GatesDavid@aol.com wrote:
>
> Can anyone please let me know what the compression on a 1500 should be? I
> can't seem to find it anywhere in my Haynes manual. I'm going to buy a '78
> Spit 1500 today (see thread "Possible parts car") but the price will depend
> somewhat on the engine condition (its not running now) and I think a
> compression test is probably the easiest and most telling indication of the
> engine, but I can't remember what a good reading is.
>
> Thanks,
> David Gates
> '73 spit 1500
> '78 spit 1500 (soon)
> Hawaii
> http://members.aol.com/gatesdavid/index.htm
David,
The US and Canadian Spec 1500's were 7.5 to 1. UK cars were 9 to 1.
The info shows up in the #113 Haynes Manual 62-81 Spitfire on page 27
three lines from the bottom of the page. I have also checked and
confirmed this in the Bentley Manual and Michael Cook's book on "our
favorite car"! Good luck in your upcoming purchase.
Ron Fowler
'80 Inca Yellow with OD
Joe Curry wrote:
>Ron,
>I don't think that was what he asked. I think he wants to know what the
>readings should be when he checks the compression.
Joe
Good Point Joe! (Brain dead at my house today - RF)
David,
I haven't been able to locate the info requested in the Haynes Manual or
others for the '78 1500 in question. The 1975-80 Bentley Manual states
that the the check for cylinder pressures (page 124) should show that
all cylinders should have pressures within 10 lb/in squared (0.70 kg/cm
squared) differential.
Procedure from Bentley Manual:
1. Run engine to normal operating temp.
2. Remove the spark plugs.
3. Fit compression gauge to #4 cylinder.
4. Turn engine over with starter motor with throttle wide open.
5. Note and record gauge reading.
6. Repeat on the remaining cylinders.
The Haynes Manual does list the US low compression 7.0 to 1 1147cc and
7.5 to 1 1296cc engines at 130lbf/square inch. It notes the UK high
compression 9.0 to 1 1147cc and 8.5 to 1 1296cc engines at 144 and 140
lbf/square inch respectively. (Pages 24, 26)
I would think that checking for major variances between cylinders would
be a good way of checking the engine condition as to the value for
purchase.
Best of luck,
Ron Fowler
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