The V8 Owners Forum -

I have been loaned an exhaust analyser that measures Carbon Monoxide levels and intend to give my carbs a bit of a tune up.

Is the idea to get as low CO reading as possible???

Could I use it to check if I need to swap needles by measuring CO2 levels at different rev ranges?

Thanks

Jon

Can anyone help me with this?

Today I have tried using both the CO meter and the lifting pin method of adjusting the SU's on my 3.5.

Following the landrover manual I have adjusted the jet until its flush with the bridge and then turned the mixture screw 3.5 turns clockwise on both carbs. After reaching this datum I had a CO level of 8% I started to adjust the mixture screws leaner by equal amounts and as I dod this the idle speed increased. I reset the idle speed and leaned the mixture a bit and adjusted the idle etc. I kept on doing this aiming for the manuals recomended CO level of 0.5 to 2.5%. At about 5% the idle speed started to fall as I adjusted the carbs leaner and I had to increase it to stop the engine from stalling.

I stopped at a CO level of around 1% but if I lift the pins on the carbs the engine speed plumets and it stalls.

The lifting pin method would indicate that I need to enrichen the mixture but if I get it to a point where lifting the pins raises the idle speed slightly but then settles down straight away (which I have read is the desired result) I have a CO level of 6%

Can anyone clear this up for me?

Cheers

Jon

AFAIK
the CO should be c3.5% for good idle on RV8 3.5's, 1% is too low.

Kev