Re: New member from France with a 1986 Aero 50
Posted: Wed Mar 19, 2014 2:42 pm
EDITED to complete.
Honda says 100Ôé¼ +/-...
for the bystarter.
I am doing the tests by the shop manual.
First test : resistance of the by starter.
I measured 4.3 ohms.
Supposed to be 10 ohms...maximum. But what should the minimum be?
2 other tests to do :
1┬░ Carb sitting for 30 mins, apply pressure (Mityvac pump for example) to the enrichening circuit. Passage blocked : change the bystarter.
2┬░ Connect the bystarter to battery and wait 5 mins. Apply pressure the same way. Passage without restriction : change bystarter.
I'll be back.
Test 1┬░ : passage is not blocked. So is ok.
Test 2┬░ : passage is not completely blocked. The pressure will not stay in place. So is not ok.
Symptoms :
When the engine is started at cold, it revs waaaaay too high.
When the engine is running at hot, it slowly stalls.
I can manage to keep it idling if I fiddle with the throttle from time to time.
Checking the plug : it is wet when idling.
I have found a link that explains, in french, how these bystarters work :
http://www.club-scootergt.com/tutoriels ... tique.html
There are pictures clear enough to illustrate what I'm explaining just after.
To make it short :
The piston in the bystarter is pushed down by wax contained in a cylinder. The wax is heated electrically.
In about 5 mins, the piston should be all the way down and cut out the choke circuit.
I used to have a Daimler Double Six which had an Additionnal Air Valve.
The wax was heated by the collant fluid of the engine.
This AAV was often causing problems when ageing.
Wax was "lost" and the piston, at cold start, was letting too much air in : idle at cold was too high.
When hot, the piston was still letting too much air, you could correct this with the idle screw. But the cold starting was too low then.
I saved my AAV by taking it apart and "squeezing" the cylinder containing the wax to get the piston to the original height (I knew that height because someone had measured it on a new one).
I think my bystarter has the same problem here. By some means the piston is too high at cold and can't get low enough when heated to cut out the choke circuit.
I don't think I can't take it apart, it looks like it is sealed.
Moreover I don't know what the normal piston height should be....
So I will have to change it. If the new one works, I may cut it open to see how it is inside...
Honda says 100Ôé¼ +/-...
for the bystarter.I am doing the tests by the shop manual.
First test : resistance of the by starter.
I measured 4.3 ohms.
Supposed to be 10 ohms...maximum. But what should the minimum be?
2 other tests to do :
1┬░ Carb sitting for 30 mins, apply pressure (Mityvac pump for example) to the enrichening circuit. Passage blocked : change the bystarter.
2┬░ Connect the bystarter to battery and wait 5 mins. Apply pressure the same way. Passage without restriction : change bystarter.
I'll be back.
Test 1┬░ : passage is not blocked. So is ok.
Test 2┬░ : passage is not completely blocked. The pressure will not stay in place. So is not ok.
Symptoms :
When the engine is started at cold, it revs waaaaay too high.
When the engine is running at hot, it slowly stalls.
I can manage to keep it idling if I fiddle with the throttle from time to time.
Checking the plug : it is wet when idling.
I have found a link that explains, in french, how these bystarters work :
http://www.club-scootergt.com/tutoriels ... tique.html
There are pictures clear enough to illustrate what I'm explaining just after.
To make it short :
The piston in the bystarter is pushed down by wax contained in a cylinder. The wax is heated electrically.
In about 5 mins, the piston should be all the way down and cut out the choke circuit.
I used to have a Daimler Double Six which had an Additionnal Air Valve.
The wax was heated by the collant fluid of the engine.
This AAV was often causing problems when ageing.
Wax was "lost" and the piston, at cold start, was letting too much air in : idle at cold was too high.
When hot, the piston was still letting too much air, you could correct this with the idle screw. But the cold starting was too low then.
I saved my AAV by taking it apart and "squeezing" the cylinder containing the wax to get the piston to the original height (I knew that height because someone had measured it on a new one).
I think my bystarter has the same problem here. By some means the piston is too high at cold and can't get low enough when heated to cut out the choke circuit.
I don't think I can't take it apart, it looks like it is sealed.
Moreover I don't know what the normal piston height should be....
So I will have to change it. If the new one works, I may cut it open to see how it is inside...
)!
