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  #1  
Old 08-07-12, 21:19
Lauren Child Lauren Child is offline
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Default Lack of power (can't accelerate in third gear)

Blimey, I seem to be going from one thing to another on Dolly (FGT F22)

Today I managed to spend a bit of time getting her idling again. She now starts and idles like adream, having previously cleaned all the gunge out of the carb and fuel filter, replaced the cables from the battery, and replaced all the spark plugs.

We took her out for a spin and found her a bit lathargic. She runs OK in first and second gear, but an attempt to start off in second (normally fine) lead to an almost stall, and when I got up to third she wouldn't go any faster.

Has anyone got any thoughts on where to look next?
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  #2  
Old 08-07-12, 21:35
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Hanno Spoelstra Hanno Spoelstra is offline
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Does the ignition advance mechanism work properly? In my (limited) experience this could be one of the causes of the problem you describe.

H.
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  #3  
Old 08-07-12, 22:15
Bruce Parker (RIP) Bruce Parker (RIP) is offline
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A long shot, but what you described happened to me once. It turns out the problem was not fuel/electrical at all. For whatever reason (rust from sitting?) the parking brake (transfer case mounted, not the rear drum type) became too tight. At slow speeds in the low gears everything seemed normal but it got sluggish on slopes and in higher gears.

Quote:
Originally Posted by Lauren Child View Post
Blimey, I seem to be going from one thing to another on Dolly (FGT F22)

Today I managed to spend a bit of time getting her idling again. She now starts and idles like adream, having previously cleaned all the gunge out of the carb and fuel filter, replaced the cables from the battery, and replaced all the spark plugs.

We took her out for a spin and found her a bit lathargic. She runs OK in first and second gear, but an attempt to start off in second (normally fine) lead to an almost stall, and when I got up to third she wouldn't go any faster.

Has anyone got any thoughts on where to look next?
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  #4  
Old 08-07-12, 22:56
Lauren Child Lauren Child is offline
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Thanks for your help guys.

I'll take a look at the parking brake - it was my first thought in case its been stood for too long and got a bit stuck. I'll add some chocks to my shopping list.

What's involved in the advance mechanism? She's got an electronic ignition fitted by a previous owner, which should hopefully make a difference, but I've had *no* experience of ignition systems so that'll be something to learn.
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  #5  
Old 09-07-12, 00:31
Phil Waterman Phil Waterman is offline
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Default If you were here in the States I woud say gas

Hi Lauren

You mention that the truck had been sitting for a while, with my trucks here in the States and what they have done to the gas, I would stay the gas had gone flat or picked up nearly a full load of water that the ethanol has absorbed. Gas has gotten so problematic that I don't even start to look for causes of poor performance without getting a fresh tank of gas.

Do let us know what you find so we add the diagnostic tip to our lists.


Cheers Phil
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  #6  
Old 09-07-12, 22:49
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Hanno Spoelstra Hanno Spoelstra is offline
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Quote:
Originally Posted by Lauren Child View Post
What's involved in the advance mechanism? She's got an electronic ignition fitted by a previous owner, which should hopefully make a difference, but I've had *no* experience of ignition systems so that'll be something to learn.
I'm no expert either, but there is a mechanism which advances the ignition spark as the engine speed increases. If the mechanism does not work, the spark is not advanced resulting in a sluggish engine.
The electronic ignition cannot wander off like a mechanical one can, so it's probably not the cause of your problems - unless it's defective.

What happened / changed since it last ran fine?

H.
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  #7  
Old 10-07-12, 00:26
Comox Air Force Museum Comox Air Force Museum is offline
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Buy any chance did you put resister plugs in the engine. With a 6 volt ignition and resistor plugs, there's not enough fire left at the sparky end to do the job. How do I know, we just went through this same problem with our truck. Put solid core plugs back in it and all was well again!
Rob
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  #8  
Old 17-07-12, 22:35
Lauren Child Lauren Child is offline
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Thanks guys, I'll take a look.
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  #9  
Old 18-07-12, 11:24
motto motto is offline
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Installation of an electronic ignition kit will not alter the function of the centrifugal advance. The weights still cause the cam to move slightly clockwise in relation to the main shaft as revs increase. The only difference is the cam carries magnets instead of opening and closing points.

A timing light will tell you immediately if you have a problem with the advance.

David

Whoa! I just noticed that the vehicle in question is a Ford. All bets are off. Chevrolet, the only way to go!
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Last edited by motto; 18-07-12 at 11:30.
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