Jp3 injection pump cam

[sparrowcycles]

Hello folks, 

As I can't go home for Xmas I'm thinking of checking the cam on Prince's injection pump. The engine runs really well, almost no smoke, good oil pressure etc but I'm not convinced that he has the power I'd expect from a Jp3 (well, JS3 really) when I bough him there was no oil in the pump sump so I thought I'd have a look at the cam. 

Does anyone have any tips for doing this? 

 

Many thanks! 

 

S

[frangar]

6 minutes ago, sparrowcycles said:

Hello folks, 

As I can't go home for Xmas I'm thinking of checking the cam on Prince's injection pump. The engine runs really well, almost no smoke, good oil pressure etc but I'm not convinced that he has the power I'd expect from a Jp3 (well, JS3 really) when I bough him there was no oil in the pump sump so I thought I'd have a look at the cam. 

Does anyone have any tips for doing this? 

 

Many thanks! 

 

S

My not very helpful advice would be to send it to a pump specialist who has the kit and parts to do stuff with it should it need it! However I think my go to company for this sort of thing may have retired! 
 

looks like he did. Here’s a link that might have some helpful info 

 

https://www.stationaryengineparts.com/peter-slater-fuel-injection-engineers-data-archive/

 

ive got a manual for the bpe pump if you want to send me an email via DM. 

Edited December 22, 2020 by frangar

[sparrowcycles]

4 minutes ago, frangar said:

My not very helpful advice would be to send it to a pump specialist who has the kit and parts to do stuff with it should it need it! However I think my go to company for this sort of thing may have retired! 
 

looks like he did. Here’s a link that might have some helpful info 

 

https://www.stationaryengineparts.com/peter-slater-fuel-injection-engineers-data-archive/

 

ive got a manual for the bpe pump if you want to send me an email via DM. 

Thanks, I'm normally the sort of person who will do the work themselves, it is one of the things I like about older engines, that with a decent workshop one can take on a lot of the work oneself. 

I'm not so naive, however, in pursuing this at the expense of my engine. I may well look for a good pump to test Prince with and go from there. 

 

S

[frangar]

8 minutes ago, sparrowcycles said:

Thanks, I'm normally the sort of person who will do the work themselves, it is one of the things I like about older engines, that with a decent workshop one can take on a lot of the work oneself. 

I'm not so naive, however, in pursuing this at the expense of my engine. I may well look for a good pump to test Prince with and go from there. 

 

S

Email sent.....best of luck! Let us know what you find out!!

[BEngo]

1 hour ago, sparrowcycles said:

Hello folks, 

As I can't go home for Xmas I'm thinking of checking the cam on Prince's injection pump. The engine runs really well, almost no smoke, good oil pressure etc but I'm not convinced that he has the power I'd expect from a Jp3 (well, JS3 really) when I bough him there was no oil in the pump sump so I thought I'd have a look at the cam. 

Does anyone have any tips for doing this? 

 

Many thanks! 

 

S

To get the camshaft out is a  full pump dismantle.  So, unless you can do the phasing checks and the  volume balance checks, which need something like a Hartridge test bench, leave well alone.

 

You can check well enough by fitting an " as new" injector to each outlet in turn and, whilst turning the engine over by hand or starter motor,  checking that on each outlet the injector gives a good even spray pattern, creaks evenly and  does not dribble.

If you are short of power it may be that the elements in the pump are the wrong size and too small.  The BPE pumping element is available in 5mm 7mm and 10 mm diameters IIRC and two  of the pump serial number digits tell you which size it should be.  I can't  at present lay my hands on the serial number parsing instructions but think it may be the first two after the  BPE3B bit.  They are on the web so Google should be able to help, or try the late  Peter Forbes website.  Actually checking what size you have is a specialist job because you need to dismantle the pump.

 

Replacement BPE camshafts are like Santa's reindeer poo  gold plated.  You may have to obtain a complete pump if you actually need one.  It does not sound like you should from your description of the way the engine runs.

