45 Series 2f Engine stalling at speed

[Pollardd]

Hi Everyone,
I have a 45 series Troopie (84 model I think). It has been running very well recently.
The other day I drove it 15km into town along a country road at around 80 Kmph.
After about 10km it startes stalling at high speed. It was very sudden like power on to power off completely with no warning. After the speed reduced for about 10-15 seconds the engine would kick in again. Another few km down the road the cycle started again. Sometimes it would roll to a stop and I would wait a minuted and start her up again and off I would go. The distance between stalls gradually reduced until I was lucky to make it home.

I'm trying to figure out what the problem is.

I don't think it is a fuel problem because If I leave the accelerator in the same position while I'm coasting along when it kicks back in I was getting a back fire. This tells me fuel was still flowing while the spark was not.

I don't think this could possibly be an air intake problem so that only leaves spark.

I replaced the old breaker point distributors few years ago with an electronic job by and this came with a new coil.

Anyone have any ideas how I could. Diagnose and fix this problem?

 

[Firewout]

hi Pollard,
welcome to the forum.
you might reconsider the fuel problem.
it's typical behaviour of a blocked fuel filter or pick up pipe in the tank.
you can give a blast of air through the pick up pipe into the tank : at my LHD BJ46, there is a fuel separator, the line coming from the fuel tank goes into the top of it. It's at the outside of the left frame member.

 

[Ben Stratford]

+1 for what Firewout said. Has the fuel line been partially crushed anywhere too?

 

[Rodger]

I had very similar experience with my 40. Traced to the flex fuel line between the chassis pipe and the engine (pump feed) - they deteriorate inside - the pipe collapses inward restricting the flow of fuel. As the pump sucks the line restricts and when the engine stops it expands again. Fitted a new length of flex fuel line and it's never happened again and that was about ten years ago.

 

[Pollardd]

OK you have convinced me to check the fuel line.
I won't be able to get to this until the weekend.
I'd expect this fuel line to be 30 years old so it could very well be the problem.
Let's see if I can find a replacement online
I'll post again with what I find.
Thanks
David.

 

[Pollardd]

I tried to start The Limo this morning to move it from the shed to the workshop and it started but only run for about 10 seconds when it just stopped like I switched it off. Did this several times. So I now have to work on it in the shed.

I removed the fuel line from the filer to the pump and fuel ran out of the line.

I removed the filter and that is not blocked.
I blew on the line going to the tank and air easily went down the line so no blockage there.

I removed the return line going from the pump back to the tank and that isn't blocked either.

There is also a small flexible line going from the pump to the to the steel pipe that goes to the carbi.
That is in good shape as well.

So t think that is all the flexible lines and the filter covered.

I guess if it is still a fuel problem it is the fuel pump itself.

I wasn't game to try and start it straight away as there is a bit of dribbled fuel around. Not that I have changed anything yet.

Any suggestions what I should try next?
David

 

[Pollardd]

I tried to start The Limo this morning to move it from the shed to the workshop and it started but only run for about 10 seconds when it just stopped like I switched it off. Did this several times. So I now have to work on it in the shed.

I removed the fuel line from the filer to the pump and fuel ran out of the line.

I removed the filter and that is not blocked.
I blew on the line going to the tank and air easily went down the line so no blockage there.

I removed the return line going from the pump back to the tank and that isn't blocked either.

There is also a small flexible line going from the pump to the to the steel pipe that goes to the carbi.
That is in good shape as well.

So t think that is all the flexible lines and the filter covered.

I guess if it is still a fuel problem it is the fuel pump itself.

I wasn't game to try and start it straight away as there is a bit of dribbled fuel around. Not that I have changed anything yet.

Any suggestions what I should try next?
David

Update
I checked the sight guage on the carbi and the fuel was about halfway up before I started it and after it conked out. I also removed the air filter and looked down into the carbi. When I pump the accelerator I see the expected squirt of fuel.

