Root79Rx7

Today i took a blown 12a out of my car and put a new one into it, with the blown one i got bored and since i have never seen the inside i started taking it apart i had a great time looking inside of her untill i got to the 2 1/8 inch nut on the flywheel(how hard is it to get off), well next week i am going to Slay this Dragon and get its heart, im going to try to get the rotors out, im not much of a machanic but i cant wait to see the housing and rotors, so much fun working on this car. I dont see how i could every port the motor and put it together and make it run again.

MakeRX7UpYours

There is a special tool needed to remove the flywheel nut... It's some sort of torque multiplier, and it's impossible to remove without it, in my experience.

Root79Rx7

I think we are just going to cut it off with a die grinder* spelling? hehe i like to see that

MakeRX7UpYours

Knock yourself out, champ.

QuagmireMan

light that nut up, then pass it to the left

peejay

Special tools for removing flywheel:

6' long 1" angle iron
Floor jack handle
Socket
Appropriate sized breaker bar (most likely 3/4", whatever fits the socket)
BIG soft faced hammer/mallet

Drill two holes in the angle iron on one end to coincide with two of the pressure plate bolt holes. Bolt the angle iron to the flywheel and stand on it. Put the socket on, attach the breaker bar, slide the floor jack handle on over the breaker bar, pull up to loosen, Nut should pop free. Back off nut two turns. Smack the flywheel around the edges (on the pressure plate registers) until it pops free.

Good idea to loosen the front pulley bolt (3/4" / 19mm) AFTER you break the flywheel nut free and BEFORE you remove the flywheel. You'll need some hefty stop-bar action to counteract the large amount of torque required to pop the front pulley bolt loose, and that much torque applied to the (untightened) flywheel will help break it free of its taper fit.

After that, disassembly is a pile of cake.

Slammed_GSL

iTrader: (14)

54mm(2 1/4in) socket and a air impact wrench....fly's right off in 2 seconds. I broke a breaker bar trying to do it by hand, that puppy is on there tight!!!!

Root79Rx7

thanks guys

Pele

iTrader: (28)

I thought you're NEVER supposed to touch the front pulley bolt... Something about needle bearings or something.

mcnannay

yeah for sure, get your hands on an air impact wrench, makes life so much easier...

my biggest problem was getting the flywheel off after that, i stripped my puller bolt trying to do that, what a pain in the ***

by the way...just finished my rebuilt today!!! im so happy!!!

Jeff20B

iTrader: (13)

2 1/4" is too large. Get a 2 1/8"

Bolox

yeah careful when you take off the fly wheell...

and for gods sake.. if you decide to heat it off.. make surre you take out all the plaugs (spark/oil).. else that puppy'll blow (learnt this the hard way )

-Cheers

Slammed_GSL

iTrader: (14)

2 1/8!! I knew something didnt' sound right when I typed that!
Thanks for the correction 20B!

Rutnick

yeah, while the engine is ASSEMBLED! He's taking it apart. You can take the front pulley off while it is installed IF you wedge a piece of wood on the clutch pedal to keep it engaged.

ArChAnGeL120

its a 2 1/8 inch (54 mm i believe) nut tightened to 289 to 362 ft/lbs (400-500 n/m) so it's on there pretty damn good, without a flywheel brake you aren't going to get anywhere with it. and unless your a diesel mechanic, try a 1/2 in drive air impact wrench (diesel mechanics may have a breaker bar ) otherwise beseides those 2 your kinda in a tough spot... take that bitch out.

Jeff20B

iTrader: (13)

No problem. I know a guy who got a 2 1/16" wrench from Snap On (BFW!) and it was too small. Then he got a 54mm chrome 12 point socket that wasn't that great. All the while, the black (correct for impact use) 2 1/8" 6 point 3/4" drive socket was just sitting there. I got one and a 3/4" to 1/2" drive reducer for my 1/2" impact wrench and it has worked perfectly on several engines so far. I learned from his mistakes.

Oh, I also got one of those flywheel brakes from Mazdatrix. It makes life so much easier for clutch bolt torqueing, 19mm bolt torqueing etc.

