I have a 1985 f250 6.9 Diesel with many problems, if you could help that would be great. First of all it has alot of blow-by coming out of oil fill cap. Second, has white smoke coming out of tail pipe at idle and under a load. As of recently the smoke has turned black off and on(under load) and looks like a tire fire. Have already had to talk to a cop once. Third, a light knocking at idle and a loud one under a load. Any ideas would be greatly appriciated. Don't want to have to junk this truck.

 

Is the air filter clean ? Turbo ?

Also you may have a bad cdr valve and possibly a bad injector or two .

How many miles are on it ?

Does it use much oil ?

 

We just cleaned the air filter yesterday with no difference showing after driving it today. odometer reads 30207 rolling over once already. Yes, it's a turbo. i go through a gallon of oil in a week (not highway).

 

sounds kinda like a bad ip. had the same problem with mine changed the ip and it solved the smoking and the knocking.

as for the blow-by, i'd check the cdr valve. you could slow the oil consumption by adding a gal. of Lucas oil stabilizer that will thicken the oil a little and will take up some of the slack.

But hey if you want to junk it let me know I need some good parts

 

When you say you cleaned the air filter, are you running a K&N?

 

Hello to all. Well, here goes.

About a year ago I purchased a used '86 F-250 4x4 with a perfect body. I already had the same truck with a body that was rusted badly from living around the ocean. The engine in my original truck was doing well and I was going to switch engines to the latest truck. As it turns out my brothers son needed a truck to move and I have since not seen my truck again. LOL Soooo, I bought a Ford rebuilt and had it installed by a reputable independant. Along with the engine I replaced the clutch, pressure plate,TOB, pilot bearing, rebuilt transfer case, u-joints, starter, etc.

Now the problem.

I have been driving the truck for about 50 miles and looking for smoke, out of habit, to see how badly it was smoking. I noticed none until about 54 miles when all of a sudden I take off from a stop and see all this smoke coming out of the exaust. I have been driving this truck easy for the break-in. I have not gone over 50 mph.

I get home and take note of the idle being set too high for my experience. It is idleing at 950 rpm., so, I do the idle adjust and see the springs are in the wrong place. This was from the previous owner and not the independant. Finally, after getting the springs set, I get the idle down to 750 and it won't go any lower. The engine was just driven for 45 min. and it is warm and the solinoid is not engaged.

The next day I start the engine and there is a lot of smoke. More like fine dust actually, but, smoke none the less. Black and smoky. I take a little drive to see if it will clear when it warms, but, no luck. As a matter of fact, while I am taking a turn at an intersection the engine kills and makes it very hard to complete my turn and try to stop. Instead of stopping on the downhill I use compression to get going again. Starts right up. I let off the throttle and it kills again. I use the starter and it starts up again. Keeping a light throttle at the stops. I notice that it is not smoking anymore, but, it just kills at stops. I get to the flat and start to move to an area of safety to check it out. Now the idle is at 1100 and doesn't want to come down. I try a quick rev to make it unstick???? It goes to 1300 rpm. and I shut it down. I figure the springs broke or came off and I check, but, they are fine. Looking at the IP I notice that the idle adjustment screw is jammed into the IP body and is preventing the throttle from moving back to idle. I move the throttle lever to full open position and remove the idle adjust screw. I take the screw out completely by hand and release the lever. I try to move the throttle lever now and it is frozen. It will not move. I put some pressure on the lever and it moves, with some grinding feeling, about an inch. That inch of travel is working fine. I move it some more and finally get it to full range. Now I restart the engine and the idle is at 550 rpm. and the smoke is back. On acceleration it is smoky and going uphill it is smoky and on a flat it is still a little smoky and going down hill it is also smoky. My brother follows me and says it is black smoke and seems to be a lot.

What do you think?

Great site and thank you in advance. Lots of good brains here. -ED

 

First edsofish,
Welcome to FTE.

86 is a nice truck, I like mine just fine.

Sounds like the IP is trashed.
Do you have a warranty from Ford?

 

Thank you for the welcome.

Yes, there is a 2 year unlimited milage warranty on the engine and I will persue the outcome tomarrow morning. I will keep you informed as to the outcome.

Thanks for the quick response.

The best to all. More to come. -ED

 

Welcome to Ford Truck Enthusiasts blusparkz and edsofish.

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