Jump to content
SAU Community

R33 Gearbox Wont Change Under High Rpm No Crunch?

xm4tr1x
 Share

Recommended Posts

xm4tr1x Enthusiast

xm4tr1x

Posted
Posted

Hi guys, I've had this problem for a while now and its really bugging me, mechanics are telling me its syncros, others say clutch.

I'd like to hear what the experts on SAU have to say about it, before you ask I've searched threads and couldn't find anything that describes what I'm experiencing.

OK so once i start i let it warm up a few min before engaging gear, for the first 3 min of driving its great gears change with ease no problems, as it gets warmer it gets harder and harder to change gears, more so under higher RPM, the gear stick just doesn't want to go into gear, it feels like im hitting a wall! i feel like i can break it trying to do so. lol. I've tried wriggling it into gear, double clutching, nothing works i just have to wait for the RPM to drop to <3k rpm before it decides to go into gear, there's no crunching or grinding. I've tried adjusting the friction point on the pedal.still nothing. What the hell? stationary it goes into every gear. low RPM it goes in to every gear. even down gearing at high rpm wont work.

What are your thoughts?

Much appreciated.

some details about the car:

r33 det series 2

110k

jim berry clutch

original gearbox

shimmed diff.

MrStabby Grand Master

MrStabby

Posted
Posted

Wont be clutch, because its fine cold and you've been playing with the friction point. (FWIW If the friction point is too low then the clutch might not be fully disengaging and that will make changing gears difficult).

Have you got newish, synthetic oil of the correct viscosity up to the fill mark? If not, i'd be starting there.

SiR_RB Grand Master

SiR_RB

Posted
Posted

I had an issue like this at the drags last month

Without a burnout no problems at all....after a burnout wouldn't go into 2nd, no grinding or anything just couldn't find home

Don't know what it is so I'm curious to see what ppl say

89CAL Grand Master

89CAL

Posted
Posted

OP: As with what some of the others have suggested, you need to list what oil you are using. To me it sounds like the oil you are using becomes to thin as it warms up. I would suggest changing oil if there is no problem while the gearbox is cold and then gets worse as it warms up

pol1on1 Mentor

pol1on1

Posted
Posted

Sounds like synchro 1st start at changing the oil it's the cheapest option and you can go higher in number if you think the internals are a bit worn out

Say the normal is 75W 90

A higher one is 85W 140

Do a flush so it nice and clean and not metal fragments in their and use a good brand like royal purple.

Tell us what you did to fix ?

pol1on1 Mentor

pol1on1

Posted
Posted (edited)

Also oil basics

The W stands for winter it's the viscosity when cool so 75 is thinner than 85 but you got no problem there because you have problems with the second number (viscosity when HOT) the 90 this could be old oil and losts it property's or the previous owner was using 140 then when you get service done it's back at 90 also worn internals will need thicker.

Hope it helps you.

Edited by pol1on1
jiffo Mentor

jiffo

Posted
Posted

As you've pretty well ruled out the clutch, I'm thinking it's a worn box.

The k's quoted may not be true so try a test and report back.

Drive the car in 2nd and hold the stick hard into gear. Accelerate/back off a few times and feel how much the stick moves against your hand.

Do this in 3rd, difficult trying 1st as the car accelerates too quickly but give it a try.

With a worn box, you get excess end float in the main shaft. You'll feel this through the stick as the shaft tries to move forwards/backwards due to the thrust from the helical gears.

You can reach a stage where the shaft moves too far and even though the synchro has worked, the result is tooth on tooth so you simply can't select the gear.

You may find selecting 2nd is a no-go and 3rd is OK but with a crunch.

