1998 v70 clutch master cylinder problems

ghansenv70 · Post by **ghansenv70** » 17 Oct 2023, 17:54

So I was driving. And as I goto shift I press in the clutch and hear lost of plastic snapping and the clutch pedal deceided to stay on the floor. Turns out the arm coming off the master cylinder that connects the master cylinder to the clutch pedal had snapped in half. So I ordered the new one and went to install it but when I opened the box it didn’t come with the hardware that connects the arm to the clutch pedal. I have been unsuccessful in finding what this pin or bolt is. Any help is appreciated

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Post by **scot850** » 17 Oct 2023, 19:09

Can you see it on this if you use the magnify option on the drawing?

https://www.volvocarstorontoparts.ca/a/ ... 73525.html

Neil.

Post by **foggydogg** » 17 Oct 2023, 23:16

ghansenv70 wrote: ↑17 Oct 2023, 17:54 So I was driving. And as I goto shift I press in the clutch and hear lost of plastic snapping and the clutch pedal deceided to stay on the floor. Turns out the arm coming off the master cylinder that connects the master cylinder to the clutch pedal had snapped in half. So I ordered the new one and went to install it but when I opened the box it didn’t come with the hardware that connects the arm to the clutch pedal. I have been unsuccessful in finding what this pin or bolt is. Any help is appreciatedimage.jpg

It looks like the pin has detached* itself from the pedal, you may need 9191520

: 9191520.JPG (340.58 KiB) Viewed 385 times

The pedal shaft itself isn't solid, it's formed sheet stock seam welded, and the pins are both pressed into holes and end welded on the off side.
viewtopic.php?p=615973&hilit=9191520#p615973
Once you get the whole mess off the shaft, find somebody with tig welding skills, sometimes exhaust shops can be a resource.
.*Fatigue shear, what I should have said is it broke off. See the thread referenced, new pedal seems NLA .

Post by **abscate** » 18 Oct 2023, 04:17

That clip will slide off , then the pin drops out. Why can’t you reuse the old hardware?

Post by **foggydogg** » 18 Oct 2023, 07:07

That pin is likely a partial remnant of the clutch pedal assembly. I owned its twin for a time. Fabrication or a dip into the Volvo parts bin* are next.
[attachment=0]IMG_0247.JPG[/attachment

The probable failure mode was pin break, plastic break, walk.
*(Edit:
Oops. Even Skandix says NLA.)

ghansenv70 · Post by **ghansenv70** » 18 Oct 2023, 21:35

Thank you all for your help. I was digging around in the spare parts I got from when I bought the car and I got luck and found a spare clutch petal with the pin intact.

ghansenv70 · Post by **ghansenv70** » 18 Oct 2023, 21:37

My only worry now is what could of cause the stud to sheer off the clutch pedal as it would require some force. I’m hoping that the master cylinder locked up but I am starting to worry about the slave cylinder or the clutch itself

Post by **Clemens** » 19 Oct 2023, 02:14

I think it was just wear by age or a weird coincidence. Some people run surprisingly stiff race clutches in these Volvos and don't break the stud off the pedal.
You should not be able to shear off that stud, this should hold way more pressure than humans can possibly create.

Post by **foggydogg** » 20 Oct 2023, 11:06

ghansenv70 wrote: ↑18 Oct 2023, 21:37 My only worry now is what could of cause the stud to sheer off the clutch pedal as it would require some force. I’m hoping that the master cylinder locked up but I am starting to worry about the slave cylinder or the clutch itself

25 years and thousands of shift cycles can fatigue any metal bits. Since it is only welded on the 'far' end of the pin, any slop in the fit on the spring side of the pedal can cause it to flex inside the hollow shaft. My guess is the problem has happened plenty of times, it just hasn't gotten much airtime. Situation status is now critical since the part is NLA. Congratulations on finding a spare. Think about fixing the old one if you can.

ghansenv70 · Post by **ghansenv70** » 01 Mar 2024, 13:06

Update some good news some bad news. The new clutch master is in and connected and the booster is back in place and the engine bay is for the most part back together. The bad news is the pedal box. Eveything is bolted in and tight and hooked together but the brake pedal has at most 2 inches of play in all directions and feels very lose. The cute pedal has play but is not nearly as bad and both pedals at not contacting there coresponding switches. I’m stumped. I know that the bolt that runs through both pedals as little plastic bushing inserts that I believe were installed and my friend said he was able to barely see installed but I personally can’t see them. And I wonder if the pedal box needs to be adjusted to contact the clutch position switch and brake switch. I don’t know next steps for either of these issues and was wondering if anyone had tips for reinstalling the pedal box or has had similar issues