Hi guys,
First off this is my first post on this site and I hope that someone out there could give me some sound advice! I recently bought a 96 F250 with 47,000 miles. The truck supposedly had sat for a minimum of 2yrs. The truck ran like crap when I first got it, but it was expected to need about a grand worth of work (I got off much cheaper by doing all the labor myself!) However, there is one problem that is killing me and I cannot seem to figure out what to do because everyone I know has told me diferent things.

Here's the problems...1. the truck seems to have a ticking sound from deeper in the engine than just the valvetrain. 2. my oil pressure gauge spatters back and forth while idling, goes completely low when turning slow and the truck sometimes stalls when turning slowly in reverse or drive. When sitting at a light the gauge spatters, when i step on it the guage returns back to normal range. 3. I have serious blow by to the point where I have oil coming out of my air box. 4. engine is consuming about a quart of oil when I use it solid for a day. 5. oil buring out through the exhause, smoke from exhaust and occasional spatters of oil from the tailpipes. 6. Lastly, the truck cannot climb hills and just seems to not have any power.

Here is what I have done so far... I have changed the oil several times in the past few weeks, every time there seems to be some sludge that is loosening up and coming out. I have replaced both air filters only to have them get full of oil again due to the blow by. every time I check my dipstick there is never an accurate reading, sometimes the oil is half way up the stick and sometimes it is scatterd. At one point, there was a creamy bubbly looking substance on my dipsitck and oil cap. I have changed the pcv valve.

here is what I think...The truck sat for years, there was crap that sat and possibly solidified in the engine, Im thinking that this sludge is just holding my engine back from its true power. I plan on replacing my oil pan soon bacause my current one was rusted out and patched. I hope that by flushing the system, replacing the pan and filling with heavier weight oil that my problem will be solved. but I have a feeling that this will not solve the problems.

SO...what sould i look for when i take the oil pan out? should i replace the pump? Do I need to get into the valvetrain? if so, I need some direction because I have never worked on the 351! Do all my symptoms sound normal for my situation? Does it seem all interrelated or could there be other things than just my hunch of the sludgy oil being the cause? Im sorry about the legnth but I just wanted to be as detailed as possible. Any info or referrals will help, Thanks.

 

Many folks over at the oil guy site swear by Auto Rx. I am trying it now in my truck. I am not convinced, but not done with the program either. You have nothing to lose but the cost of the product. It's supposed to dissolve the sludge with natural esters (esters are Group V synthetic) that are unique in the Auto Rx formulation. Call them on the phone and talk to Frank. The website is Auto-Rx.com. If you do it, gonna take you about 7000 miles to complete the double treatment that it sounds like you need. Just be sure to follow the instructions to the letter.

Other than that, when you changed the PCV valve did you also check that the PCV hoses are not clogged?

How about a plugged cat possibility?

 

You need to get a mechanical oil pressure gauge and see what your oil pressure is. The stock gauges can be so far off its not even funny. Second, drop the pan too see how much sludge is in there. Dont bother replacing it if you want to save money, no reason to. While the pan is off carefully examine the crank, rods, oil pump pickup tube etc. Check to see if the pickup tube is clogged. The oil pressure issue sounds like a gauge problem too me. Also where is this ticking coming from exactly? Valvtrains make a tickish noise while the rotation assembly will make a knocking noise when loose.

 

That sounds like a stuck ring / or rings from the sitting. I would suspect that some water got in there and rusted 'em, possibly pitting the cylinder wall. The knock is probably piston slap resulting from the stuck rings. You'll probably need a rebuild.

That said, some 15w40 diesel rated oils are good at freeing stuck rings, I suggest you try one. Look for Mystik JT-8, Shell Rotella T, or Chevron Delo.

 

Thanks for the info so far. I plan on replacing the oil pan tomorrow. One of the reasons im replaicing it and not re-using it is because there are 4 or 5 spots (some pretty big) where the previous owner patched them. I want to just start fresh with a new pan. Im not too excited to get in there though because Im not sure what i'll find! Is there any thing else that I should keep an eye out for when in there?

