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Old cav injection pump setup


billybobbooth
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As above I've got about 3-5 pumps about all engines ran ok on them but will be doing full rebuild on them,

At £150 a pop just to have them checked after rebuild there must be a system or kit etc for setting them up.

 

I understand how they work and know how they adjust etc I also know some have collar setup marks on for the internal shafts.

 

I get to far moved around and they will put in different fuel amounts, I understand the rod and how it twists the internals to alow more or less fuel threw at different set positions. Given you can buy all new internals does anyone know the bit of kit I need to set them up.

 

I'm in the middle of getting a good injector tester to setup these after full rebuilds, and yes some pumps I can just exchange for a rebuild pump at £70 for lister ones but as I'm going to be doing a few I would much rather buy the kit I need.

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1 minute ago, billybobbooth said:

As above I've got about 3-5 pumps about all engines ran ok on them but will be doing full rebuild on them,

At £150 a pop just to have them checked after rebuild there must be a system or kit etc for setting them up.

 

I understand how they work and know how they adjust etc I also know some have collar setup marks on for the internal shafts.

 

I get to far moved around and they will put in different fuel amounts, I understand the rod and how it twists the internals to alow more or less fuel threw at different set positions. Given you can buy all new internals does anyone know the bit of kit I need to set them up.

 

I'm in the middle of getting a good injector tester to setup these after full rebuilds, and yes some pumps I can just exchange for a rebuild pump at £70 for lister ones but as I'm going to be doing a few I would much rather buy the kit I need.

 

Yes a Hartridge pump test bench but you won't want to pay for one. i think they will now cost thousands. You need to drive the pump to carry out two procedures. First phasing that ensures the injection starts at the correct degrees apart do for a four cylinder that will be every 90 degrees of pump rotation. Then calibration that ensures each pumping element delivers the same amount of fuel at any given rack position. The ones I am familiar with used sparks from a rotating pointer onto a degree ring to do the phasing. Once you have the Hartridge machine you can set up and test all the other types of multi cylinder pumps as well although some may need adapters.

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You can buy the internals, (except camshafts for BPE pumps.).  The main pumping bits (with the rotatable helical groove) you need are called  the elements. You may also find you need delivery valves and holders.  All on E bay of you have the part  numbers.  The elements come in various diameters.  The size you want is one of the numbers in in the fuel pump part number.  It varies in position with fuel pump type. The olddiesels website used to have the details or there is a CAV Booklet on how to parse fuel pump numbers.

 

Tony has said it all about the set up kit.  A Hartridge bench, or clone,  is the only way to go. Never seen one for sale second hand.  You really also need a clean room to keep it in.

 

It takes a deal of time to set up a fuel pump with more than one element.  That is why it costs so much.

 

N

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Sweet cheers guys ill have a look, I don't mind the time but 5×150 is 750 so at a few 100 extra ill have a look, I'm not desperate but thought it was worth looking into.

 

I've got all the internal part numbers, for all the bits and I've got hopefully a spare full pump on the way (stupid covid has prevented me from getting up to York for a day trip out)

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Yes I'm getting the feeling I can rebuild them but not test them accurately enough, I could rig something up so I can test a good one the setup a rebuild one doing several different tests of flow at different rates of pump arm length but getting an accurate enough gauge is very difficult as your talking next to no flow at each pump, pumping the pump isn't a problem as I can rig up a way to pump the pump just not measure its output

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20 minutes ago, billybobbooth said:

Yes I'm getting the feeling I can rebuild them but not test them accurately enough, I could rig something up so I can test a good one the setup a rebuild one doing several different tests of flow at different rates of pump arm length but getting an accurate enough gauge is very difficult as your talking next to no flow at each pump, pumping the pump isn't a problem as I can rig up a way to pump the pump just not measure its output

The way Hartridge do it is to connect the pump outlets to special "injectors" venting into a set of calibrated glass tubes. The "injectors" are fitted with some kind of electrical contact that reacts to the injection pulses and that is what triggers the sparks.

