Just ordered a flex plate for a 71 140. The original ring gear is 13 mm, the one received is 8 mm. Should there be a 5 mm spacer used between the crank and flex plate. I`m wondering if the larger one is an early year one. Thank for any help. Larry

I have one of those spacers, but can't find it, try Swedish car service Coopersville mi

He shouldn't need additional spacers, but he should re-use the spacer/hub that was used with the old flexplate.

Larry, if you've lost or don't have the stock flexplate spacer/hub, let me know, I've got several used ones.
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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

The set up I have is actually a b20 from a 71 140 that had a BW35 automatic. The ring gear had some bad teeth. The flex plate ordered from a salvage yard has 8mm narrow ring gear instead of the 13mm (supposedly original to the setup) from the 140. After measuring the distance from the starter mounting face on the engine block to the front edge of the ring gear they both end up the same distance. The actual flex plate is riveted to the inside center of the ring gear on the 13mm flex plate making the extra thickness toward the torque converter. The crankshaft centering lip only has provision for the flex plate without the spacer ring which is also something I failed to notice before. I guess the narrower ring gear must help in releasing the Bendix after starting because all the later red blocks I have seen has the narrower ring gears. This setup is in my 544 with an AW71 that has worked flawlessly for 12 thousand miles. Thanks for the replies back. Larry

Hello,

It's important that you use the matching hardware for the later thinner flexplate.

The thicker flexplate had 2 pieces while the thinner flexplate has 3.

The thicker flexplate is sandwiched between the outer bolt support plate and a spacer with a protrusion for centering the flexplate that mounts on the back of the crankshaft.

The later flexplate has 3 pieces, a similar outer bolt support plate but is smaller and a spacer for the back of the crankshaft that doesn't have a centering protrusion but instead there is a separate bushing that slides into the pocket in the back of the crankshaft and it protrudes through the spacer to center the flexplate.
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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com

Thanks Eric you are exactly right.

Hello Larry,

I know that Volvo used flywheels that have ring gears with different thickness for the B18 and B20 engines, so it is possible the same applies to the flexplates.

What part number did you order and where did get it?
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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com