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Lister JP3 timing problem.


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Can anybody help...I have a JP3m in my Narrowboat. After overhauling the engine I cannot get the timing correct and the engine wont run. The pump a CAV type is different to the manual and does not have the 'R' mark but a keyway so the only adjustment is on the Vernier adj. The engine just shows signs of life fully retarded on the adj ( lots of grey smoke) but wont actually run. I started at the spill point, the fly wheel is 23" then adjusted the vernier. 

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Are you sure you were using the correct spill point. I seem to remember there is long spill and short spill, I think but without digging out my technical library that you need short spill.

 

Been looking for the booklet I wanted but it seems that I have thrown it. Its generic inline pump spill timing and I think its to do with what is cutting the fuel off as you turn the pump (before connecting it to the drive). I think it shoudl be the top of the pumping element but you get a similar effect when the helix on the element uncovers the port and that will be a fair few degrees of cam movementyt out. Very happy to be told this is all wrong by someone who is sure.

Edited by Tony Brooks
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I posted on spill timing here:

The initial part of that post was Kelvin specific, but the how to do it section  is applicable to all cam operated jerk type fuel pumps I know of.  Sometimes the adjustment is shims or tappets  but the JP normally has the same flavour fuel pump as a Kelvin Model J so the adjustment is at the oldham coupling.

Remember "spill point" is that position when the fuel STOPS flowing through the element and you can only find that with the delivery valve removed.

If you cannot get spill right on the adjuster,  then you need to check first  that the  No1 cyl TDC mark on the flywheel is correctly placed and No 1 is actually on the top of compression stroke with the flywheel at the mark. ( Particularly with 3 cyl engines as they seem to sometimes acquire 2 or 4 cyl flywheels).   If that is OK then you need to check the fuel pump drive is correctly positioned.  It sounds as if it may be a tooth out somewhere.

 

As you say you have a non standard pump please can we have a picture of the pump  and the nameplate in case there is something special.

N

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Hi, checked No1 at tdc on comp stroke both valves closed. Timing mark on coupling matched to mark on pump body. Vernier mid point. Removed spring and valve from holder spill point located by turning fly wheel (23") back and forth. Refused to start after much fiddling fully retarded vernier engine now chasing starter but not running lost of grey smoke. Injectors creaking,  new nozzels.

Pump model Cav bpe 3b i think. label damaged. Photos file size too big not sure how to reduce.

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Pump looks like it should, though the delivery valve holders seem different to the usual CAV ones, but that is of no matter.  BPE3B is the right pump model too.

 

I think you may have missassembled the pump drive, with the drive gear one tooth out. 

Where is the flywheel timing  mark when the spill stops?

 

 There seems to be an alignment mark on the pump drive gear housing.  What is that for?  If that were lined up with the mark on the drive side of  the coupling and the other marks on the pump side of the coupling you should be nearer to where the engine says you need to be.  

 

N

 

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Hi, I havnt touched the drive gear for the pump unless you mean the drive  coupling (fibre thingy). The cam ,crank, and beveled drive are as it was when it last ran. The timing mark you refer to I made to assist me putting it back together. We have tried every spill position from full advanced to full retard in increments without any sign of life except as I described in full retard. Going to do a compression test next in case rings have stuck although I have put redex in. 

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The cotter pin bolt that holds the coupling to the engine drive was very worn and the nut split when I undid it. I have replaced this bolt with another now wondering if that has put the timing out. There is very little play in the coupling. It poss is a WW thread as I didnt have a nut to fit it.

We did try turning the pump cam 180 incase it was out that way but nothing. If compression test is ok we will have to start from scratch and or have pump overhauled by specialist.

Edited by Ianbruce
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Ok, sorry, I thought you had just overhauled the engine.

 

If the compression seems OK by hand, and the high/low compression valves are not leaking badly, it should start and run in this weather.  The timing is clearly out, but the pump insides cannot cause that, so no need for an overhaul of the pump yet.  Nor can I see any way for the cotter bolt to affect the timing, unless the whole thing has lost its key  engine side.

 

Worth checking that the pump is not 90 deg out. 

