No revs!

[Tony Dunkley]

 

When the engine is warming up it is not producing as much power as at typical operating temperature, so when the alternator is working hard, and you do have a large alternator which was working hard, against a low battery bank this puts considerable load on and hence you will have less power available to pull away.

 

That is why the large hard working alternator is relevant as it reduces the power left to rev up the engine in gear. Any loss of power through partial fuel starvation etc will then be amplified. To be honest my view is just warm the engine up for 5-10 mins before you pull away and you probably will not see this again.

 

That's not good advice. His engine's telling him that there's a problem developing, and you're telling him how to use it in a way that will disguise the problem.

A diesel engine can produce full power when still stone cold immediately after starting, and if it won't, there's something wrong with it that needs fixing. Learning how to live with developing faults or problems, and hoping they'll go away, invariably ends up with a total breakdown, frequently at the most inopportune of moments.

[PeterG]

 

That's not good advice. His engine's telling him that there's a problem developing, and you're telling him how to use it in a way that will disguise the problem.

A diesel engine can produce full power when still stone cold immediately after starting, and if it won't, there's something wrong with it that needs fixing. Learning how to live with developing faults or problems, and hoping they'll go away, invariably ends up with a total breakdown, frequently at the most inopportune of moments.

 

I did previously suggest checking all of the filters for fuel starvation if you check further up the thread. I also know diesel engines do not produce usable full power immediately after starting and I know this from working for Lucas CAV in the past doing things which included cold and hot starts in special temperature controlled chambers. We had all sorts of instrumentation on these engines which proved that, it is not just from hearsay.

 

However good advice for Gardners is to warm up for a few minutes first, for all sorts of reasons, including the fact that Gardner themselves recommended it in their General Instructions book.

 

If I put my old CAV hat on then what could have happened is cleaning the sediment bowl for the first time in 15 years could have got some gunge into the system but equally if only seen the symptoms once and the OP did pull straight away with the conditions mentioned then that could explain the symptoms of a wearing setup but one that is still perfectly ok to use.

[by'eck]

A good squirt of fuel on each cycle. The lift pump has to be able to deliver more fuel than the maximum possible demand even at low rpm.

 

If there was no black smoke, it's definitely fuel starvation. I suppose it's possible that the fuel control bar/governor had stuck but more likely some sort of blockage. Even though you say the filters were changed fairly recently, if you have some diesel bug it can block things very quickly. I would drop the filters and have a look for any slime / sludge.

 

I had a situation once where the engine revs wouldn't rise above 1200 rpm - this with a relatively modern turbo-diesel. It was as though the throttle linkage had come loose since above a certain position there was no response whatsoever. You could hear no attempt from the engine to accelerate and certainly no extra smoke. Stuggled into harbour, I later dove on prop to find fishing net wrapped around it like a hairnet. Guess the sophisticated governer had tight feedback - it certainly had a black smoke inhibitor.

[nicknorman]

I had a situation once where the engine revs wouldn't rise above 1200 rpm - this with a relatively modern turbo-diesel. It was as though the throttle linkage had come loose since above a certain position there was no response whatsoever. You could hear no attempt from the engine to accelerate and certainly no extra smoke. Stuggled into harbour, I later dove on prop to find fishing net wrapped around it like a hairnet. Guess the sophisticated governer had tight feedback - it certainly had a black smoke inhibitor.

Certainly our Beta 43 never black smokes even when the prop is totally choked and it wont go above idle at full throttle. That is all part of the modern pollution standards. But the OP's engine is not quite in that league!

[Tony Dunkley]

 

I did previously suggest checking all of the filters for fuel starvation if you check further up the thread. I also know diesel engines do not produce usable full power immediately after starting and I know this from working for Lucas CAV in the past doing things which included cold and hot starts in special temperature controlled chambers. We had all sorts of instrumentation on these engines which proved that, it is not just from hearsay.

 

However good advice for Gardners is to warm up for a few minutes first, for all sorts of reasons, including the fact that Gardner themselves recommended it in their General Instructions book.

 

If I put my old CAV hat on then what could have happened is cleaning the sediment bowl for the first time in 15 years could have got some gunge into the system but equally if only seen the symptoms once and the OP did pull straight away with the conditions mentioned then that could explain the symptoms of a wearing setup but one that is still perfectly ok to use.

 

Of course it's good practice to warm up any cold engine before applying full load, but my remark concerning the power a cold engine can produce comes from (came from) Gardners themselves, but feel free to contradict the engine makers if you so wish.

