Oh, and the presence of metal shavings in the tranny fluid is not necessarily proof of a bad tranny. There were shavings in the Lexus I drive. Its tranny is fine. Shavings are expected, this is why there are magnets on the bottom of the tranny oil pan… to catch them and get them out of circulation so that they don’t cause additional damage.
So where is the sign of irreversible damage on the unit once out of car?
Below is an answer I got from yahoo answers. It differentiates shavings from silvery sludge. I had silvery sludge. Read below:
Shavings, or silvery sludge? Silvery mud is normal. Granular metal, chunks or small metal shavings, or coarse filings, are no good! Something went very wrong to make those. Automatic transmissions work by having the fluid compress a packet of clutches together against some metal discs, for each gear (or sometimes pairs of gears in some designs). The clutches are made of a friction material, and bear against steel plates, when hydraulic pressure is applied by the valve body. Very fine metal dust is the normal wear debris from those clutch packs against those steel discs. There will also be ground up friction material in the fluid too. The clutch material can be a grey or brown color to a brownish red color, depending on who made them and when. High performance racing clutches can be a terracotta brick red color. The filter will filter a lot of that out. Maybe a teaspoon of silvery sludge is acceptable. Take a larger more powerful magnet, wrap it in a white plastic grocery bag, and see how much of the silvery sludge is metal, and how much is congealed fluid (oil). If the fluid is old, and nasty it can make the metal content seem like more than it is. Those discs in the transmission wear just like brake rotors, brake drums and manual clutches, and those all work with friction material on s steel plate or drum. The automatic transmission has to recirculate that worn metal through a closed recirculating system, so a magnet is used to keep the metal from wearing out the parts prematurely. Shavings or coarse filings? NO! Super fine powder dust in the oil, that looks live silvery grey mud? That is normal.
Here is the book from ATSG. https://www.atsg.us/atsg/manual-download-1/gf4a-el.html
You asked, my opinion I would rebuild it. But that’s me. I rebuilt my wife’s engine because I was pulling the tranny & rebuilding it. Did it need it? Not likely but who is to say it wouldn’t crap out soon after. I did it for insurance, incase ya. I did all that work to ensure that I had a new driveline with a known history.
No knocking of opinions here. I have mine. They get knocked. I don’t care.
And rebuilding is nice from the history standpoint that you share, but it is also risky in that the tranny may be fine ans set to go another 200k. Japs are famous for that, you know. Once I muck with it, well, it could be set to go all the way to Monetary, then back by tow… lol…
So how can we know for sure? What testing can we do? Where is that expert who can look and know for sure?
BTW, I discovered that the single head gasket I have is actually two steel plates congealed together in tar like black sealant material. Thought I might get that straight in case anyone notices…
I dont want to take away from the transmission question, but here is another question of particular importance:
-How do I remove the lapping compound from the heads fully once lapped? Water? Parts wash? Diesel cleaner? Air tool? All of the above?? Anyone have tried and true method?
If you are going to crack open the tranny, I’d advise you make sure you have FACTORY service manual. It will have the dimensions and alignments needed and backlash tolerances AND what tools such as dial indicators and poitioning to take reading. (Same issues for rebuilding a differential gear alignment and spacing is critical for wear on these. I personally haven’t done either but after reading the manuals … beyond changing a gasket or seal realized more to it than knew or wanted to try. Also been fortunate only one trans failure - 1959 Ford and just did a junk yard swap … I can honestly say lasted as long as I owned it or should say totalled it.) 115k isn’t much on a modren car.
Yeah, after thinking about it a while, I am leaning toward the old refill and stick it in the car method. It did not have shavings. It had sludge. Maybe it’ll be OK. I think we will find out soon.
And here is a video of today’s adventure: reinstalling valves. I cleaned the lapping compound using parts wash, a bazillion paper towels, spray cleaner, air gun, and one spell from nearby witch doctor… But nothing would get those springs to stick on those valve stems without some help from above…
Let’s hope for Zoom Zoom and not Mooz Mooz. You DID put the oring on the torque convertor rightwise and not backward, right? 
I vote for Zoom Zoom as well.
Here is the latest update I have, in video form:
How did the cams rotate once you got them all tightened back down? Timing look right?
I mostly just wanna know since I helped get them aligned. I now have a pride issue with seeing this car running again. 