  Set the engine to TDC No 1, at the end of the compression  stroke. Remove pump.  

Connect up the fuel inlet and turn the pump in the normal direction until the No1 outlet spits fuel.  Hold pump in this position. Beware of the springs inside which will make it try to keep turning.  Reconnect the pump, moving the shaft the minimum possible to align.

N

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I recommend going on Thunderboat and asking Tony Dunkley.   I understand he's banned off here.  He's mentioned this thread and I have to say he's not too impressed by the advice you're getting Ian. ?

Edited by Joe Bourke
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My guess from your photos above is the injector pump is inserted in the vernier180 degrees out because in your pic there is a o stamped on the vernier (standard on one of these). there is normally a coresponding one on the injector pump coupling if its an original that will line up with this. so if you check the bit of the coupling that isnt visable in the photo and there is a o stamped then rotate the camshaft 180 and reinsert into the vernier with it aligned with the one on the vernier. from there you should have enough adjustment. If that doesnt work then see my comments below.

 

FB_IMG_1590781169811.jpg

 

Right, by overhauled your engine did you have the crank out or at least the cover at the injector pump end off?  If so then the below will be relevant or if the timing has been out for years as well. This also assumes you are spill timing it using the correct cylinder element on the pump. for a JP3 its the one nearest the drive end of the pump. and using a proper spill timing pipe not just the open end of pump delivery valve nut as that will only get you within several miles anyway.

 

The only adjustment on a JP is the vernier adjuster so if you cannot get the timing right using that you either have the pump engaged in the vernier coupling 180 degrees out or the drive to the pump is a tooth or two out. The second is only relevant if you have had the end cover off to remove the crank, or someone has and has got it wrong reassebling it. I have seen alot of JPs that are like this even what appear to be from the factory. Had one that was injecting at nearly TDC because it was out and another that even fully retarded on the vernier was injecting at near 40 degrees BTDC becasue the gear was out.

 

The way to get around it being a tooth out is a pain to do but easy if done whilst assembling. You need to set the crank so the injection mark is aligned whilst the injector pump drive shaft gear is disengaged from the crank (end cover pulled back, which will require the removal of the oil pump and drive and the flywheel if a marine engine).  Now with the crank set at the injection position for number 1.  if you now spill time the pump and when at spill mark the coupling and injector pump body with a pair of lines that match up when at the correct point. now with the vernier in the midpoint of its adjustment and the pump installed onto the coupling hold the pump with the lines matched and push the end cover in to engage the gear. if the marks on the pump move a little when you do this and the gears engage dont worry because this can be corrected with the vernier but if it moves alot then you will need to pull the end cover back out and try again. as soon as the cover is fully home you can now adjust the marks until your marks align spot on and you know the timing is close enough for final spill timing once the engine is fully assembled.

 

So if you are certain the spill timing method being followed is correct. ( Turning the engine/pump in the correct direction, cylinder ones element being used, have a spill pipe fitted, injector pump rack at max fuel, you are trying to time it on the correct side of the injector pump cam, element on its way up not down. if this is all correct and it needs more adjustment than the vernier can give then possibly the injector pump is engaged in the vernier 180 degrees out. if its not either of these then the injector pump drive shaft is incorrectly engaged with the camshaft and then you need to follow the above.

 

Hope this helps

 

Martyn

 

Edited by martyn 1
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There has been some mention of 90 degrees and 180 degrees but this is a three cylinder engine so the mistiming might more likely be a function of 120 degrees?

I also note that there seems to be a new delivery pipe and nut on the pump implying that these parts have been off the pump at some point which begs the question, are you SURE they went back on in the right order?

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2 hours ago, Joe Bourke said:

He's mentioned this thread and I have to say he's not too impressed by the advice you're getting

That’s TD’s style. He often criticises the advice given on here. Besides, spill timing HAS been mentioned. 

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18 minutes ago, Man 'o Kent said:

There has been some mention of 90 degrees and 180 degrees but this is a three cylinder engine so the mistiming might more likely be a function of 120 degrees?

I also note that there seems to be a new delivery pipe and nut on the pump implying that these parts have been off the pump at some point which begs the question, are you SURE they went back on in the right order?