 

[Rodger]

Ummm....
I still think it's the fuel system - maybe a sticking needle or the pump diaphragm or the in-line filter (less likely as you blew through the lines). Or it could be a low tension wire broken and only making intermittent contact but IMO this is less likely.

Regards,

 

[Pollardd]

I think the key symptom is that when the problem started the run time between failures was 5-10 minutes. This got progressively shorter on my way home until now it only runs for about 10 seconds.
I'll keep looking. I don't want to get it towed 15km into town to see a mechanic.

 

[Ben Stratford]

If you disconnect the fuel line to the carb and catch safely in a container - get assistance, what is the flow like when cranking?
What type of carb is it?

 

[clivehorridge]

Couldn't this be insulation in the HT coil breaking down?

Sorry I know nothing about 40s at all, but instant failure of a petrol, always triggers electrics in my head, either low tension, condenser /points for example or HT leaks...

The progressive reduced intervals suggest to me insulation failure...

Welcome to the forum BTW, almost forgot

 

[Rodger]

David,
This may be a long shot, but a friend in Chicago had not-dissimilar problems with his 2F, where the bi-metal heat valve unit shaft had ceased in the open position and that caused, or so I understand, the fuel to partially evaporate leaving insufficient to feed the engine. It had ceased where it passes through the manifold.
As you probably know the valve opens allowing hot exhaust gases to heat the inlet manifold and when everything is up to temperature it should close but if it doesn't....
IMO it doesn't account for the now 10 secs running but if it was stuck in the open position originally when the problem started but has now stuck closed as it is, in effect, a choke.
As Clive suggests it is worth checking sparks too.

Regards,
Rodger

 

[Pollardd]

Update,
I replaced the coil today. I had a bit of trouble figuring out which was the correct one. I figured it out in the finish and got a Bosch original.
Now the car starts and runs at idle. I can even put it in gear and coast around the paddock at idle speed. If I try and increase the RPM more than a little bit it stalls in gear or not. I'm still seeing fuel in the site guage about half way up all the time.

Thanks for all your suggestions. I'll try and work through them tomorrow. I don't think it is temperature related as it happens cold or hot.

Hope it doesn't turn into a tow job
David

 

[Ben Stratford]

I had the same symptoms in a motorcycle once which turned out to be a blocked airway in the carb. When applying throttle at all it would stall. But kicked over and restarted ok.
Had the carb cleaned at a local bike shop and all sorted!

 

[Pollardd]

If you disconnect the fuel line to the carb and catch safely in a container - get assistance, what is the flow like when cranking?
What type of carb is it?

I haven't tried disconnecting the fuel line at the carb yet. That process is described in the manual. The engine should run for 1 minute on a carburettor full. It is the standard carburettor from new. It would not have been changed.

 

[Pollardd]

I had the same symptoms in a motorcycle once which turned out to be a blocked airway in the carb. When applying throttle at all it would stall. But kicked over and restarted ok.
Had the carb cleaned at a local bike shop and all sorted!

I remember years ago seeing stuff called carburettor cleaner. You either sprayed or poured it into the carby. Used to smoke like a James Bond getaway which makes me think they may have banned it.
If it is still around does anyone think it may help?

 

[Pollardd]

Hi Guys,
I ended up getting "The Limo" towed to the Mechanic. I have been in the NRMA for a million years and I get up to 20 Km free towing so I thought I may as well take advantage of that. Distance to mechanic = 15 km
For anyone trying to diagnose the same problem I thought I may as well post the solution.

My electronic distributor was stuffed or at least a part in it was stuffed. As it wasn't an original unit there was no way to find replacement parts for it. So I found another new complete distributor online for $89.00 and had it shipped direct to the Mechanic. He told the unit was identical to the broken one. If not the same brand it is probably some generic thing that gets re-branded.

I'm off to pick her up this afternoon and I'm not expecting any trouble.
The old Distributor lasted about 8 years so I don't have two much to complain about

Just goes to reinforce that old saying.
Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.

David