s2 limited slip differential no preload?

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Th0m4s
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s2 limited slip differential no preload?

Post by Th0m4s » Sat Apr 21, 2018 1:35 pm

I just inspected my clutch type 24 spline differential yesterday and found something strange. There are no springs at all inside it to press down the clutch packs when I'm not braking or accelerating. Did Mazda really build the early RX7 diffs without those springs or am I missing a part? Shouldn't there normally be some conical springs pressing on the clutch disks?
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TOOL
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Re: s2 limited slip differential no preload?

Post by TOOL » Sun Apr 22, 2018 6:41 am

There’s very slight conical springs on each end of the clutch packs.

Normal.

Chances are your thrust washers need replacing though.
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Th0m4s
Posts: 45
Joined: Sat Oct 31, 2015 1:40 pm
Location: Stuttgart/Germany

Re: s2 limited slip differential no preload?

Post by Th0m4s » Sun Apr 22, 2018 10:45 am

There are no conical springs inside my differential. I've found out that mine is a very early version and mazda really didn't use springs in them. It also has only flat friction disks without any oil groves in them.
Now I've got an other problem: I can't find anything about that differential in the fsm and I can't find any part numbers for the friction disks. That diff seems to be extremely rare.
Rotary Engines: Behold the power of two doritos on a stick!

TOOL
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Re: s2 limited slip differential no preload?

Post by TOOL » Sun Apr 22, 2018 6:00 pm

Pics or it didn’t happen
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Th0m4s
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Re: s2 limited slip differential no preload?

Post by Th0m4s » Sun Apr 22, 2018 10:11 pm

Image
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TOOL
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Re: s2 limited slip differential no preload?

Post by TOOL » Mon Apr 23, 2018 8:20 pm

How many clutch plates either side?

Hard to tell but looks like you have 3 inner tabs and 2 outer tabs.

You should only have 2 of each.

Someone’s been in there before and taken out the comical springs.

They should sit over your thrust washers.
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Th0m4s
Posts: 45
Joined: Sat Oct 31, 2015 1:40 pm
Location: Stuttgart/Germany

Re: s2 limited slip differential no preload?

Post by Th0m4s » Tue Apr 24, 2018 7:12 am

There are 4 plates at each side. I found out the differential is an early type from somewhere between 1970 and 1978 meant for racing. It was never sold in street cars by Mazda and it never had conical springs.
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TOOL
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Re: s2 limited slip differential no preload?

Post by TOOL » Tue Apr 24, 2018 1:48 pm

Show me the ramp angles
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Th0m4s
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Re: s2 limited slip differential no preload?

Post by Th0m4s » Tue Apr 24, 2018 9:00 pm

Image
Image
Image

Interesting, isn't it? :mrgreen:
Rotary Engines: Behold the power of two doritos on a stick!

TOOL
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Re: s2 limited slip differential no preload?

Post by TOOL » Thu Apr 26, 2018 8:05 am

Yeah, that’s pretty different.

I’ve seen those ramp angles once before. I didn’t realise how different the internals were though.

Separate pieces for the spider gears too.

How thick are those clutch plates?
Back in sunny France

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