Judder in reverse.

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Dixie6789
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Judder in reverse.

Post by Dixie6789 »

Just rebuilt the T5. All good in all forward gears. New clutch and plate. Lightened flywheel. New TR8 rear rubber mount,. New sort prop.
When I drive in reverse I get a judder, I appreciate not very discriptive, but has anyone had this before?

Thanks Mark.


Mark

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ChrisJC
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Re: Judder in reverse.

Post by ChrisJC »

Are all the engine mounts secure? going in reverse will load them oppositely to normal.

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DaveEFI
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Re: Judder in reverse.

Post by DaveEFI »

Is this when moving off, so possibly the clutch, or when it is fully home?
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DEVONMAN
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Re: Judder in reverse.

Post by DEVONMAN »

Did you treat the new clutch gently for 100 miles? This beds the disc in and removes any high spots and gives a firmer even pressure all over the plate. If you work the clutch hard for the first few miles (tempting I know) then the high spots get scorched and shine up.
1950 A40 Devon Hotrod with 5.0 twin turbo RV8.
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!


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Dixie6789
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Re: Judder in reverse.

Post by Dixie6789 »

It's only when I start off. Once engaged all good.
Clutch slipped a little at the beginning when in 4th gear, now I have 150 miles it has firmed up and doesn't slip.
Also have a judder when pulling away in 1st, not all the time, but probably 50%.
I wonder if needs more bedding in?
Plus side, the box is lovely.
Mark

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Re: Judder in reverse.

Post by DaveEFI »

A brand new clutch which slips in any gear - even if not bedded in - doesn't sound good to me.
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DEVONMAN
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Re: Judder in reverse.

Post by DEVONMAN »

I agree that any slip is not good for a new installation. Until bedded in all the high spots are the ONLY points transmitting power and they will scorch and shine up if slip happens. The plate (if not a match pair) may be slightly too thick for the cover and this will give slightly less diaphragm pressure until the plate thins and wears in. Pedal force gets heavier as the clutch wears. If the plate is a miss match and initially too thin, then if slipping occurs after bedding in, slipping will only get worse as it wears.

Some clutch plate materials do tend to judder and are more suitable for track use etc.

The judder could be a quirk of the tilted mustang rear gearbox mount but if it's new and firm then probably not.

Hopefully, you haven't got a bellhousing alignment problem.
1950 A40 Devon Hotrod with 5.0 twin turbo RV8.
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!


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Dixie6789
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Re: Judder in reverse.

Post by Dixie6789 »

Only slipped in 4th when I accelarated very hard, I could hear the revs rising. In 1st, 2nd and 3rd it was fine. Now it’s fine apart from a slight judder.

The clutch and pressure plate are from different sources.

The friction plate is about 7.5mm thick, same as the one that came out.

The input shaft went in easily, I actually used it to align the plate before Installed in the box.

A few more miles needed to settle things down. May get a new clutch and plate later if things don’t improve.
Mark

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Re: Judder in reverse.

Post by DEVONMAN »

The fact that it went together easily is not really a check on the bellhousing alignment. Even 10 thou out would mean the plate is picking up on one side until it gets squashed evenly against the flywheel by the pressure plate.
1950 A40 Devon Hotrod with 5.0 twin turbo RV8.
EDIS8 wasted spark, Holley Injection.
Been as far as the Moon and back in 57 years of driving. Same Car, 5 engine upgrades !!!


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Dixie6789
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Re: Judder in reverse.

Post by Dixie6789 »

I know it's been a while. But taken the box out to put an over drive 5th in. Now 0.71.

While apart I dialed in the bell housing, it was 0.020 out North/South and 0.025" East/West. Now spot on thanks to some 0.014" offset pins.

Its been a steep learning curve, thanks to YouTube.

Mark.
Mark

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