Mazda Rotary Club

General => General Technical => Topic started by: Gateeast on July 07, 2007, 10:58:34 PM

Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 07, 2007, 10:58:34 PM
I believe my FD has got a rotor arm stuck no compression at all, can it be freed and all will be good?  If so, how would I free it please?
Title: Can a stuck rotor be freed with no probs?
Post by: elford_tim on July 08, 2007, 07:24:33 AM
Sorry, it\'s got *what* stuck?

If a rotor is stuck, it won\'t turn over. If you have no compression, can you be a bit more specific? On how many rotors, for starters? And one how many faces of those rotors?
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 07:30:48 AM
One rotor but not sure how many faces as the engine is still in the car.
Title: Can a stuck rotor be freed with no probs?
Post by: elford_tim on July 08, 2007, 07:48:07 AM
If you\'ve had a "proper" compression test done, you should have a printout giving you the compression values on all three faces...

AFAIK there\'s no magic rotary-fixit fluid (you\'d be a rich man if you could invent one). If you have low compression on a rotor the sensible thing is to pull the engine - you don\'t know what\'s causing it so you may well do more expensive damage if you don\'t.
Title: Can a stuck rotor be freed with no probs?
Post by: grinder on July 08, 2007, 10:15:51 AM
they can get stuck ( or so i have read )

the apex seals can get stuck with carbon if they motor hasnt been run for a while ??

i tried this with my old cab ( it seemed to work a little bit but not loads )

1 - remove all the plugs
2 - get some ATF fluid
3 - put 5ml in the top spark plug hole
4 - rotate the engine 1 turn
5 - put another 5ml in
6 - rotate another turn
7 - put 5ml in
8 - what you should have is 5ml in each chamber
9 - leave over night
10 - remove the EGI fuse and crank the engine to remove th ATF fluid
11 - put the plugs back in
12 - put the EGI fuse back in
13 - start the car
14 - the ATF should eat a lot of the carbon build up and free off the stuck tip

dont blame me if this doesnt work - but i have read that you can do this

i have also heard ( and seen a vid somewhere ) that you can pour a can of coke into the engine to give it a bit of a clean

have a search on rx7club.com - they seem to like the ATF menthod ( Auto Transmission Fluid )

like i said - dont blame me if you really kill the engine - but if its already dead you cant hurt it much more !!

Stu
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 10:39:24 AM
Thanks Stu

My car is obviously not well but not sure its a tip/seal gone not loss of fluid no really bad exhaust emissons no strange broken/grinding noises - it does not idle but unlike other people no more power at higher revs it is just like driving a car with one rotor.  But I suppose the question is if one were to be stuck would the engine not seize?
Title: Can a stuck rotor be freed with no probs?
Post by: kev-yorks on July 08, 2007, 10:50:11 AM
No the engine won\'t seize with a stuck apex seal it just means it can\'t follow the profile of the housing and keep a seal (hence no compression) the ATF trick can work another one if you can get to the exhaust ports is to manually work the seals in and out as they align with the exhaust ports. Carb cleaner is more agressive than ATF if they are really stuck. One word of warning though just because it spins and you get no noises from the motor it doesn\'t mean you\'ve not lost a seal. There\'s certainly no harm in trying to free them just in case it is something stuck. I\'d give it a oil change afterwards though if it does cure it.
Kevin
Title: Can a stuck rotor be freed with no probs?
Post by: Carl on July 08, 2007, 11:06:41 AM
Sounds like seals broken to me,as opposed to stuck.
That would mean full rebuild.
What actually happened in the build up to this?
Regards
Carl
Title: Can a stuck rotor be freed with no probs?
Post by: grinder on July 08, 2007, 12:08:21 PM
do the poor mans compression test then - its the cheapest way if you have a compression tester ??

failing that - the even cheaper way is to remove the plugs , pull the egi fuse and crank the engine - get someone to have a listen and see if they can hear 3 even "phush" from the spark plug holes

like carl said - what happened during the build up to this ?
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 02:21:49 PM
Done the listening thing - no sound at all.  I know what to listen for having deflooded a car before.  Basically doing 60 ++ mph eased off for a dead badger in the middle of the road.  Accelerated again (full throttle). The end - literally.
Title: Can a stuck rotor be freed with no probs?
Post by: 20B_boy on July 08, 2007, 03:42:43 PM
You dont get any \'chugs\' at all? which rotor is this, front or rear? both? :eek:
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 04:05:09 PM
Front no sound at all.  Rear one is fine.
Title: Can a stuck rotor be freed with no probs?
Post by: 20B_boy on July 08, 2007, 04:44:24 PM
Quote from: GateeastFront no sound at all.
Think its unlikely that its some tihng stuck mate as you have zero chugs. Sounds like the contents of the front rotor housing is shrapnel :(
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 04:47:41 PM
That\'ll be the fifty miles driven thereafter then !
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 09:44:54 PM
Quick thought, if the rotor has become shrapnel why no sound of all this metal going round and round?
Title: Can a stuck rotor be freed with no probs?
Post by: Jit on July 08, 2007, 09:57:23 PM
prob cos bits of shrapnel are wedged in the housings/rotors/plates and the rest has gone thru the turbos and ate the blades....and then gone out thru the exhaust
Title: Can a stuck rotor be freed with no probs?
Post by: Gateeast on July 08, 2007, 10:06:14 PM
Turbo still boosting to some degree can hear the blow off valve
Title: Can a stuck rotor be freed with no probs?
Post by: Carl on July 08, 2007, 10:30:51 PM
No sound cos it jams remaining parts into the rotor grooves and the rest goes out of exhaust ports.
Regards
Carl
Title: Can a stuck rotor be freed with no probs?
Post by: mpk490p on July 09, 2007, 09:01:38 AM
just sounds expensive too me, either way it gonna have to come out like a bad tooth!

Mark