 

N

[Tracy D'arth]

Best diesel guy I know is Wilkinsons in Reddish Stockport.

 

http://r-wilkinson-diesel.edan.io/

 

Never let me down with any diesel repair.

[BWM]

1 hour ago, sparrowcycles said:

Thanks, I'm normally the sort of person who will do the work themselves, it is one of the things I like about older engines, that with a decent workshop one can take on a lot of the work oneself. 

I'm not so naive, however, in pursuing this at the expense of my engine. I may well look for a good pump to test Prince with and go from there. 

 

S

Good pumps are hard to find, i know of at least one engine restorer that had many engines laying around requiring pumps.

  What leads you to think it lacks power? I'd be inclined to suspect the prop or pump timing before the cam, a lack of oil may actually indicate that the pump is in decent shape as many tend to fill with diesel due to wear of elements, etc.

Bengo has given some top information above, especially element size as the JS will require the larger size and may have been fitted with an older pump containing the small ones.

Edited December 22, 2020 by BWM

[Tony Brooks]

34 minutes ago, BWM said:

Good pumps are hard to find, i know of at least one engine restorer that had many engines laying around requiring pumps.

  What leads you to think it lacks power? I'd be inclined to suspect the prop or pump timing before the cam, a lack of oil may actually indicate that the pump is in decent shape as many tend to fill with diesel due to wear of elements, etc.

Bengo has given some top information above, especially element size as the JS will require the larger size and may have been fitted with an older pump containing the small ones.

and if its the type of pump I suspect it uses roller cam follower so I would expect wear in/on the roller or pin rather than the cam - that's if its worn to any significant extent at all.

[sparrowcycles]

On 22/12/2020 at 10:01, BEngo said:

To get the camshaft out is a  full pump dismantle.  So, unless you can do the phasing checks and the  volume balance checks, which need something like a Hartridge test bench, leave well alone.

 

You can check well enough by fitting an " as new" injector to each outlet in turn and, whilst turning the engine over by hand or starter motor,  checking that on each outlet the injector gives a good even spray pattern, creaks evenly and  does not dribble.

If you are short of power it may be that the elements in the pump are the wrong size and too small.  The BPE pumping element is available in 5mm 7mm and 10 mm diameters IIRC and two  of the pump serial number digits tell you which size it should be.  I can't  at present lay my hands on the serial number parsing instructions but think it may be the first two after the  BPE3B bit.  They are on the web so Google should be able to help, or try the late  Peter Forbes website.  Actually checking what size you have is a specialist job because you need to dismantle the pump.

 

Replacement BPE camshafts are like Santa's reindeer poo  gold plated.  You may have to obtain a complete pump if you actually need one.  It does not sound like you should from your description of the way the engine runs.

 

N

Thanks for that information, I'll see if I can check what elements are in the pump, the number is BPE3B700400/66533 as far as I can tell which might indicate a 7mm element. Of course I have no way of knowing if it's the correct pump. 

 

 

[sparrowcycles]

On 22/12/2020 at 10:39, BWM said:

Good pumps are hard to find, i know of at least one engine restorer that had many engines laying around requiring pumps.

  What leads you to think it lacks power? I'd be inclined to suspect the prop or pump timing before the cam, a lack of oil may actually indicate that the pump is in decent shape as many tend to fill with diesel due to wear of elements, etc.

Bengo has given some top information above, especially element size as the JS will require the larger size and may have been fitted with an older pump containing the small ones.

It's only that I steer a few of the coal boats which have much smaller engines than the JS and they can really really throw some water out the back when wound on a bit which Prince rarely does. 

Prince does have a 24" prop which is a bit small really but still.. 

I am aware that I may be looking too hard at something which isn't a problem, it's pretty shallow up here and he is pretty deep as well as having a very different shaped swim than other GU motors, all of which could affect it. 

 

Given that he runs smoothly with almost no smoke and good oil pressure I'm inclined to think that the injection timing is alright and the injectors working properly but I might see if I can try another pump just to put my mind at rest. 

