I will be pulling the head. Hopefully the piston is not shot. I will pull the valves and see if they suffered any damage. Might as well put valve seals in as well. Oil consumption has gone up slightly. I actually have to add a quart of oil in 10,000 miles, totally unacceptable. Cylinders look good with hone marks still visible.

Perry

 

A qt of oil in 10K miles isn't bad at all, especially since the NOACK % evaporation has gone UP, on a number of API/SN-GF-6 engine oil recipes. So if you like me had a number of your family fleet suddenly begin to consume oil when your brand choice SN-GF-6 went in back in 2011, maybe look up its NOACK % evaporation to see where it stands. If for example we have a 5 qt sump & use an oil with 15% evaporation NOACK, we could loose/use/consume 24oz in one oci due to evaporation alone!!!!
Probably a good idea to rework the top end while your there & while at it, also consider redoing the water pump, timing belt, idler pulley & tensioner.

 

Yeah it is normal to get some evaporation the first 1000 miles or so. I will definitely replace stem seals and most likely the timing belt. The water pump is the original and I may not replace it unless the bearings are rough. Worn out OEM stuff usually out lasts aftermarket crap from China. I will have to see what a new Motorcraft pump costs. I think it can be changed without removing the timing belt. It is still a pain though. I am going to look at the valves and not mess with them if they look good. Good engine work is hard to find these days. I hope I can remove the AC/power steering pump bracket without having to pull the pulley on the power steering pump again. That has to be the worst design flaw on the truck is having to remove the power steering pulley to remove the pump. I may consider slotting the holes in the bracket to fix that problem.

Perry

 

Here is a photo of the debris embedded in the piston.

 

Bummer, gives new meaning to being "screwed" doesn't it!!!!

 

Well the piston is cracked not where the screw head was but in a different place where the shaft of the screw was jammed between the piston and the head. Bores look new and head and valves look good. I will post pics soon. Looks like I need to pull the block and put in a new set of pistons. Might as well make a new engine out of it.

The screw was a stainless pan head sheet metal screw. How it got in there is a mystery. That screw was not part of the truck. If you have your upper intake off make real sure you don't have anything in there. There is no clearance in some places between the piston and the head. It is not a domed combustion chamber.

Perry

 

^+1 on keeping openings covered/plugged with shop rags, ect, when we have em opened up, because Murphy's Law is still in full effect!!!! But you get an Atta Boy for continuing on with a proper rework that'll likely make it good for another 20 years!!!!
Thanks for the good feedback & learning photos.

 

Here are more photos. Here is the Culprit. Pan head stainless sheet metal screw from my Airstream.



No damage to head.



Damage but no cracks.



Cracked edge most likely going down to first piston ring groove. This was the deal breaker.



Not much wear for 270k and Mobil 1 10w30.

 

If the piston hit the screw hard enough to crack it, then the damage may not be limited to the piston. If you start rebuilding the engine, then examine the rod and associated bearings for damage, too.

 

Took the valves out of the number 3 cylinder where the debris was. Intake valve looks fine. No debris damage. Exhaust valve is pitted from use. Compression was probably down even though it tested at 160 psi. The margin on the exhaust valve is .14 inch which seems a bit wide (WHAT IS THE SPEC ON THIS)? The seat looks smooth with no pits. Probably easiest to just lap in some new exhaust valves as opposed to grinding these pitted ones. Good machine shops are not easy to find then they charge out out the butt for crappy work. I replaced and lapped on my Eclipse exhaust valves with good results. Valve stems look brand new.

Perry

 

Here are some more pics.














Exhaust seats have receded into the head and gotten wider. They will need to be re-cut. Everything else looks new.

Perry

 

Just an update. The engine is out of the truck. Looks like I will be into it about $1000 in parts. I already have over $700 worth of stuff in my Rock Auto shopping cart. Crank is good but head needs some work. The question now is do I want to put $1000 into a $500 truck or would I be better off getting a newer truck to replace it. I have another car I am working on as well. The truck has no deep sentimental value. Time is the biggest factor.

Perry

 

Economically, you can repair month to month, year over year, and pay less than payments for something new. But.
Do you want to keep the truck for XX years to amortize a $1k investment? How long would you feel 'tied' to the thousand bucks, before you felt you'd gotten your moneys' worth?
I think I would be checking craigslist for a drop in used engine. If you were local, there's one for sale now for $400, and one for $350. With a bit of searching, you might find a decent engine that will last without trouble for as long as you want it to.
Your truck was well maintained, and that makes a difference in reliability and how well it runs. I still think you can find one that is in reasonable shape and save yourself a pile of dough and quite a bit of time. Unless you plan on keeping the truck until the wheels fall off, I would not put that much into it. The Lima will take a lot of abuse, and seems to last a long time (unless fed indigestible screws) without too much fuss. You might have been ok just removing the 'interference' part, and putting the head back on. No telling how long the piston has been cracked. From appearance it has been a while. The 'image' of the screw threads looks as if it has even gotten carboned up, and there are other spots I think the threads were impacted into the piston. I think it has been broken a while, and screw the head moved around for some reason, and started to make noise.
If you don't drive cross country, but drive locally, you know how its been maintained and how well it runs, so would have little loss if it died putting around town. Odds are in your favor.
Check c-list for used trucks that have body damage if you want to reduce the expense.
tom

 

Well money is not an issue. The time it would take to do it is more of an issue since I have way too many irons in the fire now. I might be better off selling it for parts and buying a used one with less than 100K miles on it. I have seen them for $2500-$3500. Yeah I could do a slop job and get it running but if I am going to do this I might as well do it right.

I have to put the front end back on my Eclipse, timing belt and water pump on the wife's legacy, work 40 hrs a week, run a sideline business keep up 3 acres and a house with a pool (Pain in the ***). This is if I don't overhaul the Ranger. Busted the AC hose on the Ranger as well.

Anyone want a project truck with a good body?


Perry