Stalling lister

[RLWP]

7 minutes ago, Martinb said:

Thanks we will have a think if we can attempt it....Thanks for all your help and guidance 

If you don't feel confident, any good mechanic can do this job. And if it helps, we often take 'phone calls to help mechanics not familiar with the LH150

 

I've got a gearbox turning up next week diagnosed over the 'phone with a mechanic new to these gearboxes

 

Richard

[Arthur Marshall]

I don't want to argue with the experts, but wouldn't it be simpler in the first place to just adjust the idle stop screw (or whatever it's called - the bolt that adjusts where the throttle doofer stops when you move the lever back) so the engine runs a bit quicker in neutral?  It is certainly my experience, admittedly with an SR2 not a 3, that the engine runs slower once warm so that if you adjusted the idle speed when cold it stalled when hot.  Only took half a turn to raise the revs a bit and it solved the problem, and you don't need to dismantle anything.

[RLWP]

9 minutes ago, Arthur Marshall said:

I don't want to argue with the experts, but wouldn't it be simpler in the first place to just adjust the idle stop screw (or whatever it's called - the bolt that adjusts where the throttle doofer stops when you move the lever back) so the engine runs a bit quicker in neutral?  It is certainly my experience, admittedly with an SR2 not a 3, that the engine runs slower once warm so that if you adjusted the idle speed when cold it stalled when hot.  Only took half a turn to raise the revs a bit and it solved the problem, and you don't need to dismantle anything.

To be honest, Arthur, this could really do with something a bit more than diagnosis by internet forum. You are right, it could be something simpler

 

I must admit, yours is the first engine I have come across that runs slower when hot - how odd

 

Richard

[Arthur Marshall]

12 minutes ago, RLWP said:

To be honest, Arthur, this could really do with something a bit more than diagnosis by internet forum. You are right, it could be something simpler

 

I must admit, yours is the first engine I have come across that runs slower when hot - how odd

 

Richard

That what everyone says. But the blasted thing does.  I'm going to clonk the next person who tells me that Listers run for ever and never give you any trouble with a frying pan.  I admit the first twenty were fine, but it's made up for it in the last half dozen...

[AjW]

I could never find a happy tick over speed,the sr3 always seemed to run too fast, especially past moored boats, so I was constantly knocking it in and out of gear.  I dropped the tick over speed, but in weather like this it would stall when hot.  Brought it back up again a little bit and all was good. 

Edited May 6, 2018 by AjW

[magpie patrick]

9 hours ago, Arthur Marshall said:

That what everyone says. But the blasted thing does.  I'm going to clonk the next person who tells me that Listers run for ever and never give you any trouble with a frying pan.  I admit the first twenty were fine, but it's made up for it in the last half dozen...

My Lister has given me loads of trouble, but never with a frying pan 

 

If it were me (and it oft has been me) I'd want expert diagnosis and assistance - it may be the idling speed it may not. My extensive eexperience of gearbox and engine failure means I would probably want to hear how it stalls, does it just quietly die or does it shudder to a halt. Lutine had a brief period jammed in forward gear and attempting to change gear did the latter, whereas her final problem, that I wrestled with from Wilcot onwards, was gently expiring unless I kept the revs up

 

ETA Lutine has a Lister ST2 and LHR150 gearbox

Edited May 7, 2018 by magpie patrick

[Martinb]

Hi all.

 

Thanks for all your ideas and help.   To explain a bit more on the circumstances.   It tends to stall after running for a bit i.e when the engine is hot.  I do notice idle is slower then when first started.  It also will tend to stall when moving from either forward or reverse.  If i spend any time in neutral it will stall.  The only way i can stop it is by pushing it forward or reverse for a brief second but even that sometimes that doesnt help.  It doesnt always do it but more often than not.

 

It was suggested we may have the wrong oil in the engine.  We have 10/40.  This view tends to be divided. 

 

Hope this is helpful

 

Martin

[RLWP]

Your engine isn't sophisticated enough to notice the oil. We supply SAE30 which is slightly more viscous than your 10/40 but not enough to notice

 

Richard

[Tony Brooks]

Further thoughts.

 

Are your cooling air exhaust ducts leak free and as per Lister recommendations and vented to outside the hull?

 

Is there sufficient  air inlet venting?

 

On the fleet we found the SL4s did things like stalling etc when the cooling air exhaust duct leaked hot air into the engine room. We solved that by ducting cool air into the inlet manifold..

[Martinb]

We have venting to the outside through ducting to side vent.  The inlet is just a vent on the opposite side.

 

The ducting does sag and does look as though they are too big length wise.   Seeing others though this seems the norm

Edited May 7, 2018 by Martinb

[Arthur Marshall]

One guy who knows Listers told me that as long as you can feel the hot air being pushed out of the ducting you're OK.  Mine was original a canvas structure that used to leak a load of hot air back into the engine compartment under the cruiser deck, so it just got hotter and hotter in there till the engine decided it had had enough and stopped for a bit.  In weather like this I still sometimes have to run with the deck boards propped up to let the hot air out.

[Mad Harold]

On 06/05/2018 at 10:47, Arthur Marshall said:

If it's of any help, my SR2 tickover slows down when the engine warms up.  After various engineers had tangled with the engine and reset stuff, I've often had to adjust the tickover speed to make sure the engine didn't die in neutral.

Got a theory as to why an air cooled Lister's tickover slows when hot. On starting from cold,the air for combustion is drawn from the cool engine bay,but when hot, draws warm air from a now warmer engine bay.

Hot air is of course less dense than cold,and could explain this unusual behaviour

Light aircraft have a carburettor heat system to melt carb ice,drawing hot air from the manifold.When operated the engine revs drop considerably.

[RLWP]

36 minutes ago, Furness said:

Got a theory as to why an air cooled Lister's tickover slows when hot. On starting from cold,the air for combustion is drawn from the cool engine bay,but when hot, draws warm air from a now warmer engine bay.

Hot air is of course less dense than cold,and could explain this unusual behaviour

And inside practically every diesel engine is a governor who's job is to hold the engine at constant speed no matter what - changing load for instance. It's surprising how differently each cylinder can be running in an engine while the speed doesn't change.

 

Setting up a Petter twin involves varying the amount of fuel one cylinder gets compared to the other with the engine running. Say you increase the fuel to one cylinder, the governor will automatically reduce the fuel to the other while maintaining constant speed while you work

 

Slight variations in air density will be compensated for by the governor

 

Richard

[Martinb]

Quick update on our stalling.  We increased the idle and this seem to do the trick.   Great feedback though and thanks to everyone who commented....nice to know there is plenty of help out there.