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+--- Thread: Loss of power under load (/showthread.php?tid=4748)
RE: Loss of power under load - AustinWood - 10-08-2020
We had a problem with the 1929 saloon. It ran well but started to develop a misfire if high revs had been used for long. Typically climbing hills in 2nd gear.
It was OK at higher revs but as soon as we changed up into top the car would stumble and not pull properly. This gradually got worse and worse and eventually wouldn't pull properly at all.
After trying everything I could think of I eventually removed the head and found that numbers 3 & 4 exhaust valves were sticking. On removing them found there was a build up of carbon on the stems which caused this. I cleaned everything up and reassembled it and all was well.
I think what was happening was that the exhaust valves were getting hot with the continuous high speed and had expanded more than usual hence not closing properly.
I adjusted the exhaust valves 0.002" wider clearance. No more problems.
RE: Loss of power under load - Peter Naulls - 10-08-2020
It's a Lucas dizzy Nick.
It will be a while before I get back to it. I may rig up a temporary petrol tank just to eliminate the possibility. I will also change the distributor base plate back to a standard one and fit an earth lead and a new cap, other than that the head is coming off.
Thanks again for all the suggestions.