The Fordson Tractor Pages Forum

Hello I'm a new member, I've just bought a 1961 Super Major the engine only revs to about 1,400 I expected it to rise to about 2,000, should it get to 2,000 or am I expecting too much?

1800 rpm no load speed, 1600 rpm working speed, 540 rpm idle.
Check your air filter and intake passages are clean. If they are then check the rack in the injector pump for movement; to do this pull the stop lever fully back and see if the force comes down about half way forward. If this is fine set the speed on the manifold.
Sandy

I recently changed the diaphragm in my governor which has knocked about 1500 rpm off the top speed, have been waiting awhile in case it needs to soften up but getting fed up now and about to refit the original, beware aftermarket parts made in the land of verynear is my conclusion ;(

61 Super Major should have a mechanical governor. No fiddly diaphragm and air pipes.

The minimec appeared on 08B-756398, the second tractor of May 1962, however, the lift pump with separate sediment bowl appeared slightly earlier.
Sandy

Read but didn't absorb, thanks for picking that up Hywel

Thanks for that Billy 26F5, I made a small adjustment to the air intake butterfly valve at full throttle it is now vertical, I cleaned out the air filter which had plenty of grit in the bottom replenished with clean oil, but the mesh was clean, no grass or seeds much to my surprise. The engine stop as you mentioned is quite firm and requires a bit more of a pull than I expected, does this mean there may be a rack problem ? ie. not allowing enough fuel into the pump, restricted movement ? I've no experience with injection pumps. The engine under no load only gets up to 1,300 rpm. any advice appreciated.
John

A pic of the maximum fuel stop might help. Some are fiddled with and this is visible at a glance.
Here's Billy's one.

Sandy

To check that there is no problem with air restriction take off the air intake pipe at the inlet manifold, start the tractor and throttle up and see what revs can be attained.
If there is a big improvement then either the air cleaner is still restricted or the pipe from the cleaner to the manifold may be laminating and collapsing internally and restricting the airflow.

The next thing to check is if there is any fuel restriction. Firstly undo the fuel tank filler cap and check if that makes a difference, if the air bleed hole in the cap is blocked air cannot enter the tank and fuel will not flow out. If that checks out operate the lift pump by hand and slacken the left hand bleedscrew on the top of the fuel filter. Fuel should spirt freely out of here free of air bubbles and in good volume whilst the lift pump is being operated. If there are continuing air bubbles in the fuel that indicates that air is being drawn in somewhere between the fuel tank tap and the filter. This could be caused by a loose union at the fuel tap or at the lift pump. It could also be caused by a split diaphragm in the lift pump. If fuel flow is free of bubbles but poor volume that indicates either a blocked mesh filter which is on the end of the fuel tap inside the fuel tank, or a blocked mesh filter in the bottom of the lift pump which is accessed when the sight glass is removed. Again, it could indicate a split diaphragm in the lift pump, in which case fuel will also be getting into the engine oil - is the oil becoming diluted?
If everything is OK tighten the left bleed screw and slacken the right bleed screw on the filter and operate the lift pump by hand again. If the flow is poor that indicates a blocked fuel filter which needs renewing.
If the fuel flow is good from the right hand filter bleedscrew tighten it up and open the bleedscrew on the injection pump, which is the 1/2 inch AF bolt head on the face of the pump above the cover plate held by 8 bolts and operate the lift pump by hand again. If the fuel flow is good and free from bubbles then there may be an internal problem in the injection pump.
Clean off the injection pump thoroughly and remove the 8 bolts holding the cover plate on - try and preserve the gasket. You will see the fuel rack and the pumping elements. Signs of corrosion or contamination will indicate problems. Operate the fuel shut off lever by hand, this has the stop cable attached to it. You should see the fuel rack move fully to the right hand side as the lever is operated and when the lever is released the fuel rack should move fully back to the left under the pressure of the governor spring which is in the housing with 2 pipes on the end if the pump. If the rack cannot move fully to the left spray the rack particularly the ends and pumping elements with WD40 or penetrating oil and keep operating the stop lever backwards and forwards, you may have to manually move the rack to the left by hand to begin with. Keep spraying and operating the stop lever by hand until the rack moves smoothly and fully to the right and then moves smoothly and easily fully back to the left when the stop lever is released. If the rack can be moved by hand fully to the left easily enough but will not return fully when the stop lever is released this indicates a possible broken governor spring in the governor housing. When the rack is free enough replace the side cover.

