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Did I screw up my 3.0 rebuild?


SheepDog

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Sorry in advance for the longish post.

Last year I inherited a very very neglected 2004 3.0 Ranger with about 90k miles from my grandpa when he passed away. It had lots of problems including blown head gaskets and plugged cats. Fixed those issues with new rebuilt heads from Dover Cylinder Heads and a new exhaust. Engine ran fine for about 10k miles before I noticed a pretty severe oil leak from the rear of the engine, up top by the rear of the heads. Also noticed some abnormal black carbon buildup on the tail pipe. Pulled the valve covers and intake manifold to discover some of the valve guide seals were loose and traveling up and down on the valve stems. This was a confirmed issue when I pulled the spark plugs and noticed signs of excess oil and carbon in that cylinder. Also discovered the external oil leak was from the rear lower intake gasket, it was shredded beyond recognition and was where the oil appeared to be coming from.

Anyway, since I had some free time and a little money to burn, my brother talked me into pulling the entire engine and do a rebuild. We had never done a full rebuild before so we figured this was a pretty easy engine to learn on. Pulled the engine and put it on a stand. When moving the stand, the engine fell off!! It luckily hit the oil pan first and then the engine mount and drivers side exhaust manifold. No major damage done at least from what we could see. Pulled the engine apart and prepped it for new rings and cleaned up the pistons. The old rings and pistons were pretty sludged up and had a lot of carbon on the ring lands and piston skirts. Cleaned up the existing pistons and installed new OEM sized rings per the Haynes manual. Double checked to make sure they were installed correctly. We then took a 400 grit cylinder hone to the cylinders to rough them up for the new rings. This is where I think we messed up. The hatch marks we put in were way different than the factory marks. Ours ended up being more horizontal and much finer than the factory marks. The more we honed, the worse it got so we just got them all roughly equal and called it good. I also had trouble torquing all the head bolts on the motor since it was on the engine stand. I think we got them tight enough though.

Reinstalled the pistons with new bearings as well, new Fel-Pro gaskets and seals all around, torqued everything to repair manual specs, and reinstalled the motor. Put in some 5w20 oil and fired it up.

The problem:

The truck idled slightly rough, just barely enough to notice it but it was vibrating just a little bit. A constant stream of grayish white smoke was seen from the tailpipe. Kind of like the condensation you see from a normal engine on a cold day, but ours was just a little more dense and would not go away, even after the motor was warm. We took the truck to town, about 10 miles away. Noticed the smoke would disappear after a hard acceleration and would stay away as long as we kept driving it. As soon as we stopped at a light or stop sign and it idled for a few seconds, the same grey-white smoke would come right back. It only goes away and stays away after a hard acceleration. Let the truck sit and idle for about 30 mins and the thick smoke never went away. Never seemed to lose any coolant and there is absolutely no blow-by out the oil fill cap or the dipstick. The PCV system looked good and the intake manifold was dry and oil free. Manifold gaskets looked intact. Valve seals were still correctly installed.

Just today I checked the compression on the engine and got 150-155psi on all cylinders except number 6, which was at 140ish. Totally forgot to do a leak down test. Every spark plug had thick wet carbon on the end of the threads. These plugs were brand new and only had like an hour of run time on them. So I pulled the heads today and saw that all the pistons and chambers looked like they were glazed with a golden hue that I could wipe off with a rag. The combustion chambers near the valves were already starting to show thick carbon buildup. The head gaskets looked like they were in good shape.

The truck is currently in my garage with no heads on as I figure out what my next steps are.

I think we may have screwed up the honing on the cylinder walls so bad that now my rings aren't seating in, causing oil to burn in all the cylinders? Is it worth it to pull the motor and have a shop rework it or should I just buy a reman engine? Since the motor fell about 2 feet to the ground, I was worried about a crack or something as well. But all the cylinders look like they are burning oil so idk. Would a thicker oil help or allow the rings to seat? Will the rings ever seat with jacked up hatching? I'm at a loss right now. Our first rebuild attempt has been a failure lol. I'm half tempted to have it towed to a shop and new motor put in and calling it a day.
 


RonD

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The fall wouldn't be the issue, so don't worry about that

Cross hatching is done to HOLD oil on the cylinder walls
Yes, there is a "best angle" for the cross hatching but I don't think thats the issue either

Did you test the new ring's end gap in the honed cylinders before installing them?

Did you install new Valve stem seals in the heads?

The no oil burning on acceleration but on idle would point more to valve guide seals, i.e. with higher vacuum in intake(at idle) more oil can be sucked down the intake valve stems to be burned, on acceleration vacuum in intake drops so less oil

EDIT, I see you got new heads
also with 2004-2006 3.0l engines there was a TSB about Exhaust valve seats shifting/recessing, so new seats or new heads would be needed
This one wouldn't cause excessive oil burning
 
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SheepDog

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The new heads I got last year were reman pre-99 heads with the 8mm valves. When we pulled the heads for the rebuild I bought new 8mm seals and put them on. We tried 7mm seals first but they obviously wouldn't fit. I suppose its possible I put the new seals on wrong? They all looked uniformly seated and the stems moved freely.

We did not end gap the rings. They were supposedly "no file" rings and appeared to fit just fine upon install.
 

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