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Front camshaft bushes
#1
What's the OD of the front cam bush fitted to standard coil engine cars?

I did have a note of this but can't fine it when I need it!

Thanks

Charles
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#2
There seems to be more than one diameter, this cam bush came out of a scrap 1 5/16" three speed crankcase. It needed the OD skimming down (about .030" from memory) to fit in the 1 1/8" three speed crankcase that replaced it.

[Image: 49781127122_28960962fe_z.jpg]
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#3
At least two sizes exist.

1.530"

and

1.5"

I suspect the change occurred at the same time as the rear bush enlarged also.
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#4
Thanks Chaps

I've only got mag engines here and they are 1.500" and that ties up with the smaller ID to suit the thinner front cam journal.
In my memory I have 1.5625 in my mind (1 9/16" in Austin's terms) for coil engines (when the journal got bigger) but it could be 1.530". I did have at least one coil cam bush but as I've said, it has eluded capture.


c
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#5
Hi Charles,
I have a few bushes scattered about in the garage and garden shed mostly from two bearing coil engines, I will have a rummage later and measure a few with the digital calipers for you.
I have got a Nippy one as well which gives room for the high lift cam, the centre bearing is larger for this as well.
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#6
Hi Charles,
I found them,
Two measure 1.528"
Two measure 1.529"
Nippy 1.612"
I hope this helps
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#7
Brilliant, thanks

That suggests a nominal 1.530
If you want to part with one, I'm a willing customer!

Best wishes 

C
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#8
I've just been sorting out my two bushes, which measure:

RP
O/D = 38.81mm /1.528" (1 17/32" ??)
I/D = 22.18mm / 0.874" (7/8")
Length = 36.04mm  / 1.4189" (1 7/16")
Camshaft o/d = 22.17mm

Type 65
O/D = 41.2 mm / 1.622"  (1 5/8")
Length = RP = 1 7/16"
I/D = 1.000"

I've just got some aluminium stock in so as to have a dry run at making a bush for the RP before splashing out on some SAE660 bronze, which I think is the correct stuff for the bearing?

An after thought, I know the location hole for the front bush is dimension X from the flange on the camshaft, and so alignment of the timing gears can be obtained by lapping the cam gear and trimming the camshaft bush, or shaving the crankshaft gear. Does anyone know what X is please? My previous endeavours in this area have relied on having a pattern and a bit of dead reckoning.
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#9
Colin,

Don't put too much faith in this but I have a drawing I made many years ago when I had a (3-brg) case plugged and re-drilled, I placed the locating bolt hole 1.875" back from the front cover joint face. That engine is still running! If this for an engine with 1.5" big ends I'd worry more about cam clearance than perfect alignment of the gears..

I recently bought SAE660 bronze for a gearbox bush, worth a look at "Metals4U", priced reasonably and they will supply small pieces as required. Also in 'tubular' form for bushings.
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#10
Metals4U still working and delivering quickly. Ordered Monday, delivered Wednesday this week. Recommended.

Steve
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