You don't specify the make or type, direct or indirect injection, of engine on which you were involved with cold start up testing, but if they did exhibit a marginal reduction in power before getting up to temperature, that's nothing more than what would be expected from small, high revving, poor thermal efficiency when cold, automotive type engines, but certainly not from big capacity, direct injection engines such as Gardners.

It is quite possible that some muck was disturbed and found it's way into the fuel system when the lift pump sediment bowl was cleaned recently, but the inability to pick up revs described by the OP was a first occurrance and some considerable time afterwards, which suggests the onset of new and unrelated, developing fault which should be diagnosed and rectified.

The reluctance to pick up revs immediately after starting is not untypical of a small amount of air having accumulated at the highest point in the fuel system after the engine was last stopped, but if that was the cause, that is also something that should be investigated and fixed.

Edited November 23, 2015 by Tony Dunkley

[bizzard]

I went out to a boat with a Lister SR2 that wouldn't rev at all and would only tick over. There was something wrong with the governor, stuck or something, couldn't see it as they're totally enclosed on the end of the crankshaft, I got round it by shifting the throttle-stop sector plate which overrode it and allowed it to rev normally. The owner was very happy, but had to remember not to over rev the engine. I think it's still the same after about 10 years. I don't know what kind of governor that Gardner engine has or if it's accessible.

[Tony Dunkley]

I went out to a boat with a Lister SR2 that wouldn't rev at all and would only tick over. There was something wrong with the governor, stuck or something, couldn't see it as they're totally enclosed on the end of the crankshaft, I got round it by shifting the throttle-stop sector plate which overrode it and allowed it to rev normally. The owner was very happy, but had to remember not to over rev the engine. I think it's still the same after about 10 years. I don't know what kind of governor that Gardner engine has or if it's accessible.

 

It's totally enclosed on the end of the (inline) injector pump cambox.

[bizzard]

 

It's totally enclosed on the end of the (inline) injector pump cambox.

Ok Thanks.

[PeterG]

 

Of course it's good practice to warm up any cold engine before applying full load, but my remark concerning the power a cold engine can produce comes from (came from) Gardners themselves, but feel free to contradict the engine makers if you so wish.

You don't specify the make or type, direct or indirect injection, of engine on which you were involved with cold start up testing, but if they did exhibit a marginal reduction in power before getting up to temperature, that's nothing more than what would be expected from small, high revving, poor thermal efficiency when cold, automotive type engines, but certainly not from big capacity, direct injection engines such as Gardners.

It is quite possible that some muck was disturbed and found it's way into the fuel system when the lift pump sediment bowl was cleaned recently, but the inability to pick up revs described by the OP was a first occurrance and some considerable time afterwards, which suggests the onset of new and unrelated, developing fault which should be diagnosed and rectified.

The reluctance to pick up revs immediately after starting is not untypical of a small amount of air having accumulated at the highest point in the fuel system after the engine was last stopped, but if that was the cause, that is also something that should be investigated and fixed.

 

 

You have missed the point that Gardner recommended warming up first as I said which is written down in their documentation, I have seen a quote saying that the engine is ready to take up full load but it does and could not state it produces full power.

 

For information I worked with engines that ranged from large lorry units down to small automotive. It was great fun with some of the lorries that we tested as a unit and just the motive power of larger vehicles but they all would lack power early on be that naturally aspirated or turbo and supercharged. If you think about it the efficiency, friction, fluid flows etc of the moving parts and the flame front of the diesel any of the combustion chamber designs does change with ambient temperature. I used to have access to some quite amazing high speed pictures of this but not since I left.

 

However all of this is off topic and the OP is concerned about lack of revs but noone has even mentioned if the prop size is too large which could be another factor when the power is down due to temperature of engine etc possible fuel starvation, sticky governor, heavy loading from large alternator working hard and possibly waxing fuel and temperature has just dropped considerably?

[Tony Dunkley]

 

You have missed the point that Gardner recommended warming up first as I said which is written down in their documentation, I have seen a quote saying that the engine is ready to take up full load but it does and could not state it produces full power.

 

However all of this is off topic and the OP is concerned about lack of revs but noone has even mentioned if the prop size is too large which could be another factor when the power is down due to temperature of engine etc possible fuel starvation, sticky governor, heavy loading from large alternator working hard and possibly waxing fuel and temperature has just dropped considerably?

 

In a typical, medium to heavy, slow speed displacement vessel installation the torque/power absorbed by the propeller at minimum engine rpm is a small proportion of the torque/power the engine can put out at that rpm.

