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My concern would be if the bolt thing was tightened too tight and pulled the pulley/boss assembly too far forward on the e-shaft, would some threads on the bolt or e-shaft be stripped?
So can the trigger wheel be moved away by inserting 1mm washers between the pulley's and the boss?
So you do not have to remove the bolt.
The concern for the possibly pinched needle bearing would remain.
I have wedged a big screwdriver between the lip of the pulley and the water pump housing to create some leverage (might not be the best idea I've ever had but couldn't find a different point to get leverage) to see if there movement. Again, there is no lateral (or back to front movement). Here's a short recording again: https://streamable.com/bh7tss.
I have not yet taken the pulley off, but I can see that it has been off at some point because the markings of where bolts where previously mounted
That video is a repeat of the other, but this site is causing me grief today....and maybe it's at my end. From my perspective, the terminology may be tripping us up, you're really only looking for longitudinal play (along the axis from front to back). Basically the stack you're looking at is between the front counterweight and front stationary gear, two hardened chromed washers at either end, 2 axial thrust needle bearings(torringtons), a selectable spacer and another large plate the axials bear against in the middle. Not unknown for eccentric shafts to break and that might explain it as well.....if you had someone phantom driving it on the sly!
The locking device may have come from the previous engine if there's been a rebuild, rather than a swap, lacking an engine number on the front plate is often a telltale for the Japanese. V1 engines from front cuts I've come across have had the locking gizmo in each case, but maybe retrofitted? In any event, since it was running ok before, unless there's something that should be very obvious on the exterior, I think it's inevitable removal and disassembly will be required. An ugga-dugga with a bit of grunt will make dealing with the front bolt easier.
If you have the factory pull type clutch, when you have the pedal depressed, it will remove all the slop. There should be no movement. Now take the board out, remove the front pulley’s and trigger wheel. Use a pry bar on the back side of the front hub and wedge it against the water pump housing. You don’t need to go cave man on it just some light pressure. (Technically, you should be able to pull it back-and-forth with your hand) There should be some end play. Should be a few thousands at min. If you could use a dial indicator with a magnetic base would be best. If you do not have any end play, you have a front stack issue. It could be that the end play was set to tight or the roller bearing dropped down and is now wedged. If it’s the first, it will fail in short order, if it’s the second it already has. Hate to be the bearer of bad news but even if you made adjustments to the cas sensors by grinding down the mounting area ( you should not ) or removed the front hub and put a shim in, you would just being buying time.
That video is a repeat of the other, but this site is causing me grief today....and maybe it's at my end. From my perspective, the terminology may be tripping us up, you're really only looking for longitudinal play (along the axis from front to back). Basically the stack you're looking at is between the front counterweight and front stationary gear, two hardened chromed washers at either end, 2 axial thrust needle bearings(torringtons), a selectable spacer and another large plate the axials bear against in the middle. Not unknown for eccentric shafts to break and that might explain it as well.....if you had someone phantom driving it on the sly!
The locking device may have come from the previous engine if there's been a rebuild, rather than a swap, lacking an engine number on the front plate is often a telltale for the Japanese. V1 engines from front cuts I've come across have had the locking gizmo in each case, but maybe retrofitted? In any event, since it was running ok before, unless there's something that should be very obvious on the exterior, I think it's inevitable removal and disassembly will be required. An ugga-dugga with a bit of grunt will make dealing with the front bolt easier.
Cheers, I think this video does show that front to back play: https://streamable.com/bh7tss. Well, there is none but that's what I was looking for, to see if I could move that pulley/trigger wheel assembly forward, I tried this at a couple of points.
Unfortunately I didn't get to take the pulley off tonight as I had to sort some stuff out for work, but I'll try again tomorrow and let you know. Regarding the locking device, it does seem that's consistent with the S7 later engine which is in the car so I'll use those resources as a reference (the same ones @Redbul posted) .
Originally Posted by gdub29e
If you have the factory pull type clutch, when you have the pedal depressed, it will remove all the slop. There should be no movement. Now take the board out, remove the front pulley’s and trigger wheel. Use a pry bar on the back side of the front hub and wedge it against the water pump housing. You don’t need to go cave man on it just some light pressure. (Technically, you should be able to pull it back-and-forth with your hand) There should be some end play. Should be a few thousands at min. If you could use a dial indicator with a magnetic base would be best. If you do not have any end play, you have a front stack issue. It could be that the end play was set to tight or the roller bearing dropped down and is now wedged. If it’s the first, it will fail in short order, if it’s the second it already has. Hate to be the bearer of bad news but even if you made adjustments to the cas sensors by grinding down the mounting area ( you should not ) or removed the front hub and put a shim in, you would just being buying time.
Check that and let us know your findings.
