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Discussion Starter · #41 ·
then see post no.31.. you wont over entend the travel.. you will feel the release and shift.. ever notice that shifting into 1 st and reverse you need more ' clutch ; then shifting into the other gears?...just make the new rod.. as in post no.31, 6 mm longer than the one you have
Sounds like a plan for tomorrow morning! Fingers crossed that it works
 

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Richard Jemison
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There`s only a few things that can be done to get correct petal "release" position, which is no more than 1/2 way to the floor. (Racers prefer it releasing close to the top).But with such yoy need a petal stop to prevent over extending the spring plate in the pressure plate.
You can unscrew th push rod on the master cyl a few turns to increase effectiveness of the petal movement, but only to the point where the pressure from the slave can be returned to the reservoir when released.
The other is to lengthen the push rod as I`ve stated in many post. 5/16" seems to be the minimum to get needed throw length.

You can not use a steel rod "rounding the ends as it will only go through the hole in the release arm. I`ve used a lon 3/8 bolt removing the head and rounding that end them using a rounded nut as the contact point on the release arm to make an adjustable length rod. Just use a 2nd nut as a "lock nut" to maintain it`s position when the rod is adjusted to position the piston within 1/8" of it`s max rearward travel.
 

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Not sure where you are but I probably have an old slave cylinder rod sitting around somewhere if needed
 

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Not sure where you are but I probably have an old slave cylinder rod sitting around somewhere if needed
There was mention above that the "new" cylinders might have a shorter shaft.
Greg: Can you measure your shaft and post??
 

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As to my suggestion above about switching to a steel jacketed hose. The Slave cylinder can only "push" a fixed amount of brake fluid. If some of that "pushed" fluid goes into expanding the hose and not moving the slave piston, the slave piston will not move as far. Thus shorter throw/movement on the clutch arm,...
 

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There was mention above that the "new" cylinders might have a shorter shaft.
Greg: Can you measure your shaft and post??
Well, it is thunder and lightning and rain out there but for you guys, I braved the elements. :LOL:
 

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Discussion Starter · #47 ·
Well, it is thunder and lightning and rain out there but for you guys, I braved the elements. :LOL:
Now that's interesting, I measured the one on my new clutch slave at 2.83 inches...
 

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Discussion Starter · #48 ·
Anyhow, I went forward with the clutch slave rod modification. I'll post some pictures below but the clutch now engages about half way through the pedal travel and bites firmly which is great, however, second still grinds :mad:. The clutch used to engage almost with your foot completely off the pedal so this is a big improvement,despite the second gear still grinding.

Now, the pedal does feel softer than it did and I would've thought the opposite. Maybe now the the rod is longer I need to readjust the travel at the master cylinder?

I'm going to try changing the transmission fluid tomorrow to see if it helps but I can't imagine why it would still grind into second and not any of the other gears unless the new synchro I put in is defective.
 

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Discussion Starter · #49 ·
Here's how I lengthened the rod for those interested:

I started by cutting up a 3/8ths bolt (I over sized the length and used the shoulder of it so that there would be no threads) and then carefully welded it to the end of the clutch slave rod. The bolt I used was a grade 8 bolt but it doesn't real matter as you'll temper the part when you weld it so it will be machinable. I had it in a vise with a groove cut into it perpendicularly to hold it center. This was very important as if the weld came out angled it'd be impossible to true the part.

1685266

Here's the welded push rod, all the welds were done through the notch in the vice to keep everything lined up.

Next, I took it to the lathe to clean up and cut it to 80mm (about 8mm longer than it was) in length and made the diameter a consistant 8.75 mm throughout. This took off less than a thousandth of an inch on the existing rod and trued the new extension Then the end was tapered to how it was on the original part.
1685269
1685270

Here's the new part ready to install. To get it in I did have to remove the front rearward cir clip on the clutch slave and slide the slave forward a bit. It was quite successful in pushing the engagement distance more inwards towards the floor on the pedal travel.
 

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Make sure that the pedal has some slop in the fully upright position so that the slave is completely unloaded when pedal is upright. In other words, the fork should not have any pressure on it until the clutch pedal is depressed. Adjust the slack to be minimal, but a tiny bit there, with the adjustment rod up top.
 

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Discussion Starter · #52 ·
As to my suggestion above about switching to a steel jacketed hose. The Slave cylinder can only "push" a fixed amount of brake fluid. If some of that "pushed" fluid goes into expanding the hose and not moving the slave piston, the slave piston will not move as far. Thus shorter throw/movement on the clutch arm,...
The line in there is a stainless steel hose
 

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Discussion Starter · #53 ·
Make sure that the pedal has some slop in the fully upright position so that the slave is completely unloaded when pedal is upright. In other words, the fork should not have any pressure on it until the clutch pedal is depressed. Adjust the slack to be minimal, but a tiny bit there, with the adjustment rod up top.
There is a little bit of slack, should I be able to push the rod in at all with everything installed or should it be as far in as it goes? I can push the rod into the clutch slave about a 1/4 inch before it stops moving, it does sit naturally on the clutch form tho.
 