If the OP's propeller was 'oversized' to the extent that it could prevent the engine getting above idling revs when the propeller power curve is about as far away, down the vertical (power) axis on the graph, from the engine horsepower curve as it gets, you would expect him to have noticed this sometime previously in the 15 years he says that he's had the engine; big alternators and low temperatures notwithstanding.

While we're exploring the realms of marine propulsion engine fantasy, I would really love to hear your explanation of how you think an engine can accept full load when it isn't producing full power. Again, reference to a graph of propeller power versus engine horsepower will assist.

Edited November 23, 2015 by Tony Dunkley

[PeterG]

 

While we're exploring the realms of marine propulsion engine fantasy, I would really love to hear your explanation of how you think an engine can accept full load when it isn't producing full power. Again, reference to a graph of propeller power versus engine horsepower will assist.

 

It was the Gardner literature that states can accept full load which you appear to have translated to full power which is a fundamentally different thing. If you do not understand the difference then I make no further comment.

 

Please note that the same Gardner literature states " but a careful engineer will recognise that in all heat engines it is better practice to apply the load as gradually as circumstances will permit, especially after starting from cold."

 

Bottom line is that none of this is helping the OP, shall we move on and see how we can help now?

[Paul G2]

 

 

You have missed the point that Gardner recommended warming up first as I said which is written down in their documentation, I have seen a quote saying that the engine is ready to take up full load but it does and could not state it produces full power.

 

 

 

In post #18 the OP discloses that he always lets the engine warm up for five minutes, so that apparently is not a factor.

[jonesthenuke]

 

When the engine is warming up it is not producing as much power as at typical operating temperature, so when the alternator is working hard, and you do have a large alternator which was working hard, against a low battery bank this puts considerable load on and hence you will have less power available to pull away.

 

That is why the large hard working alternator is relevant as it reduces the power left to rev up the engine in gear. Any loss of power through partial fuel starvation etc will then be amplified. To be honest my view is just warm the engine up for 5-10 mins before you pull away and you probably will not see this again.

Whilst alternator load may be a factor, the potential load is low in relation to the horsepower rating of the engine (say 150A at 15V plus drive/alternator inefficiency, its all going to be less than 5HP? If the engine struggles with that additional load then the prop is too large or the engine is underperforming. The OP says its a 4LW, so should not be underpowered in a narrowboat. So is the prop/gearbox/engine set up OK ?? (I seem to recollect this is a new engine for this boat, based on previous posts).

[PeterG]

I did not notice it was a 4LW, that is very big if it is a narrowboat.

[swift1894]

Whilst alternator load may be a factor, the potential load is low in relation to the horsepower rating of the engine (say 150A at 15V plus drive/alternator inefficiency, its all going to be less than 5HP? If the engine struggles with that additional load then the prop is too large or the engine is underperforming. The OP says its a 4LW, so should not be underpowered in a narrowboat. So is the prop/gearbox/engine set up OK ?? (I seem to recollect this is a new engine for this boat, based on previous posts).

Just to clarify, it's a 40 ton barge and the 4LW's been in for 40 years.

Edited November 23, 2015 by swift1894

[bizzard]

Technically, you shouldn't cast off until your sure the engine is warmed up and running ok, you would certainly need to if putting to sea or in a strong wind or if there's a current running. You wouldn't attempt to take off in an aeroplane with a cold engine, or would you.

[Tony Dunkley]

Just to clarify, it's a 40 ton barge and the 4LW's been in for 40 years.

 

You haven't yet confirmed whether or not there is a clean and undamaged gauze screen in place in the lift pump sediment bowl.

[jonesthenuke]

Just to clarify, it's a 40 ton barge and the 4LW's been in for 40 years.

OK, I confused some of the posts.Sorry.

[swift1894]

You haven't yet confirmed whether or not there is a clean and undamaged gauze screen in place in the lift pump sediment bowl.

Haven't had time to look yet Tony. Currently job number 4 on my list?

Edited November 23, 2015 by swift1894

[Geoff Taylor]

Some very interesting reading here, assuming your fuel system is clear and air intake is not constricted in any way it would be worth checking the valve clearances, injector pump rack and the governor settings, my guess lies with the governor.

I have driven many different Gardner powered trucks and believe me none of them produce anywhere near full power until fully warmed up of which some take much longer than others especially the 8 cylinder 240 which actually used to cool down when running empty, we used to remove the cooling fan permanently on those models and this gave an extra 12/14 BHP !!.

