The Fordson Tractor Pages Forum

Hi All

I’ve been readin*as much as I can and have learned a lot from the forums but I hope you don’t mind if I ask what may be some possibly obvious questions.

Background - this is my 2nd major but it’s always had a problem with starting. It will only start with the cold start button pressed, even if the engines been running for hours. When running it’s got quite a bit of white smoke but otherwise OK.
It also seems to leak diesel from the overflow on the bottom of the injector pump when it’s stood after being run.

So I decided the injector pump was part of my problems and before doin the research picked up a cheap(ish) reconditioned one.

The engine number is 1366835 and I had a heck of a job trying to find the timing marks on the flywheel but I I think i’ve found them although they look as if they have been hit with hammer for some reason.

So where I think it should be on the flywheel (reading all Brian’s posts) the timing mark on the existing pump is about 20mm away which if I’m right with the mark may explain the starting issues. The ew injector pump I have is a 70 but the one on already is a 75. Will it make a difference if I put a 70 injector on?

So do I replace the pump or try and adjust the timing? Doesn’t the leaking diesel means it’s worn inside ?

How do I adjust the timing ? I have not loosened anything off yet and I can see by rotating the new pump how the marks should line up but it does not look like it’s fastened together wrong.

Many thanks for any help offered.

I’ve just found an image of what the timing marks should look like (clear with stamped numbers) and that looks nothing like mine which seem very feint with no visable numbers so i’m Off back out to try and find them.

https://imgur.com/gallery/3yW8M4s

These are my timing marks or what’s left of them. Does anyone know what number they start at so I can try and work it out.

Have you tried slackening the pinchbolt next to the fuel pump and moving the coupling backwards and forwards to see if the smoke etc improves a bit?

Those timing marks on your flywheel look as though the flywheel is really rusty, are there any numbers visible on it?

Hi Nick

The coupling felt very loose. I’ve tried moving it and now starting is harder than before with more smoke. I’m not sure what the pinch bolt is pinching onto. Is it a round shaft ?

No numbers visible on the flywheel. I may try get some fine sand paper on it to see what can be seen.

Thanks

Paul

Hello, your engine serial number 1366835 is a mark 1 engine of November 1955 build.

This should have a Simms pump with 7.00mm diameter pump plungers,
model type SPA.4A.70S.

This pump should be timed to inject at 26 degrees BTDC.

The pump you have fitted, SPE.4A.75S, has 7.5mm diameter pump plungers. This type of pump was NOT originally fitted to your engine. This pump was fitted to the mark 2 engine starting at serial number 1425097, and also (with some modifications) to the mark 3 engine starting at serial number 1481091. In practice this pump injected the same amount of fuel over a shorter time period than with the SPE.4A.70S pump. This later pump should be timed to inject at 19 degrees BTDC for engines fitted with a steel cylinder head gasket ( as fitted to early Power Major), and 23 degrees BTDC for engines fitted with the copper permanite or composite gasket (later Power Major and Super Major).

The fact that you say that the current injection pump (which is the wrong type anyway) spills diesel from the overflow when the engine is stopped and the tractor parked up for a while is an indication of where your problem is. The pumping elements are worn and suffering from excess leak off and will not deliver sufficient fuel for starting unless the excess fuel button is depressed. However the reconditioned pump you have is the correct one for this engine, so fit that and time to inject at 26 degrees BTDC. That should sort it out.

Good luck!

Cheers for the information, it’s sort of what i’d hope for.

I’ll get the old pump off and the new pump on. The coupling seems very noisy and it may be just beciase it is loose so i’m Hoping it will all make sense as to how to adjust once it’s off.

A bit of luck that the reconditioned pump is actually the correct one.

I will try cleaning the fly wheel up a bit so I can see the marks

Thanks again

The couplings are noisy on the Major even when new. You can get a new replacement for the centre fibre/plastic section, although they are made of a different material these days with the new high duty plastics available. Most of the classic tractor parts suppliers have them, also on Ebay.

Just a thought - are the timing plate with the scribe line on it and the drive coupling flange already on your reconditioned pump? These have to be fitted at the diesel specialists who reconditioned the pump, as the timing of the pump to the drive flange scribe line and timing plate scribe line are set up on re-assembly of the pump when it is rebuilt.

Your flywheel is very badly rusted, all the scribe lines on the flywheel are at 1 degree intervals, at 20 degrees the scribe line is shorter with "20" stamped next to it, then there are 4 full width scribe lines before another shorter scribe line with "25" stamped next to it, then full width scribe lines again and so on. If you clean it up this might allow you to identify the 20 and 25 degree marks and so enable you to time the pump to 26 degrees.

Fix one problem - find another

I’ve swapped the pumps out, worked out the timing through the rust and bled. Sparked straight into life.