 

Those glass tubes are in pairs on either side of the rotating metal plate so one set is always upside down. You run the machine and watch the fuel build up in the tubes. its easy to see which needs more or less fuel so you sop the rig, adjust the elements and turn the tubes over so the full ones drain and the empty ones are ready for use. You do this countless times until you get each element delivering the same amount of fuel.

Edited by Tony Brooks
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34 minutes ago, Tony Brooks said:

The way Hartridge do it is to connect the pump outlets to special "injectors" venting into a set of calibrated glass tubes. The "injectors" are fitted with some kind of electrical contact that reacts to the injection pulses and that is what triggers the sparks.

 

Those glass tubes are in pairs on either side of the rotating metal plate so one set is always upside down. You run the machine and watch the fuel build up in the tubes. its easy to see which needs more or less fuel so you sop the rig, adjust the elements and turn the tubes over so the full ones drain and the empty ones are ready for use. You do this countless times until you get each element delivering the same amount of fuel.

Yes this was my understanding, I can do it in a sim way but I can't find and accurate enough digital reader, I have a fully recalibrated injector so I can test it from injector or directly out the pump but the only accurate gauges I can find are diesel leak test gauges (already have a set) but its not an easy task to connect to the injector nozzle or pump, was hoping to find a digital gauge I could connect to the pump and read it threw the pump

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3 minutes ago, billybobbooth said:

Yes this was my understanding, I can do it in a sim way but I can't find and accurate enough digital reader, I have a fully recalibrated injector so I can test it from injector or directly out the pump but the only accurate gauges I can find are diesel leak test gauges (already have a set) but its not an easy task to connect to the injector nozzle or pump, was hoping to find a digital gauge I could connect to the pump and read it threw the pump

I don't understand that. You don't measure flow rate or the individual injection pulse volume. You compare the volume delivered by each element with all the others and adjust until they are the same. I also don't understand  why its not easy to connect injectors to the pump, it just needs (probably longer) injector pipes made up. I am sure calibrated test tubes are easily available from scientific glass wear suppliers. I am sure and set of injectors will do but perhaps set the break pressures low. However calibration is the easier part. Its the phasing that I think will be difficult.

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I think you miss understood or me not explaining properly, its not a problem putting injector onto pump or activating the pump, its getting my calibrated diesel leak off pipes onto the end of the injectors or if I could find one getting an accurate flow gauge so I could fit a gauge to each output of pump to measure the output amount of fuel to then adjust.

I have a copy good pump so each one I know what the flow rate should be at a set point of the arm,

 

Due to cost of a machine I was hoping to put a inline flow gauge between each injector and the pump, and then also test how much fuel I had in each tube after the injectors. Again I can or will have calibrated injectors so thats not a problem,

 

As there old push style pumps they will all have the same min and max stroke on the pump.

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19 minutes ago, billybobbooth said:

I think you miss understood or me not explaining properly, its not a problem putting injector onto pump or activating the pump, its getting my calibrated diesel leak off pipes onto the end of the injectors or if I could find one getting an accurate flow gauge so I could fit a gauge to each output of pump to measure the output amount of fuel to then adjust.

I have a copy good pump so each one I know what the flow rate should be at a set point of the arm,

 

Due to cost of a machine I was hoping to put a inline flow gauge between each injector and the pump, and then also test how much fuel I had in each tube after the injectors. Again I can or will have calibrated injectors so thats not a problem,

 

As there old push style pumps they will all have the same min and max stroke on the pump.

 

Calibrated leak off pipes !!!! Just direct the injectors into test tubes calibrated in mm or 0.5 mm or whatever. I suspect you will have to lower the injector break pressure though so they dribble rather than atomise. Forget trying to measure less that a pin head of fuel with flow meters.

 

Is that so? As you phase by shims or adjustable tappets to move the element plunger up or down a tad I would suggest they will not have the same stroke.

 

Look find some images of a pump test bench in use and then it just might be a bit clearer for you. I still don't see how you will phase the elements though even if you can calibrate them.

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The pumps have a calibrated line into a slot i can a make a lever to fit and adjust under them like the stock push rods do so I can then get the same stroke from each pump.

