3rd gear / selector issue

[FNFAST VR4]

Whilst reassembling my gearbox, I had a lot of trouble getting the middle selector in. I cleaned up the slot it goes into, and the fork itself (not sure why it decided it was too big for the slot after it was apart for a while). And it went back together ok.

Now that the car is all reassembled etc, if I give it a bit of stick in second and go for third it won't go in first pop. It takes a couple of goes to get into gear.

My first thoughts are that its either the synchro or the selector still playing up.

I am not sure about the synchro, because wouldn't it be graunching together if that was the problem? It just feels weird, like you can feel things whirring thru the lever.

Which leads me to think its the selector fork/rod whatever its called.

My question is, why has it decided to be a pain in the ass? It was apart for a while, but the other two went in fine? Which made me wonder if it may be bent or something?

Anyone have any thoughts?

[Subaru ETA]

i havent had a vr4 box apart, but are the detent all in the right place?

[FNFAST VR4]

i havent had a vr4 box apart, but are the detent all in the right place?

Are the what in the same place? I've had it apart twice now /Grrr

I haven't removed the fork off the shaft its on, so should all still be the same as far as I can tell. Not sure whats changed!

[Kenneth]

if its going into gear at all, the selector fork must be ok.

Sounds like a synchro, are you using the correct gearbox oil? Isn't that was happens if you use GL-5 oil in the gearboxes? You might want to chat with Don (amsoil) to see if it sounds like an oil problem.

[FNFAST VR4]

if its going into gear at all, the selector fork must be ok.

Sounds like a synchro, are you using the correct gearbox oil? Isn't that was happens if you use GL-5 oil in the gearboxes? You might want to chat with Don (amsoil) to see if it sounds like an oil problem.

I will try changing the oil. This morning on the way to work it had trouble with both 3rd and 4th. So maybe that is the problem. Which grade oil should be in it?

[Kenneth]

I will try changing the oil. This morning on the way to work it had trouble with both 3rd and 4th. So maybe that is the problem. Which grade oil should be in it?

um, not entirely sure on the oil grade, but I believe it has to be GL-4 ONLY (most say conforms to GL-4 and GL-5, which means its a GL-5 oil)

I would have a chat to amsoil, he is very helpful and is likely to put you on the right track.

I have an Amsoil oil in my gearbox at the moment, the grade is a little thick when cold I believe, and I get the odd difficulty getting into the low gears sometimes (requires a good shove), but its nothing major and goes away when warm.

[FNFAST VR4]

um, not entirely sure on the oil grade, but I believe it has to be GL-4 ONLY (most say conforms to GL-4 and GL-5, which means its a GL-5 oil)

I would have a chat to amsoil, he is very helpful and is likely to put you on the right track.

I have an Amsoil oil in my gearbox at the moment, the grade is a little thick when cold I believe, and I get the odd difficulty getting into the low gears sometimes (requires a good shove), but its nothing major and goes away when warm.

I will change the oil. Things are a bit tight right now as I'm moving out of my flat in two weeks time, and am so hanging out for getting my bond back!

[FNFAST VR4]

Right, changed the oil and nothing was different... went for a decent drive in it, and found an empty industrial area to give it some stick. Still no improvement.

Got ****ty with it and shoved it hard into third, and now its sweet as... ODD!

Hopefully tomorrow it stays sweet hehe. Will see what happens I guess.

[bradc]

it may have just needed to go into 3rd properly for the first time to move it all around or maybe get the synchro's going right :) Just keep an eye on it, and make plenty of gear changes I guess to test it out :)

[amsoil]

Sounds like a sticking (pretty much locked up) detent to me, fingers crossed that it was just a bit of crap and the problem wont re occur. Guess a 'marked' spline on the main shaft could cause this but you would have to have had the shaft out and dropped it to do this. Fingers crossed.

[FNFAST VR4]

Sounds like a sticking (pretty much locked up) detent to me, fingers crossed that it was just a bit of crap and the problem wont re occur. Guess a 'marked' spline on the main shaft could cause this but you would have to have had the shaft out and dropped it to do this. Fingers crossed.

What's a detent?

I've had the whole thing in pieces so thinking maybe it could have been knocked over or whatever while the pieces were all over the garage floor.

It would go into third before, just required a little coaxing, it was like something wasn't lined up right, but sometimes it would still go in fine... Will definitely keep an eye on it!

[amsoil]

All syncro boxes I have dealt with have 3 or 4 little spings with ball bearings on top which press a tiny toothed plate (detent) to the underside of the syncro hub to positively locate it in the correct position. The brass syncro cone locates on the syncro hub which bites and locks onto it matching gear speeds and enabling gear selection. These itlle parts do not suffer damage or grit /foriegn poarticles very well as it stops their smooth movement. If you pull a hub apart for the 1st time you will know it as after you have stopped swearing you will be looking all around the room for the little components that have fired out all over the place. They can be a pig to find and then get back in. You can have a detent slightly out of position which means that it will not be able to move out of the way allowing the syncro hub to move. If it is this bit out of position then knocking it back by force and fortune will have reset it and you wont have the problem again. If its just crap / grit it will be quickly dispersed in use. If its damaged / marked splines then it will take a l,ong time only slowly improving.
Then again it could be something else.
Hope this assists.

[FNFAST VR4]

It does. Thanks for that man. I've got my fingers firmly crossed.

[Subaru ETA]

It does. Thanks for that man. I've got my fingers firmly crossed.

whoops sorry bro forgot about this thread re the detents but its be answered so im not needed...but yeah they lock the syncro and stop two gears being selected...and yes they fire out in all direstions coz of the spring.....dont ask me how i know! :p