I am glad to have another maker who shares my pride issue with this Mazda. I hope it plays out to the good for us. I believe that it willl But of course, this depends on my remaining vigilant, crossing my i’s and dotting my t’s. Vigilant!.. lol… There can be no silly blunders!
Here is a video that shows current progress and what remains to get this engine in the Mazda and try her out…
Progress resumes after four day tooling adjustment. In this video, I show the status of the car when I removed it from the lift on Wed 8-31-16 at noon. I was able to resume forward progress on this project on Sunday 8-4-16 late in afternoon. Labor day tool sale helped a ton. Lots of odds and ends remaining, but can clearly see the light at the end of the tunnel. I am happy to be able to work diligently at a comfortable pace, and not be concerned that I might be in the way of another project in auto. The remaining work needs to be done correctly, and I need to check it all carefully. I would like to take care to avoid rookie mistake here. I wont know till the end, but I think if I pay close attention to detail here now, I will be rewarded with a very nicely running Jap sport sedan. Yessir!!
Once things are assembled once again, and I fill the fluids once more, I plan to do a compression test to sanity check the work. What other checks do experts feel make sense prior to committing to ignition?
Oh, and I plan to use this bay to do some knock sensor/air intake work on Lexus. After that, this bay and tools will hang around for a while. So it is reasonably equipped now, still needs some stuff. But could be used for monetized work. If this information piqued your interests, lets talk. I’d love to give back to those who helped me so much with my monster project.
More progress on thw Mazda. I replaced most of the front suspension gear since I had to put in new front axles anyways (cv boots). So while this slows me down in starting thw engine, I can’t drive the car without axles. So I took the time here.
Dusting off this old thread, as it is still relevant to me right now. I have a whole lot more footage detailing what happened with the Mazda. I don’t have time to clean it an display it right now, but I will post it for all to see.
But here are descriptive results, and they are interesting ideed:
*Upon reassembly, I had to fix numerous leaks before I could run the vehicle for any span of time. Of particular concern was an old leak around the oil filter assembly. Try as I did, I simply was unable to seal this with the new felpro gasket I bought from Oreilly’s (I tried 2 of them). Ultimately, I bought a roll of thick gasket paper from Oreilly’s for about $15. I took one of the gaskets, placed it on a piece of the thick gasket paper, and cut out a thick gasket using exacto knife. This stopped all leaking immediately upon installation.
*The engine sounded GREAT, just like a brand new Mazda off the line in Japan, when I finally was able to start it. It smelled all sorts of funny and blew off various shades of smoke initially, as I figure it had all sorts of grime I had smudged on the headers, and anything in those cylinders got cooked. But the smoke stopped after a bit, making me feel comfortable for a test drive.
*The transmission did not want to shift at first. I have to fiddle with cabling before it started operating properly. But once I got this worked out, the transmission that sat on a palate for weeks covered in rust and slime now performs flawlessly. It has new fluid and filter, and now connects to a new radiator. The transmission shifts smoothly and solidly, and exhibits no symptom of any sort of trouble now. It runs as I would expect for a new car. What a relief!
*I had problems cooling the engine initially. After trying many different things, I got the fluid temp to level out at thermostat trip point. Once I saw this, I took the car around the block. It overheated. I replaced a bunch of hoses to make sure I had good flow. Ensured no kinks in any hose anywhere. Still, overheats upon 1/4 drive, every time. I finally decided that problem could be corrosion blocking radiator since car sat up in its history. Installed new radiator. This fixed all overheating problems. Then jI had a problem where the transmission fluid radiator fitting leaked. I had to construct one from parts from Home Depot. After about 10 tightening events, I finally patched that leak. Cheap radiator from Ebay=good radiator, lousy transmission fluid fitting.
*I drove car for 300-400 miles. It did OK, engine sounds great, however I noticed that the idle hunts. It ranges from 700-1100 RPM. I fiddled with sensors, and watched OBD scanner a bunch, but could not seem to solve this one. But I got my best clue when I noticed after driving some 5 miles that when I disengaged from drive to park, the exhaust would let out moderate to mild amount of white smoke. Then it occurred to me that probably my head gaskets are leaking. I surmised that it probably did not seat properly, and all the overheating at first due to radiator problems did not help. But most importantly, I did not do a great job resurfacing the heads. There was material remaining on them when I put in new head gaskets. I watched a video of man who makes his money resurfacing heads using block and sandpaper, and then he preaches as part of his lesson. My heads looked nothing like what his did when he was finished.