(2nd has gone tooth-on-tooth while 3rd has moved too far away for correct synchronisation)

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Duncan
      V37 Suspension change

      By Duncan · Posted

      And finally, the front lower mount. It was doubly weird. Firstly, the lower mount is held in with a bracket that has 3 bolts (it also acts as the steering lock stop), and then a nut on the shock lower mount itself. So, remove the 3x 14mm head bolts , then the 17mm nut that holds the shock in. From there, you can't actually remove the shock from the lower mount bolt (took me a while to work that out....) Sadly I don't have a pic of the other side, but the swaybar mounts to the same bolt that holds the shock in. You need to push that swaybar mount/bolt back so the shock can be pulled out past the lower control arm.  In this pic you can see the bolt partly pushed back, but it had to go further than that to release the shock. Once the shock is out, putting the new one in is "reverse of disassembly". Put the top of the shock through at least one hole and put a nut on loosely to hold it in place. Put the lower end in place and push the swaybar mount / shock bolt back in place, then loosely attach the other 2 top nuts. Bolt the bracket back in place with the 14mm head bolts and finally put the nut onto the lower bolt. Done....you have new suspension on your v37!
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      And now to the front.  No pics of the 3 nuts holding the front struts on, they are easy to spot. Undo 2 and leave the closest one on loosely. Underneath we have to deal with the wiring again, but this time its worse because the plug is behind the guard liner. You'll have to decide how much of the guard liner to remove, I undid the lower liner's top, inside and lower clips, but didn't pull it full off the guard. Same issue undoing the plug as at the rear, you need to firmly push the release clip from below while equally firmly gripping the plug body and pulling it out of  the socket. I used my fancy electrical disconnect pliers to get in there There is also one clip for the wiring, unlike at the rear I could not get behind it so just had to lever it up and out.....not in great condition to re-use in future.
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      Onto the rear lower shock mount. It's worth starting with a decent degrease to remove 10+ years of road grime, and perhaps also spray a penetrating oil on the shock lower nut. Don't forget to include the shock wiring and plug in the clean.... Deal with the wiring first; you need to release 2 clips where the wiring goes into the bracket (use long nose pliers behind the bracket to compress the clip so you can reuse it), and the rubber mount slides out, then release the plug.  I found it very hard to unplug, from underneath you can compress the tab with a screwdriver or similar, and gently but firmly pull the plug out of the socket (regular pliers may help but don't put too much pressure on the plastic. The lower mount is straightforward, 17mm nut and you can pull the shock out. As I wasn't putting a standard shock back in, I gave the car side wiring socket a generous gob of dialectric grease to keep crap out in the future. Putting the new shock in is straightforward, feed it into at least 1 of the bolt holes at the top and reach around to put a nut on it to hold it up. Then put on the other 2 top nuts loosely and put the shock onto the lower mounting bolt (you may need to lift the hub a little if the new shock is shorter). Tighten the lower nut and 3 upper nuts and you are done. In my case the BC Racing shocks came assembled for the fronts, but the rears needed to re-use the factory strut tops. For that you need spring compressors to take the pressure off the top nut (they are compressed enough when the spring can move between the top and bottom spring seats. Then a 17mm ring spanner to undo the nut while using an 8mm open spanner to stop the shaft turning (or, if you are really lucky you might get it off with a rattle gun).
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      You will now be able to lift the parcel shelf trim enough to get to the shock cover bolts; if you need to full remove the parcel shelf trim for some reason you also remove the escutcheons around the rear seat release and you will have to unplug the high stop light wiring from the boot. Next up is removal of the bracket; 6 nuts and a bolt Good news, you've finally got to the strut top! Remove the dust cover and the 3 shock mount nuts (perhaps leave 1 on lightly for now....) Same on the other side, but easier now you've done it all before
    • Duncan
      V37 Suspension change

      By Duncan · Posted

      OK, so a bunch of trim needs to come off to get to the rear shock top mounts. Once the seat is out of the way, the plastic trim needs to come off. Remove 2 clips at the top then slide the trim towards the centre of the car to clear the lower clip Next you need to be able to lift the parcel shelf, which means you need to remove the mid dark trim around the door, and then the upper light trim above the parcel shelf. The mid trim has a clip in the middle to remove first, then lift the lowest trim off the top of the mid trim (unclips). At the top there is a hidden clip on the inner side to release first by pulling inwards, then the main clip releases by pulling the top towards the front of the car. The door seal comes off with the trim, just put them aside. The the lighter upper trim, this is easy to break to top clips so take it carefully. There is a hidden clip towards the bottom and another in the middle to release first by pulling inwards. Once they are out, there are 3 clips along the rear windscreen side of the panel that are hard to get under. This is what the rear of the panel looks like to assist:
×
×
  • Create New...