 

I might not be able to so I may end up having to send them off, but as I have 5 I can play with one or 2 and see what happens, but I couldn't find a tool to do it but as you gave me this info above I've then looked and won't be able to buy one lol.

 

Hence seeing if there is a semi easy solution, as said I have a good untouched pump I can also test to see what this gives me, I also have old fuel pipe so I maybe able to create something to flow into my leak off containers.

 

I did look at pics which is why I've thought of a way I can make the pump pump.

 

As said if its not possible it will all have to be sent off once rebuild

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1 minute ago, billybobbooth said:

The pumps have a calibrated line into a slot i can a make a lever to fit and adjust under them like the stock push rods do so I can then get the same stroke from each pump.

 

I might not be able to so I may end up having to send them off, but as I have 5 I can play with one or 2 and see what happens, but I couldn't find a tool to do it but as you gave me this info above I've then looked and won't be able to buy one lol.

 

Hence seeing if there is a semi easy solution, as said I have a good untouched pump I can also test to see what this gives me, I also have old fuel pipe so I maybe able to create something to flow into my leak off containers.

 

I did look at pics which is why I've thought of a way I can make the pump pump.

 

As said if its not possible it will all have to be sent off once rebuild

You need one "old pipe" for each output connection on the pump  so probably four plus and injector and calibrated glass test tube for each output.

 

Stock push rods? Normally the cams push on roller cam followers which in turn push on the element via the phasing adjustment.

 

Still can''t see how you can phase them though, especially if the cams or followers are a bit worn.

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My plan was to put them on a bench with a frame over which the pumps will sit on and is clamped to the frame.

 

Under the frame ill put a leaver system in so it has an adjustable push rod that sits onto the bottom of the pump and attached to a lever, ill then have a stop point so the lever can't pull the adjuster away from the bottom of the pump and ill then use the gauge on the pump so when I pull the lever down it pushes the pump plunger in and have a lower adjustable stop point on the lever so each lever can be set to the same stop point on each pump, this way will insure each stroke is exactly the same (in theory giving each injector the same amount of fuel once adjusted)

 

Ill set this up using a good untouched pump the put on a pump thats been messed with. Ill set up an adjuster on the fuel adjustment rod so I can test the pump at say 4 pre set intervals, fully off, fully open and 2 set points in the middle.

 

If I use your idea of making the fuel pipes drip into a calibrated glass after say 10 strokes of each I can see which injector pump needs adjustment comparing that to the good pump I first tested.

 

Most of my pumps are either singles or a double pump (the doubles run as indervidual pumps but in a double housing) and the cam for them is build into the engine not the pump.

 

This way I can have a idea of how much fuel each pump should give out for a set stroke using the gauge on the pump itself even with a bit of wear the line on the pump can still be matched on each pump, with a pre set amount of throttle, ill then match each pump to a good pump.

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What are you talking about? individual pumps like many Listers use or a CAV inline pump with multi elements.

If its individual pumps then they are normally set up on the engine. They are usually timed with shims under the body and this is somewhat like phasing. The calibration if that is what it is is done by adjustable links between each pump aligning marks on each pumps control rod (rack). I don't think the pumps need setting up off the engine at all.

 

The phasing and calibration is needed to allow for variations in the cam, followers and other parts so if the cams are in the engine it all needs doing on the engine, not on a test bench.

 

If its an inline pump then the cam housing is below the pump so I don't see how you can possibly operate the individual elements by a lever from below - there's an alloy casting in the way. At last you tell us its not an inline pump.

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You must be able to set the pump up without being on the engine otherwise you would have to send your engine off when you have a pump calibrated if you sent it off. You normally have a set gap or point the pump is adjusted to on the engine, my engines have adjustable push rods and the instructions give a state as to where the pump marks should start from and go to.

 

I would send pic but I can't get one as I'm unable to get to the engine.

 

As my pumps are being fully rebuild every part new except housing and the rod, they would need all parts adjusting hence I need a good untouched pump to get the settings from as I won't be able to just adjust 1 tooth on rack it will need adjusting on the brass bit the rod moves.

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Not specific to your engine but the general principle.

