The Fordson Tractor Pages Forum

I know that there have been previous posts about the tachos on the dexta but none of them answer what query I have and I know there is a wealth of knowledge on here which is great. My 58 Dexta that I am restoring wasnt fitted with a tacho when I got her. It is fitted with a Perkins engine with the Lucas CAV pneumatic governor pump which does not have a tacho drive and no tacho drive from the camshaft either. I have fitted a dynamo with a tacho frive on it which turns clockwise. Now from what ive read on previous posts the Dextas are fitted with anti-clockwise tachos. I am wanting to try and keep it original as possible as I want to show it once finished and have been told that this engine could quite possibly be original as there were a few variations of engines fitted for testing in the first Dextas that were produced. Is my only option available is to fit a tacho for a Major which is clockwise but with that it shows 7 gears, the PTO revs are different ( Not that I will be using PTO ) and also only goes to 2400 revs where as the Dexta one goes to 2600 revs. Appreciate any advise.

First problem, you have NOT got a Perkins engine it is a Ford engine built by Ford at Dagenham and assembled by Perkins. Sorry to be pedantic but this is a common error and, if you order parts for a Perkins you will find a lot of them will not fit. That is, unless your tractor engine has been replaced, then it is not original.

Dexta rev counters, for some reason, do not show all the speeds in all the gears. The place to go for parts or reconditioning is Speedograph Richfield who have all the original data for making and repairing rev counters for all the range. Not cheap but far better than the ones available from other suppliers. The rev counter drive should be from the rear of the injection pump. Bear in mind that not all Dextas were fitted with a tacho from new, it was an extra on the early tractors.

Brian many thanks for the info but im rather confused now. I have been told from one source that I have a P3.144 Perkins conversion pack fitted, another source told me that it is a P3.144 as Dextas were never fitted with Lucas CAV injector pumps. Also another source who worked for Ford for many years away back said that it could be an original engine as with my Dexta being an early one #274 off the production line Ford fitted a few different variants of engines for trials. What is confusing as well I was told that Dexta engine #"s started 14 and Super Dextas started 16 where as mine starts 11. Also when i came to rebuild my engine all parts that i had to order were for the F3.144 engine i.e. crankshaft,shells,liners,oil pump, pistons, cam followers,valve guides and valves etc. There is no tacho drive on the injection pump as you will see from the pictures that is why i have went down the road of fitting a dynamo with a tacho drive. It would be nice to know exactly what i have so if you or anyone can shed some light on it I would appreciate that.

Then you could have a prototype Dexta.

Ford made the cast parts for Dextas at the foundry in Dagenham as part of the agreement with Perkins. Perkins only did assembly work and they were the first company as far as I know to use the "just in time" method of manufacture. Cast parts were sent up the A1 on trucks to Peterborough and finished engines returned on the same lorries to the assembly line. Any parts that Perkins did cast, like the large timing gear had to have the Perkins badge removed.

Ford changed injectors, pumps, rear main seals and oil pumps. The Dexta dry sleeves are press fit too. The P3 engine had pintle type injectors rather than the nozzle type used in the Dexta and the Dexta sump will not fit a P3.144. The Dexta oil pump is not the same as the Perkins P3 and those pumps have to be modified to fit.

Ford specified Simms pumps and injectors because they were already using that brand on the Majors, this meant that the engine front plate and timing cover had to be re designed to take the new injection pump which was different to the P3.144. CAV and Simms were all owned by Lucas. P3 engines also used a timing chain not gears until quite late in their life. The parts book only lists one injection pump from 11/1957, the dates of the first production Dexta.

So it looks like you have a very rare tractor indeed with an engine that is a hybrid. More pictures would be very interesting. Casting codes and Serial number would also be interesting.

We do have a board member who owns Dexta number 27, I think, but that one has the "normal" Simms pump.

Brian very interesting information and thanks very much. It would be interesting if i could find out even more so I have posted pictures of the engine casting numbers and the tractor casting numbers. I have had the tractor casting numbers and the serial number verified by Patrick Pawsey as Jan and Feb 1958 who was a great help as I have registered it for the road already and been given an age related number even though I still have quite a bit to do to get it completed.

I have enlarged the picture of the prototype Dexta that I have, although blurred it may be a different pump to normal on her.

This is very interesting, your block was cast by Ford on November 21st 1957 according to my information, the 957E number on the gearbox is the mould number but this looks stamped in rather than from the mould itself. She really is an interesting tractor and should be the centre of attention at shows.

Brian,
Many thanks for the information again. You certainly are a wealth on knowledge. Here was me thinking that the engine had been changed at some point which I was a bit disappointed to be honest but to find out that it could be a protoype and was cast in Nov 1957 makes it very interesting. After looking through some more information it is certainly a Ford block as it has MONOCYL stamped on it and not a Perkins as I had previously been informed which is great news. Im unable to make out your picture clearly of the protoype but will have a search on the good old interweb to see what it can come up with. Going back to the tacho question it looks like with it being a prototype that there should be no tacho fitted. If that's the case I will change the dynamo back to one without a tacho drive and make sure that the position for the tacho on the dash gets a nice blanking plate fitted. Many thanks for your help.

It is great to read the wealth of knowledge in this forum, and I've enjoyed reading these posts. My Dexta is stamped 957E186 on the gearbox which I believe is early 1958. Mine does have the tacho drive on the fuel pump though which doesn't help the original poster.

Bluebilly its a fantastic forum and definately full of a wealth of knowledge. Great to know you have a very early Dexta as well,pictures would be nice. Ive all my pictures on photobucket from when I bought her right up to the stage im at now. You can see them on photobucket just look for charliesdexta.
Brian the picture you posted of the prototype. Did you mean that it was a picture of a prototype Dexta which you actually own or is it just a picture of a prototype?? If you own one I would be very interested to see more pictures if possible. Another dilema now before i start painting it is what colour should my dexta be if it was a protype?? Were they a green colour with red wheels or should I paint it Empire blue with orange wheels. Ive probably started another debate now. Ive posted a couple of pics before the start of my restoration as well. Thanks Charlie.

No, I do not own that tractor just the pictures taken from an early Ford film. Degradation of the film gives the green colour, they were Empire Blue with Empire Blue grills and Orange wheels.

It is a pity the picture is not clearer of the pump because from what I can see when it is blown up, it is not a Simms pump. The picture was taken on the Elveden Estate near Thetford in Norfolk on the Ford Test Farm that was part of the estate.

Over the years Ford did a lot of "mock up" tractors for test. One of Stuart Gibbards books show Super Dexta publicity shots of Super Dextas with vacuum governors. They were never fitted in service it was just that Ford wanted some Super Dexta pictures before production started and just put Super Dexta tinwork on a couple of Dextas. That is why you take all pictures in sales literature with a large pinch of salt.

Brian, many thanks for clarifying the colour to paint her. Ive had a look at your picture and it isnt the same pump that is on mine but cant be clear what it is as mine has the stop arm on the side as well. It would be very interesting to see if there are any pictures of Dextas available from testing on Elveden Estates but it could have been closed doors and very few pictures available. Many thanks for all the information again as due to this im starting to build up a little bit of history on her.

Hi Charlie63
Here is a photo of my dexta, it will be getting a new lick of paint over the winter now that I finished all the mechanical work.
This is my first attempt at posting a photo so I hope it works

BlueBilly,

Im unable to see the picture of your Dexta.

Charlie.

Trying again to upload a photo Charlie.. Hope it works this time

VERY NICE!!

Cracking looking Dexta there Bluebilly.