wingertzahn

Member
OK so this is an intermittent problem where my 1979 Landy Series 3 just splutters and dies. It has been going on for over a year but is now becoming more frequent. Before I ask for advice: I’ve replaced the fuel tank, checked breathers and filters, replaced the fuel pump (mechanical) and removed disassembled cleaned, serviced and refitted the Weber 34 ICH carb. So I’d be surprised if it’s fuel starvation. On the ignition side have fitted new alternator, new coil and last year fitted an electronic ignition. And still it happens. I can SOMETIMES tell its going to happen because the engine tone includes a sort of fluttering sound and it starts to struggle just a little on hills. It also SOMETIMES seems to be induced after I’ve driven on rough ground either off-road or on an uneven/pot-holed road (and even then it doesn’t stall immediately). So I’ve also checked around for loose components but can’t immediately see anything. When a stall occurs I just wait for between 2 and 10 minutes and then she starts up again and off I go sometimes running normally for a few days, sometimes stalling again just a few minutes later. I’m at the end of my tether and limit of knowledge now. Any wise people out there lead me to the next steps (or perhaps identify the problem!)???
 
Last edited:
Does that model carb have a 12v fuel solenoid , bad connection getting loose on bumpy ground?
What is timing chain like worn can affect timing
 
Does that model carb have a 12v fuel solenoid , bad connection getting loose on bumpy ground?
What is timing chain like worn can affect timing
No - its a standard Weber 34 ICH which I've already taken apart and serviced with new jets and gaskets. I'm going to have another go tomorrow at adjusting the volume and fast idle screws just to make sure the inlet manifold isn't choking with a rich mixture - but I really doubt that's the source of the problem....

I don't know about the timing chain - not sure how I'd go about checking it,,,,?
 
Try giving the ignition coil a direct feed in case it is a supply issue with ignition circuit.
 
I have found with my petrol series 3, when the front of the car is facing up hill, it struggles. I believe the fuel pump just doesn't send enough petrol to the carb. It only seems to happen on steep hills so I'm not overly concerned. Replacement fuel pumps are not very good, if your new one only cost about £20 it will be one of the not very good ones. I good bet is to replace the old mechanical fuel pump with an electric one. Other than that, I would be looking for a loose wire somewhere between the ignition switch and the coil or coil to distributer. Have you got a transparent fuel filter between the pump and carb? If so, is ther plenty of fuel in it when the engine stalls?

Col
 
I would look at the ingnition switch, the dizzy cap and HT leads unless they were changed with the electonic ign, the fuel pipes - (they can delaminate and block intermitently). The other thing is to get it on a rolling road with some sensors on the exhaust and ign and try to narrow it down. Just to show how left field these can be:
A mates misfire under acceleration that had him stripping and tuning the carb for weeks turned out to be an HT lead tie-wrapped too tight and pulling out the coil when the torque came on the engine.
A missfire on my motorcyle that only happend over 70 and went of for weeks turned out to be my key fob flapping and turning the ign switch.
You have to work through everything, even the most unlikely and bizarre. Keep a record, its like a detective story, somewhere there is a pattern.
 
Quickest way is a wire direct from battery to coil, but not practical over time do you have a spare switch on the dash or interior light switch.
If you have interior light switch disconnect the light from switch and run a wire to coil.
 
Replacement fuel pumps are not very good
It could be that the pump is not delivering enough fuel, especially when the fuel is sloshing about in the tank (going uphill, offroad) or the engine is under sustained load. The first step is to find out if it's a fuel or ignition problem.
When the engine dies and you wait for a few minutes, does it fire up immediately, or do you have to crank it for a while? I'm thinking that, if it's fuel starvation, the carb will be empty and it'll need a bit of cranking to refill and fire. If it's an ignition problem then it will start up immediately.
 
It could be that the pump is not delivering enough fuel, especially when the fuel is sloshing about in the tank (going uphill, offroad) or the engine is under sustained load. The first step is to find out if it's a fuel or ignition problem.
When the engine dies and you wait for a few minutes, does it fire up immediately, or do you have to crank it for a while? I'm thinking that, if it's fuel starvation, the carb will be empty and it'll need a bit of cranking to refill and fire. If it's an ignition problem then it will start up immediately.
Thanks for the advice. I don’t think it’s fuel - the entire fuel system has either been replaced or serviced. The last time it stalled and stopped there was clearly fuel in the glass filter just before it goes into the carb. Also after waiting just a few minutes she starts straight away and most of the time then drives as normal until the next time she stalls.
 
One more ? where is the fuel hose to carb routed ie does it go above anything that heats up?
You can get vapour lock in the fuel hose if it gets too hot.
Post some pics of your engine bay may give us some clues.
 
Quickest way is a wire direct from battery to coil, but not practical over time do you have a spare switch on the dash or interior light switch.
If you have interior light switch disconnect the light from switch and run a wire to coil.
Ok so I fixed a direct line from battery to coil and took her for a spin for 45 minutes yesterday. Up and down hills, on the flat and on rough tracks she seemed to perform pretty much ok though I think she’s still struggling a bit under pressure in 4th. But no stalls. So - plan is to keep it this way inti the New Year to see if it is a cure - it’s a bit ‘how long is a piece of string tho’. - she can go for weeks without stalling then stall multiple times in a day! Time will tell. By the way - completely forgot that she would keep running when I turned off the ignition! Bit of a surprise that but quickly got used to it. Might well run it to a switch in the cab.
 
One more ? where is the fuel hose to carb routed ie does it go above anything that heats up?
You can get vapour lock in the fuel hose if it gets too hot.
Post some pics of your engine bay may give us some clues.
So here’s a pic of the engine compartment - you can clearly see the bypass I’ve fired from the battery to the coil. Also attached is a pic of the in-line fuel filter immediately after the last stall.
 

Attachments

  • 9BAEDFB9-6C70-4936-A084-E16715270C83.jpeg
    9BAEDFB9-6C70-4936-A084-E16715270C83.jpeg
    350.6 KB · Views: 1,527
  • B53E20DB-0F7C-4034-8A91-F04DD79658A7.jpeg
    B53E20DB-0F7C-4034-8A91-F04DD79658A7.jpeg
    193.9 KB · Views: 304
The angle of the fuel filter might be the cause, it would need to be virtually full for the engine to run consistently, my filter never seems to fill but it is horizontal so the fuel flows throughout it without having to worry about gravity. Can you re-route the fuel pipe so the it is horizontal or better still, have the outlet side facing downwards slightly.

Col
 
Also, it's not very clear but it looks like there is some sediment in the fuel filter, is this the case? If so, change it.

Col
 

Similar threads