Now I have a leak at the bottom of the new pump. There is a plate on the lower section of the injector (tank side) and it’s weeping quite a bit. Does anyone know what’s behind the plate ans can I remove it and use some liquid gasket or will the insides spring out as soon as I remove the last bolt? I have loosened it as I assume it’s dried out in the hope tightening up later in the day once it’s soaked some diesel will fix it.

Many thanks for the help so far.

Paul,

Thats the bearing plate. You can remove it, but the camshaft cold fall down a bit. So I think you beteer work on it while the pump is vertical.
Cleaning and a new or liquid seal will do the trick.

Take a look at https://people.zeelandnet.nl/hmdetroije/ and find repairs page 5.

If you do this, work in a very clean area and cover things up, so no durt or dust can enter the pump.

There's always a risc, working on the diesel pump, so no garanties are made on the above.

Thanks Henk

I’m tempted but I may try find somewhere to send it. If I open up the old one I can see how problematic it looks like it’s going to be. I’ve already tried to open the old one up but I can’t get the cover off.

Many thanks

Firstly I am a little puzzled by the sequence of events here. Did you fit the replacement pump and time it up and fill it with oil by removing the 4 or 8 bolt side cover and fill until the oil ran out of the overflow pipe which determines the correct oil level? Or did you fit the pump and start up without filling with oil, so that what is leaking is oil that was already in the pump before you fitted it? Also is it oil that is leaking from the end plate or diesel that has leaked past the pump plungers? Also is the overflow pipe in place that maintains the correct oil level?

As Henk says this plate carries the rear roller bearing outer race for the pump camshaft. The problem is that there is always going to be some pressure on the camshaft (and hence the bearing and carrier plate) from the spring loaded pumping elements at whatever position the camshaft is in during it's 360 degree full turn. Even at the points of minimum pressure ( there will be 4 ), if you remove the plate there will be some camshaft "drop", and re-fitting the plate containing the race with a new gasket may be problematical.

You could try just undoing the bolts a couple of threads , prising the plate back a fraction (be careful!) so that the rollers are still seated on the outer race, leave the cambox to drain of all oil for a day or two ( leave it tipped it rearwards), wash the plate and the small gap with petrol and let it dry before trying to get some gasket cement into the gap all the way round the plate before tightening up the four bolts. Re-fit the pump and time up and add oil via the side cover until oil runs out of the overflow pipe to give the correct level. But if you are uncertain then better to take it to an injection service specialist.

I am surprised that you have this problem given that you say this pump has been "overhauled" or "re-conditioned". However you say the engine now starts and runs well so you are nearly there!

Hi Shepp

I acquired the reconditioned pump knowing there conditioning had been done some time ago and wasn’t warranted.

Given I had started messin with the timing on the old pump I decided to bite the bullet and remove it. The coupling was loose which I figured would be helping things so fitted the reconditioned pump and set the timing.

If i’m honest I forgot about the oil so what’s coming out is diesel. Should that happen with no oil and should I try filling with oil and will that stop the diesel leak?

The pump should be lubricated with pure diesel. Best to fill it up until the pig tail drips and than close the front plate.

If it is diesel coming out are you sure the leak is definitely from the back plate and not diesel from one of the injector unions or the input pipe into the pump from the filter that is leaking and the fuel is running down the back of the pump and appearing to come from the back plate?? If it is running continuously then it is more likely to be coming from a different source than the back plate, as to come from the cam box would require diesel to be continually leaking past the pump plungers, which is highly unlikely.

If it is definitely from the backplate then whether it is oil or diesel it will continue to leak until you fix the issue, so the answer is "no, putting oil in will not stop the leak". So you need to seal the plate somehow.

The official line from the Simms workshop manual after re-installing a vacuum governed injection pump is : ".....using a pump type oil can fill pump cam box to level of leak-off pipe opening with clean new engine oil then install leak-off pipe".
In other words remove the leak off pipe and banjo bolt and fill with engine oil through the hole that the bolt screws into until oil runs out, then re-fit the leak-off pipe and banjo bolt.
On the minimec pump there is a separate oil drain plug, a separate oil level plug and a separate oil fill plug, and the instruction again in the workshop manual is to fill with clean new engine oil through the filler plug until oil runs out of the level plug, then re-fit the level and filler plugs.

In use the oil will become diluted over a long period of time by diesel that escapes past the pump plungers, although the amount escaping should be minute in a pump in good condition.

Hi Shepp

I woke up thinking the same thing. Time to get back out and check those pipes.

Thanks

Paul

Shepp you are a star.

Fastened the cam plate up and found a weeping fuel pipe where it goes into the injector. Now i’m trying to tighten it up enough so it stops without stripping the thread. It’s pretty tight but still weeping - any ideas ? What I don’t know was if it leaked before which is entirely possible given the amount of diesel around everywhere. On the plus side it starts and runs (idle only so far) like a dream now and my new pump actually seems ok.