And now think again it has bugger all to do with the 120 degrees between cylinders. the coupling between the pump and engine can be fitted together in two positions. one correct, the other the pump camshaft is 180degrees out from the engine. When you have reconditioned as many of these as I have then you might get it......

 

I would have to agree with the advice below, Those who have never had one of these to bits to the point to know how to properly diagnose an issue should keep there thoughts to themselves.

2 hours ago, Joe Bourke said:

I recommend going on Thunderboat and asking Tony Dunkley.   I understand he's banned off here.  He's mentioned this thread and I have to say he's not too impressed by the advice you're getting Ian. ?

 

Edited by martyn 1
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Just now, martyn 1 said:

And now think again it has bugger all to do with the 120 degrees between cylinders. the coupling between the pump and engine can be fitted together in two positions. one correct, the other the pump camshaft is 180degrees out from the engine. When you have reconditioned as many of these as I have then you might get it......

I rebuilt the top end of a Fiat X1-9 many moons ago and despite lining up the camshaft timing marks it wouldn’t start. An off-duty RAC chap I knew came and took a look. He asked “What’s that other mark on the camshaft?”  I replied “Dunno, but according to the manual the one I’ve used is the correct one.”  He pointed out that “... it wasn’t starting, was it? So let’s try the other one”.


It started straight away :)

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On 31/05/2020 at 13:19, martyn 1 said:

My guess from your photos above is the injector pump is inserted in the vernier180 degrees out because in your pic there is a o stamped on the vernier (standard on one of these). there is normally a coresponding one on the injector pump coupling if its an original that will line up with this. so if you check the bit of the coupling that isnt visable in the photo and there is a o stamped then rotate the camshaft 180 and reinsert into the vernier with it aligned with the one on the vernier. from there you should have enough adjustment. If that doesnt work then see my comments below.

 

FB_IMG_1590781169811.jpg

 

Right, by overhauled your engine did you have the crank out or at least the cover at the injector pump end off?  If so then the below will be relevant or if the timing has been out for years as well. This also assumes you are spill timing it using the correct cylinder element on the pump. for a JP3 its the one nearest the drive end of the pump. and using a proper spill timing pipe not just the open end of pump delivery valve nut as that will only get you within several miles anyway.

 

The only adjustment on a JP is the vernier adjuster so if you cannot get the timing right using that you either have the pump engaged in the vernier coupling 180 degrees out or the drive to the pump is a tooth or two out. The second is only relevant if you have had the end cover off to remove the crank, or someone has and has got it wrong reassebling it. I have seen alot of JPs that are like this even what appear to be from the factory. Had one that was injecting at nearly TDC because it was out and another that even fully retarded on the vernier was injecting at near 40 degrees BTDC becasue the gear was out.

 

The way to get around it being a tooth out is a pain to do but easy if done whilst assembling. You need to set the crank so the injection mark is aligned whilst the injector pump drive shaft gear is disengaged from the crank (end cover pulled back, which will require the removal of the oil pump and drive and the flywheel if a marine engine).  Now with the crank set at the injection position for number 1.  if you now spill time the pump and when at spill mark the coupling and injector pump body with a pair of lines that match up when at the correct point. now with the vernier in the midpoint of its adjustment and the pump installed onto the coupling hold the pump with the lines matched and push the end cover in to engage the gear. if the marks on the pump move a little when you do this and the gears engage dont worry because this can be corrected with the vernier but if it moves alot then you will need to pull the end cover back out and try again. as soon as the cover is fully home you can now adjust the marks until your marks align spot on and you know the timing is close enough for final spill timing once the engine is fully assembled.

 

So if you are certain the spill timing method being followed is correct. ( Turning the engine/pump in the correct direction, cylinder ones element being used, have a spill pipe fitted, injector pump rack at max fuel, you are trying to time it on the correct side of the injector pump cam, element on its way up not down. if this is all correct and it needs more adjustment than the vernier can give then possibly the injector pump is engaged in the vernier 180 degrees out. if its not either of these then the injector pump drive shaft is incorrectly engaged with the camshaft and then you need to follow the above.

