"Tom Woods" wrote in message
...
My car has just failed its MOT test on emissions.

it is running a simple open loop gas kit with a mixer before the carb.

apprently it was

at 2500rpm - CO 0.07%, HC 3380ppm
at idle, HC 8000ppm+

Any suggestions as to how i should go about sorting this?

I have changed the air filter (which was 1 year old and dodnt look too
bad).
Before the MOT i set the points (which smoothed the idle out)

Can the timing being off affect it too?

Bloody hell, 8000ppm+ !!!!

Yes retarded igntion timing will create high HC's on LPG even if the CO is
good.

I would also say its running too rich as well as with wrong timing. Also
check the cam timing..

What engine is it??

Tim.

"Tom Woods" wrote in message
...
On Sun, 8 Oct 2006 16:18:14 +0100, "Tim.."
wrote:

Yes retarded igntion timing will create high HC's on LPG even if the CO is
good.

I would also say its running too rich as well as with wrong timing. Also
check the cam timing..

How could it be running rich if the CO reading was good? I was
actually considering turning it up a tad since in my experience HC's
go down as CO goes up?

Sorry, i indeed meant to type LEAN, not rich!

Any secondary emissions controls on this engine which might be playing up??

Tim..

"Tom Woods" wrote in message ...
On Mon, 9 Oct 2006 09:03:52 +0100, "Tim.."
wrote:

Any secondary emissions controls on this engine which might be playing up??

Nowp. They fortunately didnt have anythihg silly like that in 1980
vintage cars!

The only thing im not sure about is the breather that goes from the
cam cover to the air box, though most engines have those dont they?
I'm never sure what purpose they serve though!



the breather is so that the oil fumes and spay thet you get from the breather is taken through the inlet and out through the exhaust.
without it the oil would cover the engine bay over time.

"Tom Woods" wrote in message ...
On Mon, 09 Oct 2006 10:50:43 GMT, "bongo rule"
- wrote:

the breather is so that the oil fumes and spay thet you get from the breather is taken through the inlet and out through the exhaust.
without it the oil would cover the engine bay over time.


Does that not contribute to the HC's level too then?

yes possibly.

but i would have thought for it to make any differance the ring/cylinders or valve guides must be worn