Folks,

Recently had the B20 rebuilt in my '68 145 and I working on getting it installed and setup. I went to adjust the clutch and found the clutch fork was hitting the bellhousing before the clutch was fully disengaged. This engine is running a resurfaced 8-bolt flywheel from a B20, a Sachs clutch kit with Sachs throw-out bearing, a new clutch fork, and a M41 transmission. I had a second flywheel lying around that was about ~0.100" thicker and this improved the situation but the clutch fork still hit the bellhousing before the clutch fully disengaged. I have replaced a clutch several times on 140s and early 240s without this issue, so I am a bit stumped as to what is causing this problem.

I also randomly had a different style throw-out bearing in my garage from an old engine, which IPD labels as a "Borg and Beck" throw-out bearing . This bearing is taller but still interacts with the same point on the clutch fingers as the Sachs throw-out bearing. With this bearing installed instead of the Sachs bearing, the clutch fork sits much father back in the "window" and easily disengages before hitting the bell housing.

Has anyone else had this issue before? Any other ideas what might be causing the problem with my clutch and flywheel installation requiring me to use this taller bearing? I am hesitant to run this new bearing as obviously it didn't come with the Sachs kit.

Sachs clutch kit w/ throw-out bearing: https://www.ipdusa.com/products/5649/Clutch-Kit-Sachs-KF24201-Volvo-271263?crumbs=0,969,1341
Borg and Beck throw-out bearing: https://www.ipdusa.com/products/16556/Release-Bearing-Borg-and-Beck-Genuine-Volvo-672122?crumbs=0,969,1341

Thanks in advance!
Brian

Hi,

You said you put in a new clutch fork so I wondered if you need to adjust the pivot ball height?

On some clutches it is between you and the input shaft or on the other side, like on the 240s it holds the opposite end.
The ball is a fulcrum point of a lever on the one style but a it’s lifting point on the other far end to get aligned across the fingers.
I have no idea which transmission you have that far back but either design works.
The remake of throw out bearings could also be the cause no doubt.
The ball stud was an additional adjustment needed for variations in manufacturing or tolerances.

With the one on your side it is adjusted to far out towards the engine and loses throw.
With the one like on the 240s it is not out far enough so it sets the fork too far backwards as technically it doesn’t pivot but gets pulled into the clutch fingers.

I believe they are both screwed into the housing from the inside but locked in place from the outside.
You are supposed to do the adjustment before installing the transmission onto the engine.
It gets adjusted to something of slightly more in stroke of what it takes to press the fingers in to disengage the clutch disc.

You might be able to remove the outside nut and try to turn the whole ball’s stud while in place. There is a hex for doing that on the inside but doubtful to do it from the opening and on 240s it cannot be seen.

Without pressure on the fork it should be able to move fairly easily but if not, you may have to double nut the thread sticking out to be able to give it a turn or two.

A couple of threads will produce quite a bit of throw in one direction or another.
It’s about centering the length of stroke.

Other than what I have said I have no other clues as you are seeing that it’s hitting the housing and you are not running out of pedal stroke from above by cable or hydraulics.

Post back what you get to work as it helps others.

Phil

Phil,

Excellent info, thank you! I will take a look this weekend and report back

Brian

I was going to suggest what machine man wrote about-- the height of the pivot ball. BUT ALSO--early in the 140 production there was a problem with clutch forks bending. Maybe your problem lies in that area. - Dave

Sounds great!

I just hope the Brickboard is up and running as it has been not responding for quite a few times a week lately.

Phil

As unlikely as it may be I think it may be a simple matter of having the wrong release bearing in the kit. Is the old one available to compare? It's been at least 20 years since the last time I had my M41 out ('69 144). - Dave

I do have the old Sachs throw-out bearing and they look nearly identical in height and design.

Unfortunately the new reproduction clutch release forks aren't made correctly, something we found out a couple of years ago and this includes what Volvo is now selling.

At the time, we still had new old stock clutch forks, so we installed those.

The problem lies in the location of the 2 pins that hold the release bearing.

As suggested, installing some shims under the pivot might make the new clutch fork work.
--
Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

Eric,

We measured the new clutch fork vs. an old one on I have on hand but couldn't find any (major) deltas. Do you have any more details on what exactly was different? I will break out the calipers and take a more concerted look at the two.

Brian

What we noticed was the 2 pins that hold the bearing weren't in the same place.

There maybe other anomalies, but we didn't investigate further as we had NOS and good used release forks at the time.

What we knew for sure was that the repros weren't working.

By this time, it was just another in a growing list of repro parts that weren't made correctly and since we were being ignored by our suppliers when we complained even when we took the time to determine the details of the flaws in the parts we didn't investigate further.
--
Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com