 

Hope this helps

 

Martyn

 

Thanks Martin, I havnt had the end cover off so if it is a tooth out then it has always been that way. I dont have the tools or kit to remove the fly wheel and end cover. I am following advice from Tony Dunkley over on Thunder Boat. I have  tried turning the coupling 180 without joy there is no O mark on the other side of the coupling. Inside the pump, No1 pump as marked, rises on the cam on approach to the ignition mark and I set the spill point to the ignition mark . I have checked the No 1 Cylinder is at TDC when the mark on the fly wheel is in line with the line on the block and measured the distance to the ingition mark at 5 1/8". I shall try to set the spill at 4 7/8" I dont have a swan necked spill timing pipe so will try to us the pipe to the injector . I have used the nut method before when I renewed the key on the engine side of the coupling , must have been lucky I just checked it was ok and didnt need to adjust anything. I will keep trying.

Edited by Ianbruce
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Ok to get things straight, going back to your original post you said you had overhauled it, but you mention you havnt had the crank out so it sounds like it has had a top end freshen up? could you tell us what has actually been done to the engine since it last ran? as this will make the possibilities for the cause alot easier.  The JP's are an extreamly simple engine so there wont be much of an issue.

 

You say "No1 pump as marked" which concerns me a little.... Is this the element nearest the coupling on the pump? if not ignore the markings and use that one for the spill timing as that is correct for a JP.  yours being a JP3M no 1 cyl is nearest the flywheel and the pipes should be connected to the cylinders as shown below. Closest to block to cylinder 1, center to cyl 2 and furthest away from block to cyl 3. Im just wondering

 

100_2795.JPG.1e4149ab41ea85a38e1293f4261f0d6d.JPG

 

Edited by martyn 1
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Hi Martin, the plan was to change the oil, mop out the sump and tank, clean oil filter. Investigate why no3 cylinder was over heating. Clean fuel filter and address rust at the bottom of day tank caused by condensation/leaking roof at fuel filler. Pump coupling slack check key.

Took out day tank 1/4 " thick and surface rust no problem. Cleaned out furry stuff / bug and refitted. Fuel filter cleaned in paraffin and refitted. Removed water pump found slave gear off crank gear missing teeth, Crank ok. Think I spoke to you when searching for a new gear. Had a new one made. Water Pump appeared to have seized taken apart and freed off. ( didnt know you had to oil it in filler at rear the other end is fed from the engine) all refitted. No3 head water passages blocked by lime scale, disolved out , new gasket and refitted. Fuel coupling key ok pinch bolt nut had broken bolt replaced no slack in coupling when replaced.

Fuel system bled and primed tried to start no joy. Checked injectors 1 just dribbles, one not working,. Taken to injection specialist, 3 new  nozzels fitted and tested. Only thing I can think of is bits got in the fuel line. 18 months since last ran.

Having attemped to start I put some redex in each cylinder in case rings were stuck.

There is definately compression in each of the cylinders.

The elements on the pump are numbered as your photo shows. The numbers stamped into the pump body. No 1 element connects to the cylinder at the flywheel end, No2 to the middle one and No3 to the back one.

Further to your previous post I found the O on the coupling with some wet n dry. It is in the correct position although I have got the fibre thingy around the wrong way. So the O on it doesnt quite line up with the other two.

Further to my previous post I timed the spill cut off to 4 7/8" BTDC  having checked No 1 cylinder was at TDC when the stamped TDC 1 mark on the fly wheel was in line with the mark on the block. The spill cut off was about 6 inches advanced but adjusted back on the vernier.

Attempted to start engine, fired chasing the starter and lots of black smoke. But would not run. Tried misting easystart in front of air intake but this made little difference.

I know its a simple engine it can only be timing ,fuel or compression but I,m at a loss.

Thanks Ian 

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Hi Ian,

 

So as it stands now, every time you try and start it, it fires but wont pick up? Is that correct? If this is correct with all the cylinders decompressed and on each attempt of starting engaging a different cylinder each time is it definitly firing on all the cylinders or does one fire but not on the others?

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