flywheel torqued down, now rebuild doesn't spin easily?
 

I finally got my rebuild tension bolts torqued down last night. I assembled the front stack, spun it over a few times and checked the endplay. Everything seemed great.

I put the front cover on, reassembled the stack, and then put on the flywheel. Now it doesn't turn over easilly. I can bearly spin it by grabbing the flywheel. Putting a breaker bar on the front bolt makes it a little easier, but its still difficullt. It feels much harder to turn than when I took it apart.

When I loosen the front bolt, it goes back to how it should be, spins fine by grabbing the flywheel.

When I took of the flywheel, same thing.

I'm 99% sure its not a caught spacer, because I took it apart and the spacer and bearings were fine. The bearing showed no signs of being caught.

Without the flywheel or front bolt on, it turns with a normal amount of force. I spun it over about 10 times to make sure side/corner/apex seals weren't caught or binding before I added the flywheel, so that isn't an issue.

Searching revealed this thread:
https://www.rx7club.com/showthread.p...ebuild+turning

Same deal as me, but I know that the thrust washer is in there. I cant say for sure that the chamfered edge is oriented correctly, but that shouldn't be causing this, should it?

Also, I replaced the rear stationary gear seal, where the flywheel attaches. Would this seal being new cause this? Does it need time to break in?

When the flywheel is added, all float goes away. Without the fllywheel, float is within spec with a K spacer.

Any thoughts?

You are suppesed to torque the front bolt (19mm) first. I am not sure and I am just thinking out loud but maybe you are pulling the E-shaft back by trying to torque the flywheel first.

Also the thrust bearing ( the one inside that first spacer) slips down if you take the spacer out. (least mine did) I thought it strange that Bruce T put that spacer in when he did. I didn't listen to him and put it all together the way I thought it should be and the spacer was grabbing just the edge of that bearing. Messing everything up. When I took everything apart I re-installed it the proper way and things went alot better

Hmm, does the order of torquing things really matter? I'll try doing it that way tonight.

The FSM has the flywheel going on first. Right after the tension bolts are torqued down.

had the same axsact problem when i did the auto to 5-sp swap double check the flywheel key make sur its on correctly

The rear main seal has no effect on turning ability.

Putting the flywheel or front pulley bolt on first/last has no effect...I often install the flywheel first if I'm doing a longblock, before I even install the front cover junk. Or, if it's a shortblock being shipped out, I obviously do just the front cover and the flywheel gets put on later...in either case it works fine.

Any chance something under the front cover is binding you up? Like a counterweight rubbing a bolt or casting, or the oilpump dragging for some reason? Does this happen only when you put the cover on, or only when the pulley bolt is tensioned? Checked your endplay once the front bolt is tightened?

jarring the e-shaft without the front hub tightened down could have caused one of the thrust bearings to fall off of the spacer.

the front cover has been off ever since this came up. It does it regardless of the fron cover. Also, the oil pump is off, but the drive sprocket is on the front stack, obviously. Still is hard.

It happens when both the flywheel and front bolt are torqued. If just the front bolt is on, end play is good, and the engine spins with the correct amount of force. When the flywheel is lightly bolted on, everything is still good. tighten down the nut, and the thing locks up again. Loosen the front bolt, it spins fine again. With both torqued, there is NO endplay.

The bearing and spacer are not caught. I've set and reset them 3 times now, and the spacer has never caught the bearing, nor has the bearing shown any damage, bent etc.

I tried the idea of the flywheel key, and there was no effect on removing it completely, so it's not caught.

Thanks for the help guys, I'm stumped. Keep em coming.

Are you sure your rear stationary gear is fully seated into the rear iron?

IT sounds like the flywheel is being obstructed by something when tightened down. Perhaps check to see that your bearing is properly seated into the rear stat gear, and that the rear stat gear is properly seated into the engine, and that no stat gear bolts are sticking out or anything.

See any metal shavings on the flywheel or the stat gear/bearing/rear main seal assembly?

I can honestly say that I've never encountered such a problem in all my rotary building and assembling adventures.

