I have a 86 rx7 and I replaced the clutch recently. I found that the flywheel bolt had started to come loose when I replaced the clutch and there was so play in the flywheel. I got everything torqued back down and put back together and now the car has a vibration from 1000 - 1500 and anything above 2500 rpm.

I switched the transmission and the vibration still occurs. Also while driving if I put it in neutral before I swapped the transmissions I could rev it and it wouldn't vibrate but in gear it would. However sitting still the vibrations would occur any time I was in those rpm ranges. I have adjusted the timing and that helped a little.

The car sat for 6 - 8 months until it was warm enough for me to do this work. Any help would be very appreciated...

 

Does anyone have any ideas. I am gonna check the engine mounts but if anyone has any suggestions other than that please feel free to let me know. I would rather not have to get rid of it...

 

driveshaft?

 

I know that I will have to replace the drive shaft sometime in the near future but with the vibration happening sometimes with the car rolling and transmission engaged and only sometimes with the car rolling but the clutch pushed in or it in neutral but all the time when stopped it makes me think more along the lines of engine mounts personally.

I will be replacing the engine mounts this weekend to see if that will fix it as long as I can get a set shipped to me by then...

Any suggestions on a good set of engine mounts that are soft so that they will absorb a good bit of vibration???

 

Either stock Mazda or the Mazda Competition mounts would work fine.
The comp parts are stiffer then stock but still rubber, so not noisy and harsh.

 

You might want to try replacing your transmission mounts too.

 

The transmission mounts are very stiff now compared to what they were on the previous transmission. I checked those when I swapped to make sure the vibration wasn't from any internal failure from the transmission. Even though they are stiffer than before by 2 or 3 times the vibration isn't any worse surprisingly...

 

did you replace the input shaft bearing?

does it only vibrate while rolling or at a stop as well?

 

I was getting a ton of vibration in my 89, and I couldnt seem to track it down. So I replaced the clutch, trans fluid, diff fluid, motor mounts, trans mounts (both urethane) and I installed a new driveshaft from mazdatrix. that basically got rid if it for me although the stiff mounts are not ideal for daily driving.

 

Old transmission did not have new bearings. New one does. Both have the vibration. Vibration can happen both when rolling or when stopped, with the transmission engaged and not. Primarily it happens when the transmission is engaged rather than when it isn't though. If the mounts don't work I am rap lacing the oil and spark plugs and wires. Oil pressure is a little low and there is a noticeable miss, more so than what's normal...

 

Just found a broken engine mount on mine, worth a check. Also my drive shaft had to be replaced when I first got this 7. It was really a constant but increasingly loud vibration with pinging or metal on metal noises. Mainly after about 35mph you noticed it starting to roar. And I also found my exhaust was hitting part of the frame which made a nice vibration for me too. Hard to say though since you've done major work recently so just keep checking things you will find it. Maybe its something with your clutch job, dont know much about that yet myself but gl.

 

just had a random vibration show up in mine today my eccentric shaft bolt backed out. your issue could be there as well.

 

Are you meaning the nut for the flywheel???

 

So I finally got around to replacing the engine mounts. Still has the vibration. I have attached a couple videos so that everyone can see how the vibration is. The next thing I am going to try is plugs and wires. If that doesn't work and no one can think of what is causing the problem then I will probably end up selling the car or scraping it (especially since no one wants to buy a RX7 in my area...) since I have already sunk around $1000 into it and have only gotten to drive it maybe 10 times...

 

think we are chasing the same issue after seeing your video's. i'm still hunting right now. mine seems to be engine related in someway. my whole engine and car shake pretty badly though.

the bolt i'm talking about is your main crank bolt on the front of the engine. for the main pulley.

 

Did you check the transmission lower bushing? Its in the cross member.

 

Yep. Bushings are fine on the transmission. I know I have two different brackets because I have two different series of transmission and both have the vibration so it is not a transmission issue... :-(

Also just in case anyone overlooked it since the original post was somewhat long winded on details it happens both when moving and still.

 

what did you torque that e shaft bolt to out of curiosity?

 

factory spec is what is at now. before i have no idea what it was at. most likely was not tight enough. i showed my flywheel to my performance shop and they said it was warped so going to try changing that and the clutch out. i plan to pull the front cover to be safe and check the front keyway and counterweight.

 

new flywheel showed up yesterday dropped it off at the shop to have it sent out for balancing with the new clutch. this way i eliminate that as any source of an issue.

 

Sorry I haven't replied. My other car needs around 1100 to pass inspection and it's my winter vehicle so it's more important...

Anyway I checked the front eshaft bolt and all mounts again. Everything checks out. Still haven't figured out what the vibration is unfortunately. My winter car has a wheel bearing on its last leg so I am forced to drive the rx7 until next friday. If the vibration fries the engine then it fries the engine. I can't have my winter vehicle getting totaled but I can afford to have the rx7 blow it's engine and get rid of it.

Thanks all who contributed to try and help me. I appreciate it...

 

Sounds like a heat shield rattling. Probably just missing a couple bolts or one of the brackets rusted away.

 

sounds like a crappy non correct clutch to me, like the pressure plate is rubbing the bellhousings.

there is a lot of clutches that may fit in these trannies, but not all fit correctly. look at your old transmission bellhousing and see if there is any rub marks.

a second possibility is you mentioned the bolt being loose. did you happen to put a longer bolt in the flywheel with a nut behind it? if so, yeah it sounded good on paper, til the nut started whacking the tension bolts.

i'd bet money it is one of those 2 things.

 

Definitely not a heat sheild. All heat sheilds were removed from the car before I got it.

Also the clutch is correct. No marks on the other transmission bellhousing from when I ran it for 10 or 20 moles before switching the transmission to make sure it wasn't a transmission problem. Also no bolts were put thru the flywheel so it's not a clearance issue.

The fact that the vibration stops and comes back depending on rpm means it can't be a clearance problem as something that is having a clearance issue would not just magically stop hitting at certain rpms. Just saying.

 

untrue, while there isn't much thrust play in the engine your e-shaft does walk depending on engine load and RPMs, so if something is barely interfering with the rotating mass it may just barely be touching it to the point that it goes away when the shaft walks the other direction. but it's up to you to figure out what is touching what in that scenario. any collision witness marks may even be very small and difficult to see.

you ruled out the tranny and by the sound of the knocking vibration in the video it certainly sounds like an interference issue to me. in math you add things up, on paper you have to think of what you did in steps before the problem arose and take those steps backwards.