 

The adjustable push rods (or shims) time the pump by moving the element up or down so if by chance the element was a bit low or high in the housing the pushrod adjustment would take this up. You need to set the ENGINE to the correct timing position so its camshaft is where it should be for each pump. You also need to set  the individual racks to the specific position, usually marked by a line on the rack that is aligned to the pump body. Then adjust the pushrods or shims while providing the injector pump with a supply of fuel. The delivery valve has to be removed and he housing refitted while doing this. I always used a swan neck of old injector pipe to see when the element just sealed the flow from the pump but some people look at the meniscus in the delivery valve holder. This then is the start of injection. Repeat for the other pumps. Now you have all the pumps starting injection at the correct time.

 

Having done that you need to get each pump's element twisted to the same  degree so the links between the individual pump racks are adjusted for length so the timing marks on the individual racks are all in the correct position.  This does means that when you assemble the pump you have to get the rack and element it the correct position relative to each other but I would expect witness marks.

 

I suspect I am misunderstanding something or have never come across you particular engine set up.

Edited by Tony Brooks
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Yes, we're both on the same lines as to how to time it,

The timing marks for a pump stroke is normally in the manual, I know mine should be at tdc the line right at the top of the window and bdc should be at the bottom of the window think one of the engines should have a 1mm gap at the top. Realise this must be set on the engine as is on rods or some have shims.

 

But if the pump isn't setup I could have 1 injector pumping correct fuel and other too much or to little, Ill have to do this off the engine by making a bench tester so in a perfect world if I get the pumps the same then put on engine aslong as the gapping at timing is done correctly both injectors will see the same fuel and a given rpm

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Hence why I wanna use a good pump so I can semi set the rebuild pump up as on a bench it doesn't matter when the timing is as long as the amount of fuel is the same at a given rack position.

As originally I was hoping to use a proper bit of kit for this but I'll have to make a home build one.

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1 minute ago, billybobbooth said:

Yes, we're both on the same lines as to how to time it,

The timing marks for a pump stroke is normally in the manual, I know mine should be at tdc the line right at the top of the window and bdc should be at the bottom of the window think one of the engines should have a 1mm gap at the top. Realise this must be set on the engine as is on rods or some have shims.

 

But if the pump isn't setup I could have 1 injector pumping correct fuel and other too much or to little, Ill have to do this off the engine by making a bench tester so in a perfect world if I get the pumps the same then put on engine as long as the gapping at timing is done correctly both injectors will see the same fuel and a given rpm

 

This is the bit I don't understand. I still can't picture how your pumps are linked control rod wise. I assume each pump has its own control rod/rack with perhaps 3/4" sticking out each side. If not I can't see how they can be set up so all deliver the same amount off fuel. To do that you need to adjust the link pieces between each pump and the last pump and governor so that the elements are all in the same position. As I said one side of the part of the rack that protrudes from the pump side normally has a line machined into it that needs to be aligned with the edge of the pump body so as long as the marks on all the pumps line up when you fit the rack links each pump will inject the same amount of fuel.

 

If your racks have no marks then I feel you could make your own by removing the delivery valve and replace the holder. then supply fuel to each pump and move the rack until fist fuel flows and back again until it stops. That shoudl be the start of injection.

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1 pump is a twin pump (1 single long rack) the other is 2 indervidual pumps with the rack bolted together,

As I'm stripping the completely the brass part the rack runs on won't be set into the correct position on the barrel, if the rack is fully to the left the brass part might be in a different position to the other. To set this up there is normally a dot on the brass bit and the barrel this brass bit goes onto but for some reason my new parts don't have this, that means if the rack is moved fully to the left (shut off) it might not be shut off, adjustment of the timing isn't going to fix this the pump needs to be set in the correct place first. This is what I have to set on the bench first.

If I copy a good pump I can set this into the right position. If its in the wrong position I could end up with over or under fuel compared to each other.

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I understand that final set up of timing etc on the engine was done by measuring exhaust gas temperature  at each cylinder. Large engines have thermometers at each cylinder port permanently fitted to facilitate this. A bit of a task on a 16cylinder engine with individual pumps!

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