Did I buy a problem? Fuel flutter

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Mar 31, 2007 | 04:59 PM

TomA92

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Did I buy a problem? Fuel flutter

I just bought a '86 F 250 4x4 with the 6.9 diesel. I checked it out real good and I believe the engine is in good shape. Oil looked good, good antifeeze, no blowby. When I took it for a ride it seemed to have a bit of a hessitation but seems to have good power. It blows some smoke when I get on it but cleans up if I back out of it. I drove it home in the dark last night and it seemed to pull the hills good but I was not able to check for smoke because it was dark. This morning it started right up and I let it warm up in the yard. It idles real nice with no miss. I noticed when I hold the throttle open at fairly high rpm it kind of flutters and smokes. I am sure it is a fuel related problem. The wife is picking up a fuel filter and I am going to try that before I go any farther. The manual says not to fill the new filter with diesel but to let the pump fill it. It seems to me that I should fill it with diesel before putting it on. Also where is the water separator? I have not found it yet but the light goes off. Does anyone think a fuel filter might fix it? It seems to me if it will blow smoke it is getting plenty of fuel.

Mar 31, 2007 | 06:57 PM

KJLYPW

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From: Powell River B.C.

I change my filter with the engine still a bit warm, half fill filter with additive of your choice, (helps IP and injectors with a super dose of lube) then top up with clean diesel, then spin on and tighten, my truck fires right up like nothing happened, no bleeding, no problems.
If you don't know when the injector o-rings and return lines were last done, you will want to do that, as they are known problem area for air intrusion, leading to hard starting etc, may be the source of flutter, and it is easy and cheap to do.
My truck is 93 so I don't know about the water seperator, lots of them have been removed as they were problems for air I believe, others will let you know!!
Good Luck

Mar 31, 2007 | 07:14 PM

bigredtruckmi

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From: Huntington Indiana

If the return lines are painted gray they are original and need to be replaced.

If you don't fill the fuel filter with fuel or additive (leaving air) It will take a lot of cranking on the engine to get it running properly. Don't crank more than 20 seconds as this will burn out the starter.

Mar 31, 2007 | 08:28 PM

brownieboy525

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From: south jersey

the reason that they tell you not to fill the filter is because the fuel that you dump into it will not be filtered so just make sure you use clean fuel or an additive i always fill mine with diesel klean.

Mar 31, 2007 | 08:37 PM

PLC7.3

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From: Manitoba

Only fill the filter via the outer ring of holes, it then will be filtered....... Fill the filter to within 1/2" of the top if you can........

Mar 31, 2007 | 09:47 PM

TomA92

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Thanks guys. I changed the filter, I had to crank it over quite a bit but it started. The tach is not working and I am not real familiar with this engine. I think maybe the flutter is running against the governor. I took it for a ride and it seems to run good and not much smoke unless I tromp on it.

Mar 31, 2007 | 10:01 PM

PLC7.3

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From: Manitoba

Whatcha mean......

Quote:

I think maybe the flutter is running against the governor

Exactly what do you mean.......if your depressing the pedal to max rpm then it will smoke and pop even backfire....... the IP is shutting of the fuel, then turning it back on when rpm is lowered.