18-09-2017, 04:51 PM
Hi all,
I am a comparative newcomer to the A7 scene. I have a 1933 RP that, until recently, has been running very reliably and well.
However, recently it has developed a problem.
SYMPTOMS
It will start with full choke and revs freely, but as soon as I attempt to reduce the amount of choke, the engine runs for a second or so then dies. If I return choke to 100% quickly enough, I can prevent it from dying, and it will rev its nuts-off again.
This revving is accompanied by CLOUDS of white-ish smoke from exhaust.
If I persevere, I can eventually nurse the engine by running on choke, until engine is warm and then it will run reasonably smoothly without choke.
ACTION TAKEN
I have swapped Carbs.
Swapped Fuel Pump
Replaced Condenser with a new one.
Checked points and plug gaps.
Cleaned carb(s) repeatedly.
Fresh Fuel.
Fuel pump is delivering fuel.
I get a big fat spark.
Checked for obvious air leaks, none found.
Checked compression (engine cold, throttle fully open, turnover by starter motor. Readings were 1=95, 2=87, 3= 100, 4=95 )
MY ASSUMPTIONS
Need for choke suggests air leak and/or fuel starvation (but have cleaned carb, changed carb.?)
White smoke suggest Head Gasket (about to take head off and change gasket/inspect head, but wouldn’t have thought this would have cause the erratic running/starting pattern I am experiencing?)
Compression readings suggest nothing too seriously wrong with rings and valves (although number 2 is lower than other 3 cylinders)
I must admit to being out of my depth, if changing the head gasket doesn’t cure problem………. I will be out of ideas/experience/knowledge.
Any suggestions will be gratefully received.
PS. If I have inadvertently broken some protocol in posting this, I apologise in advance, it’s my first go.
I am a comparative newcomer to the A7 scene. I have a 1933 RP that, until recently, has been running very reliably and well.
However, recently it has developed a problem.
SYMPTOMS
It will start with full choke and revs freely, but as soon as I attempt to reduce the amount of choke, the engine runs for a second or so then dies. If I return choke to 100% quickly enough, I can prevent it from dying, and it will rev its nuts-off again.
This revving is accompanied by CLOUDS of white-ish smoke from exhaust.
If I persevere, I can eventually nurse the engine by running on choke, until engine is warm and then it will run reasonably smoothly without choke.
ACTION TAKEN
I have swapped Carbs.
Swapped Fuel Pump
Replaced Condenser with a new one.
Checked points and plug gaps.
Cleaned carb(s) repeatedly.
Fresh Fuel.
Fuel pump is delivering fuel.
I get a big fat spark.
Checked for obvious air leaks, none found.
Checked compression (engine cold, throttle fully open, turnover by starter motor. Readings were 1=95, 2=87, 3= 100, 4=95 )
MY ASSUMPTIONS
Need for choke suggests air leak and/or fuel starvation (but have cleaned carb, changed carb.?)
White smoke suggest Head Gasket (about to take head off and change gasket/inspect head, but wouldn’t have thought this would have cause the erratic running/starting pattern I am experiencing?)
Compression readings suggest nothing too seriously wrong with rings and valves (although number 2 is lower than other 3 cylinders)
I must admit to being out of my depth, if changing the head gasket doesn’t cure problem………. I will be out of ideas/experience/knowledge.
Any suggestions will be gratefully received.
PS. If I have inadvertently broken some protocol in posting this, I apologise in advance, it’s my first go.