~ GW
Thanks for that. If it's f-ed, so be it, I guess I'll just have to deal with that, I won't try to get the cas to fit or start messing about with shims. I'll try to get the pulley off and see how we go.
The fact that you have zero clearance on the CAS sensors is kind of a dead giveaway. Consequently, the dead airspace for them between the trigger wheel is roughly the same height as the roller bearing on the front stack. It’s possible that somebody had that apart for some reason, tho it’s really hard to speculate.
Reitangle,
Since I got a PM saying you were trying to contact me, I'm replying here. Unfortunately, I have no knowledge of anything that hasn't been already posted, and I am still on my original engine which has never been apart.
So, good luck figuring this out.
Also you can remove the pulley with just removing the 4 10mm bolts. That will remove the pulley and crank trigger wheel and leave the pulley boss behind.
The only time when it's appropriate to remove the big 19mm front pulley bolt is the engine is out of the car and you're fixing to pull the front cover. If you remove it and just put it back it's possible the needle bearing could drop and get pinched.
Also you don't want to try and remove the front cover in the car. You have to pull and re-seal the oil pan and trying to do that in the car is a NIGHTMARE. You are time and effort way ahead pulling the engine.
I will say on my FC on my very first engine rebuild I pinched the needle bearing and the E-shaft slopped back and forward a few MM's when pushing the clutch down. With the FD's pull clutch I don't know if it would do the same thing. There should be a VERY small amount of play but big slop is not OK.
Also I don't know if the pullies, trigger wheel, or front hub could be different on 96+ cars or if someone tried to swap that as part of the conversion.
Finally I bought a 96-98 used JDM engine pull out a number of years back to part out. I snagged the newer smaller MAP sensor and put it on my car - 93-95 stock ECU at the time, ran just fine, and with the PFC it also reads fine and is dead accurate. I believe the scale is the same, they just got a new supplier or something. This could have changed in 99 but this was my experience. Engine was definitely a 96-98, had the aluminum Y-pipe, black box, etc.
Reitangle,
Since I got a PM saying you were trying to contact me, I'm replying here. Unfortunately, I have no knowledge of anything that hasn't been already posted, and I am still on my original engine which has never been apart.
So, good luck figuring this out.
Oh that's interesting, I didn't try and send any PM, I think I may have just liked your message. What does it say 😮?
Originally Posted by DaleClark
Also you can remove the pulley with just removing the 4 10mm bolts. That will remove the pulley and crank trigger wheel and leave the pulley boss behind.
The only time when it's appropriate to remove the big 19mm front pulley bolt is the engine is out of the car and you're fixing to pull the front cover. If you remove it and just put it back it's possible the needle bearing could drop and get pinched.
Also you don't want to try and remove the front cover in the car. You have to pull and re-seal the oil pan and trying to do that in the car is a NIGHTMARE. You are time and effort way ahead pulling the engine.
I will say on my FC on my very first engine rebuild I pinched the needle bearing and the E-shaft slopped back and forward a few MM's when pushing the clutch down. With the FD's pull clutch I don't know if it would do the same thing. There should be a VERY small amount of play but big slop is not OK.
Also I don't know if the pullies, trigger wheel, or front hub could be different on 96+ cars or if someone tried to swap that as part of the conversion.
Finally I bought a 96-98 used JDM engine pull out a number of years back to part out. I snagged the newer smaller MAP sensor and put it on my car - 93-95 stock ECU at the time, ran just fine, and with the PFC it also reads fine and is dead accurate. I believe the scale is the same, they just got a new supplier or something. This could have changed in 99 but this was my experience. Engine was definitely a 96-98, had the aluminum Y-pipe, black box, etc.
Dale
Some quite useful info there, thank you! I'll start by just removing just those 4x 10mm and report back. In terms of the slop back and forth, I haven't been able to observe any 😮. I'll get my wife to engage/disengage the clutch and see if I can spot anything.
^^At this stage, short of a Breaking Bad style electromagnet hidden in the donk, it's entirely a mechanical problem to solve. If he's got a haltech for later use, probably wiser to spend the dosh on something other than a 2 bar sensor.
Earlier in the thread, he also did say the voltage output v pressure was the same based on the two workshop manuals, which seems logical for an OEM. Other than bad repinning of the front harness, if it hadn't thrown codes during earlier use, that seems to confirm compatibility.
Alright, bit of an update. Finally had an opportunity to test with two people, and found something interesting, following these steps:
With the clutch pedal released I could get the pulley/eshaft to move forward by manually wedging it forward. The spacing between the trigger wheel and sensor is the perfectly within the 1-2mm spec. A 1.5mm (confirmed with digital calipers) thick zip tie fits snuggly in between.
When the clutch pedal is then depressed, the pulley/eshaft move back again and the gap between the trigger wheel and sensor closes up again to about 0.1-0.2mm (guesstimate).
