wire feeler gauges; set the gap to 1mm 0.040in by bending the brass tang on the float. The measurement is taken without the ball on the needle valve being compressed.

Cheers, G Force:)

J.Fuller
9th January 2010, 23:03
Thanks G Force,

I will get the tappets set, then progress to carb adjustments when it gets a little warmer!

Cheers,

Joe:)