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Metric conversion

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GaryBeu

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I'm not sure this is appropriate for the Pub but wasn't sure where to go with it...I'm fighting bolt heads, etc. for size on my MGB. Is there a chart somewhere that compares mm to inches? Right now I have one that is just smaller than a 9/16" wrench. Thanks.
 
Gary -

Hardware on MGB's are all SAE. No metric fasteners from the factory, as far as I know. Others?
 
Thanks Mickey but...turned out that the bolts on the clutch slave cylinder seemed to be a 14mm :( ???
 
Yeah DNK, they are. The 9/16 was sloppy and the 14mm was just right. Still wish I could find a conversion chart somewhere...
 
Doing the math, find the decimal of the SAE wrench. Then multiply by 25.4 ( how many millimeters in an inch). So 9/16= .5625inch*25.4mm=14.29mm.
 
5/16-8mm
3/8-forget about it, it aint happening (if substituting for a 10mm wrench the same is true)
7/16-11mm
1/2-12,13 depending on the wrench, bolt/nut and hammer I have handy
9/16- 13,14 see above
5/8-15mm
11/16-17mm IIRC
3/4-19mm IIRC
7/8-21 or22 mm IIRC
 
Thanks ya'll...I appreciate the info and will hang on to it. :smile:
 
The best way to find SAE tools to fit metric fasteners (and vice-versa) is to the buy the cheapest Chinese/Taiwanese tools you can locate. High quality tools usually fit the intended fastener too well to be cross-purposed.
 
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Problem we find with these cars is over the years, some of them have not been maintained by professional mechanics when they were not collectors pieces. Because of this we find that other than original bolts and screws have been replaced by whatever. I think my 55 TF had 20 % of it's original bolts and screws in it. Even had bolts with the wrong threads. I had to buy special taps and dies to refurbish the British threads. As Forrest said, " It's like a box of chocolates, you never know what your going to get"! :highly_amused: PJ
 
There should not be any metric fasteners in that MG. OTOH, I was having a serious problem removing the starter on a friend's Mercedes 170v some time ago. The fasteners are by feel only and I just could not get on them to turn. When I finally got it out, I found and later verified that a British car mechanic friend had worked on it at some time and replaced it with what he had on hand, 1/2 inch bolts instead of 12 mm. Arghhhh.:mad:
 
The only non-SAE fasteners I can recall on any MGB are the filler hole bolts on the shock dampers... and they're Rudge/British Standard, IIRC.
 
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