Primary case retaining screws...
- Thread starter Onder
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Normally, no.
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- Mar 7, 2019
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Mine had helicoil, and my father in law bought it new and I was the first to ever open it up.
Time Warp
.......back to the 70's.
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- Dec 3, 2012
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3 sets of 20M3S cases all the same (1.5D ?) Helicoil. (full depth to the inner wall)
Mk2a also Helicoil and no reason to believe the bottom end had been touched previously.
#
The factory must have got a bulk deal on the standard length coil as it is the same as the 750.
The 850 case could have got a 2D coil maybe longer with the thicker primary wall in that area.
If you are going to tap all the way for an insert, why not utilise that instead of half of it.
The 850 it seems has Helicoil there and at the engine case oil pipe junction, oil pump studs and 4 long cylinder cap screws.
Mk2a also Helicoil and no reason to believe the bottom end had been touched previously.
#
The factory must have got a bulk deal on the standard length coil as it is the same as the 750.
The 850 case could have got a 2D coil maybe longer with the thicker primary wall in that area.
If you are going to tap all the way for an insert, why not utilise that instead of half of it.
The 850 it seems has Helicoil there and at the engine case oil pipe junction, oil pump studs and 4 long cylinder cap screws.
Onder
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My 850 is 312xxx feb 74 the helicoils, oddly enough, do seem be be short, filling maybe half the bore with the helicoil
wire. This bothered me as it seems you need all the grip available. And I know that Esme got new hex screws from AN and they were zinc plated and she binned them. AN's page shows them to be plated and states it. Question, of course, is "are they hardened?"
And the usual disclaimer "could I possibly be over thinking this?"....naw, impossible ;-O
wire. This bothered me as it seems you need all the grip available. And I know that Esme got new hex screws from AN and they were zinc plated and she binned them. AN's page shows them to be plated and states it. Question, of course, is "are they hardened?"
And the usual disclaimer "could I possibly be over thinking this?"....naw, impossible ;-O
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