Lister SR2

[FadeToScarlet]

Helped a friend today, his SR2 is running really rough at first and misfiring.

 

It seems like an airleak into the fuel system, because it hunts and misses occasionally at first, then after an hour or so of running, it seems to settle down and fire smoothly.

 

This would I suppose be because after that time, the air is mostly purged from the system- but then, when the engine is switched off and cools, air is drawn back into the system.

 

We're going to have a look at the fuel system sometime soon, making sure all unions are tight etc., and maybe do a fuel filter change to make sure all the seals are present and correct and rule that out.

 

Are there any known places where SR2 fuel systems tend to come loose, if they've not been cossetted and polished and every nut and union checked regularly?

 

And also, do my thoughts about it being an airleak into the system sound roughly correct?

 

If that's sorted, next stage is to make sure the exhaust is sealed, and clean the cooling fins.

[PhilR]

Forget the exhaust and cooling fins. .. and I would be inclined to rule out *air leaks* too. They don't suddenly disappear after 1 hours running.

 

Check all fuel filters - make sure they are all clean, including the screen filter on the lift pump.

[Iain_S]

If there is a slight air leak, it would be possible for air to collect at a high point when the engine is not running, which could give the symptoms described. I agree about checking fuel filters, especially any that are fitted before the fuel pump. If they block, there is a greater chance of air getting in between filter and pump.

 

I assume the leak off pipes return to the tank, rather than the engine mounted filter, as on some installations? (If the latter, an air leak into the fuel line is not likely to improve with running!)

 

The fuel system on the engine itself won't leak air in; it will leak diesel out, as it's under pressure from the pump.

 

Iain

[Pentargon]

If there is a slight air leak,

 

The fuel system on the engine itself won't leak air in; it will leak diesel out, as it's under pressure from the pump.

 

Iain

Tomorrow I make my first acquaintance with a Lister SR2 which is why I'm reading here. Got a problem with the three posts someone might know the answer. Limited knowledge of diesel plumbing but I thought the suction side (from the tank to the pump) was more or less at athmospheric unless a clogged filter prevented the juice from sailing up? I thought the function of the pump was to pressurise and distribute the juice to the appropriate injectors so the right amount of diesel properly atomised hit the correct cylinder just before TDC. Have I got it all arseways so late in life?

Edited November 23, 2011 by Pentargon

[bizzard]

Tomorrow I make my first acquaintance with a Lister SR2 which is why I'm reading here. Got a problem with the three posts someone might know the answer. Limited knowledge of diesel plumbing but I thought the suction side (from the tank to the pump) was more or less at athmospheric unless a clogged filter prevented the juice from sailing up? I thought the function of the pump was to pressurise and distribute the juice to the appropriate injectors so the right amount of diesel properly atomised hit the correct cylinder just before TDC. Have I got it all arseways so late in life?

I think your thinking of the injector pumps ,two Bryce on an SR2,you mean the camshaft driven lift pump which sucks if you like fuel from the tank,this pipe is under vacuum because it has to lift fuel up the pick up pipe which is the depth of the tank, which if there are any air leaks at joints ect air will be sucked in and then be forced on into the filter unit and then on to the injector pumps and then under high pressure to the injectors.

Edited November 23, 2011 by bizzard

[springy]

In fact (unsurprisingly) it depends where you are in the system :-

 

on a typical system where you have

 

tank -> primary filter/water trap -> lift pump -> secondary filter -> injector pump -> injectors

 

When the engine is running any problems before the lift pump (suction side) may result in air being

 

drawn in (slightly below atmospheric pressure), problems after the lift pump (pressure side) will show

 

up as a leak, if the engine is not running then either is actually possible, but leaks before the lift pump

 

and air drawn in after is more likely.

 

 

 

 

If you have a gravity fed system (day tank) then leaks. (or air drawn in if there's a blockage).

 

 

 

 

Not quite sure with modern injector pumps where the "lift pump" is actually built in to the injector

 

pump but i would expect the same principle - anything before the pump may leak when the engine

 

is not running, and draw air when the engine is running, however as they are often "self bleeding"

 

you may not notice it.

 

 

 

springy

 

 

[Biggles]

If you continue to have problems I can highly recommend Calumn Plant in Wisbeach. They looked after my ST3 when it needed attention.

 

If you continue to have problems I can highly recommend Calumn Plant in Wisbeach. They looked after my ST3 when it needed attention.