Thanks again for all your help, I’ve learned a lot this week.

Glad you found the problem.
New diesel lines are for sale.

Thanks Henk your assistance has been much appreciated.

Yes i’ve ordered a new fuel line, we’ll see how that goes. Ether than a new injector.

The olive on the injector pipe responsible will be damaged, as henk says better to order a new injector pipe.

Don't forget to top the pump up with engine oil as I said in a previous post!

shepp wrote:The olive on the injector pipe responsible will be damaged, as henk says better to order a new injector pipe.

Don't forget to top the pump up with engine oil as I said in a previous post!

shepp,

My 6pot is leaking Fuel on the injection pump where the leakoff pipe is fitted. It just has the banjo bolt and the first 2cm of the pipe, the rest broke off I think. What could be the issue on this?

Hi Mathias

If diesel is coming from the leak off shown in the lower right of the picture then it is most likely to be fuel that is getting past the pump plungers and barrels under pressure due to wear or scoring of these components. There will always be some fuel leak from the pump elements, that is why the leak-off pipe is there, but it should be a very small amount on a pump in good condition.

Are you having starting problems or power problems with the engine as Paul has had? This would give you an indication how worn the pump might be. You would have to weigh up how much fuel is being lost against any issues with the engine to decide whether to have the pump overhauled.

There is just one other thing comes to mind, the delivery valve holders have serrations on them and are screwed into the top of the pump body and are prevented from unscrewing by the 3 clamps held with "allan" screws. Under each delivery valve holder is a nylon sealing washer between the delivery valve holder and the delivery valve guide. I cannot really see how any problems with a damaged nylon washer or a loose delivery valve holder could allow any fuel to get into the cambox, but it might be an idea to check that none of the delivery valve holders are loose.

Hey shepp, this is turning out to be another of those archives of info not found in the manuals.

I happened to pick up my 'spare' pump to get to something behind it so took the spec off the plate to compare with your identifications above, it came off an old wrecker dad had years ago for some lift parts and he took this off before it went on its last journey and stood on a shelf for decades, I can't remember what the donor was but mine is an April 1958 Diesel Major - one of the 'silent upgrade' test tractors with Mk 2 engine (Number in my sig line), it is marked SPE 4A 70S 380 so I'm assuming I don't actually have a spare after all

Would you know what it was specified for ?

If not a Mk 2 I'm open to a swap with anyone with the reverse problem

It'll be interesting to see what the old girl is fitted with as it may explain why she refuses to start even hot without the cold start button being pressed, pulls like a train when running - goodness knows what other cut and shut jobs dad did with more enthusiasm than knowledge but I'll get her back to good order sooner or later.

Hey shepp, this is turning out to be another of those archives of info not found in the manuals.

I happened to pick up my 'spare' pump to get to something behind it so took the spec off the plate to compare with your identifications above, it came off an old wrecker dad had years ago for some lift parts and he took this off before it went on its last journey and stood on a shelf for decades, I can't remember what the donor was but mine is an April 1958 Diesel Major - one of the 'silent upgrade' test tractors with Mk 2 engine (Number in my sig line), it is marked SPE 4A 70S 380 so I'm assuming I don't actually have a spare after all

Would you know what it was specified for ?

If not a Mk 2 I'm open to a swap with anyone with the reverse problem

It'll be interesting to see what the old girl is fitted with as it may explain why she refuses to start even hot without the cold start button being pressed, pulls like a train when running - goodness knows what other cut and shut jobs dad did with more enthusiasm than knowledge but I'll get her back to good order sooner or later.

Hi Rick

Your spare pump SPE 4A 70S 380 is a later type pump for the Mark 1 engine with 7.00mm diameter pumping elements and fitted to the mark 1 engine from number 1308977 up to and including engine number 1425096. The pump prior to this was SPE 4A 70S 296 fitted up to engine number 1308976. Either pump will be correct for any mark 1 engine, just minor internal differences.

These pumps can be fitted to the mark 2 or mark 3 engine IN AN EMERGENCY, but the pump timing has to be altered to that for the mark 1 engine, which is 29 degrees BTDC for the SPE 4A 70S 296 pump and 26 degrees BTDC for the SPE 4A 70S 380 pump like yours. The reason for the need to adjust the timing is because the pumps with the 7.0mm diameter pumping elements fitted to the mark 1 engine take a slightly longer time to inject the same amount of fuel as the SPE 4A 75S type pumps with the 7.5mm diameter pumping elements which are fitted to mark 2 and mark 3 engines as standard. Hence the need to start the injection point slightly earlier.

So you could keep it for that emergency situation if it ever arises!

Kind regards.