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Discussion Starter #1
Hi Guys,

I had a three hour drive in my 2L 105 yesterday, the longest drive yet, and after about 2.5 hours I noticed that I was not able to select first or Reverse without feeling the gearteeth grinding. I was still able to select other gears.

Both these gears had been ok to select before albeit the syncro's we showing signs of wear, so I was wondering if it may be someting to do with the clutch or is it typical of syncros suddenly failing?

regards
Tim
 

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71 Berlina 74 GTV 17 Giulia Q4
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maybe one but 1st isn't really syncroed in the true sense of the word and reverse is just two gears coming together, no synco at all there and they are also controled by two different rods/forks so odds of two of the exact same failures of two different gears at the same time is very odd. no funny feel in 5th or 2nd? Can you select those gears when the car is stopped and engine off?
 

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Does the clutch start to engage at it's 'normal' height above the floor? If it is engaging closer to the floor than usual, suspect a hydraulics problem.

Another thought is that since the problem occurs after a long drive (when the gearbox oil is hot), it may be the oil itself simply thinning out (less friction from thin oil will allow the gears to spin longer after the clutch is depressed). What oil are you using and when was it last changed?
 

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71 Berlina 74 GTV 17 Giulia Q4
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10-4 on that, it's usually the simple stuff unless you hear loud bangs.
 

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Tim,

it's possible that the little bolt that holds the shift fork on the internal rod has fractured. This means you can move the gear lever, the rod moves, but the fork doesn't. Ask me how I know...

Hi Guys,

I had a three hour drive in my 2L 105 yesterday, the longest drive yet, and after about 2.5 hours I noticed that I was not able to select first or Reverse without feeling the gearteeth grinding. I was still able to select other gears.

Both these gears had been ok to select before albeit the syncro's we showing signs of wear, so I was wondering if it may be someting to do with the clutch or is it typical of syncros suddenly failing?

regards
Tim
 

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71 Berlina 74 GTV 17 Giulia Q4
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That would be two bolts breaking at the same time or comming loose. Although I suppose one could break and jam the other rod. Again does it shift into gear when stopped?
 

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Discussion Starter #7
Thanks for the suggestions guys.
Firstly the gearbox oils along with all other fluids were changed 1000km ago.
The gearbox has Penrite Hypoid 80W-90 oil and up to now seems to allow a smooth gearchange except when first cold when second seems to be alittle grindy until warm (due to a worn syncro)......even if I had a new syncro on 2nd I have heard this can still be an issue until warm.

I am begining to think it may be a hydraulic clutch problem because when the clutch is disengaged the gearbox gears should stop spinning in a short time. At the moment it feels as if they are still spinning at engine speed and will not slow down if I try to slow them down by slowly engaging the gear.

What has thrown me off is if the clutch is not properly disengaging then I should expect the same problem with gears 2, 3, 4 and 5.

I may change out the clutch fluid and re bleed as a first remedy in case the fuild is geting affected by a hot engine bay......not confident!

Cheers
Tim
 

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...if the clutch is not properly disengaging then I should expect the same problem with gears 2, 3, 4 and 5.
Not necessarily.
The reason is that 2, 3, 4 & 5 are syncronised from neutral; 1 & Rev are not.
There has to be at least some clutch disengagement otherwise 2, 3, 4 & 5 could not be selected with engine running and vehicle stopped.
 

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Definitely sounds like the clutch - it's not fully disengaging. I've had this problem. The 2-5 synchros can overcome the residual rotation, but there's none in 1st and rev, so it crunches.
 

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Press the clutch pedal and put it into 3rd, then quickly into 1st or reverse and see if it still grinds.
 

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It doesn't sound like the clutch to me. Sounds like the fully warmed tranny is allowing the partial / non-synchroed 1st/reverse to show their true colors. In road test articles from when new, these cars demonstrated grinding in said gears. If the clutch is engaging anywhere but at the floor, then I'm sure it's fine. The tip to bump 3rd should work.
 

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Seems to me your clutch is dragging just slightly. Not much as when the oil is cold the viscosity is enough to slow the spinning gears to a stop.
When you have been driving for 2 1/2 hours the oil is warm and of lower viscosity. The drag of the oil is now insufficient to slow the gears to a stop. The clutch drag is sufficiently minor that the synchos can overcome it in the other gears.
Would I be worried? Not unless it gets much worse. The trick of banging it into a synchonised gear to stop the spinning before selecting unsychronised first or reverse is an old one and a good one.
Nor would I be tempted to put in a heavier oil just so it can drag the gears to a stop. Extra viscosity means extra drag in the gearbox which means more power consumption. More power consumption means more heat build up which means higher temperatures in the gearbox. Higher temperatures means lower viscosity. Isn't that where we started?
 

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Discussion Starter #13
Thanks for all the suggestions guys, like most problems, it could be more than one problem I am encountering.....I suppose not uncommon for an old car!

I must admit that since I purchased the car 2 years ago I have at times needed to put the gear selector in 2nd or 3rd before engaging first when at the lights or reversing. But this trick did not seem to work for me during my long drive.

The clutch is engaging about half way but I did also notice that even though 2,3,4 and 5 was enagaged without grinding, it did feel alittle more stiff to enagage than normal.

It is interesting hans that you mentioned that even when new these gearboxes were not silky smooth in 1st and reverse. Does this mean when I eventually overhaul my gearbox (I am tempted to do it myself) if I put new syncros in 1st and reverse then it will still be alittle grindy??

regards
Tim
 

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According to other posts, reverse was never synchronized and 1st is semi-syncronized. I don't know if one can add full synchronizers to these gears, but anything is possible. Redline 75-90 NS oil helps quiet 1st and reverse. I still don't see how your issue (and some others') is clutch related. If the release arm traveles its spec distance and the engine can free rev, then the pressure plate is releasing the clutch disc.

My 2nd gear grinds on the up and downshift--even when double clutching--and I know my clutch is fully releasing. Problem is in the tranny.
 

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I have to say my money is on the clutch. Re adjust to obtain proper clearance and see if the problem diminishes. I suspect that it will. This is a cheap alternative!
 

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Discussion Starter #17
This weekend I changed the hydraulic fluid in the clutch system and did notice it was rather brown looking. I was surprised as I always like to change the brake/clutch fluid every 18m-2y. I am suspecting that the clutch master or slave cylinder will need replacing as it looked a bit like rust in the fluid. These items were not touched when I got the car a couple of years ago so may need replacing.

I also noticed that when trying to bleed the fluid, the clutch pedal did not willingly come back without a bit of light tapping, probably the seals wearing and rust in the cylinders?

After eventually getting the system bled, I drove the car to my vets hockey game and it seems to drive like it did before. However I did not get the gearbox as hot.

Will see whats happens.....thanks again

regards
Tim
 

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Tapping a gear before going into first is almost like breathing, I do third simply because it's right next door and although the same can be said of second I don't like to touch that synco ring unless I'm actually using it. I suppose the wear or in this case lack of wear on the 2nd gear is probably not measurable 3rd just seems more natural to me but then again that's just me:confused:
 
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