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no, the slave piston does not need to be at the end stop. You do want to make sure that you can manually, with your hand, move the fork back and forth a tiny bit, which says that the slave is unloaded when the pedal is fully up. You dont want the fork to have any preload on it.
 
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it's almost a alfa romeo spider
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Here's how I lengthened the rod for those interested:

I started by cutting up a 3/8ths bolt (I over sized the length and used the shoulder of it so that there would be no threads) and then carefully welded it to the end of the clutch slave rod. The bolt I used was a grade 8 bolt but it doesn't real matter as you'll temper the part when you weld it so it will be machinable. I had it in a vise with a groove cut into it perpendicularly to hold it center. This was very important as if the weld came out angled it'd be impossible to true the part.

View attachment 1685266
Here's the welded push rod, all the welds were done through the notch in the vice to keep everything lined up.

Next, I took it to the lathe to clean up and cut it to 80mm (about 8mm longer than it was) in length and made the diameter a consistant 8.75 mm throughout. This took off less than a thousandth of an inch on the existing rod and trued the new extension Then the end was tapered to how it was on the original part.
View attachment 1685269 View attachment 1685270
Here's the new part ready to install. To get it in I did have to remove the front rearward cir clip on the clutch slave and slide the slave forward a bit. It was quite successful in pushing the engagement distance more inwards towards the floor on the pedal travel.
:oops:if you paint it RED , it will give you at least 20 extra 'butt ' hp
 

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it's almost a alfa romeo spider
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There is a little bit of slack, should I be able to push the rod in at all with everything installed or should it be as far in as it goes? I can push the rod into the clutch slave about a 1/4 inch before it stops moving, it does sit naturally on the clutch form tho.
you are ok, at this point
 

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it's almost a alfa romeo spider
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Anyhow, I went forward with the clutch slave rod modification. I'll post some pictures below but the clutch now engages about half way through the pedal travel and bites firmly which is great, however, second still grinds :mad:. The clutch used to engage almost with your foot completely off the pedal so this is a big improvement,despite the second gear still grinding.

Now, the pedal does feel softer than it did and I would've thought the opposite. Maybe now the the rod is longer I need to readjust the travel at the master cylinder?

I'm going to try changing the transmission fluid tomorrow to see if it helps but I can't imagine why it would still grind into second and not any of the other gears unless the new synchro I put in is defective.
the 2nd gear in these trannys are not the best.( remember its a german tranny,, and they might still have some hurt feeling after the last war lol ).. before you put new oil in the tranny, flush it out with paint thinner... stuff the rear of the car in the air.. stuff it in 3 or 4th gear.. rotate the rear wheels so the drive shaft will rotate.. do a lot of rotations. let sit overnight..drain all the thinner out...then refill with correct oil
 

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Anyhow, I went forward with the clutch slave rod modification. I'll post some pictures below but the clutch now engages about half way through the pedal travel and bites firmly which is great, however, second still grinds :mad:. The clutch used to engage almost with your foot completely off the pedal so this is a big improvement,despite the second gear still grinding.

Now, the pedal does feel softer than it did and I would've thought the opposite. Maybe now the the rod is longer I need to readjust the travel at the master cylinder?

I'm going to try changing the transmission fluid tomorrow to see if it helps but I can't imagine why it would still grind into second and not any of the other gears unless the new synchro I put in is defective.
Well, that shoots theory about new ones having shorter shafts.
If you go ahead with the gear oil change, make sure you can remove the fill plug before you open the drain plug.
 
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But Mad North-Northwest
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Well, that shoots theory about new ones having shorter shafts.
Yeah, that didn't seem right to me. A lot of folks (including me) have installed slave cylinders over the past few years, and this is the first I've heard of that being an issue.

Anyhow, I went forward with the clutch slave rod modification. I'll post some pictures below but the clutch now engages about half way through the pedal travel and bites firmly which is great, however, second still grinds :mad:. The clutch used to engage almost with your foot completely off the pedal so this is a big improvement,despite the second gear still grinding.
Something doesn't make sense here. If the clutch was engaging with your foot almost all the way up before the mod, then it seems like you had plenty of throw and were getting plenty of clutch disengagement when you pushed the pedal. Extending the rod should've increased the throw such that the engagement point would move UP, not down, right?

Am I misunderstanding something here? If the clutch was releasing near the top, there's no way you should've gotten gear grinding with the clutch all the way down. That suggests you had plenty of clutch throw and no slave problem.

Reverse will always grind from neutral on a Spider unless you wait a few seconds to shift after pushing the pedal down. Second will typically grind if you shift too fast, or on downshifts. I'm not sure you had a clutch disengagement problem to start with: can you clarify how you determined that?
 
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