1stgen_tn

I got my 2-1/8" at a Tractor parts store. Has a 1" drive I think so I had to get an adapter to fit my 3/4" breaker bar. I used just a 3ft long lead water pipe, bolted the flywheel down to a 8ft long angle iron and jumped on the pipe. Dangerous? Well maybe, but it broke lose first on the first hop. I only weigh 160lbs. and I think Sport Compact Car magazine mentioned in a article way back that it takes 300-350lbs. torque.

1stgen_tn

err. maybe my socket is 3/4" and my breaker is 1/2", it's one or the other anyway......

bliffle

Impact wrench is good idea: the stutter is better than constant torque of a breaker bar. I don't have a compressor (and I don't want to buy one and store it and lug it around) so I have a Dewalt DW052 Impact Driver (for driving deck screws - and it'll run a Simpson 1/4 x 3" screw into a fence post without a pilot hole) that puts out 100 ft-lb max torque (which I believe is about what compressor impact wrenches put out) and loosens most frozen nuts/bolts. It's pretty light and compact and uses a dewalt 12v. battery so it's good for salvageing stuff at the junkyard. I paid $100 on eBay.

I also have a DW059 1/2 drive cordless impact wrench, which is an 18v. beast that puts out 300 ft-lb. That monster will about twist your arm off! I'd be willing to haul it around to anyone in the SF bayarea and try removing that flywheel nut! Haven't o'hauled a rotary yet myself. I bought it for $290 on eBay with 2 batteries and charger (which made the cost for the wrench about $100 net).

They have that 2 1/8 socket at Sears for $22. That same damn size occured last year in a plumbing project of mine, so I bought it, used it, and returned it undamaged. Claimed it was slightly wrong size and I really needed a metric size. So I bought some other stuff with the $22.

B

peejay

But we're disassembling the engine...

If you just CRACK the pulley bolt loose but don't loosen it more than maybe 1/4 turn to be safe, you're not going to risk dropping the thrust bearings.

What I do, since paranoia is a Way of Life when wrenching, is crack it loose (break the rust/tension bond), then snug it down wrist-tight with a ratchet. That way it's still tight enough to beat on the flywheel, but it will still come loose easily without trying to figure a way of keeping the shaft from rotating.

Pele

iTrader: (28)

See, I wanna rebuild my 12A... It runs fine now, but needs ported... Besides it's got 180K on it and been overheated once or twice since I've had it. (Radiator popped. Didn't leave it on hot for more than a few minutes. Hot = 3/4 gauge)

I planned on dismantling it, taking the side plates and rotor housings somewhere to be measured and have the side plates lapped and the porting done... (I have no micrometer.)

But at 180K miles, people say that the chromium coating is probably peeling off the rotor housings. That and you shouldn't lap the side plates cause you remove nitride coating and that shortens their useful life. Then I've seen pics of the wear on the apex seal grooves on the rotor... And I dunno the life span of rotor bearings or main bearings.. All this makes me think I need all new ****.

On top of that, the pics of the destroyed thrust needle bearing on Mazdatrix makes me thing I might not be cut out for this...

I dunno if I can bring in a pile of parts as a core, so I'm reconsidering building it up myself as opposed to just taking it somewhere and having them rebuild it.

Then again, there's the whole $$$ issue. Plus everybody here says it's not that hard...

If there was some way that I could know that wither I won't need new parts aside from seals and springs, or I could be reasonably sure that I won't trash it when I first start it up, I'll do it.

But I can't x-ray the engine and I don't have the experience that'd give me the foresight into the job... Therefore it's all unknown...

Unless of course someone will tell me a place that'll take a pile of parts as a core.

"Look man, I tore it down FOR you... I should get extra cash back on my core charge!"

SERIES 1 XLR8

just make sure u put it back on that tight or itt'l probably fly off! lol.

Jeff20B

iTrader: (13)

Pele, I thought of all that before my first rebuild. It goes away after you've rebuilt a couple.

Also, you can reuse certain things even if they're on the verge of being out of spec. The rebuild may not last another 180k before needing to be torn down again, but you're going to need new bearings/side plates etc some day anyway, right? Just remember it all came out of a running engine, so if it looks good and is within spec, it's fine to reuse in a ported engine (if it won't be boosted). Just bump up the oil pressure so it can offer better protection at higher RPM and wider tolerances than stock, and it'll be ok.

By the way, this worked for me on my engine. Your results may (will) vary.