The Fordson Tractor Pages Forum

With the governor on a petrol Dexta, do they give problems? Now that I have got my Dexta up and running, I have two problems , 1, it idles too fast at 800/900 rpm as it seems to be held up by the governor, 2, as you open the throttle, the engine speed does't increase as progressively/smoothly. Has anyone else had these problems or any other problems with the governor? Also what are the valve clearances for this engine. The engine seems to be running much better, the more it gets used and much easier starting than the diesel.But needs more work done to it before it can be used properly as it has not had much "R and M" , for a month of Sundays, but what do you expect from a running petrol Dexta that cost less than GBP 200? TSG.

Mine idles poorly as well but I think thats a carb issue and does not seen held by the gonenor. Throttles fine as well.
For data like valve clearances I have found nothing under petrol dexta but there is plenty available for petrol feries and the dexta uses the same 89mm bore Standard motor Co engine as the 35 and 135 fergies. Bareco.com.au has some service data (under MF parts listing, tach specs) but they list valve clearances as inlet 12 and exhaust 8 thou, which seems back to front to me. I set mine to inlet 8 and exhaust 12 and it seems fine.

Hi guys,

There is a downloadable Petrol Dexta manual on this site and a similar one on Stephan's.
It shows valve clearances of inlet .010" (.25mm) and exhaust .006" (.152mm).
They were set backwards on ours and does run smoother after resetting them.

I also have trouble setting the idle. Wants to too run high (~1200) and can be lowered a bit by wiggling the throttle shaft and also does not throttle up smoothly.
It has too much play in the throttle shaft and leaks air in. Now looking for a kit containing a new shaft.

I had a chance to view a Petrol previous to its sale and the owner (an old mechanic) screwed the idle down so it was just ticking over at 200rpm! (I have a ways to go!)

For some reason the generator bracket was too tight to the engine, rubbing on the governor linkage and I had to space the bracket out with a couple of washers.
Have not noticed that trouble on other Petrol Dextas.

Also still looking for a workshop and parts manual for the engine.
Anyone ever seen one????
A Dexta service letter mentions a special supplement to the workshop manual for the Petrol and in the Dexta parts manual it refers to another manual for Petrol engine parts so they must be out there.

May our idling improve!
Les

I've never seen a petrol Dexta, but I have seen this problem on other gas engines with governors. They will idle too fast because of the throttle shaft leak that Les mentioned, then someone will try to "fix" it by adding a spring to the linkage between the gov. and the carb. That causes the gov. to not work correctly and the engine won't throttle up.

I havn't done anything to the governor yet, but have reset the valve clearances, as Les has posted, inlets at 0.010" and exhasts at 0.006", which does make a improvement on how it runs.(Much smoother than the 35 petrol up the road too.) No 1 exhast valve spring is also broken, and will require replacement soon too.Planing to sort out the electrics this week and engine oil/filter change, coolant replacement.Might have to build another shed before I dismantle the Dexta,for the start of its impending restoration TSG.

Hey TSG
Your'e like a man posessed with a new toy.
Never have too many sheds though eh.
Kiwi Kev

Les, I bought a modern reproduction of the Dexta tractor repair manual which includes a 41 page "special section" on the petrol engine. Dis/reassembly, specs, components, electrics. Dated Sept 1960. I could probably scan it and share it but it would take me a while... what's the best way to share such a thing? TSG I could chuck it in the mail to you if you want to use it?

Derek.

Hey Derek,

That's super!



Awesome!

I looking for info on setting the governor and carb linkage. Information from those other guys manuals may differ a bit!

Are there any more copies available from the same source?

Sharing?>>Others may have some ideas. I haven't even got around to posting photos yet!
It would be great to see a downloadable version on this site and/or Stephan's.

Thanks,
Les

Les, I'll scan it and see where we go from there. I bought the manual from a one-off online auction not a dealer so don't know its origin, there are no publication details except Ford's so it may even be a Ford re-pro.
Cheers, Derek

Derek,
I would be interested in a copy as well if you do scan it. I have an engine rebuild coming up on mine as it has started to knock.

Peter

Well it scanned ok, I can send as pdf (43 mb) or MS Publisher (31 mb) document if you let me know your email, my internet speed isn't great so we can but try! Might have to split it into two as I can only attach 25mb through my email! Alternately if I send it one of the moderators can they post it for general viewing?
Derek.

Hi Derek,

Wow, that was quick but must have kept you busy!

Sent a PM with my email address if you wouldn't mind adding it.

Just noticed that the emails from the profile page did not carry over with the updated board!

Thanks,
Les

Peter,
I sent a PM your way in Sept but it is still in my Outbox as is Derek's. Do they remain there until they are picked up or have I hit a wrong button?

A useful tip for older Petrol engines with suspect wear around the butterfly shaft etc is to squirt a very small amount of petrol onto the suspect areas and see if the fuel gets sucked in to affect the engine speed. I say older engines because the newer ones are surrounded with plastic etc, And beware that you are in close proximity to rotating parts like the fan and pulley etc.
Just my pennyworth!
Jerry
Near Bath

Hi Les,
Just looked at the PM. I note that the screen said I had no new PM's but yours was there waiting for me. I will move it to my inbox which may remove it from your outbox. Thankfully Derek has ended up with a copy.

Derek, I will send a PM with my e mail address.

Had a look at the carb on the Dexta,and sure enough the throttle shaft has excessive movement , so its just anther thing to add to the "to do list".Also the studs that hold the rear wheelbearings in on both sides were loose, 3 studs missing and 1 broken off.Who ever put the left rear wheel on also put the nuts on backwards.
Kev, hope to make a long shed ,with a long bench. After I have got the Dexta running properly ,then I plan to dismantle the tractor, starting at the front going to the rear,clutch needs to be done, and suction filter probably needs to be cleaned.Engine might only need the head taken off and sorted out.Then to reassemble from the rear to the front,then to sort out the panels and paint etc."It won't happen overnight, but it will happen!" TSG.

"kiwiland dexta", Derek, many thanks for the copy of the "Petrol Dexta Supplement"It's choice! TSG.