And then when the clutch pedal is released again, the eshaft/pulley stays in place and does not move back at all.
To summarise, clutch pedal depressed = pulls the eshaft/pulley back, clutch pedal released = allows for movement of the eshaft/pulley forward but only manually, not automatically.
As I am not super familiar with the whole needle bearing business, does this mean anything to someone? Instinctively it feels like the 'play' it should have is correct, bu mechanically something is stuck or has too much resistance or something for it to spring back. Or is the eshaft not supposed to be moved at all with clutch (dis)engagement?
Last edited by Reitangle; Nov 14, 2024 at 04:03 AM.
Reason: Removed reference to now deleted post.
One disassembled here, just a few tonne of metal and equipment preventing access to it! Funnily enough, an auction tonight over in Alexandria had something better than the usual chinese supercheap style quality, plus nice engine stands. You need to start to think about rebuild kits now.....the joys of rotary ownership.
Shew! I just watched the video and it’s pretty clear. That endplay is huge. It’s almost like the bearing is totally gone now, or smashed. To put it in perspective when I set end play on those I normally target 3 thousands. The good news is you’ve found the problem and hopefully caught it before it does further damage. Bad news, you might as well pull the engine. Doing that job in the car is a royal pain. This may be an opportunity to clean up some stuff on the engine and on the engine bay also. Do you have a FSM ?
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Yep, 100% you have an end play problem. As stated most likely the engine was assembled with the bearing crushed or someone did some work (like removing the front pulley) and that ended up crushing the needle bearing.
When they get crushed, you have zero end play. Once the motor is run and that bearing is chewed up you get the slop.
Also I see in the video when you pull the zip tie out the crank angle sensor moves a good bit - don't know if it's broken or it's just not fully bolted down for testing, but that should be rock solid.
So....you have to pull the engine. You have a few options:
- Pull, drop oil pan, pull front cover. Find all what is damaged, replace and properly re-assemble the front cover and properly re-seal the oil pan. Engine back in, done.
- Pull the engine and do a full rebuild/refresh. Go through everything and get it all new and happy.
- Pull and swap a known good/fresh rebuild/new engine in.
It really depends on your budget and what you're looking to accomplish and also just the general state of the rest of the engine. I will say a LOT of things are SO easy to do with the engine out and on an engine stand.
I think I mentioned that I crushed a needle bearing on my first rebuild on my first FC back in '96 or so. The rest of the engine was fine, just needed a new needle bearing, spacer, and maybe the thrust washer. But the big thing is you don't know the state of the rest of the engine - does it have shot bearings? Apex seals worn down to a nub?
Hate that it's bad news but now you have an answer at least!
Thanks everyone for your help, expertise, and for guiding me along the journey. It has massively fast tracked my understanding of the RX-7 and rotary engine.
Hate that it's bad news but now you have an answer at least!
This 👆 probably sums it up best! I am not super worried about the engine needing to be out, sure it's a hassle, especially because the car is a complete non driver at the moment and I can't easily take it to a shop, but that's nothing that can't be sorted out! But I did buy this car thinking that it might need an engine rebuild (at least at some point), this was somewhat reflected in the price and my thinking was I can either buy a more expensive car that an importer/seller told me had a good engine, or take an unknown and have it rebuild so it's a known good engine. The whole reason I didn't immediately pull it out was that the compression was quite good and I thought it was 'just an electrical problem'.
In terms of options, I think I'll go for a rebuild/refresh. Sadly, I don't really have the facilities to do this myself, so this is probably the one thing I'll have to outsource. There's quite a big list of rotary specialist in the greater Sydney area so I'll start ringing some shops straight away.
If anyone has any suggestions for either, specialists in the Sydney area that they might recommend, or even those dreaded (but lovely) 'whilst you're in there' things that I am best to change or upgrade with the engine out. Let me know!
Unpopular opinion. If the engine has good compression, you can simply repair the front stack, clean out the pan and move on down the road. Sometimes the rabbit hole can run deep. It has caused more than one of these car’s to spend years off the road instead of being enjoyed. Just some food for thought.
Thanks @gdub29e , food for thought indeed! I'm inclined to just have everything sorted because I don't know the history of the car, and the current space I've got available at the moment to work on the car isn't great. Since that's one of the biggest hurdles, I'd want to make sure that once the engine's out, it doesn't need to go out shortly again in the near future. But I'll keep that in mind and let some of quotes I can get from specialists in the area be a decision driver for that as well.
Last edited by Reitangle; Nov 14, 2024 at 09:22 PM.
Reason: Wording
If what gdub29e suggests works, you can then take your time accumulating a set of components for building a spare engine, when you see the various parts come up for sale at below dealer retail.
I am currently having three motors build from parts I have accumulated in this manner.
Can the oil pan be changed out by dropping the front subframe assembly instead?