[bizzard]

If its an old installation it probably only has two fuel filters, The little gauze one in the lift pump and the small micro filter (Crosland 489) on the engine,no water separator.

[Pentargon]

Thanks heaps Mr. Bizzard and Mr. Springy. Have not taken up my new boat yet as broker/marina and surveyor are still organising their dates. I'm learning loads from this forum. Much obliged for the trouble taken and the detail provided on all the posts particularly by our Bishop Stortford representative. some day in the dusty miller?

[Athy]

Pentargon, I have just noticed your "location" and am amused by it. As I'm married to an Essex girl I understand it perfectly.

[Pentargon]

Pentargon, I have just noticed your "location" and am amused by it. As I'm married to an Essex girl I understand it perfectly.

 

LOL it's op dest yerry from Sarfen. LOL

And I 'recognise' your name. Lovely town.

Don't tell me you might be from it?

Edited December 27, 2011 by Pentargon

[bizzard]

Thanks heaps Mr. Bizzard and Mr. Springy. Have not taken up my new boat yet as broker/marina and surveyor are still organising their dates. I'm learning loads from this forum. Much obliged for the trouble taken and the detail provided on all the posts particularly by our Bishop Stortford representative. some day in the dusty miller?

Yes i know the Dusty miller well.

I do a spot of sailing instruction at a lake at Stanstead Abotts during the summer and call in there on the way back sometimes.

[Athy]

LOL it's op dest yerry from Sarfen. LOL

And I 'recognise' your name. Lovely town.

Don't tell me you might be from it?

Up the estuary, yes.

I didn't know there was a town called Athy. Wot u mean?

[Pentargon]

Up the estuary, yes.

I didn't know there was a town called Athy. Wot u mean?

 

There IS a town called Athy and it is on a canal called the Barrow navigation. Wik "Athy Barrow"

[Pentargon]

There IS a town called Athy and it is on a canal called the Barrow navigation. Wik "Athy Barrow"

 

not sure if it's naughty to 'latch on' to an existing thread with an ever-so-slightly off topic enquiry? But when i see the exocets I'll duck. Pentargon is a 36' Springer with an SR2 firmly bolted so it is almost solid. The fuel pipes from the port side tank to the lift pump are 3/8" copper. They have no vibration coils but are slightly curved. My safety cert is coming up for renewal. Inspector says he'd prefer flexible hoses. Now I'm one of those strange people who only fixes things if they're broke.

 

Would I be pushing my luck if I asked the inspector to demonstrate how my existing pipes could fracture or to explain to me in simple one sylabble words why he wants me to fit flexible hosing?

[PhilR]

not sure if it's naughty to 'latch on' to an existing thread with an ever-so-slightly off topic enquiry? But when i see the exocets I'll duck. Pentargon is a 36' Springer with an SR2 firmly bolted so it is almost solid. The fuel pipes from the port side tank to the lift pump are 3/8" copper. They have no vibration coils but are slightly curved. My safety cert is coming up for renewal. Inspector says he'd prefer flexible hoses. Now I'm one of those strange people who only fixes things if they're broke.

 

Would I be pushing my luck if I asked the inspector to demonstrate how my existing pipes could fracture or to explain to me in simple one sylabble words why he wants me to fit flexible hosing?

 

My SR2 is on solid mounts (bolted through 1ins oak to Steel channel section). The fuel pipes are all copper without vibration coils. I have never been asked to fit flexible hoses by an examiner. My installation is 32 years old. I doubt if flexible hoses would have lasted that long!

[Albion]

not sure if it's naughty to 'latch on' to an existing thread with an ever-so-slightly off topic enquiry? But when i see the exocets I'll duck. Pentargon is a 36' Springer with an SR2 firmly bolted so it is almost solid. The fuel pipes from the port side tank to the lift pump are 3/8" copper. They have no vibration coils but are slightly curved. My safety cert is coming up for renewal. Inspector says he'd prefer flexible hoses. Now I'm one of those strange people who only fixes things if they're broke.

 

Would I be pushing my luck if I asked the inspector to demonstrate how my existing pipes could fracture or to explain to me in simple one syllable words why he wants me to fit flexible hosing?

