could it be posible that the later box used two pins in parellel to halve the curent on each connection ,
R10 Automatic Problems, and Adjustments.
- Thread starter leregulage
- Start date
Imagine this without the manual! Have we ever met, Alex?
Im going over it more in depth since that last box was a minor success. If that syncro switch is bad, it means at best the engine has to come out yet again. Not all that excited about it.
Maybe it can be cleaned in some way? The clutch sliprings looked great.
Maybe it can be cleaned in some way? The clutch sliprings looked great.
Seeing 2 volts on Wire 18 tells me Synchronisation switch has not closed and the Relay box is CORRECTLY reducing the coupling current.
I'll add the only way to know for sure is to follow the instructions for the tests I suggested in post#85
Alright, I checked the synchro switch. The test light stays lit, forward and backwards..
Not even a flicker!
Now, I wonder how hard it would be, to wire some sort of toggle, or momentary push button switch in line?
Maybe a potentiometer of sorts..
It would have to be switched, each time the car takes off under 11mph.
This thing has about 17k miles on it. I can't imagine a gently used clutch coupler would be any better..
Not even a flicker!
Now, I wonder how hard it would be, to wire some sort of toggle, or momentary push button switch in line?
Maybe a potentiometer of sorts..
It would have to be switched, each time the car takes off under 11mph.
This thing has about 17k miles on it. I can't imagine a gently used clutch coupler would be any better..
Tested as per instructions? Yellow plug disconnected?
These two observations do not correlate, if syncro switch is closed (to earth) for lamp to light then I'd expect it would show 0 volts with yellow plug connected.
With yellow plug disconnected from relay box measure the resistance of wire 18 to earth, I'd expect 0 ohms if syncro switch is closed, if it reads 2 to 5 ohms then recheck that the 10,20,18 wires are not crossed at brush carrier
Yes with the yellow relay box plug unhooked, with 12 v on one test light lead, and the other on #18.
The light stays constantly on. I then unhooked wire #18, and plugged the box connector back in.
IT WORKS! Feels like it has full power in first, and reverse. Until it goes to shift, and it just flares. Which makes sense.
I talked to a renault guy over here. He said my idea of using a momentary switch does work. Someone he knows drove one like this for years, without a issue.
Just have to click it for every action, shift, etc.. Better then nothing I guess.
Oh, and those extra pins. The middle one is not populated. The side ones are just looped with a jumper, back to the box..
The light stays constantly on. I then unhooked wire #18, and plugged the box connector back in.
IT WORKS! Feels like it has full power in first, and reverse. Until it goes to shift, and it just flares. Which makes sense.
I talked to a renault guy over here. He said my idea of using a momentary switch does work. Someone he knows drove one like this for years, without a issue.
Just have to click it for every action, shift, etc.. Better then nothing I guess.
Oh, and those extra pins. The middle one is not populated. The side ones are just looped with a jumper, back to the box..
full power in 1st and reverse makes sense, the flaring suggests the synchro switch has opened.
It's worth testing the resistance of wire 18 to earth, if wires on brush carrier were crossed the test lamp would be always on......
Whilst the yellow coupling plug is removed what is the voltage on the relay box pin 18?
This is the voltage I'd expect you'd measure when syncro switch is open, and gets pulled down to 0v when it's closed.
It's great to hear that the clutch works properly some of the time. I think there is good reason to be optimistic for a completely operable automatic here!
When the synchronization switch failed in my Dauphine, the clutch engaged fully, but did not disengage fast enough on downshifts. I guess the switch could fail open or the contacts could short. Your problem is different from mine. My guess is that it may be possible to remove or partially remove the slip ring assembly to fix the synchronization switch. Someone put it together, so it can probably be taken apart (very carefully). This does mean taking the engine out again - which I would not do until you are certain that is the problem.
Keep up the good work, you will get it going properly! When working, it feels just like someone driving a manual gearbox. It works well without any obvious quirks.
When the synchronization switch failed in my Dauphine, the clutch engaged fully, but did not disengage fast enough on downshifts. I guess the switch could fail open or the contacts could short. Your problem is different from mine. My guess is that it may be possible to remove or partially remove the slip ring assembly to fix the synchronization switch. Someone put it together, so it can probably be taken apart (very carefully). This does mean taking the engine out again - which I would not do until you are certain that is the problem.
Keep up the good work, you will get it going properly! When working, it feels just like someone driving a manual gearbox. It works well without any obvious quirks.
I'm hopeful it's drivable soon. The brake master cylinder has gone bad. Was rebuilt recently, but it's just no good. So that will delay road tests for a bit.
As for that pesky wire #18
With plug off box, to ground. 1.5k ohm
Plug still unhooked for next tests!
With car running at idle. .6 volt
With car in gear, and govner switch energized. 2 volt. Didn't try reving it in gear...
As for that pesky wire #18
With plug off box, to ground. 1.5k ohm
Plug still unhooked for next tests!
With car running at idle. .6 volt
With car in gear, and govner switch energized. 2 volt. Didn't try reving it in gear...
A premise of troubleshooting any control system (ancient or modern) is to validate the inputs as 'Garbage In' equals 'Garbage Out', so not having any brakes is a good prompt to do the wheels in air tests I've suggested.
Why bother you ask, well I believe Wire 18 is connected to Blue Governor plug wire 8 which is the open throttle input.
The blue wires in the blue circle are the combination of the sync and accel switches which switch that diode in and out of the 'transistor' circuit they talk about.
The white circle is the Coupling current wire 20.
The yellow circle is the 11/6 input to the coupling transistor circuit.
Sorry, yellow circle is in wrong spot, it should be 1" lower to the left
Have fun
Why bother you ask, well I believe Wire 18 is connected to Blue Governor plug wire 8 which is the open throttle input.
The blue wires in the blue circle are the combination of the sync and accel switches which switch that diode in and out of the 'transistor' circuit they talk about.
The white circle is the Coupling current wire 20.
The yellow circle is the 11/6 input to the coupling transistor circuit.
Sorry, yellow circle is in wrong spot, it should be 1" lower to the left
Have fun
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mmm, from the description I'd expect the sync switch to be two contacts with zero resistance so the 1.5k must be a poor earth somewhere.
Its very possible. If there is anything I can do, other then taking half the car apart, I'm all for it. I'll try some jack stand testing.
I kind of look at it a bit each day. Im trying to fix something here and there.
It has good grounds all around the engine, and gearbox. All check out just fine, with no notable resistance. The car is just screwy!
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Is there a gasket between gearbox and actuator? Maybe try adding one from chassis rail to actuator housing, though I admit I can't see how the coupling earths through the input shaft, be more likely to be via the brush carrier which makes me wonder if wire 10 doubles as an earth???
I have no idea, its certainly oily enough to need one.
That's a good idea, the extra earth I mean. Eliminates a possible variable. I once solved a frustrating running problem with a separate earth to my distributor body - you wouldn't think the distributor wasn't earthed adequately, but it wasn't.
Or could be poor contact resistance between the brush carrier, brushes and slip ring on the coupling.
Does the resistance between wire 10 and 20 measure 3 to 5 ohms on disconnected yellow plug?