I used to know an old guy that ate, slept and breathed Gardner and the advice he always gave was warm up gently, work them hard and don't linger too long in stopping them.

[Tony Dunkley]

Haven't had time to look yet Tony. Currently job number 4 on my list

 

I'll PM you my phone number, and if you'd like to call me when you're about to do it, I can talk you through what to do, and what to look for and check at the same time.

[jonesthenuke]

 

A substantial 'solid' squirt of fuel every two turns of the crankshaft.

Did the fine gauze screen in the lift pump sediment bowl get cleaned when the filters were last changed?

 

Thinking about this I am sure my lift pump (engine is circa 1960) does not have a gauze in it. I have a scanned copy of an old AMAL manual and the gauze appears to be fitted below the large brass inlet valve in the center of the fuel bowl and that did not look like it should have had a gauze.

 

Were some lift pumps not fitted with gauze filters (e.g the later ones) or am a really missing something?

 

I am not too concerned as I have a Delphi filter fitted before the lift pump and the Gardner filter on the engine between the lift pump and the injection, so this is more curiosity than anything else!

[PeterG]

As you have a modern filter before the missing gauze one that is largely redundant as all that could do was to stop quite large pieces of crud which your other filter would have already stopped.

[Tony Dunkley]

 

Thinking about this I am sure my lift pump (engine is circa 1960) does not have a gauze in it. I have a scanned copy of an old AMAL manual and the gauze appears to be fitted below the large brass inlet valve in the center of the fuel bowl and that did not look like it should have had a gauze.

 

Were some lift pumps not fitted with gauze filters (e.g the later ones) or am a really missing something?

 

I am not too concerned as I have a Delphi filter fitted before the lift pump and the Gardner filter on the engine between the lift pump and the injection, so this is more curiosity than anything else!

 

The valve seating screws upwards into the lower half of the pump body, and the gauze filter screen is held in place on that with a threaded retaining ring. The filter screen was very fine brass gauze and easily damaged or distorted when being taken out or put back in for cleaning, and it's not unusual nowadays to find them missing completely.

In the absence of a primary filter between the tank and the lift pump, the gauze screen was essential to stop muck getting into the pump valves and preventing them from seating properly, but if you have a primary filter before the lift pump there's no need for the gauze screen to be fitted.

If your lift pump has been repaired/overhauled at some time, it may have had some more recent non-Amal parts fitted. There are some Italian made repair kits on the market with hexagonal inlet valve seats that have no provision for fitting the gauze and the retaining ring.

Edited November 24, 2015 by Tony Dunkley

[crossley]

My first post on here, so here goes,

I don't think it's a fuel starvation issue this, as the op is reporting a loss of speed control, not misfiring or stumbling when clutching in.

A 40 ton barge with a 4lw will be likely swinging a fairly large propeller through reduction gearing.

It is possible that with a cold engine,cold engine and gearbox oil, shaft drag, a big alternator all sapping power it didn't on this occasion have enough torque to pull away.

It's not easy to de-prime a Gardner

Pump quickly as the fuel volume

Chambers above the pump elements hold a fair amount of fuel.

I would check that the air release vent screw on the filter housing is clear, it's a only a tiny drilling, and that the return line is clear.

With the engine running,crack open the vent plug (s) on the pump volume chambers till fuel appears.

Was the stopping cam fully withdrawn?

This would limit fuel rack travel and rpm too.

My money's on a sluggish governor action, if it's got cold congealed oil on it's sliding surfaces inside.

Check the oil supply to the governor by quickly removing the inspection plug with the engine idling, don't put anything in or near the hole as the governor weights are revolving just inside. Just have a good look inside with a good torch.

It should be throwing drops of oil out of The plug hole, not a massive amount, but have some rags ready.

Look down into the bottom of the housing and oil should be trickling in from the cambox. There is also a feed at the back, higher up directly onto the governor weights which is quite difficult to see. There is a plug at the rear inboard side of the governor housing for this feed.replace plugs when finished.

Many years ago I drove many Gardner 6lxb engined busses, and these too were gutless in the morning.

Remember how they used to " hunt" at idle when cold, this gradually getting less as it warmed up.

Going into work at 05.30 on garage duty and starting up 30 odd clapped out Daimler fleetlines and atlanteans ready for the drivers coming in. Thick grey smoke, watering eyes, your clothes stank of unburned fuel. A blast up the road and the grey smoke went blue, then by dinnertime was gone.

Gardners offered an upgrade kit of high compression pistons for lxb's to stop them gassing people at bus stops. But we still love them!