The Fordson Tractor Pages Forum

!961 fordson dexta Rev counter broke so not 100% on the revs but have a few friends with dextas and they run rings around me i have taken the mushroom off while driving picks up a little speed but not what i would exspect compared to other dextas i have driven

I had a pneumatic Dexta with a perfect engine, but lack 'uuuoomph' and top end power. Tried everything, but when I pulled the fuel tank valve from the tank the reason was obvious. Fuel flow. When I got my fuel flow right, my top end RPMs were back.

A dirty air filter will result in the engine running slow, ensure that the wire mesh filters are not blocked and that the oil in the bowl is the correct grade and at the correct level.

Gerald

Is the throttle butterfly opening fully? Check your thottle rods.

It would be interesting to put a hand held tacho on the PTO to see what revs the engine is governed to.

PTO speed of 540 = engine speed of 1551
Therefore PTO speed x 2.87 = engine speed.
Full throttle should be 2000rpm engine speed = 696 PTO speed

Hi Gents, Very interesting topic. My 1959 Dexta is really slow. When attending road runs other drivers (including dextas) get annoyed at my wee Bella holding them up. I've actually decided to just pull over and head for home. All other tractors including FE35's FE TE20's seem to all be faster than my Dexta. Took it out yesterday and using two Sat Navs it read a top speed of 12 mph however the Tacho is reading 16mph.

Fuel lines are clear to pump. Air Cleaner is new with clean oil and filter in bowl. Butterfly is open fully at inlet manifold. All filters and fluids have been recently replaced. Is there anything I should be checking at the Simms pump/governors?

For the life of me I cannot figure out why this wee Dexta is so slow. As always I would love to hear from you guys (I am green I admit).

Wee59, you have the answer to your question. Your tacho has spent the last 50 years bouncing around paddocks and living in the rain. As you say it is not reading correctly, the dam things telling lies. Find somebody with a hand held tacho and put it on the PTO shaft, set the engine rpm correctly, and all will be happy. You will show those Fergies how its done on the next run!

pjjms Thanks for your reply. I know that the tacho is inaccurate, using GPS I have a top speed of 12mph. I reckon I have the butterfly fully open, could it be something to do with the governor? cheers

Yes, I believe you will need to adjust the governor. Google fordson manual and clich on the fordson .se result. Pages 65 and 81 are worth a look.

Just spent the day with the Dexta. Took it around this morning for a speed trial - 12mph. Brought Bella back to the garage. removed the pipe from the inlet manifold to the governor at both end and blew with an airline - free from blockages.
Checked the oil bath, filter clean and oil clean and at correct level.
Removed the fuel injector air cleaner gauze, not too bad, cleaned with paraffin and blew with air. Replaced, checked tractor RPM and no difference.
Then removed governor diaphragm housing, took out spring and inspected diaphragm, no obvious puncture marks or tears. Removed diaphragm and cleaned thoroughly of gunge etc. Cleaned the seal to make a good seal and replaced.
Started tractor and the needle filled the tractor meter to 2200 RPM!!!! Then took the Dexta for a run using the same sat nav to measure the speed. It reported a steady 17mph which it maintained up the steepest of hills

SO LOOK OUT FE35's and TE20's..........Next road run im coming to get ya!!!!!!!

P.S Also found out that if you remove the Air Pre Cleaner I can achieve an extra 3mph! Maybe it could be 'altered' somehow........lol

Wee59dexta wrote: SO LOOK OUT FE35's and TE20's..........Next road run im coming to get ya!!!!!!!

I really like that statement!! Everyone here would really like to to see something like that, isn't it? especially when the road run has to take a steep hill climb route then there's the time to outrun those rather nasty grey things!!

Wee59dexta wrote:Also found out that if you remove the Air Pre Cleaner I can achieve an extra 3mph! Maybe it could be 'altered' somehow........lol

But don't overspeed the engine...

Cleaned the seal to make a good seal and replaced.

Should the governor cover have a seal? I am having similar symptoms but there is no seal!

Thanks
John

My apologies there is no 'seal'. I thoroughly cleaned the housing to seat the diaphragm and make a good seal.

Took a 23c engine'd fe35 fergie for a spin after I'd rebuilt the engine. Found it to be rather slow even flat out in high 3rd. Much prefer the zippy feel of the dexta on the road

I think that you will find that the early Dextas have a higher top speed than the later ones. According to Sparex the ratios changed in August 1960 at SN 957E63953. My Dexta is June 1960 so great for road runs but lacks the flexibility in lower gears.