I agree with your assesment Kevin. It makes sense to me for the flywheel end of things being the problem.

Well, I'll take a closer look at the stat gear tomorrow. It did take a bit of convincing to get the gear in. I had to tap it in with a block, but I'm pretty damn sure that the thing is in there and bolted properly. I'll pull it out tomorrow and reset it.

Your right, I am sorry for speaking out incorrectly. The Bruce T video had it backwards. He put a flywheel on just to hold everything still while assembling the front. way later in the video he puts the flywheel on. I hope I didn't make things harder for anybody.

Sklylone,

Any update??

I'm going to pull the rear stat gear tonight. I'll be sure to let you guys know how it comes out.

Ok, I pulled the stat tonight, it did not solve the problem, but maybe it got better a little? I think so, but not much.

I screwed up (just a little). I forgot to remove the old rubber o-ring from the gear. I place the new one on top without thinking about it. It prevented the gear from fully seating to the iron. It was only noticably by getting down and looking level wit the gear, the protrusion wasn't much at all.

The gear fits very tight. Should it? On the Bruce T video, it just drops right in. Mine needs tapped in with a block, and its even more trouble to remove.

I never checked if the bearing was protruding, because it was never removed. I should look at that next. I'm at a loss, but am convinced that the stat gear is where the problem lies. I could only work on it for a little bit tonight. I'll try again tomorrow night.

My stationary gear was tight as well. I had to really work it back and forth to get it in.

So you put the new o-ring on top of the old o-ring?? Both were on there??

The old one was compressed down and I didn't notice it. They were both on there. When I saw it, I though this was the problem! No wonder no one else has any idea whats going on, they never did anything that stupid before.

lol :)

Don't say stupid. its just funny. Did you get it back together or give in for the night??

IT's common to have to tap them into place...and use the bolts to pull them in all the way. I'd say that was your issue there. BUt, we dont know until you tell us ;)

OK, so I'm at a loss, here.

I pulled the rear stat gear again. I ran some sandpaper around the rear flange, and along the housing. tapped it back in, torqued it down, same thing. I went to the front, changed the thrust bearings to the used ones, checked the front stat gear, sanded, torqued down, same thing.

Then I got serious.

I unbolted the flywheel, and hand tightned it down. I put on the wrench (2 foot breaker bar) and tightened it as much as I could. Now I brought out the 5 foot brecker bar, and gave it a half a spin and checked the play. Everythings fine. Another quarter spin. Still good. Another half spin. Float is gone, but I could still move it fine.

So, I think I just don't know my strength and have been over torquing the thing? Is that possible, to over tourque the flywheel and have it bind up like this?

I hope thats the answer. I coated the nut in loctite and tightened it down to just before it started to bind. Good enough? I think I'll rent a 600 lb tourque wrench on Monday and check things out, just to be sure that its within spec.

No, I tighten mine down routinely with my 450ftlb gun (forward power) without a torque wrench, and never have any binding.

Wherever the source of the binding is, you could probably see a bit of scarring on the metal to metal contact surface. I would find that surface.

This is truly odd...I'd like to hear the conclusion to this whenever it's found. I wouldnt proceed without finding it.

IS there any chance that you left out one of the small spacers on the front stack? I could see how that would pull the shaft forward and allow contact between the flyweel and stat gear.

No the front stack is all there. Washer, bearing, spacer,plate, bearing, washer, counter weight, oil pump gear, cas gear, pulll boss.

I even started trying wierd things. I changed the pulley boss, the flywheel nut, I compared the rear stat to another to see if there was any perceptible differance, or if the bearing had some how moved.

Just to clairify, there is no way there could be anything internally wrong here is there? In my head no, since this has nothing to do with the the legnth of the block, and the only thing that should be contacted an affected is the front stack or flywheel.

I did not want to suggest it, but it is somewhat possible there is an internal issue, such as a slipped sideseal or apex corner piece that has lengthened the back pieces of the engine enough to allow interference between stat. gear and flywheel. I'd like to see some close up, high res pics of the stat gear/e-shaft as it sits now to compare to what I normally see.