Honda D Series Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
230 Posts
Discussion Starter #1 (Edited)
Hey guys,
So I'm having some issues shifting in RPM and now also in low RPMs
Some background: I bought the car with a slippy worn clutch. I replaced it with a new action clutch 1MS and a lightweight flywheel (forgot the brand).
Ever since I remember the car, it was hard to shift gears in high RPMs and sometimes I got it grinding.

I replaced a couple of S20 transmissions since than, and currently I have a fully rebuilt S40 tranny with new bearing and synchrotech carbon synchros. I still had a hard to shift issues on high RPM but it was way better than the previous trannys.

Recently it stated grinding sometimes, and on the last ran I grinded 2nd and 3rd gear. That's the time I decided to adjust the pedal free play, in order to give it a bit more of pedal travel, in case the clutch isn't fully disengaged while clutch pedal is fully depressed. So I reached the pedal area underneath the dashboard, and saw that the master cylinder is leaking. So I replaced the cylinder, bleed the air and adjusted it for a minimal pedal free play. Now the clutch is engaging way higher, but I fill that shifting into gears goes much harder now, even in low RPM. I sometimes the filling is like the shifter gets into a gear in like "two steps". Sometimes while standing, when trying to shift into a random gear, the shifter stuck in the "first step" with clutch fully depressed of course, so I keep holding the shifter in this position trying to push it in, revving the engine to 4k rpms and the gear slides right in.

I don't know if the last problem came out of the last grinding event which fucked something into the transmission or because of the new master cylinder. Is there any way to check it? May the new master cylinder is faulty? And for the original problem (hard to shift in high RPM), Is it possible that all the headache was because of the leaky master cylinder (I don't know when it started to leak, but I think it wasn't leaking when I installed the clutch)? Any chance that the clutch is faulty from the begging (isn't fully disengaging)? I want to mention the the clutch pedal is pretty stiff and the clutch is holding the power well.

Any help / thoughts will be appreciated.
 

·
BATSLOMAN GIVES NO FUCKS.
Joined
·
3,938 Posts
how are the engine mounts?
do you have the correct linkage?
bitch pin installed?
shifter bushing in good condition?
clutch fork in good condition?
correct and working slave?




*turns on bone signal*
 

·
Registered
Joined
·
5,847 Posts
Do another pedal-shaft adjustment on the master. You do not want it right at the top of engagement, which seems like how it is behaving.

I generally start with the clevis at the very end of the shaft, and move inward in 1/4 inch distances until the pedal feels good.

If the clutch has been dragging a lot over the years, it certainly has been eating at the shift forks inside the tranny during shifting.


What fluid are you using? If using honda MTF fluid, STOP!!!

current generation honda MTF is too thin.

I use one bottle of pennzoil (GM) synchromesh, and a bottle of cheap mobil 5000 10-30 motor oil.

My accord shifts like silk after replacing whatever was in it originally.


EDIT when the pedal adjustment puts it at the very top, you actually are over-extending the master. Do a quick test, use the cluthc pedal only halfway, see if it shifts differently. If it does, we are onto something!

Transzex/ Mista Bone is the local expert, along with Aquafina and a few others. They will chip possibly
 

·
Registered
Joined
·
4,167 Posts
Mounts good?

What fluid?

How long did you drive it while it was grinding?

Who rebuilt the transmission?

Was anything other than bearings and synchros replaced?
 

·
Registered
Joined
·
230 Posts
Discussion Starter #5 (Edited)
how are the engine mounts?
In a good condition. The tranny back mount is new and filled with polyurethane to make it stiffer.
do you have the correct linkage?
The car came out of the factory with manual gearbox so I guess the shift linkage is correct
bitch pin installed?
What is that? the ones between the linkage and the tranny? If so, yes it's there
shifter bushing in good condition?
Probably fine because the shifter feels very tight with no play
clutch fork in good condition?
Is there any way to check it? Generaly it looks fine
correct and working slave?
I replaced the slave shortly after the master change with a new one, even though the previous one wasn't leaking. No change.



*turns on bone signal*
Do another pedal-shaft adjustment on the master. You do not want it right at the top of engagement, which seems like how it is behaving.


I generally start with the clevis at the very end of the shaft, and move inward in 1/4 inch distances until the pedal feels good.
What do you mean by saying "Pedal feels good"? What Should I feel?
If the clutch has been dragging a lot over the years, it certainly has been eating at the shift forks inside the tranny during shifting.
Since I installed this tranny on the car, I didn't use it too much, so I really hope nothing bad happend.


What fluid are you using? If using honda MTF fluid, STOP!!!
current generation honda MTF is too thin.
I'm using honda MTF :/ I noticed it's really thin, but this is what I've been advised :/

I use one bottle of pennzoil (GM) synchromesh, and a bottle of cheap mobil 5000 10-30 motor oil.
My accord shifts like silk after replacing whatever was in it originally.
Can I use any 10-30 oil? should it be synthetic or semi synthetic? Does it matter what additives it contains?


