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Discussion Starter · #1 ·
It was all working fine when I parked it up 8 months ago ( is it really that long?! :shake:) but during trial runs to check everything over before a fresh MOT it appears to be playing up but only in D . Floor it and it will hit 4500 before slipping and dropping back to 3000 . The box has only done 6000 miles since rebuild .

Kickdown is adjusted up and fresh fluid .It'll rev out with no slipping in 1 and as fast as I can go before running out of road in 2 .Suck test tells me the new modulator is still working so . My best guess is modulator pin stuck on making it think I'm on light throttle all the time ?

Anyone else have any other ideas ?
 

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Band adjustment screw need a tweak ? can't think of anything else thats adjustable or goes wrong .
Fluid change maybe help?
 

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Governer and modulator circuits are used in D Kev. My guess is the lay up has made something stick. Both gov and mod valve when at rest should make it late shift when stuck but they could have moved on the initial drive and stuck.
Also pressure reg valve could be sticking. Some Activ8 could free them off if that is the case. Or obviously strip and check.
 

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Discussion Starter · #4 ·
Well I changed the modulator for another known good one and took it for a run...no difference.

Added some Lubegard ,automatic transmission protectant and took it for around a 5 mile run on light throttle to mix it all in ...no difference.

Blanked off the modulator ,on the basisi it shouldlmake it hang on to gears ...it didn't .

Does that help pinpoint it Andy ?
 

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Discussion Starter · #5 ·
I've stripped the back of the box off to check whether the governor was sticking and I'm told there should be a spring in there . I felt no resistance at all so stripped the circlip off the valve end and caught the shuttle valve and that was it ...no spring at all ?
The thing is this was working fine when I took it off the road so what's going on ?

I've tried searching the 'net for info re the C3 but can't find anything , a parts diagram even wouldlbe helpful. Anyone got a link stashed away somewhere ?
 

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I've stripped the back of the box off to check whether the governor was sticking and I'm told there should be a spring in there . I felt no resistance at all so stripped the circlip off the valve end and caught the shuttle valve and that was it ...no spring at all ?
The thing is this was working fine when I took it off the road so what's going on ?

I've tried searching the 'net for info re the C3 but can't find anything , a parts diagram even wouldlbe helpful. Anyone got a link stashed away somewhere ?
I'll have a look at my manual tomorrow Kev to double check there is a spring on a C3.Pretty damn sure there is,and pretty sure there isn't a circlip either.
 

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Discussion Starter · #7 ·
I'm way beyond my experience here :tdown:

The governor assembly casting bolts to the rear with 4 bolts.

One end has a weight with an inner cylinder and spring held in with circlips . The other end is a stepped shuttle ,this is where I thought there should be another spring ? There is a pin assembly that goes though the complete assembly with a circlip on the end.

I presume this spring was needed to balance the pull of the weight moving in its housing to move the shuttle over 2 hydraulic access ports.

Otherwise I can only assume that the weight operates against the pressure of the hydraulic fluid?

I can't belive it's missing though, nowhere for it to disappear to apart from down the two hydraulic ports ?
 

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Discussion Starter · #8 ·
This was posted up for me by Paul Nichols

http://www.jpat.co.uk/Ford C3.pdf

When I initially looked at it I thought I was going mad and looking at teh wrong part until I realised there are 2 different bodies and I have the early ( marked as 1974 on the governor body ) 4 bolt version .
 

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Ah ok,but there still should be a spring in there.I thought it should be the other governer pictured with the 2 bolts.
 

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Discussion Starter · #10 ·
There is a spring Andy but only in the weight end not the shuttle end ,exactly per the early governor diagram?

I remembered we spoke about pulling 2 bolts only which is when I realised what was going on.

When it's in your hands it hard to work out how it works .I couldn't see why the weight needs a spring in it and not the other end as it looks like there's nothing to prevent the weight flying out as soon as you to drive. Hence why I guessed it must be kept back by the hydraulic pressure and that pressure must compress the weight end internal spring .

Presumably as it's sprinning the weight moves outwards and must pull on the rod passing through the shuttle (when the spring compresses) allows the shuttle to move?
 

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in a nutshell yes.
I think your problem is deeper than the governer.
ANDY.
 

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Discussion Starter · #12 ·
Yup, reckon you're right :tdown: My local trans guy is on holiday for another week as well ..oh well .
 

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Kev,i had a look in my book of words this morning and if the servo/band is ok then it's certainly a valve body issue. Either the back out valve or the reg valve. Getting a pressure gauge on it and noting the pressures in all gears would be good if you could do it.
BTW,have you changed a carb/intake over the winter?
 

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Discussion Starter · #15 ·
Yes, I've changed both carb and inlet but I've a fixed vacuum gauge and thats's still reading the same ...that thought had crossed my mind as well :tup::D
 

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Yes, I've changed both carb and inlet but I've a fixed vacuum gauge and thats's still reading the same ...that thought had crossed my mind as well :tup::D
I was thinking more the kickdown linkage. It still does throttle pressure a bit too and maybe you haven't adjusted it quite right?
 

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Discussion Starter · #17 ·
Got ya ...nope, adjusted that up after / before road tests as well.
 

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Discussion Starter · #18 ·
My local auto guy removed and checkled the valve body and also checked the servo , no fault found , everything free and good :tdown:

So I've brought it back to pull the box and thought I'd just recheck a few things like kickdown linkage ( all fine ) and vacuum modulator before I pull it as it's amajor job( for me) .. I clamped the vacuum line to it shut but it's still changing gears ? I thought with no vacuum it should really hang on to gears, how come it's still shifting?
 
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