740 poor running and stalling

[Beadybc]

Originally Posted by Laird Scooby

None of the above!

If you look at your pics, you'll see in one of them there is the metal end still in the bracket and you can see where the rubber has come away and it's basically a flat disc. Imagine a couple of normal bolts but with the heads replaced with similar flat discs. Have a jig so these bolts could be held securely with a gap in between and this gap is fill with rubber, polyurethane or nitrile compound and allowed to set.

It bonds to the flat discs so the two threaded parts are now held apart (and together!) by the rubber/PU/nitrile in the middle.
Because the compound in between the two threaded parts is fairly strong it will support various weights but more importantly, dampen vibration from one end to the other of the mounts while returning to it's original shape when the vibration stops. This makes them resilient, hence the name of resilient mounts.

They are used a lot in NVH engineering (Noise, Vibration and Harmonics) to prevent noise being transmitted, vibrations which may eventually cause mechanical damage or other problems. Perfect exhaust mount for a classic Mini or the noise and vibration from the exhaust would transfer to the floorpan creating a sounding chamber better known as the passenger compartment.

As you can probably guess, you wouldn't really want vibration from the engine upsetting the mixture in the fuel distributor (easily done as it's controlled by an air-flap on a spring, lifted by incoming air to the engine) which is why the fuel distributor is mounted on them.

Ah thanks Scooby I was under the impression that the side that has been flattened and is still in the fuel distributor unit was part of the unit. I was quite confused when you said that new units don't come with them.

[Laird Scooby]

Originally Posted by Beadybc

Ah thanks Scooby I was under the impression that the side that has been flattened and is still in the fuel distributor unit was part of the unit. I was quite confused when you said that new units don't come with them.

You're welcome, you should be able to unscrew that bit fairly easily but check for hidden locknuts on the end of it!

[Beadybc]

Originally Posted by Laird Scooby

You're welcome, you should be able to unscrew that bit fairly easily but check for hidden locknuts on the end of it!

Took out the entire unit in order to get the old mounts off. Going to replace the gasket as I have one and thought that if things getting stuck and clogged inside could be a cause of the poor running then I should try cleaning it out whilst its off the car, could I clean it out and if so, with what?

(Photos attached of it disconnected)

[Laird Scooby]

Originally Posted by Beadybc

Took out the entire unit in order to get the old mounts off. Going to replace the gasket as I have one and thought that if things getting stuck and clogged inside could be a cause of the poor running then I should try cleaning it out whilst its off the car, could I clean it out and if so, with what?

(Photos attached of it disconnected)

Gasket?

DO NOT strip it down!

There are parts inside that need special setting up procedures, you can try some carb cleaner through it once you've got it all back together and running on the car via the air intake on it but i wouldn't touch anything else other than making sure the electrical connections to the warm up regulator are good and clean and the hole in the bottom of the WU reg is clear and not filled with rust.

Other than that, keep it upright, don't shake it, don't play with the air flap, just refit with new mounts and make sure the sock is intact etc as previously advised.

[Beadybc]

Originally Posted by Laird Scooby

Gasket?

DO NOT strip it down!

There are parts inside that need special setting up procedures, you can try some carb cleaner through it once you've got it all back together and running on the car via the air intake on it but i wouldn't touch anything else other than making sure the electrical connections to the warm up regulator are good and clean and the hole in the bottom of the WU reg is clear and not filled with rust.

Other than that, keep it upright, don't shake it, don't play with the air flap, just refit with new mounts and make sure the sock is intact etc as previously advised.

If that's the case then I'll leave it as it is. I've attached photos of the gasket that I was referring to, as well as the replacement one.

[Laird Scooby]

Originally Posted by Beadybc

If that's the case then I'll leave it as it is. I've attached photos of the gasket that I was referring to, as well as the replacement one.

Don't touch it! Like i said further up, there are a lot of things needing specialised kit and knowledge to set them up right, even disturbing that gasket could alter your fuel pressure to the injectors to the point it doesn't and never will run again.

[Beadybc]

When we had a mechanic around before he recommended getting a new cold start injector. I've just looked into the connection to it and noticed that there's rust sitting inside. Is this a problem?

[Laird Scooby]

Originally Posted by Beadybc

When we had a mechanic around before he recommended getting a new cold start injector. I've just looked into the connection to it and noticed that there's rust sitting inside. Is this a problem?

That's the banjo bolt, shouldn't have rust there. Clean it out with carb cleaner and refit - make sure it doesn't leak once pressurised though, you may need new crush washers for it.

You've had the engine running albeit not well which proves the cold start injector is working or that the mixture is close enough to get it to run anyway.
The cold start injector only functions during cranking when the temperature is below a certain point (10C rings a bell but i'd have to double-check that) and then only for 8 seconds maximum so i seriously doubt that's the problem.

[Beadybc]

Originally Posted by Laird Scooby

First of all, did it run at all before you replaced the fuel? Second, how much have you put it? Third, how long was the car stood?

Fourth, go to your local Toolstation and buy :

https://www.toolstation.com/methylated-spirit/p99550

Add the contents to the fuel tank, start the car and let it run for 5-10 minutes then see what it does.

What gap did you set the plugs to when you did them? Should be 0.65-0.7mm (0.025-0.028")

Sixth, the timing is non-adjustable on that engine.

Seventh, you only have an AAV (Auxiliary Air Valve) you don't have an AICV (Air Idle Control Valve) so the idle speed won't be maintained at 900rpm regardless. The AAV is working, you've proved that.

Eighth, inspect that rubber sock between the throttle body and the fuel distributor for splits, perishing and security - any leaks there will cause your symptoms.

Ninth, buy some Carlube ATF-U, NAPA MV or Dexron III synthetic ATF. Buy a gallon of petrol in a fuel can and add ~1/4-1/3pt (150-200ml) of the ATF to the fuel, replace the lid and give it a shake to mix it then add it to the fuel tank - don't add any more fuel at this stage. Also add about a pint (0.5L) of the ATF to the engine oil.

Start the engine and let it run for 15-20 minutes at idle - don't be tempted to blip the throttle to "test it" - once it's run like this for 15-20 minutes, gradually push down on the accelerator and see how it goes.

Tenth - remove the trim panel under the dash below the steering wheel. Look up and you should see a single ECU for the ignition - there should be a neutral coloured nylon tube ~4mm or 3/16" OD going to it with a short rubber link tube about 25-30mm long (about an inch) to connect it. Make sure this is connected.

Lastly, let us know how you get on. It sounds suspiciously like lack of use combined with condensation in the fuel, dried rubber seals and/or sticking components in the fuel distributor and possibly splits in the air sock between the fuel distributor and throttle body.

Also worth cleaning the PCV system out but that won't normally cause the problems you've got, at least not on a K-Jetronic engine which is what you have there. Just to clarify things, it doesn't have a Lambda-Sond badge on the radiator grille, a catalytic converter and Lambda sensor does it? If so that makes it a KE-Jetronic which increases the fun-factor ten-fold! (For "fun" read complications!)

Oh yeah, check the air filter is clean as well.

Running the engine with the ATF has cause the fuel pump to start whining loudly.

I've now tried everything on the list to no avail. Took out the spark plugs and noticed that as well as the spark plugs being sooted which I already knew, spark plug 3 was covered in fuel when I removed it.

Using new plugs (with the correct gap) made no difference.

Attached a photo of all of the spark plugs, closest to the driver on the left and furthest on the right.

[Laird Scooby]

Sounds like #3 plug lead is either defective or not making proper contact or #3 plug is defective.

The fuel pump whine will disappear, it's probably been a while since the pump could actually move at a sensible speed.