JDM B18C Transmission low rev grinds high rev smooth shifting

We may earn a small commission from affiliate links and paid advertisements. Terms

chameleon

New Member
I can’t seem to find anything on the net related to my set of tranny symptoms and hopefully my post will help someone else with similar issues.

Engine: 98+ Spec JDM B18C
Vehcile: 99 EK9

Parts (all new and installed together, used for <11,0000 km so far):

- Toda Chrome-Moly flywheel
- Competition Clutch Stage 2 - Street Series 2100 Clutch Kit
- Energy Suspension Polyurethane shifter bushing


Symptoms:

- car at complete stop, after disengaging the clutch (pedal down), it takes 2-3 seconds before I can shift into gear (ie: it’s blocked – I’m guessing the Synchros need time to synch up?)

- on occasion (say once every 2 drives), while the car is completely stopped, clutch disengaged (pedal down), shifting into 2nd gear causes the car to lurch forward very slightly (this was more evident before I changed the Clutch Master and Slave Cylinders - Slave was leaking). Can now still be felt ever so slightly.

- shifting during lower revs (ie: < 4K rpm) will increase the chance of grinding (say once every drive). The grinding duration is about for a second, before going into gear. During continuous driving the gear shift feel will change randomly from notchy , unsure , not smooth to relatively smooth / fine.

- shiting during higher revs (ie >= 4K rpm) will provide smooth effortless shifts. I have till now, not yet experienced a high rev gear grind.

- grinds / unsure gear shifting has been experienced in 1st, 2nd, 3rd, 4th gears. 5th feels a tad stiff, but since I’m in the city most often I don’t shift into 5th gear as much.

- symptoms have been this way since the new flywheel and clutch kit was installed, except that grinding is slightly more frequent now as compared to initially.

- changing the Gear oil does seem to improve the above symptoms but they will eventually come back.


Questions:

Has anyone else had similar symptoms?

Is there a way to tell if the problem is related to the Synchros or with the Clutch Pressure Plate?

I’m inclined to believe that my synchros are going bad, but I want to make sure it’s not my Pressure Plate being defective. I don’t want a defective PP screwing up my tranny if that is at all possible.

Unfortunately, from that I’ve researched it appears the only way to find out is to drop the tranny for inspection. I plan to keep driving it and replacing the gear oil again to see if symptoms are alleviated again – at least temporarily. Will be saving up for a Tranny rebuild either way.



Solutions tried:

- New Honda Master Cylinder
- New aftermarket (“Ultra-8â€) Slave Cylinder
- New Dot 4 silicone brake fluid
- Clutch fluid bled till no air bubbles appear (firm, consistent clutch pedal)
- New Honda MTF (flushed twice within 12 months)
- Adjusted CMC pushrod to provide proper disengagement clearance
- No clutch fluid leaks inside car or in engine bay
- Clutch does not slip, chatter, or make noise



Related Links:

http://en.wikipedia.org/wiki/Manual_transmission#Synchronized_transmission
http://www.clutchwizard.com/diagnosis.htm
http://www.crxsi.com/articles/read/clutch-symptoms-and-their-causes-december-2008.htm
http://www.team-integra.net/sections/articles/showArticle.asp?ArticleID=911
 
There should be a TSB about this, but there isn't, and I'm pretty sure I can help.

First off, switch back to DOT 3 Brake fluid, you don't need fancy shit for your clutch.
Second, when you bleed your clutch do it with 2 people, I know you say that your clutch feels good but I am betting there is still air trapped in the slave, here's how to get it out.

1 pull back or remove the ruber protective cover over the slave cyl on the tranny.
when you pump up the pedal and have your buddy open the bleeder, have your buddy take his hand and push the piston back even further into the slave cylinder, he will have to hold it there while he close the bleeder but I bet that he will get more air out of it.
I have seen this on MORE than 1 occasion. It SHOULD solve your problems.
let me know how it works out for you.
 
Thanks for the reply Welfare. Unfortunately, I never got notified by hondaswap (maybe I didn't have the thread subscribed (?)).

I'll give it a try next time I have a buddy around, doesn't hurt to anyways.

I found another way to do it, and that is to use a clear plastic hose (the kind you can get a home depot or whatever) and connect one end to the Slave Cylinder bleeder nipple and the other end goes back into the Master Cylinder resevoir. Of course the hose has to be a tight fit otherwise it might fall off during the process. Once everything is connected, all you have to do is unscrew the bleeder and then sit in your car and pump the clutch pedal up and down slowly (same procedure as bench bleed but we're extending the idea further with the plastic hose).

