Any thoughts/suggestions would be appreciated. Bit of background, We have had our late bay for 12+ years and drove thousands of miles with no problems. It has been off the road for approximately five years whilst I fixed up the bodywork and took the engine out to spray in the engine bay, cleaned everything up including the petrol tank and put it all back in as it was(?). The first outing was a few miles for an MOT which it passed with no problems. Next journey to Wilshers Garage for Peter Baldwin to put on the rolling road. On the way there the engine just cut out but started immediately and I figured if there was a problem he would pick it up, and other than replacing n/s carb gasket and slight airleak o/s manifold/carb joint all was good on the rolling road. A few miles into the journey home it cut out again and so I took it straight back to Peter, he said he had noticed the carb icing when I drove in but checked evrything over and said it must be icing as it was a cold damp day. Next journey down to Poole to have a new poptop canvas fitted when it cut out on several occassions but always starts immediately again very cold and/or wet days. so again we put it down to the iceing problem. We have been fitting an interior and so not driven it any distance since, however this warm dry weekend we went approx 30 miles and the same thing happened, but the journey back was fine. There is no pattern to this it can go 100 miles with no problem then cut out three times in 50 miles, mostly just crusing on dual carriageways or decreasing speed for roundabouts for accelerating for sliproads. It is not a conventional set-up W code 1700 engine with twin SU carbs , however it has never been a problems in all the years we have had it until now. Sorry for the long essay, but I have tried to give as much infomation to help with any possible diagnosis. Any ideas welcome as we are booked on a ferry to France in a weeks time.
Can you post a pic of what set up you have? What air filter do you have and are they SU carbs as on a BL car with the dash pot on the top with the felt pad in?
I hope this helps, these were obviously taken when it was out of the van and has sat about in the shed for a while. View attachment 3635 View attachment 3635 I
Carb icing! – I used to get that when I flew old carb aircraft – Carb icing can happen when there is high humidity and low engine power. However The only remedy is to get warm air to the intake from a pipe fitted near the exhaust – but warm air reduces power! Some car and bike companies had this problem and had to alter the way the air got to the carbs – so it could be down to the design – You could lash up a Heath Robinson affair (a pipe nr the exhaust leading to the top of the carb with a on / off flap leading to the cab) and when you feel the drop in HP you could open up the “carb heat” until there was smooth running, and then shut it– that’s how it’s done in a plane – can you believe it!!!
Can you put in a small pipe to bleed a bit of warm air into the pancakes? this may just tip the scales for you
Thanks for replying, It is very Heath Robinson in there anyway, so I am sure it could be added to, however I suppose the question I am asking is could you get carb iceing on a warm dry day as this was at the weekend, or should I be looking at the problem being somewhere else?
Its all down to the relative humidity - water vapour - and its more humid in summer than winter - ie - if its cold and frosty there is less chance of the carbs icing - warm and sweaty days - and these are the days you will more likely get carb icing. I think you only option is to get a bit of warm air to the carbs - but not to much as it will cause a loss of power
