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IS200 J160 gearbox issue

12K views 30 replies 6 participants last post by  MEMAC 
#1 ·
Hi guys,

Hope you're all well!

Please bare with me as this is my first forum post!

I'm having an issue with my gearbox and wondering if someone could help.

After about 40 mins of normal driving gear changes become difficult sometimes so difficult i can't even get into first or reverse without rolling!

I have a 1G-FE engine with a 1GGTE single mass flywheel mated to a 3SGTE clutch. Clutch engagement is fine and all gear changes are smooth until the box gets a bit warm. The only required modification for this set-up to work was a longer slave cylinder rod to be installed.

I can feel the heat in the shifter shaft and gear knob itself it's not too hot to touch but there is defiantly some heat there!

I also have a Chinese Ali express short shifter installed which has always been fine.

I have also changed the gearbox oil which hasn't made much of an improvement. i have recently purchased some "red line" oil which is meant to be better.

I'm not too sure if maybe my slave cylinder rod needs to be longer or if my gearbox is leaking oil (I can't see any oil leaks) or if my box is dying.

If someone with able to advise me on some troubleshooting steps that would be massively appreciated!

My plans on troubleshooting is to replace the shifter with the OEM one and also change my oil to the red line one.

The car is a 2000 plate IS200 Sport with 75k miles on the clock.

Thanks a lot for reading!

Sean
 
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#2 ·
Sounds to me like the clutch isn't set right, on cars i've had when the clutch is knackered it might feel ok but not quite disengaging properly it wont go into gear very well. With the gearbox warming up something might be expanding and making the issue worse. Could be the pressure plate isnt pulling away far enough or the bearing isnt moving far enough, might need a longer rod or maybe the step it sits on in the flywheel isn't set right.

Why did you use those flywheel and clutch and not just a Exedy or other brand single mass for the IS200?
 
#3 ·
Thanks for the reply! It seems odd how something could already be faulty and i haven't even had this flywheel/clutch installed for a year and it was perfect at first for a month or two.

I have ready installed a longer slave rod.

Also the reason for the set-up is because i could not find any other flywheel that would fit a larger clutch disk to withstand more BHP. as the plan was to turbo the car, therefore i needed a clutch that can take 300 BHP all day long. The stock 1G-FE clutch wouldn't be able to cope with this power all day everyday.

Thanks
 
#4 ·
Im not 100% on that without actually seeing and driving it so i could be wrong, but its what it sounds like to me. ;)

Unfortunately you will be pushing the limits of the 1GFE and the J160 if you try and increase the power significantly. The 1GFE isnt made to handle boost without significant mods, unlike the 1J/2J engines. There is a supercharger kit around for it but it is a low boost setup, so realistically i doubt you are going to get that high. Same with the J160, it can handle some boost ok, but most of the Altezza RS200 crew over this side start having trouble with the J160 when they start boosting too high (same stock trans as the IS200). It will run low boost ok, and the S2000 apparently runs the same trans so it can handle RPM, i believe its just the torque the turbos produce can overpower it eventually. A lot will depend how you drive it though, same as with any trans. :)
 
#5 ·
I've spoken to a few people and the potential cause my be my clutch fluid. as its dot 4, the fluid may be getting too warm and "boiling" the plan is to completely bleed the system and put some dot 5.1 which has a higher boiling point which will hopefully solve my issue. As the issue only occurs once warm.

Also the 1G-FE can take 10 psi somewhat safely and a few have pushed 12/13 PSI on stock internal which will easily produce over 300 BHP but is very likely to blow the engine. as i have have seen dyno prints of 8 PSI producing 270 BHP.

Also the J160 is a fairly strong box! they are in Mazda RX8's, Honda S2000's as you said and Nissan S15's! and they are now being used for manual conversions for 1JZ/2JZ cars.

But If my clutch fluid is the issue I'll be sure to update the forum so others can see for future reference!
 
#6 ·
Swap in the Redline fluid and get back to us, it's the only MTL fluid I use for a reason. It also sounds like the clutch fluid should be replaced. Do you have a stock clutch dampener on those cars? I know the stock IS300 does, and removing it makes a huge difference in lack of delay/shifting.
 
#18 ·
i still think it sounds like the rod isnt long enough, or the step in the flywheel wasnt deep enough, or the pressure plate has relaxed or dropped a spring or 2 so not getting the movement. could also be leaking master or slave cylinder seals. As the plates wear it will highlight any weaknesses in the setup. Changing the fluid probably gave it just enough to fix it a little until everything settles back into place.

If it has enough fluid in it the box will be fine heat wise, they all get hot so unless you are racing it so everything is under extreme force constantly it wont need cooling, otherwise all the other cars using the same box would be having similar issues.
 
#20 ·
i still think it sounds like the rod isnt long enough, or the step in the flywheel wasnt deep enough, or the pressure plate has relaxed or dropped a spring or 2 so not getting the movement. could also be leaking master or slave cylinder seals. As the plates wear it will highlight any weaknesses in the setup. Changing the fluid probably gave it just enough to fix it a little until everything settles back into place.

If it has enough fluid in it the box will be fine heat wise, they all get hot so unless you are racing it so everything is under extreme force constantly it wont need cooling, otherwise all the other cars using the same box would be having similar issues.
That is my thought. There is no leak in any cylinder as the fluid doesn't drop at all.

I will have to see if i can get an adjustable rod and try again. Such a shame there is no inspection hole for these cars!
 
#25 ·
So a little update for any followers in the future, if you have a short shifter make sure you remove it! as it appears it was the short shifter all along that has caused my issue. Once it was removed and OEM shifter was re-installed everything seems to be ok. although it's all a bit floppy and flappy! but better than losing gears
 
#29 ·
The difference between J160 G and J160 S is the bellhousing. The J160 G will bolt up to the std block pattern for those Toyota engines that accepted the W series gearboxes, this included the T series and G series where the starter motor is on the RHS looking from the front. The 3S engine has the starter on the LHS, so you would have to swap over the bellhousing. If you wish to continue using a J160 for high torque output you are strongly advised to have the counter shaft modified to overcome the 4th gear failure associated with the split thrust washer or "C" clip. https://www.neatgearboxes.com.au/ here in South Australia are known for their great work in doing this. Hope this helps Malcolm
 
#31 ·
May I suggest the basic setup test we do on the rally car to test the clutch throw out is set OK, find a slope or hill with a clear run, turn off engine, engage 1st gear, brake off, car should hold on an off engine, now depress the clutch pedal until the car starts to roll forward, this is the point of release which I expect to be about a third of travel to the floor, on a gradual slope you can also try the initial grab point by having in gear, engine off but clutch down and on the brake, release brake and let car start to roll, come off clutch pedal and you should feel it start to pull up the car at about one third of the pedal travel off the floor, this is the range of engagement. Outside of this range I look for linkage ratios, master / slave cylinder ratios, push rod lengths and settings. Our standard practice after each event is to change fluid, on brakes it is even change between practice / qualifying and main race. This is just a start point on checking that the clutch pressure plate is in the range of the throw out system (normally a pivoted lever with push rod activation), hope this might help, Malcolm
 
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