car only makes a weird nosie coming out of 1st gear, any ideas? 93 Prelude Si 5 speed manual

holden j caufield

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Dec 30, 1999
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It makes a strange almost grinding noise but not quite only when I go from stationary to moving in 1st gear. Otherwise it drives fine.

EDIT: Also in the first 3 min or so it takes a bit more effort/force to shift it to 1st gear? Sounds like synchros?
 

Zenmervolt

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Oct 22, 2000
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Clutch isn't disengaging completely. First gear typically has a much weaker synchro than the other gears because it is very, very rare for a person to go into first when the car is in motion. If the clutch is dragging even slightly, it will show up initially in 1st gear with either grinding noises or difficulty engaging the gear.

Have you clutch checked to see if it is disengaging fully. (There is typically an inspection hole for this and the procedure should be described in your shop manuals.) If it's not, replace the clutch master and slave cylinders (always better to replace them as a pair since they cycle together and if one is worn out, the other is likely to be close to wearing out, plus, it's just easier to do them both rather than dis-assemble everything a second time) after checking to see that it's not something simple like just needing to bleed the clutch hydraulics. Bleeding procedures for your car will also be listed in the shop manual.

ZV
 

jagec

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Apr 30, 2004
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My Celica didn't even HAVE a synchro on first gear...how lame is that :roll:
 

holden j caufield

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Dec 30, 1999
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93 Prelude Si 5 speed Manual

Thx for the info. I've got a busy 8 days a head of me and can't have my car sitting at the shop for a day. How pertinent is it to have it done right away if it is the clutch or synchros?
 

Zenmervolt

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Oct 22, 2000
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Originally posted by: jagec
My Celica didn't even HAVE a synchro on first gear...how lame is that :roll:
Well, most cars didn't until very recently. It shouldn't ever be an issue for normal driving since there's absolutely no need to go into first gear with the car moving.

And if you're running around an autocross course or something and do need first gear, you can just double-clutch. It's not as though that's a difficult skill.

ZV
 

jagec

Lifer
Apr 30, 2004
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Originally posted by: Zenmervolt
It shouldn't ever be an issue for normal driving since there's absolutely no need to go into first gear with the car moving.

You must not drive the same I-5 that I do...there were PLENTY of times that traffic was still moving, but slower than idle in Second.
 

Zenmervolt

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Oct 22, 2000
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Originally posted by: holden j caufield
93 Prelude Si 5 speed Manual

Thx for the info. I've got a busy 8 days a head of me and can't have my car sitting at the shop for a day. How pertinent is it to have it done right away if it is the clutch or synchros?
You'll wear the dog-teeth off the mechanism that engages first gear and lose the gear completely if you grind it very often.

You'll also dump the metal shavings that come off into the gear oil, which will cause wear on the other gears in your transmission.

Finally, since your car is FWD, the differential is in the same casting as the transmission, meaning that those metal shavings will wear the differential gears too.

If you can keep it from grinding, you'll be fine. If not, you'll definitely accenerate the wear on your transmission and differential.

Make sure that the gear oil in the transmission is flushed and re-filled after you get the problem fixed too, otherwise all those little metal shavings will still be in there, wearing your transmission.

ZV
 

Zenmervolt

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Oct 22, 2000
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Originally posted by: jagec
Originally posted by: Zenmervolt
It shouldn't ever be an issue for normal driving since there's absolutely no need to go into first gear with the car moving.
You must not drive the same I-5 that I do...there were PLENTY of times that traffic was still moving, but slower than idle in Second.
Then just double-clutch. It's not like it's hard.

And right now, I don't drive the same I-5. I live in Federal Way and commute into Tacoma. Reverse of all you suckers. :p

ZV
 

holden j caufield

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Dec 30, 1999
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thx. BTW the noise isn't the grinding that you get when as when you make a mistake in shifting gears. It's a different noise altogether that's hard to describe. And oh yes I know the I-5 all to well.
 

holden j caufield

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oh yes forgot that in the first 3 min or so it's takes a bit more force to me to shift from neutral to 1st, seems stuckish. After the car is warm it's easy to shift to first.
 

Zenmervolt

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Oct 22, 2000
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Originally posted by: holden j caufield
oh yes forgot that in the first 3 min or so it's takes a bit more force to me to shift from neutral to 1st, seems stuckish. After the car is warm it's easy to shift to first.
How cold is it?

When the gear oil is cold and thick on a winter morning it's much more difficult to shift until the transmission has been spinning for a while and the gear oil has warmed up and thinned out a bit allowing the synchros to work better. I've switched to Mobil 1 gear oil and it has helped a lot in the winters for the gearbox in my 944. A marginal synchro and a lightly dragging clutch could definitely be causing what you describe, because a marginal synchro will need the gear oil to be warmer before it will work effectively.

ZV
 

Vic

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Jun 12, 2001
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Zenmervolt is still right, if I'm reading you right. You're saying that you hear a strange, almost grinding, noise as you let the clutch out to start moving in 1st gear from a dead stop. Sounds to me like the clutch disc is failing.
Sticky shifting with a manual trans for the first few minutes after a cold start is normal. The gears operate in a viscous oil that is temperature sensitive (just like your motor, which is why you are supposed to drive gently until it warms up).
 

holden j caufield

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thx again for the info guys. Roughly how much ~$ is this going to cost. I'm just wondering ballpark so I don't get overcharged. Also is the clutch anywhere near the timing belt and water pump because I figure as long as they are in that part of the car they might as well replace those too.
 

Zenmervolt

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Oct 22, 2000
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Originally posted by: Vic
Zenmervolt is still right, if I'm reading you right. You're saying that you hear a strange, almost grinding, noise as you let the clutch out to start moving in 1st gear from a dead stop. Sounds to me like the clutch disc is failing.
Sticky shifting with a manual trans for the first few minutes after a cold start is normal. The gears operate in a viscous oil that is temperature sensitive (just like your motor, which is why you are supposed to drive gently until it warms up).
Alternately, you can let the car warm up while stationary with the transmission in neutral and the clutch engaged since the input shaft and gears will still spin, causing the gear oil to warm up.

Of course, that can take a couple minutes and it's generally better to just drive carefully because you'll waste a lot of gasoline waiting for the transmission to warm up.

Vic, it's always nice to have someone else who knows about cars around. I know that Roger kinda came back, but it's still not the same and I'm glad there are still mechanics around. :)

ZV
 

Zenmervolt

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Oct 22, 2000
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Originally posted by: holden j caufield
thx again for the info guys. Roughly how much ~$ is this going to cost. I'm just wondering ballpark so I don't get overcharged.
Too many possibilities.

It could just be an air bubble in the clutch hydraulics, which would only be maybe $100 to bleed and re-fill.

Could be a failing clutch that needs replacement, which would be between $600 and $2,000 depending on how much labor it takes for a clutch job on your car. (For your car, I'm thinking much, much, much closer to $600.)

Could be th synchros, in which case you'd pretty much need a transmission rebuild/replacement. No clue on the prices there.

ZV