EDIT when the pedal adjustment puts it at the very top, you actually are over-extending the master. Do a quick test, use the cluthc pedal only halfway, see if it shifts differently. If it does, we are onto something!
I'll give it a try. Just curious, Isn't more pedal travel=Better seperation of the disk clutch and flywheel?

Transzex/ Mista Bone is the local expert, along with Aquafina and a few others. They will chip possibly
Mounts good?
Yes
What fluid?
Honda MTF
How long did you drive it while it was grinding?
It didn't happend too much. The grinding occured only in some high RPM shifting. Sometimes the gear just seemed "locked" and I had to wait for the engine revs to drop a bit to get it in, and sometimes it just grinded, probably I've tried to shift more aggressive

Who rebuilt the transmission?
I did

Was anything other than bearings and synchros replaced?
Any part that seems a bit worn was replaced, and taken out of another tranny after a careful inspection. I've replaced a couple of gears generally.
Answers in red.
 

·
Registered
Joined
·
230 Posts
Discussion Starter #7 (Edited)
The tranny housing is S40. I've replaced all ball bearings, all synchros to carbon synchrotech synchros, I can't remember exactly but I mixed out some parts between several S20 trannys I had, Like main shaft and counter shaft, gears (sets of course). Shift forks are the original steel ones, I had the 3rd gear fork welded and flatened out as it was pretty worn. Everything was in great condition. Bench test was pretty smooth. Driving it was really fun, it shifted like a butter. The only issue was high RPM shifting.
Now it feels different, gears comes in more with much more effort and less smooth, like in two steps, instead of one clean step. I wonder if it's something related to the clutch/cylinders, or a mechanic problem inside the tranny.
 

·
Registered
Joined
·
230 Posts
Discussion Starter #8
Do another pedal-shaft adjustment on the master. You do not want it right at the top of engagement, which seems like how it is behaving.

I generally start with the clevis at the very end of the shaft, and move inward in 1/4 inch distances until the pedal feels good.

If the clutch has been dragging a lot over the years, it certainly has been eating at the shift forks inside the tranny during shifting.


What fluid are you using? If using honda MTF fluid, STOP!!!

current generation honda MTF is too thin.

I use one bottle of pennzoil (GM) synchromesh, and a bottle of cheap mobil 5000 10-30 motor oil.

My accord shifts like silk after replacing whatever was in it originally.


EDIT when the pedal adjustment puts it at the very top, you actually are over-extending the master. Do a quick test, use the cluthc pedal only halfway, see if it shifts differently. If it does, we are onto something!
Can you explain a bit more about it?
I tried today to adjust shorten the master rod a little bit and I did notice a difference in gear change, it goes a bit more smooth. Now the clutch is engaging really low, so maybe I shortened it too much. I'll try to extend it a bit and see if it makes any difference.

Transzex/ Mista Bone is the local expert, along with Aquafina and a few others. They will chip possibly
 

·
Registered
Joined
·
4,167 Posts
Did you shim the mainshaft?

If you mixed and matched gears you're going to have issues.

What was the thickness of the fork after welding? Was it hard chrome plated?
 

·
Registered
Joined
·
230 Posts
Discussion Starter #10 (Edited)
No, I didn't shim the mainshaft. I can't remember the exact thickness of the welding of the 3rd fork, but it was at the same level as the rest of the fork. It wasn't hard chrome plated.

UPDATE:
I did try a method I found acroos the net of testing whether the clutch disangages fully or not.
The method is pretty simple. Putting the car on level ground, and while standing with clutch pedal depressed all the way down, revving the engine - If the car moves, the clutch doesn't disengages fully.
So the car didn't move, but a surprising thing happend, while revving the engine (5500 rpm) with clutch pedal depressed, I could shift into all gears easily without any effort! All the gears came up smooth as butter.
So what is going on? What can lead to this weird problem?
 

·
Registered
Joined
·
230 Posts
Discussion Starter #12 (Edited)
Your'e right, The right thing to do is to shim the mainshaft. I didn't know it was so important back than, while doing the job. However, I really hope the tranny will survive and I'll find a solution for my specific problem, without having to take it apart again.

I bleed the system following the intsructions of the honda technical manual, using the slave cylinder bleeder bolt. At the end of the process, no air came out of it, pedal is firm. I used a lot of dot 4 fluid in the process in order to make sure there is no air in the system and all the fluid is clean and fresh.

However, I'll try to bench bleed the master cylinder just to make sure.
 

·
Registered
Joined
·
230 Posts
Discussion Starter #13
UPDATE:
So I replaced the clutch master cylinder once again, and bench bleed it. It probably made some kind of difference, but not much.
Then I replaced the tranny oil with a acdelco GM synchromesh friction modified.
The old oil came out dark black! (Probably something related to the carbon synchros?)
Anyways, the tranny shifts like butter now, gears comes in really smooth, even in really high engine revs. This fluid is a magic.

So thanks everyone for the help and the information shared here.
 
1 - 13 of 13 Posts
Top