Seems to work great for me, as I get a consistent firm pedal feel. ***use at your own risk***

With that said, my above procedure did not solve the symptoms I saw, but a SS clutch line did alleviate the symptoms quite a bit.
 
Here's an update 1 year and 4 months later:
-------------------------------------------

Back 3 weeks ago my CC throw-out bearing started making noises.

Last week the bearing started to "scream", so I decided it was time to change the clutch (might as well, as I don't want to just change the bearing).

A year ago I knew I would rebuild the tranny if I were to ever change the clutch, as I didn't want to pay a bunch of labor just to find out it didn't resolve the issues I was experiencing. I was hoping the clutch would last longer, but I guess it didn't.

So last week I sent my car in for a tranny rebuild using a Syncrhotech Transmission rebuild-kit, re-surfaced my Toda flywheel, put in an Exedy Stage 1 clutch kit, and also threw in a ATS 4.9FD as well (wanted a mod thrown in there so it that it wouldn't just feel like I was only paying to fix things).

Yes it cost me an arm and a leg.

Here is what I found out after the rebuild:

>- car at complete stop, after disengaging the clutch (pedal down), it takes 2-3 seconds before I can shift into gear (ie: it’s blocked – I’m guessing the Synchros need time to synch up?)


This has drastically improved. Don't get me wrong, the synchros still need time to slow down the gears or what not, but it's definitely faster now.

PS: I also changed my OEM rubber clutch line to a SS clutch line and that help a ton (even before the rebuild) - especially with the gear lock outs. A lot of the hydraulic pressure was lost due to the rubber clutch line expanding (well it was 9 years old).


>- on occasion (say once every 2 drives), while the car is completely stopped, clutch disengaged (pedal down), shifting into 2nd gear causes the car to lurch forward very slightly (this was more evident before I changed the Clutch Master and Slave Cylinders - Slave was leaking). Can now still be felt ever so slightly.

This doesn't seem to happen anymore. I'm still in the clutch break-in phase, but this appears to have been fixed by replacing the clutch. So it appears the CC clutch was definitely not disengaging enough and thus causing clutch drag, which makes 2nd gear grab (not sure why 2nd gear specifically...)


>- shifting during lower revs (ie: < 4K rpm) will increase the chance of grinding (say once every drive). The grinding duration is about for a second, before going into gear. During continuous driving the gear shift feel will change randomly from notchy , unsure , not smooth to relatively smooth / fine.

Here's the odd part, I still witness: notchy , unsure , not smooth to relatively smooth / fine symptoms, but at a very minute level and very low frequency of occurence. Most of the time it shifts smooth like butter with an assuring feeling.

I'm not counting the time needed to warm up of the tranny/fluids within it. I'm basing my observation on having driven the car for at least 30 mins each time

With that said, I am only shifting at 2-3K rpm during the break in period. I noticed that if I take the rpm slightly higher to 3-4K rpm, it is smooth as butter, but I have not done this enough times to make a conclusion.

Will attempt it further once the clutch is broken in.


>- shiting during higher revs (ie >= 4K rpm) will provide smooth effortless shifts. I have till now, not yet experienced a high rev gear grind.

Can't comment on this yet, but I pray there will be no high rpm grinds as every synchro is brand new.


>- grinds / unsure gear shifting has been experienced in 1st, 2nd, 3rd, 4th gears. 5th feels a tad stiff, but since I’m in the city most often I don’t shift into 5th gear as much.

No more grinds at this point.


What I also found out:

1) 3-4 of the metal tabs that hold the springs on the clutch/friction disc where broken off.

The way I see it, sooner or later those springs would've popped right out. The only good thing I have to say about the CC Stage 2 clutch disc is the grip that it provides. It definitely grips hard, but I guess that comes at a cost. Possibly pretty damn good for racing, but not for DD.

2) the throw-out bearing looked like crap, but again can't base it on looks, but I know for a fact it was screaming when the car was driven prior to the rebuild.

3) My Mechanic/Tech commented that most of the syncrhos were in decent/normal wear condition, except for the reverse coller which looked a bit more abused (though shifting into reverse was never a huge issue for me). Having the used parts and examining them myself, I have to agree, the synchros don't look as bad as some of the pics floating out on the web regarding shift-grind issues. So that would explain why High RPM shifts were still smooth, which means I could've skipped the tranny rebuild temporarily - oh well.


Note: 2 years ago when I bought the CC clutch kit there were no posts about there being any problems - that or my search-skills suck-ass. Possibly the clutch kit was still new to the Honda community (?) Nowadays if you search for CC stage 2 clutch kit you can find a 15 page forum discussion that basically covers most of the symptoms I described above, along with pictures of throw-out bearings being compared, etc. But that's another story and you can read it here:

http://www.8thcivic.com/forums/mech...40-competition-clutch-issues-please-read.html
 
Last edited:
How much was the rebuild/new final drive?

