Tuesday, August 05, 2014 - 06:30 pm, by: David Sun(Shiny1)
I am about to rip my hair out! My 31 with a w58 conversion is not shifting properly at all! The clutch doesn't seem to disengage properly. Here are the symptoms:
1. Clutch in all the way - most times hard to get into gear (including reverse) 2. Once the car is moving, getting into gear isn't difficult, but it is still noticeably terrible. 3. Sometimes it is so bad that I have to forcefully stick it into 2nd gear and leave the pedal down. The car sounds like it will almost stall if I move it anymore. 4. Gearbox has been recently replaced with MT90.
Car slots into gears fine when it's turned off. Haven't bled anything yet, or adjusted anything yet. I took it to a mechanic and he said it was hard to adjust the clutch pedal/rod (?) because of the conversion. I don't know what to do. It's almost undrivable.
Tuesday, August 05, 2014 - 08:55 pm, by: Scott Vim(1uz1jz)
Sounds like the clutch isn't fully disengaged. I had this issue on a 1uz w58. Can't remember how it was fixed exactly but I think the clutch point needs adjusting. You will notice that when you are on a flat if you jam it into first the car will inch forward slightly. This is the clutch being engaged very slightly. It will wear the out of your clutch if left like this for too long.
Tuesday, August 05, 2014 - 09:59 pm, by: Robert Day(Lexsmaz)
As Scott said the clutch isn't disengaging, so its either the fault of the clutch or its not being disengaged properly due to air in the system or adjustment at the master cylinder .. Does the pedal feel firm the whole way or is there a soft bit of the pedal at the start of the travel ?
Is this a new conversion or has it been in the car a while & just the gearbox changed ..
Tuesday, August 05, 2014 - 10:57 pm, by: David Sun(Shiny1)
Conversion was done a long time ago. Unsure of the age of the clutch. It seems to have become worse over the last 2 months (I've only had it for 3 months). There doesn't seem to be any free play in the clutch pedal. I don't know how to adjust the rod. Are there any tutorials on here? I've done a clutch adjustment in a previous car, but it didn't really help much. I'm hoping a bleed (don't know how to do it) will help, and I really hope I don't have to resort to buying a new slave/master cylinder! Or worse... a clutch.
Tuesday, August 05, 2014 - 11:22 pm, by: Robert Day(Lexsmaz)
When you put your foot to the floor & engage first gear ( eventually ) where does the clutch start to take up & basically bog down the motor, I know you said it sounds like it want to stall, but you need to SLOWLY lift your foot off the clutch & see when the engine starts to really load up & keep lifting your foot very slowly till the car stalls & make note where that is in relation to how far off the floor the clutch pedal is ..( keep your other foot on the brake whilst doing this so the car doesn't actually move ) ..
The reason for the above test is to try & evaluate as to wether its the clutch or bleeding etc, if your foot is still very close to the floor when the engine stalls, it sounds like most probably air in the system etc, if you have to lift your foot a fair way from the floor before the engine stalls, it sounds like the clutch is at fault & possibly has a faulty / broken pressure plate diaphragm etc ..
Wednesday, August 06, 2014 - 05:57 pm, by: Shane Haverkamp(Havabeer)
bleeding clutch is easy, but will be a 2 person job (its exactly the same as bleeding brakes)
jack the car up the master cylinder is on the passenger side of the car on the gear box you'll see a little "nipple" on the end of the master cylinder (its like a little pointy thing with flats on it for a spanner) have a mate step on the clutch, and hold it in undo the nipple half a turn or more and you should hear some air come out quickly close the nipple have old mate take foot off the clutch have old mate push back on the pedal Open the nipple let air/fluid out close nipple foot off clutch keep going till you get a nice stream of fluid coming out when you crack the nipple
Thursday, August 07, 2014 - 06:18 pm, by: David Sun(Shiny1)
Thanks Scott, Rob and Shane. I have high hopes for this, and I will try out a bleed this weekend with a mate. After this, I just have to figure out what is causing my atrocious 5km/L fuel economy! (Less than 10 minute trips)
Saturday, August 09, 2014 - 03:38 pm, by: David Sun(Shiny1)
Guys I'm having difficulty locating this master cylinder:
jack the car up the master cylinder is on the passenger side of the car on the gear box you'll see a little "nipple" on the end of the master cylinder (its like a little pointy thing with flats on it for a spanner) have a mate step on the clutch, and hold it in undo the nipple half a turn or more and you should hear some air come out quickly close the nipple have old mate take foot off the clutch have old mate push back on the pedal Open the nipple let air/fluid out close nipple foot off clutch keep going till you get a nice stream of fluid coming out when you crack the nipple
I can't find it when I jack the car up. Where is the nipple? I'm pretty noob at this.
Also, I'm not sure if adjusting the clutch rod at the pedal will do anything. Here is a picture. Should I shorten it, or make it longer?