If your tractor starts easily enough then the pumping elements should be good. It is most likely that your problem lies with the earlier issues referred to and not internally in the injection pump. Someone may have messed with the maximum fuel stop on the injection pump as Billy says but usually this is screwed out to allow more engine revs not screwed in to restrict revs.Let us know how you get on.

Have I missed something Shepp ? - I started going down the route you have just taken and was told this was a minimec pump ??

Hi oehrick

The answer is "yes", this is a 1961 Super with a vacuum pump, the minimec came in at 08B756398 May 1962.
JMD168 says he has adjusted the butterfly valve on the inlet manifold to fully open position, engines with minimec pumps do not have the venturi in the inlet manifold!

I must need different specs !

I'm getting to know the feeling!

The rack will only move fully back in excess fuel, expect it to stop with the stop lever vertical and the lever should be loose to the running position (no play in it though) press the excess fuel button and it should spring back to full delivery, pull the stop lever and about half way the button should pop out again.
I have seen a case of a screwed in max. fuel stop that had similar symptoms.
Sandy

I bought a new pre cleaner for my PM air cleaner from a supplier I`ve used for a few years. After fitting the engine lost 500 rpm and it looked like the fins on the underside were angled far too shallow, plus they were thickly caked in paint. Long story short they sent 3 replacements all with the same result. They said they have "sold hundreds without complaint" so I stuck a piece of flat bar up the fins and "adjusted" them to let more air in and it was back to normal. Don`t underestimate a lack of air! Dave

I remember reading somewhere the fins were the wrong way round on a repro pre cleaner, they are supposed to be angled to give a clockwise swirl seen from above, removing some of the dust on the two slits on the top. This repro one didn't work this way and so needed more air filter cleaning as a result.
I still don't understand how it can be so difficult for aftermarket spare companies to get things right when the design is already around and is the way it is for a good reason.
Sorry for being so critical of aftermarket spare companies in this post.
Sandy

Hello, following the instruction from Shepp, I found out I needed a new starter solenoid as all I got was a click when trying to start which could be embarrassing when away from home, ordered one and got it fitted. Inlet butterfly valve vertical, cleaned out the air filter filled with clean oil. Loosened the olive from the tank, fuel flows, loosened the olive on the lift pump, fuel flows, loosened the olive on the outlet of the lift pump operated the trigger fuel squirted onto the engine block, I'm sure it shouldn't be doing that so I ordered a new one and fitted it this morning. Opened the bleed screws on the fuel filter, inlet and out let (in turn) operated the lift pump until all the bubbles had gone, opened the bleed screw on the injector pump fuel flowed easily. My low revving engine doesn't seem to have fuel starvation problems. Took the cover off the fuel pump to take a look at the rack, it moves easily from side to side and springs back, slackened the adjusting screw at the end and noticed the rack moved a further 5mm, so I am assuming this was the problem, limiting the rack travel. I will start it up in the morning out in the drive and see how we go, that is if it stops raining !

After adjusting the stop screw to gain full rack travel the engine speed increased to 1500 RPM which is still short of the 1,800, I took the rubber pipe off the inlet manifold and started it up, 1,800 was easily reached the engine was speeding up to 2,00 RPM when I shut it down. The hose was flattened at the top with the bonnet touching it so air flow would have been restricted, a new hose will now have to be ordered, all being well that will sort the low engine revs problem.

Hi

Hope the new pipe sorts the problem out for you, taking off the air cleaner to inlet manifold pipe was the FIRST thing that I suggested you do! Sometimes they laminate and the inner layer collapses under vacuum effect when the engine is running and restricts the air flow, and it is possible that this is what is happening if the pipe had been damaged by the bonnet. When the engine is not running the pipe returns internally to it' s original shape so if you examine it all seems well when it isn't!

The maximum speed stop on the pump is set and sealed when the pump is set up on a calibration machine, so it is not usually a good idea to interfere with this. When you have fitted the new pipe then if you can still easily achieve 2000 rpm I would try to reset the stop to the original position. Paint on the screw might indicate where this was. If you then still have more than 1800 no load rpm then adjust the maximum speed stop screw on the inlet manifold to restrict the venturi opening until 1800 rpm is achieved. You can also check and adjust if necessary the idling speed with the minimum speed stop screw.