rickwrench
Famous Member
Often the cure for dieseling after shutoff is to use the next higher grade of gas. More octane = controlled burn. Try a tank and see what happens.
Rick(wrench)a
Rick(wrench)a
Great mpg, mildly surprised.
- Thread starter rickwrench
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Anonymous
Guest
With my old engine it diseled all the time. I have my friend, who just graduated from WYO TECH (a high performance school in wyoming for hot rods etc) come and set up my old motor and he couldent get it to stop. He said though that to shut the car off while its still in gear, for some reason that got it to stop dieseling. Never did it after that as long as i shut it off while still in drive or reverse. Havent had that problem yet with the new motor. Of course I just broke 100 miles on it today.
As far as fuel economy goes, I was getting about 14 with my old engine. Havent done it yet with my new one. I dont think Im gonna get a consistant reading though untill its broken in.
As far as fuel economy goes, I was getting about 14 with my old engine. Havent done it yet with my new one. I dont think Im gonna get a consistant reading though untill its broken in.
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Anonymous
Guest
I have noticed and regularly do shut off the car in gear and it does help alot of the time but not all the time. Sometimes you just end up sounding really stupid rumbling up to somplace in your cool car and then when you turn it off it goes chugachugaputtputtffffffffffftttt...
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Anonymous
Guest
Deiseling was a big problem with my F150 when I bought it about a year ago. After driving it on 89 octane for awhile I decided that it was time to get serious with a viable solution to my problem.
First, I did a lot of research into these trucks and found out that deiseling was bound to happen sometime in the trucks life time. From the factory, in order to meet stringent emmision standards just passed my congress a few years before - Ford had to severally retard the timing and use warmer spark plugs in order to promote a cleaner burn. Well, that may have been a short term solution but long term - big problems later.
So, I rebuild the carburetor, installed cooler plugs (Bousch Platinum), new 8mm spark plug wires and advanced the timing by about 5 degrees. BIG difference. Smoother idle and a bigger "punch" at takeoff. I even saw a 3 mpg increase. But best of all, no more deiseling - even with 87 octane.
-Chris
First, I did a lot of research into these trucks and found out that deiseling was bound to happen sometime in the trucks life time. From the factory, in order to meet stringent emmision standards just passed my congress a few years before - Ford had to severally retard the timing and use warmer spark plugs in order to promote a cleaner burn. Well, that may have been a short term solution but long term - big problems later.
So, I rebuild the carburetor, installed cooler plugs (Bousch Platinum), new 8mm spark plug wires and advanced the timing by about 5 degrees. BIG difference. Smoother idle and a bigger "punch" at takeoff. I even saw a 3 mpg increase. But best of all, no more deiseling - even with 87 octane.
-Chris
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Anonymous
Guest
When I first got my '66 Pontiac GTO clone, it dieseled like crazy. It had almost everything that could cause dieseling happening. A vacuum leak on the brake booster could have been helping it run hot. An emissions distributor, retarded the timing. A lopey cam combined with retarded ignition led to the previous owner setting the throttle plates too far open. Now that I have straightened out the timing and vacuum leak, I occasionally get some dieseling. However, I suspect I am in need of a new radiator, because it still seems to run hot even during the mild days. We still are looking at gaining another 30 degrees of daytime temps, when summer hits.
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Anonymous
Guest
Dieseling, or 'run-on', as manufacturers call it, is caused by one of two scenarios:
1. too much fuel in the mix at idle speed. This can be caused by too high of an idle or the air adjust screw turned out too far.
2. overheated chambers (not the same as overheated engine). This can come from spark plugs that are too hot for the fuel in use, or retarded timing (relative to the fuel in use) or over-advanced timing (like when manifold vacuum is used instead of port vacuum or none at all, like pollution-controlled engines).
Sometimes, carbon buildup in the cylinders can cause it, too. Running a can of BG44 through a tank of gas usually clears this up nicely.
1. too much fuel in the mix at idle speed. This can be caused by too high of an idle or the air adjust screw turned out too far.
2. overheated chambers (not the same as overheated engine). This can come from spark plugs that are too hot for the fuel in use, or retarded timing (relative to the fuel in use) or over-advanced timing (like when manifold vacuum is used instead of port vacuum or none at all, like pollution-controlled engines).
Sometimes, carbon buildup in the cylinders can cause it, too. Running a can of BG44 through a tank of gas usually clears this up nicely.
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Anonymous
Guest
or u can run hydrogen like i do to get rid of the carbon... 
.....just a question...do u use cooler spark plugs if u have a hotter combustion...cause i think the hydrogen is creating a hotter burn..do i need hotter or colder plugs??? I dont deisel, but if it matters....*my air screw is turned way out cause thats where it runs smoothest...if i turn it in it will sputter...wil changing the timing solve this if i turn the screw in???
.....just a question...do u use cooler spark plugs if u have a hotter combustion...cause i think the hydrogen is creating a hotter burn..do i need hotter or colder plugs??? I dont deisel, but if it matters....*my air screw is turned way out cause thats where it runs smoothest...if i turn it in it will sputter...wil changing the timing solve this if i turn the screw in???