Saturday, August 09, 2014 - 04:04 pm, by: David Sun(Shiny1)
Found it. Now I tried to bleed it. I didn't hear any air come out, but a few droplets of fluid came out. I got my mate to press down all the way two or three times, then one last stomp and hold. Twist valve with spanner and let some droplets out. I repeated this 3 times. I don't know if that did anything (I'm still in the process).
Shane, what do you reckon about the clutch rod near the pedal?
Saturday, August 09, 2014 - 04:37 pm, by: Robert Day(Lexsmaz)
You should be getting a lot more fluid out than just a few drops, it should give a short squirt when you have someone holding the clutch pedal down when you crack the bleeder open .. get your mate to leave his foot OFF the pedal & you will probably have to undo the nipple completely & take it out & check to make sure its not blocked, there is a hole in the end that the fluid comes out & on the other end there is a small hole on the side up from the tip area ( blow through with compressed air or something to make sure its all clear ) you can even run some fine wire down the guts to be sure ..
Also don't worry about adjusting the pushrod yet till you have bled it properly, basically do one thing at a time ..
Saturday, August 09, 2014 - 08:26 pm, by: Peter Williams(Skeeta)
Don't forget to top up the master cylinder with fluid after you bleed the slave cylinder. Make sure the master cylinder has fluid in it before you start the bleed process.
Wednesday, August 27, 2014 - 04:07 pm, by: David Sun(Shiny1)
It's worse than I originally thought. The clutch fork is broken due to, what the mechanic believes, the heavy duty pressure plate. I need to source a new one and he recommended that I get a whole new clutch kit that is not standard duty to avoid this in the future.
Here are some pics to show you. I hope someone will be able to identify what kind of clutch fork I need. Spec: 1uz engine, w58 gearbox, CRS custom bellhousing.
If I am not mistaken, Neil Griffiths did the manual conversion, so I think I may have to ask him for advice on the clutch fork.
Hi David, That is the pressed metal one from W58. ( JZA80 Supra ) There are only 2 you can get for that trans. Pressed metal and Cast Iron. ( Cant use cast where pressed was ) That arm has been under a lot of stress. Heavy pressure plate should not put that much stress on it.
Wednesday, August 27, 2014 - 05:55 pm, by: Robert Day(Lexsmaz)
Wow that's certainly broken !! how heavy was the clutch to operate, probably not recently as its been cracking / causing a issue for a while but more so some months or years ago depending on how long you have had the car ..
I would also be looking closely at the ball shaped head on the clutch fork pivot inside the bell housing as it could be shaped poorly, which could put undue load on the fork & possibly cause the issue too ..
Wednesday, August 27, 2014 - 09:34 pm, by: David Sun(Shiny1)
Robert, is this what you're talking about?
(From the OCAU forums) does the thrust bearing slide nicely on the... bit it slides on? ----------------------------- if the thrust bearing is binding on the slide it will increase the force required to operate the clutch, if the fork pivot is crappy it could have worn through the fork. "heavy duty" pressure plates don't usually have amazingly high amounts of extra clamping force.
however plenty of people have put actual racing clutches/PPs in these gearboxes which do have much higher clamping force, have a hunt around and see if you can find similar failures, i wouldn't put a standard clutch back in unless your current one is toast and a standard one is a lot cheaper. What engine is the clutch and pressure plate from/for?
Wednesday, August 27, 2014 - 11:00 pm, by: Robert Day(Lexsmaz)
Hi David, all those items you have listed in red are relevant & the bit I was referring to was where they talk about "if the fork pivot is crappy it could have worn through the fork" the pivot that we are both talking about is the part that has actually poked through the fork you put a photo up of ..
Can you take some photos of that part & put it up too ..
As asked how heavy was the clutch to operate ?? as if it wasn't overly heavy to operate I wouldn't be looking at throwing a New clutch in it yet & also as has been mentioned check to see how freely the clutch thrust race slides on the input sleeve as that can make the clutch feel heavy too, so other things that are mentioned are more than likely the cause ?? & also lack of grease on the pivot ball certainly doesn't help matters & is it a OEM clutch fork or some aftermarket one ??
Just to finish off, clutch fork failures are generally fairly rare & I don't think I have ever seen one do that as far as poking through the pivot point ..
Wednesday, August 27, 2014 - 11:43 pm, by: David Sun(Shiny1)
Thanks for your reply, Robert. Unfortunately I can't take any photos of the car as it's in the workshop and I have work, so I couldn't tell you. I'm not knowledgeable enough anyway to answer those questions.
The clutch was heavy but I don't know if that was because of the problem we have here. I'll ask the mechanic what he thinks.
To answer your question, the fork is a standard JZA80 one, pressed metal.
Sunday, December 27, 2015 - 01:41 am, by: Ryan Owens(Ryano085)
DAVID Make sure you are using a big enough Master cylinder like really big one..
Was it not engaging from the word go or is it intermittent.
I used the wrong one at first and then put a 5/8 cylinder (I think) one from a hilux anyway
I would appreciate a little help myself What did you do as regards speed sensors I have the speed sensor 3 pin plug plugged in but I get a bong and goes in to limp mode I unplugged this and I get limp mode after it heats up