As for the ticking noise, it is a low end tick and sounds louder on the right side of the motor. I also agree that since it sat soo long that the pistons are rotting out and the rings could be all over the place. I am not up for a rebuild so I hope that the noise settles down after the oil cleaning.

Also, since i am burning so much oil I have went with a heavier weight oil recently. Today I added 1 1/2 quarts of 15W40 and after 5 minutes or so the engine quieted right down. but after a days driving, she was rattling like a when I do the oil flush and fill, I was thinking of using 20W50. Is this reccomended for heavy driving?

finally, say I can fix the oil pressure problem and can keep the engine running clean but the ticking noise stays, Is it okay to still drive it? Again, I am not up for a rebuild, I just bought this truck and allready have sunk a good amout of time and money into it. I Would rather sell it for a new truck than rebuild it. Again, any info will help...thanks!

 

Ok, time to break out an old trick. Seafoam. That's a brand of engine cleaner stuff you can buy at the parts store. What you do with this stuff is you let it suck up a vacuum line with the engine running. It goes into the intake and cleans off the piston tops and rings. It's good for freeing stuck rings and cleaning off carbon.

You probably dont need a full rebuild, you could probably get by with re-ringing the pistons. Better yet, you could remove the piston / rod assemblies and manually free up the rings, lube 'em up good, and stick 'em back in.

 

Remove a valve cover and inspect for sludge up top. Sounds like a lack of proper maintenance and possibly in need of an overhaul. The mileage seems awfully low for the age of the truck, even if it did set for 2 years.

 

Drain the oil, leave the old filter on, add 4 qts ATF, let idle for 15 - 20 minutes, drain, change filter and put in new oil. I would stay away from the 20WXX just yet. May want to do the Rotella thing.

 

47,000 miles, no way. Multiple patched holes in the oil pan. Oil out of the exhaust pipe. One time I bought a truck that had 50,000 miles on it and had never had the oil changed. Nothing could be done to save that motor either and it did not have any of these problems.

First, see if the odometer has been altered and then "leak" the motor.

If your into saving money, do not waste time on this motor. Get serious.

 

Only thing I can think of for "leak" the motor is you can run it with the pan off (and the pickup in a large oil reservoir) and observe if too much oil is leaking out the bearings, but there is an easier way if you have a good pressure gauge.

I still say try Auto Rx. Nothing to lose, but the product cost. This stuff is raved about at the oil guy site and your engine is a perfect testbed for whether AutoRx can handle the tough jobs.

 

If the oil looks like a milky sludge there are bigger problems even than sticking rings. There is water in the oil if you see foamy chocolate milk oil.

The oil gauge can be explained. It's on an oil pressure switch. With the switch on it triggers to around halfway, with it off it drops to the bottom. It triggers around 8psi. If the gauge is at the bottom, it's below 8. If it's in the middle it's above 8. If it's fluttering it's basically right at 8 and pulsing from the oil pump causes it to switch on and off.

The bottom line is that if the oil pressure is that low the motor is in horrible shape and you can try snake oil but it's probably too far gone to help it.

 

I'm thinking 147,000 miles, just an opinion... And not an educated one.

Just for grins, if it has been altered, it is a Federal infraction....

 

The 96 has a digital speedo that doesnt roll over, But possibly was unhooked for several years, but if it has an automatic it wouldnt shift right. I would say lack of maintance. Change the pcv valve and run some Delo or delvac 15w40 for a while. I would say the oil pressure gauge is right if its going to zero at low rpms.

 

From the discription of the thread, the engine has all the symptoms of high mileage, poor maintenace, and is just worn out. You can flush the engine and change oil all day long, but it won't correct worn parts. If anything, it will only make matters worse. IMO

 

Seafoam it. Use the whole can, too. Half through the brake booster vacuum line, the other half into the oil. Let it suck it up and then kill the engine, let it sit for a while - and then when you start it up again O_O. Change that oil afterwards though...go with something like Rotella 15W40 that cleans good. If its savable..this is how it's gonna be saved. Otherwise...better get a junkyard motor to swap in.