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Loss of Power Upon Acceleration

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hama61

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Good day all,

I have the following question and wonder if there is a plan by following certain steps how to solve below problem.

The BN4 starts normally, but when driving and you exceed around 2500 RPM the engine tends to be flooded. As long you are below 2500 RPM and keep the throttle steady, it is fine. Acceleration results in power loss of the engine.

Which steps do I have to follow trying to solve this issue?

Thanks in advance,

Harry
 
hama61 said:
Good day all,

I have the following question and wonder, if there is a plan by following certain steps how to solve below problem.

The BN 4 starts normally but when driving and you exceed around 2500 rpm the engine tends to be flooded . As long you are below 2500 rpm and keep the trottle steady it is fine. Accelerate results in powerloss of the engine.

Which steps dod i have to follow trying to solve this issue

Thanks in advance,

Harry
Click to expand...
Is this a new problem? My initial thought - have you checked the dashpot oil?
 
What makes you think it's flooding? More gas usually make a car go faster. Have you checked your timing?
 
Bonjour
Ce type de problème peut survenir dans 3 cas....

1 - le niveau des flotteurs dans les cuves est trop bas
vérifier ce niveau mais en faisant attention, car il y a plusieurs réglages selon la référence des carburateurs (voir notice technique)

2 le timing n'est pas bon (trop tard) pour bien faire ça, régler à 31° moteur vers 3500 tr/mn...

3 la richesse en carburation n'est pas bonne, pour cela montre nous tes bougies (photo) selon la couleur, on pourra dire si c'est suffisant
 
Good morning
This type of problem can occur in 3 cases....

1 - the level of the floats in the tanks is too low
check this level but being careful, because there are several settings depending on the reference of the carburettors (see technical manual)

2 the timing is not good (too late) to do this well, adjust to 31° engine around 3500 rpm...

3 the carburation richness is not good, for that show us your spark plugs (photo) according to the color, we will be able to say if it is sufficient
 
Hello,

After a short drive just before the post I have parked the car. Yesterday after returning from holiday I made several attempt to start the car (eventually even with a booster spraying the carbs, but without success). I hear the pump ticking the engine turns over.

As a side note when the car was still running and the engine was switched off (it was shaken).

@BobHaskell
dashpot oil checked and is fine

@ Boyracer
I assume that in order to check the timing you will need a timing light.

@TONTONGUIGUI
Maybe it is a timing question, but need to have to car running to check.

@ JohnTurney
How can you determine, if the distributor is working properly?

Thanks in advance for the input.

Harry
 
Some things I have tried when having a problem such as you describe. Others more knowledgeable may offer better suggestions. I might try replacing the points, condenser, rotor and coil. Also check low-tension leads and that the distributer pinch clamp bolt is tight. I might also remove a spark plug to check for unburned fuel and while it's out, connect the lead and ground it to the engine, darken the garage then crank the engine to see if there is a spark. It is possible to check static timing using a 12v lamp. I believe the process is described in one of the shop manuals.
 
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