Automatic counterweight removal tool that comes with every N/A RX-7
04-01-17, 06:19 PM
#1
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Automatic counterweight removal tool that comes with every N/A RX-7
For years I have removed flywheels the old-fashioned way: a few solid hits on the clutch surface with the largest soft-faced deadblow hammer I could lay my hands on.
This won't work if you are pulling an automatic engine apart!
I have only pulled apart one other automatic engine, and I made a puller tool for that one. I had to get more inventive this time. What I did was this:
What you see is the upper clamshell from a broken N/A transmission mount. Drill the holes out so a 10mm bolt can pass through (a Unibit/step drill is a lot easier than a regular drill bit, for this). Thread the 54mm nut on so it is only halfway on. Use the two short transmission-to-engine bolts to bolt this to the counterweight. One of them should have a huge captivated washer, put that one on the slotted side for good measure. Then, after tightening it down until the mount starts to warp, give the center a few solid thwacks with an iron hammer.
This won't work if you are pulling an automatic engine apart!
I have only pulled apart one other automatic engine, and I made a puller tool for that one. I had to get more inventive this time. What I did was this:
What you see is the upper clamshell from a broken N/A transmission mount. Drill the holes out so a 10mm bolt can pass through (a Unibit/step drill is a lot easier than a regular drill bit, for this). Thread the 54mm nut on so it is only halfway on. Use the two short transmission-to-engine bolts to bolt this to the counterweight. One of them should have a huge captivated washer, put that one on the slotted side for good measure. Then, after tightening it down until the mount starts to warp, give the center a few solid thwacks with an iron hammer.
04-02-17, 06:38 AM
#3
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Thread Starter
I was thinking that, but it looked to me like the bolt was just glancing off of the seal surface and I didn't want to get myself into a Three Stooges situation with a mangled rear stationary gear and a bent-over bolt that was stuck in the counterweight.
04-04-17, 08:52 PM
#6
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i have a CW with a mangled bolt in it. its not bad, i think its just mushroomed a little
04-04-17, 10:57 PM
#7
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The funny thing is all of the core engines I got were junk, the automatic had severe chrome flaking, worn apex slots, flattened springs, one broken apex seal corner, etc. but the side housings had minimal wear. The original engine to the car had severely worn side housings and all side seals/oil seals were scrap, flattened apex seal springs, but the rotor housings were almost perfect and the rotor slots are measuring out at less than 3mm which actually doesn't make sense to me. So of the three series 3 12As I got, none had any usable parts (one even had a bad eccentric shaft, how does that even happen?), but of the two series 2 12As I have, I can use the rotors and rotor housings from one, and the side housings and all the seals from the sides of the rotor from the other.
Well, i haven't measured side seal heights yet, but I have a feeling they will be good. The ones from the S2 that ate the side housings had side seal heights that varied over .010" from the leading edge to the center.
Last edited by peejay; 04-04-17 at 11:01 PM.
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04-05-17, 09:54 AM
#8
worn 12a rotor housings? you're kidding right? 
sad part is even good ones people don't want to pay for, scoffing at figures of $150+. i'll keep em til they realize the value in finding actual good ones.
sad part is even good ones people don't want to pay for, scoffing at figures of $150+. i'll keep em til they realize the value in finding actual good ones.
Last edited by RotaryEvolution; 04-05-17 at 10:06 AM.
04-05-17, 11:59 AM
#10
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There's a pair of NOS 71-73 rotor housings on there for only $1000!
04-05-17, 12:04 PM
#11
i sold a pair of 1971 12A housings for $100 that i reconditioned and looked new, was kinda lucky to even get that. didn't even get a feedback rating on the sale...
Last edited by RotaryEvolution; 04-05-17 at 12:08 PM.
04-05-17, 12:34 PM
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ive got a bunch of the 71-73 engine parts, even some NOS plates. i may even build one!
04-12-17, 12:38 AM
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I made a bar out of flat steel (1/2 inch thick)about 30 inches long and drilled some holes in it at the proper spacing to take out regular Flywheels.They have the 2 bolt holes in them on the inner surface near the Eccentric shaft nut.
You put 2 bolts with "extra nuts" into the holes and then you can tighten them and it will pull the flywheel up and off the Shaft.
Banzai's apparatus is pretty well like what I am talking about.Only mine is a bar..and instead of where the washers are you have some nuts on the surface so the length of the bolt won't bottom out.
You put 2 bolts with "extra nuts" into the holes and then you can tighten them and it will pull the flywheel up and off the Shaft.
Banzai's apparatus is pretty well like what I am talking about.Only mine is a bar..and instead of where the washers are you have some nuts on the surface so the length of the bolt won't bottom out.
