3000s running on
Discussion
I had some running on problems now and then on my 3000S very strange.
So
1. i looked at the Spark Plugs colours and they were White. There was hesitation at slow opening of throttle.
2. i looked at the Idle Jet sizes and they were 50.
3. i changed them to 55 to see what would happen. I found the Spark Plugs started to get a little colour and the running on stopped. But still a very slight hesitation at very slow opening of throttle.
4. i went up on Idle Jets to 60. I found the Spark Plugs Hazel nut colour perfect. No running on and no hesitation at very slow opening of throttle.
Perfect running now.
Conclusion is when the Engine was rebuilt with a different Camshaft the Carb had never been set up correctly and with the Modern Fuels now it doesn't help.
I hope this can be of use for someone else.
Alan
So
1. i looked at the Spark Plugs colours and they were White. There was hesitation at slow opening of throttle.
2. i looked at the Idle Jet sizes and they were 50.
3. i changed them to 55 to see what would happen. I found the Spark Plugs started to get a little colour and the running on stopped. But still a very slight hesitation at very slow opening of throttle.
4. i went up on Idle Jets to 60. I found the Spark Plugs Hazel nut colour perfect. No running on and no hesitation at very slow opening of throttle.
Perfect running now.
Conclusion is when the Engine was rebuilt with a different Camshaft the Carb had never been set up correctly and with the Modern Fuels now it doesn't help.
I hope this can be of use for someone else.
Alan
Yes i agree if i lived near John Wade or someone who knows Essex Engines.
I live in Brittany France.
But now i have no running on and the Spark Plugs have a good colour.
I might look at fitting a Lambda Kit some day to monitor the AFR.
It was more as info for others that find thier car does not pick up cleanly when the Throttle is opened very slowly from 1,000rpm. Also they suffer from running on when Engine is very hot.
I hope this will help and the cost of Idle Jets is very cheap.
Alan
I live in Brittany France.
But now i have no running on and the Spark Plugs have a good colour.
I might look at fitting a Lambda Kit some day to monitor the AFR.
It was more as info for others that find thier car does not pick up cleanly when the Throttle is opened very slowly from 1,000rpm. Also they suffer from running on when Engine is very hot.
I hope this will help and the cost of Idle Jets is very cheap.
Alan
No problem.
The problem was not weak at tickover because that is corrected by turning the tickover screw out to richen mix on tickover.
Idle Jets in real life are "Transition Jets" which feed the Engine from tickover upto when the Main Jets start to operate which can be from 2,000rpm upwards. A lot of driving is done at low rpm when the Idle Jet is the only Jet feeding the Engine.
The going up in Idle Jet size was just a little tweek to remove a very slight hesitation during the transition from Tickover to about 1700rpm.
Plus improve Plug colour and stop Running on.
I think a better name for Idle Jet would be Transition Jet.
Now there is no Running On and Plug colour is correct. The Idle Screws are also 1/2 turn off their Seats.
Alan
ps. if the Idle screws are too far off their seats that indicates that Idle Jets are too small
The problem was not weak at tickover because that is corrected by turning the tickover screw out to richen mix on tickover.
Idle Jets in real life are "Transition Jets" which feed the Engine from tickover upto when the Main Jets start to operate which can be from 2,000rpm upwards. A lot of driving is done at low rpm when the Idle Jet is the only Jet feeding the Engine.
The going up in Idle Jet size was just a little tweek to remove a very slight hesitation during the transition from Tickover to about 1700rpm.
Plus improve Plug colour and stop Running on.
I think a better name for Idle Jet would be Transition Jet.
Now there is no Running On and Plug colour is correct. The Idle Screws are also 1/2 turn off their Seats.
Alan
ps. if the Idle screws are too far off their seats that indicates that Idle Jets are too small
Edited by plasticpig72 on Friday 5th June 10:18
Edited by plasticpig72 on Saturday 6th June 15:37
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