It's possible, but also could be caused by bad valve guides. What do the undersides of the valves look like? If you pull the springs you can check for wobble in the valve stem. As far as the rings are concerned, you'll know once you pull the pistons.
Its bored .030 already so im not going to rebuild it. Dropped off the heads this morning and the valve guides are bad. Im going to have the heads reworked with hardened seats, new springs and guides. Bolt her back together and be done. Will probably pull this motor this fall and replace with a roller 302 crate engine. Im getting the funds together for the roller engine, im just not there yet. BUT i cant just let her sit, she deserves to be driven.
I'd finance the engine you want now rather than build one, then another engine.
Alternately, go get a junkyard longblock (look for one you can hear run) for $300 and run that until you can afford your crate. Then sell the junkyard engine for $300 on craigslist.
Just my $0.02
Edit: I read your post wrong. You're just having your heads rebuilt. Carry-on.
Last edited by 88cougargt; 01-29-2013 at 12:19 PM.
Decided since it was down for a couple of weeks while the heads are getting redone, I change the timing chain, water pump and oil pan gaskets.
All back together and some fresh paint.
Was it blowing blue smoke?
If so, was it when you first cranked it in the morning/first time for the day and then clear up? That's a sign of valve guides and seals. Oil leaks down into cylinder while sitting.
If it smokes all the time, or really bad after idling a few moments, that's a sign of bad rings.
__________________
1995 GT convertible - Laser Red
1995 GT convertible - Black (Son's ride)
1966 GT Fastback under restoration- Code T Red
with White LeMans stripes.
Was it blowing blue smoke?
If so, was it when you first cranked it in the morning/first time for the day and then clear up? That's a sign of valve guides and seals. Oil leaks down into cylinder while sitting.
If it smokes all the time, or really bad after idling a few moments, that's a sign of bad rings.
ScottsGT, I would get blue smoke in the morning that smelled like oil was burning. It was fine for the rest of the day. No matter what time it would smoke white very lightly, I had a coolant leak on the water pump and a bad head gasket on number 5 cylinder. So yes tool heads off and had bad valve seals. Other than that everything looks good.
Did you run a compression test before removing the heads? It looks like you can still see a crosshatch pattern on the cylinder walls. Looks to me like your bottom end is still good to go.
Did you run a compression test before removing the heads? It looks like you can still see a crosshatch pattern on the cylinder walls. Looks to me like your bottom end is still good to go.
No I wish had though. When replacing the oil pan gasket, the bottom end looked good, not sure if the head work was just done poorly when it was rebuilt.
Sounds like you did the fix with the valve guides. Keep us up to date on this and let us know how it turns out.
__________________
1995 GT convertible - Laser Red
1995 GT convertible - Black (Son's ride)
1966 GT Fastback under restoration- Code T Red
with White LeMans stripes.
My cylinders looked like yours generally speaking. Mine was machined years ago, but only had about 20,000 miles on it when I last parked it. I am now restoring the car (body shop does body - I do mechinicals) and here are a few observations from my engine:
The piston tops were incredibly gunked with carbon deposits, down through the second (middle ring). I removed the rings and soaked each piston in a gallon can of solvent from NAPA. I then brush cleaned all ring grooves, piston tops and accessible piston bottom surfaces with a soft nylon tooth brush. I replaced all the rings.
The pistons had a limited amount of observable wear on the skirt just below the oil ring.
The cylinder walls still looked freshly honed with a very distinct cross hatch pattern (similar to yours). The top ridge of each cylinder also had a similar amount of carbon build up. I removed it with solvent before removing the pistons. There is no discernible wear ridge.
I had the heads reworked with hardened valve seats. The shop told me that the previous machine shop had too tight a clearance in many of the valve stems. I got all new valves and valve stems.
My push rods had weird rings worn on them like yours, I replaced them.
Visual inspection of rod and crank journals revealed no wear. Plastigage revealed no measurable (for the method used) taper or wear outside of limits. In fact, I tested several of the journals, all were similar and indicated no wear.
The rod and main bearings had the zinc finish worn unevenly. The wear did not appear uniform around the circumference of the bearing but occurred at the top and bottom position of the bearings. I replaced main and rod bearings.
I am replacing all seals which was my original mission anyway since the engine sat for so long without running. My compressions before tear-down were all around 150 psi. The engine did not smoke or knock when I last ran it 8 years ago.
I can't explain the unusual wear on the push rods. I can understand the non uniform wear on the rod and crank bearings as the forces of the running engine are not uniform around bearing surface but linear along the piston axis which I think would cause wear to occur on the bearing surfaces at the top and bottom of the rod journal bearings. I think (recall) the observable main bearing wear was aligned top to bottom as viewed from upright engine orientation.
While I am in there (project still underway) I cleaned the water passages, rebuilt the water pump, replaced freeze plugs and all electrical stuff.
Even though parts of your engine appear to have been machined lately, it is worth checking clearances. A street engine has a lot more tolerance to wear than a high performance engine meaning that machine shop mistakes may not become manifest for a long, long time. If you have access to the last machine shop, I would see if the engine was balanced while in for machining. It seams that is a forgotten step in budget rebuilds.
Another observation, the water passages look very clean. I don't know where someone say the 0.060 over pistons so I can't tell that, but you said it was bored 0.030 over. All that points to a very serviceable engine. What is the date code on your block?
Ok got heads back, new hardened seats, springs, valve guides and new valves. Got it all back together today and fired her up and she is running great. No smoke on start up or while running. She got new hipo manifolds and dual exhaust while she was down. Got to finish installing the exhaust tomorrow.
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Help diagnose piston problems with pics
