BiodieselLuke
Registered User
I picked up a 94 factory turbo 250 4x for a grand a few months ago. It has a ford rebuild on the trans and as far as I can tell, no love anywhere else. Straight body and whatnot, but the cooling system has been neglected although it has a new radiator. I took the cap off and the coolant was more pooh brown than anything else. I did a pressure check of the cooling system and it dropped from 18 to 17 pounds over about a half an hour. Has since been flushed and coolant replaced.
It has a loud knock at idle that sometimes goes away, however it seems to be more consistent now that it is cold out.
I have the chuffing sounds through the exhaust and a pretty good misfire when I first start it in the morning. The misfiring is accompanied by a bunch of light colored smoke, but only in puffs, coinciding with the misfiring cylinder. If I fire off the truck and immediately take off, putting a load on the engine, the smoke clears up right away. The glow plugs are all good except the 2 under the turbo which I have yet to test. If I take off the oil fill cap, at any temperature, I have a bit of blow-by on only the one cylinder, which one I do not know. i'm hoping that I have not cavitated, as the cooling system holds pressure pretty well.
Question: could a simple valve guide issue be leaking cylinder pressure into the crankcase and out the oil fill cap? I'm hoping to have some heads rebuilt off of a spare motor and change them out in a day. I don't want to spend the cash to rebuild the heads and find out I have bigger issues. If I have to rebuild the motor I might want to go ahead and put a cummins in although I really like the peppiness of this motor compared to the DI fords and dodges of my past.
PS, I know I need to do a leak down and/or compression test, but I just don't have the tools or money at this time for that.
Any help or insight is appreciated
Luke
It has a loud knock at idle that sometimes goes away, however it seems to be more consistent now that it is cold out.
I have the chuffing sounds through the exhaust and a pretty good misfire when I first start it in the morning. The misfiring is accompanied by a bunch of light colored smoke, but only in puffs, coinciding with the misfiring cylinder. If I fire off the truck and immediately take off, putting a load on the engine, the smoke clears up right away. The glow plugs are all good except the 2 under the turbo which I have yet to test. If I take off the oil fill cap, at any temperature, I have a bit of blow-by on only the one cylinder, which one I do not know. i'm hoping that I have not cavitated, as the cooling system holds pressure pretty well.
Question: could a simple valve guide issue be leaking cylinder pressure into the crankcase and out the oil fill cap? I'm hoping to have some heads rebuilt off of a spare motor and change them out in a day. I don't want to spend the cash to rebuild the heads and find out I have bigger issues. If I have to rebuild the motor I might want to go ahead and put a cummins in although I really like the peppiness of this motor compared to the DI fords and dodges of my past.
PS, I know I need to do a leak down and/or compression test, but I just don't have the tools or money at this time for that.
Any help or insight is appreciated
Luke
