Tom, you lost me. I am coming up with about 11:1 static compression from his cranking compression. if there was a thin steel head gasket on it there might be a chance of lowering compression, a long with taking about 5-6 cc off the dome, that was the most i could take off my JE pistons, not sure about auto tech pistons
So what do we think failed? We have: - smoking while running, oil fouled #2 plug. (could be broken ring, bad valve guide) - Cylinder didn't hold oil (location of ring gap(s)?), but has good compression. - Clean piston and combustion chamber on #2. (excess fuel or water). Contradicts oil fouling. - Rod bearing damaged but not horrible. (received contaminated oil) - Metal fragments in oil and oil filter. Are they on a magnet in filter? The metal fragments look large. If they're magnetic, it's not bearing material. Trashed cam lobe? or something was rubbing but what? Did crank or cam eat into the block? Timing chain, oil pump, or fuel pump damage? I would guess a broken ring on #2 and possibly other unrelated damage such as fuel/water getting into #2, and something else making the metal shavings which damaged the bearing. Overall I'm seeing unrelated symptoms which don't add up. What do you guys think? I'm kinda perplexed.
yes your right to much metal just from bearings .one thing for sure to much compression for the street. yes broken ring maybe from detonation or metal in oil, bad boring or honing job in that cylinder ?. yes lots of metal from some where, cam and lifters would be first thought but was it running bad and missing ?? . piston specs from auto tech would be nice pin height and dome size, deck height ?. was there a steel shim head gasket ??
All the metal is certainly questionable, but from where/what??? Wasn't a broken ring, as evidenced in video, when engine was taken apart at 3:43 in the video, something dropped on the floor which I think was the bearing falling out of the rod because it wasn't in the rod tight enough from being pounded by maybe unheard detonation??? AND, why did the oil disappear in ONLY #2 cylinder??? More questions. Doesn't seem possible that all the engines Dave has built that he was so sloppy as to have so much debris in his work. Who knows??? All we know is that Joe has to get this done all over again on his dime. If you watch the video some of these questions can be answered. On the compression results. The way it was explained to myself is you take atmospheric pressure, which is 14.7, & divided it into the compression pressure & the result is compression ratio. I could be more than likely wrong, or so in this instance, does seem so. Joe, do you have another way to figure it out WITHOUT all the specs??? Tom T.
i was so interested in the piston and head gasket specs was hoping he could work with the old pistons and not having to buy new pistons. Tom i read about your formula a little and some wrote it really don't work most of time. I just kept plugging in static compression ratio until I got to 217 cranking compression and came out to about 11:1
A few answers: Head gaskets were Best Head Gaskets, at least that is what I was told. I'm waiting for more answers once the new machine shop is able to evaluate the Nailhead. I hired the mechanic under the expectation we would find a broken piston ring, and voila, the engine would go right back together. When he found what he described as foreign object debris in the oil pan and the bearing the way it was, he recommended a full stop, and to contact my builder, which I did. You can see by the video the rest of that story how that ended. That item that dropped from the cylinder was indeed half of a bearing. There is also some dark marking in the piston bore, again we are deferring to the machine shop's evaluation. Engine was never running bad or missing. That's something I often opined to the builder; that thing ran great, except for the smoking. As far as putting the engine together, the bottom end will be up to the machine shop. At least at this point I'll be able to see all the internals.
Is it possible that he didn't offset all of the ring gaps on that piston. If he lined them all up, and they were at the bottom of the bore, you'd see that kind of leakage and a ton of oil burning.
Piston rings have a tendency to rotate on their own while running. I have never taken any engine apart where the rings were where I put them initially. I'm sure they rotate to where they will finally set. Maybe they stay there in the position or continue to rotate I don't know, but that could be the reason oil was lost in that one #2 cylinder. Even though the oil rings should take care of the oil control. Tom T.
Does his shop have others doing the work? I once unwrapped a 322 that was supposed to be assembly clean and was full of grit and metal from machining. On a friend's 401 sand was found in the oil galley after it destructed after 5 minutes running...apparently sabotaged by disgruntled employee
Dave is making things worse, mistakes happen could be all his fault, part his fault or not his fault at all, it doesn't matter now just have to move on, but hiding when he could shed a lot of light of what might or why it happen, plus he knows all the machine work and specs of the motor. he could be helping Joe a lot one way or another. i don't get why he would say it was going to smoke at first, rings are seated with in 50 miles not 2000 miles was there already something going on with the motor.
The engine rebuilder I used does indeed sub-out what I believe to be most of the machine work. I don't know where the line of demarcation is, but I know for the sure the builder was not doing the machine work.
Everyone I do the only thing shipped out is the crank UNLESS it just needs to be polished, then done in house. ALL machining done on premises. Head work, small porting work, otherwise will get shipped to Ca. Boring, honing with a torque plate, cleaning the coolant passages in the block with muriatic acid IF nec. on & on etc. etc. etc. Much time & MANY HOURS as anyone who has done this can attest. Tom T.
you would think metal in the coolant would be from left over machine work most likely, i know the water pump could be hitting the timing cover but not likely.
This is the "dark marking in the cylinder bore" I referred to above that the mechanic also had concerns.
Joe, I think he's talking about the wear mark from top to bottom of cylinder. Lack of lubrication??? Not enough oil being slung around??? Tom T.
This engine needs a proper teardown and post mortem report. Clearly there was too much trash in the engine, both oil side and water side. But we are only getting random glimpses of information. (although, it really does not matter what we get, Joe needs the facts as his current builder is the only one who can provide him a true assessment) And without any input from Dave, it makes it very frustrating to understand, as well as considerable expense of nearly $8 grand and be at this point and looking at another rebuild. Even if most parts can be re-used, the labor to do it right and possibly machine work to correct, is a kick in the bruised back pocket.
