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Discussion Starter #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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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?
 

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Discussion Starter #3
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?
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
 

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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. :)
 

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Discussion Starter #5
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. :)
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!
 

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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.
 

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Discussion Starter #7
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.
Thanks for your reply.

I have some Redline gearbox oil to go in already so I'll get that sorted! I'm also changing the clutch fluid to some DOT 5.1.

There is no clutch dampener on the IS200 unlike the IS300 unfortunately.

Thanks
 

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Okay guys, so the DOT 5.1 fluid is in! the old fluid was black as anything. Also put in some redline gearbox oil.

My biting point has also raised half an inch/ inch so hopefully it's good news!
 

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Discussion Starter #16
Let's start from the beginning. Make a list of all the new parts you have done and what exactly it is doing.
So i have completely changed the clutch fluid from DOT 4 to DOT 5.1.
A longer slave cylinder rod has been installed
Gearbox oil has also been changed

I was debating on using some heat wrap but apparently it's not the best as it holds the heat for longer and can actually make things worse.

Thanks
 

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So i have completely changed the clutch fluid from DOT 4 to DOT 5.1.
A longer slave cylinder rod has been installed
Gearbox oil has also been changed

I was debating on using some heat wrap but apparently it's not the best as it holds the heat for longer and can actually make things worse.

Thanks
I do not think heat is the issue. Does the tranny whine any? Or vibrate when in use?
 

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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.
 

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Discussion Starter #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!
 
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