 

 

[BEngo]

Have a look at oldengine.org on the  CAV Injection pages.  Applications data page 3  lists the pump which should be fitted to a variety of elderly engines.  For the JP3 it suggests a BPE 3B 75 W 400.  That is a 7.5 mm diameter element.  

 

Ths pump you have fitted is thus not the "correct" one,  if you believe the label, but you at least should have the correct stroke (10 mm).  The question now is whether you actually have a 7mm element or whether a 7.5 mm one has been fitted without  changing the number on the pump.  Only a specialist strip down will tell you that, but being 'down on power' is consistent with having an undersized element.  The difference is between 135 mm3 at max stroke i for 7mm dia and 160 mm3 for 7.5 mm dia.   That is almost a 20 % power reduction.

 

N.

[James Owen]

...and back in the real world.... 

 

A 24" blade married to a JP/S3??? 

 

Really, even at 1:1? 

[BWM]

12 hours ago, sparrowcycles said:

It's only that I steer a few of the coal boats which have much smaller engines than the JS and they can really really throw some water out the back when wound on a bit which Prince rarely does. 

Prince does have a 24" prop which is a bit small really but still.. 

I am aware that I may be looking too hard at something which isn't a problem, it's pretty shallow up here and he is pretty deep as well as having a very different shaped swim than other GU motors, all of which could affect it. 

 

Given that he runs smoothly with almost no smoke and good oil pressure I'm inclined to think that the injection timing is alright and the injectors working properly but I might see if I can try another pump just to put my mind at rest. 

 

 

Two things at work here, the first being the prop - 24" is a long way from the ideal, even with an extreme pitch. Mine is 27×22 and that is an inch smaller than optimum as i elected for the extra clearance being of more value, but on a royalty...

 The second is likely down to boat/engine design, as i suspect the shallower counter on a small boat would allow a bigger flume of water to blast out being nearer to the surface, and that a two cylinder engine is more often used at a higher rpm under similar conditions, i doubt i could push the tiller round at high rpm powered by my Jp3!

[sparrowcycles]

13 hours ago, BEngo said:

Have a look at oldengine.org on the  CAV Injection pages.  Applications data page 3  lists the pump which should be fitted to a variety of elderly engines.  For the JP3 it suggests a BPE 3B 75 W 400.  That is a 7.5 mm diameter element.  

 

Ths pump you have fitted is thus not the "correct" one,  if you believe the label, but you at least should have the correct stroke (10 mm).  The question now is whether you actually have a 7mm element or whether a 7.5 mm one has been fitted without  changing the number on the pump.  Only a specialist strip down will tell you that, but being 'down on power' is consistent with having an undersized element.  The difference is between 135 mm3 at max stroke i for 7mm dia and 160 mm3 for 7.5 mm dia.   That is almost a 20 % power reduction.

 

N.

Great, I'll have a look at that site, thanks! 

 

12 hours ago, James Owen said:

...and back in the real world.... 

 

A 24" blade married to a JP/S3??? 

 

Really, even at 1:1? 

Yes! It does have an extreme pitch (and pronounced prop walk to boot), a 28x20 is required I believe. 

 

2 hours ago, BWM said:

Two things at work here, the first being the prop - 24" is a long way from the ideal, even with an extreme pitch. Mine is 27×22 and that is an inch smaller than optimum as i elected for the extra clearance being of more value, but on a royalty...

 The second is likely down to boat/engine design, as i suspect the shallower counter on a small boat would allow a bigger flume of water to blast out being nearer to the surface, and that a two cylinder engine is more often used at a higher rpm under similar conditions, i doubt i could push the tiller round at high rpm powered by my Jp3!

True, as soon as he is out of the water I'll be swapping the prop. I do believe also that the town class boats swim allows more water to the propeller easily due to its steeper vee shape rather than the rounded barrel shaped swim on Prince. 

 

I will investigate the pump and let you all know when the prop is changed.