Should there be a gap between the engine and gearbox?

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RobFrost
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Should there be a gap between the engine and gearbox?

Post by RobFrost »

Got under the 911t for a few jobs today. There seems to be a gap between the engine and gearbox where I could insert a screwdriver a few mm. Is that normal or anything to be concerned about?

I would have expected these to be clamped flush together.Image

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1970 911T, Signal orange (Restoration thread)
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911hillclimber
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Re: Should there be a gap between the engine and gearbox?

Post by 911hillclimber »

Yes, metal to metal.
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RobFrost
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Re: Should there be a gap between the engine and gearbox?

Post by RobFrost »

911hillclimber wrote:Yes, metal to metal.
Is there any reason why I wouldn't just tighten up the bell housing bolts? Or any reason why it would have been left like that?

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1970 911T, Signal orange (Restoration thread)
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
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Nige
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Re: Should there be a gap between the engine and gearbox?

Post by Nige »

Tighten it up, but check the clutch action afterwards. Just wondering if it's have a miss match of clutch and flywheel in the past causing the gap?
911hillclimber
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Re: Should there be a gap between the engine and gearbox?

Post by 911hillclimber »

Agree, I would be very suspicious of that gap. Lots of crud in the gap, so wash it out with a good blast of clutch/brake cleaner rattle can then tighten. If it won't close the gap easily stop. something is interfering.
73T 911 Coupe, road/hillclimber 3.2L
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Re: Should there be a gap between the engine and gearbox?

Post by jwhillracer »

No - I wouldn't tighten that until you have taken it apart and cleaned both surfaces back to bare metal. There's too much chance of causing distortion or even cracking from tightening it with loads of cr@p in between.

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inaglasshouse
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Re: Should there be a gap between the engine and gearbox?

Post by inaglasshouse »

I'm with JW. The bell housing attachment points are not super strong - have quite often seen the casing broken in those places. Caution is required when tightening.
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Re: Should there be a gap between the engine and gearbox?

Post by BILLY BEAN »

inaglasshouse wrote:I'm with JW. The bell housing attachment points are not super strong - have quite often seen the casing broken in those places. Caution is required when tightening.
Totally agree.
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Re: Should there be a gap between the engine and gearbox?

Post by 911hillclimber »

Can't help thinking it is time to pull the whole drive train as you have quite a few 'issues' going on, it is an old car!
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
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