I had the springs fall off my disc during a hard shift.....my trans blew. Not sure if it was the springs that caused it or the springs popped off b/c something else happened. I got a used one to replace it and never looked back.
 
How much was the rebuild/new final drive?

I had the springs fall off my disc during a hard shift.....my trans blew. Not sure if it was the springs that caused it or the springs popped off b/c something else happened. I got a used one to replace it and never looked back.

Let's see:

Labour = ~$800
Synchrotech Rebuild Kit = ~$900
ATS 4.9 FD = ~$800
Exedy Stage 1 Clutch Kit = ~$400
 
There should be a TSB about this, but there isn't, and I'm pretty sure I can help.

First off, switch back to DOT 3 Brake fluid, you don't need fancy shit for your clutch.
Second, when you bleed your clutch do it with 2 people, I know you say that your clutch feels good but I am betting there is still air trapped in the slave, here's how to get it out.

1 pull back or remove the ruber protective cover over the slave cyl on the tranny.
when you pump up the pedal and have your buddy open the bleeder, have your buddy take his hand and push the piston back even further into the slave cylinder, he will have to hold it there while he close the bleeder but I bet that he will get more air out of it.
I have seen this on MORE than 1 occasion. It SHOULD solve your problems.
let me know how it works out for you.

Welfare, I gave your technique a try today, but the slave cylinder piston is as far back as it will go when the clutch pedal is depressed with the bleeder valve opened for bleeding (ie: I didn't find any extra air bubbles or additional room in the slave cylinder piston travel).

Thanks for the suggestion regardless.
 
Glad you got it figured out! Anyways, I had that issue with my CRX and mine was improperly adjusted clutch!

Also, to help with engagement, did you scuff the gear cones to help the synchros brake faster?
 
Yeah but it wouldn't have a new clutch and a 4.9FD.
 
Glad you got it figured out! Anyways, I had that issue with my CRX and mine was improperly adjusted clutch!

Also, to help with engagement, did you scuff the gear cones to help the synchros brake faster?


Not sure if my mechanic did or not. Oh well.
 
you could have bought a new ITR tranny with LSD for the price you payed.

A USDM itr tranny with 4.4FD and no LSD is ~$2000 just for the part(s) then u need to include labour.

Then factor in the fact that the 3,4,5 gears are different from my existing jdm itr tranny.

I think the only other way to get a brand new / rebuilt jdm tranny would be either via Spoon or maybe from synchrotech if they had any in stock. But I may have considerable downtime to wait for shipping etc.

My mechanic got my rebuilt done in 2 days. And it's my DD so I need it for work too.
 
That about the same as my stock B16 trans then
 
i think you may need to change transmission fluid. sometimes that will help that. do what i do start with cheaper then go to expensive :rofl:
 
i think you may need to change transmission fluid. sometimes that will help that. do what i do start with cheaper then go to expensive :rofl:

Solutions tried:

- New Honda Master Cylinder
- New aftermarket (“Ultra-8”) Slave Cylinder
- New Dot 4 silicone brake fluid
- Clutch fluid bled till no air bubbles appear (firm, consistent clutch pedal)
- New Honda MTF (flushed twice within 12 months)
- Adjusted CMC pushrod to provide proper disengagement clearance
- No clutch fluid leaks inside car or in engine bay
- Clutch does not slip, chatter, or make noise

:ph34r:
 
What rpm are you at at highway speeds with that final drive? Like 70mph in 5th??

I'd assume it's going to be similar to my transmission; about 4000rpm.

You're both right. I was actually doing 4K rpm today in 5th. It's close to ~110 KM/h @ 4000rpm in 5th gear (or in other words 70mph).

I also re-adjusted my clutch pedal on the weekend and that has seemed to help a bit more. The clutch pedal was already adjusted by my mechanic after the new Exedy Stage 1 clutch was put in, but I thought "what the hell" and did it again anyways (ie: give it more clearance). The problem isn't completely gone but it does help to reduce it and make shifting overall an even smoother process

So I guess this all points back to a clearance issue....(?)..though keeping in mind I don't have any gear blocks/locks or clutch dragging with this new clutch. On the contrary, with the CC clutch this was a problem, as the car (at stand a still) would lurch forward when shifting into 2nd gear while the clutch pedal was depressed.

Made me re-read these articles:

http://www.teamrip.com/when_why_and_how_to_shim_pivot_ball_info.html

http://forums.clubrsx.com/showthread.php?t=512746
 
Last edited:
Back
Top