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Running on

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H

Hoghead

Jedi Trainee
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My BJ8 runs on after shutting off the key and I have to kill it with the clutch

Distributor is rebuilt by Advance Distributors, new platinum plugs, carbs rebuilt by Joe Curito. No idea why this is happening other than too hot a plug or the sew style plugs with more exposed electrode than the older designs

Ideas?
 
Idle speed a bit too high as well as engine temp.
 
It does it at 190F (assuming the gauge is correct), so should not be temp related

It will not idle down any lower and is about 850.
 
Maybe I'm unique but I've never met one that didn't want to run-on especially if the head has been skimmed and the compression ratio increased - keep using your clutch to stop it. It may not be too hot based on the water temp, but these tend to run fairly high exhaust temps and the exhaust valve gets pretty hot so I agree with Keoke, if you can get the idle a bit lower and richen it up a bit it may stop running on. Running a bit rich cools the exhaust valve as fuel droplets hit the combustion chamber and exhaust valve and therefore helps with run-on. johnea is right too, retarded timing makes for a hot combustion chamber. But I always stop mine with the clutch. This is my experience, your experience may vary.
 
Engine is new so there should be no carbon. The head was milled during the rebuild but I am sure it was a minimal amount
Fuel is 91 octane and it does it on both straight petrol and E10
I thought to lighten the flywheel and in the end did not - too late now.
 
Hog,

Try running Shell 93 and put a little Octane Boost. I use Lucas or Bardahl's. I put 1/3 bottle every 3 or 4 fill-ups and I only use Shell 93. I used to have dieseling or run-on until I used only Shell 93 and a little octane boost. You get carbon deposits on your cylinder walls which is probably the cause of your run-on.

John B
 
No idea why this is happening other than too hot a plug or the sew style plugs with more exposed electrode than the older designs:
:savewave:
BOSCH WR7DP is OK.
 
I too suspect the plugs and will try this now

Fuel choice is limited to what one can buy and booster is a PITA. After all compression is low. In any case of the plugs do not work than I will try to find better fuel as a test
 
Nothing wrong with your engine, timing or anything else... Simply a case of the current fuel quality... There is residual fuel in the chamber that continues to ignite due to the high temperature/carbon build up... Use 98 octane or higher if you can.. this will reduce the run on... Its annoying I agree but absolutely no damage to the engine...
 
Henry Manney, probably the greatest automotive writer ever once said: "There will always be an England because once the engine is shut off it will keep running on." My '65 3000 with original but rebuilt distributor, timing set at manual recommendation, use 89 octane gas, carbs set with tube in ear, has never had running on, but 67 Etype with same as above runs on for a few secs and then stops.
Jay
 
Its annoying I agree but absolutely no damage to the engine...

IF!! you stop it within a few seconds by using the clutch.
 
Keoke I assume that like most that the car is in neutral with the hand brake on before cutting the ignition switch... so at that point the role of the clutch has no effect whatsoever on the engine, fuel, etc as its mechanical.. I am happy to learn a new trick but why use the clutch ?
 
andrewss said:
Keoke I assume that like most that the car is in neutral with the hand brake on before cutting the ignition switch...
Click to expand...
I always have the car in gear when parked, even on my modern cars. With the foot on the brake, clutch in, tranny in gear, ignition off, release the clutch to stop run-on. Run-on will be a little different for every car, so you'll need to find the least violent way to use this method for your car.
 
Keoke I assume that like most that the car is in neutral with the hand brake on before cutting the ignition switch.

Naw:Andrewss
We don't do it like that on this side of the pond.

SEE:
I always have the car in gear when parked, even on my modern cars. With the foot on the brake, clutch in, tranny in gear, ignition off, release the clutch to stop run-on. Run-on will be a little different for every car, so you'll need to find the least violent way to use this method for your car.

OH!!-Me too--Greg :encouragement:


user-online.png
 
You can try just turning the car off with the clutch pedal depressed, since the carbon release bearing tends to slow the engine ( that's why it's easier to crank a cold engine in neutral with your foot off the clutch ). Or you can stall the engine, by turning it off with your foot on the clutch, in gear, handbrake on, and coming slowly off the clutch.
Bob
 
Back off timing, reset points , idle down, lean carbs a little, regulate fuel pump, more octane. Some of the dos.
 
I don't have a running on problem but if the problem is due to carbon buildup this product might work. My son's van failed his emissions test and at my suggestion he went to the neighborhood autoparts store and got it then he added it and went back to the inspection station(half hour drive), and was tested again and he passed. The guys there couldn't believe it and rechecked his van twice. It's advertised on that Saturday morning show talk show "Wheels, with Ed Wallace".
 
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