 

My feeling is that it would depend on what length is unsupported. Copper can work harden and crack with constant vibration so if the pipe is very well supported then I doubt there would be a problem. If however it is free to vibrate (and you might not be aware of this at every harmonic throughout the engine rev range) then it could well be a problem and he is being careful as a cracked pipe on a tidal river isn't good news.

But, I am no inspector so he is the one who will be putting his signature to the certificate.

Roger

[Pentargon]

My feeling is that it would depend on what length is unsupported. Copper can work harden and crack with constant vibration so if the pipe is very well supported then I doubt there would be a problem. If however it is free to vibrate (and you might not be aware of this at every harmonic throughout the engine rev range) then it could well be a problem and he is being careful as a cracked pipe on a tidal river isn't good news.

But, I am no inspector so he is the one who will be putting his signature to the certificate.

Roger

If it was an old pipe I'd 'consider' changing it, but the brightness indicates it is quite new. (I've owned Pentargon only 3mts. and have come in from centuries on tidal) It's quite a short length 15" and as I said is somewhat 'curved' enroute. I was talking to Access hoses in Rugby and he said flexible hosing is the latest flavour for examiners. Harmonics is not applicable in this pipe. For that the pipe has to be very straight and very rigid, but I do appreciate your comments and am listening for others. I'm new to t'cut but have already experiencing professional rip-offs and incompetence in other areas.

[Albion]

If it was an old pipe I'd 'consider' changing it, but the brightness indicates it is quite new. (I've owned Pentargon only 3mts. and have come in from centuries on tidal) It's quite a short length 15" and as I said is somewhat 'curved' enroute. I was talking to Access hoses in Rugby and he said flexible hosing is the latest flavour for examiners. Harmonics is not applicable in this pipe. For that the pipe has to be very straight and very rigid, but I do appreciate your comments and am listening for others. I'm new to t'cut but have already experiencing professional rip-offs and incompetence in other areas.

 

I'm afraid to say that harmonics is a problem with any suspended unsupported structure, curved, round, square, whatever shape you name. Any structure can vibrate and flex given the right input frequency. They have to design tall buildings such as tower blocks and similar structures so that they don't oscillate under certain conditions of wind speed and flow so your pipe doesn't enter into that league. You wouldn't think that you could get anything like a tower block to vibrate would you? The thing is that you won't be able to tell what frequency that is under real conditions with your pipe. You may be lucky and your pipe configuration won't vibrate given the varying input from the varying engine revs but I defy you to tell me that you can guarantee that there will be no harmonic vibration. The age of the pipe won't have much to do with it either, it might extend the time to fracture but it won't stop eventual fracture unless there is no vibration present and you don't know that for sure.

Roger

Edited April 20, 2012 by Albion

[Nick1969]

Hi all ,

I have exactly the same thing happen with my SR2 (when it was runnin ) .When she first started she purred irregularly , after about 15 minutes she settled gown, but I had to keep the rev,s up ,some people tell me 'thats the way Listers are" others tell me I have an air leek in the system or rather a fuel leek which is allowing air in, anyway I hope it all gets sorted for you.

[Mick_B]

Just to add a quick note to the above. My SR2 had a problem with hunting also which turned out to be caused by the rack's on the injector pumps not being 100% free.

[FadeToScarlet]

Wow, forgot how long ago I started helping my friend on this!

 

Got everything reassembled on Saturday, and traced a very small leak to one of the copper washers on the side of the fuel filter. I was tempted to have a go at re-annealing it, but haven't done it, though I know it's possible. He's going to replace it, and see if that sorts it out.

 

Reassembled and tightened, it runs very smoothly at tickover, and is much more consistent at higher revs, much more so than before.

 

We took the boat out onto the flooded river to give it a good workout punching the flood stream, and that settled it down nicely.

 

Now we've got to sort out the silencer- it's much more of a collander and is held together pretty much with jubilee clips, exhaust paste, and metal sheets... he needs a new one.

 

Edit: I think it's an expansion box, more than a silencer, as I can't see any baffles or anything inside.

Edited May 7, 2012 by FadeToScarlet

[luctor et emergo]

Silencer? On an SR??

 

 

Shame on you )

[FadeToScarlet]

Silencer? On an SR??

 

 

Shame on you )

 

'Taint my boat.

 

It's more of a collander, anyway...

[the grinch]

Silencer? On an SR??

 

 

Shame on you )

 

i agree, ran my HA2 on a flexi exhaust poked out the engine room door for near on a year before i got the rest of the exhaust fitted!