Then I read multiple articles concerning head flatness and seating of head gaskets. They pointed out that so much as a single overheating event is catastrophic especially for aluminum heads and block with double steel gaskets. Hmmmm.
The most common failure mode is hot gasses from cylinders getting into the coolant. Heads MUST be resurfaced to perfection prior to installing new head gasket. I did not come close to doing this. In my case, we expect that the failure mode for previous engine was that fluid got into cylinder, hydrolock, then bent rod upon running. The point of wekness where the coolant/water entered the cylinder is probably not fixed.
Now I have not bent a rod in the new engine. I ran it some, and it never sat up allowing a lot of fluid into the cylinder. However, I can see that it is not sealing well, so I have taken things apart again, at home this time, and am working to get heads resurfaced right now. I will get videos posted soon.
Thank you to all who contributed their time and help pointing me in the right direction. I am paying for my sin of not listening by having to take the time to remove the heads a second time. They will be flat as all get out, perfectly clean and resurfaced when I reinstall this time. I may be wrong, but I bet this fixes the idle hunt as well. I think hot gasses escaping the cylinders cant be a good thing for stable idling…
I would like to query the experts, as this is the primary reason I was hesitant to resurface the heads (sand them down well) in the first place:
I am concerned about valve clearance. How to I ensure that I will have valve clearance for this non-interference Mazda KL-ZE 2.5 L V6? The engine has HLAs, all of which I cleaned and oiled. I personally did a light lapping job on the valves and they seated quite nicely when done.
I imagine that I will need to take off possibly a couple millimeters of material on the bottom of my heads to restore appropriate flatness at the tricky points. If I find afterward that my valve contact the pistons, how would I adjust the clearance?
Now that I have looked at things, I have realized the answer to the question about valve clearance. The valves remain closed during most of the engine cycle. When closed, they are drawn upward to the seat, and they are all clearly above the plane coincident with the optimally perfectly flat surface at bottom of the head.
There are holes for the cylinders, obviously, in the bottom of the head, and a bunch of smaller holes all over the place that allow for the flow of coolant and oil as these fluids propagate through the engine. There are also psuedo-holes, as I will call them, at various points towards the extremities of this optimally flat surface at the bottom of each head. These psuedo-holes are not complete holes. Instead, they are ‘filled’ to a certain level, as one might call it if you flip the head upside down. The ‘fill’ point shows the mechanic the level which is the level required for the motion of the valves. If a knucklehead shade-tree mechanic, such as myself, were to remove aluminum from the bottom of these heads such that the optimally flat surface were to move beyond the fill point of the psuedo holes, then the valves have the potential to come in contact with surfaces such as pistons and what not. This knucklehead shadetree mechanic surmises that this is probably very bad.
So, tell you what, I will simply not remove aluminum from the bottom of the heads beyond this designated psuedo hole fill point.
Thank you for following up! I always love to hear about how things have gone for folks.
Sorry to hear you’re still having problems, but the silver lining is: more chance to learn!
Was this that video? https://www.youtube.com/watch?v=HyKN52HD6RU
He makes good points, but is not a professional.
That aside, it’s worth watching for the bits that ARE good.
It’s even done using a cylinder head much like yours (I think).
I have to ask: have you checked the camshaft journals for being aligned? One needs to be certain the cam journals are in line before one removes material from the bottom of the head to flatten it, as if the cam journals are not in line, THAT needs to be addressed first. This is generally done by retaining the services of a machine shop with a jig and an oven. It gets bolted to the jig, baked @ 425F, or so, for hours, and then is allowed to cool in a specific way (slowly, if I recall correctly). This is repeated until the cam journals check out. Then the bottom is surfaced, if needed.
I wouldn’t bet on that, but it won’t hurt.[quote=“semaphore1999, post:77, topic:11506”]
If I find afterward that my valve contact the pistons, how would I adjust the clearance?
[/quote]
The short answer is: you don’t. There are longer answers, but usually they start at “get new heads” and move along a dollar continuum to “custom machine work”.
But you’ve already figure some of this out:
Yep. Properly timed, the valves are not attempting to be open while the piston is in their space.
True, but it’s VERY unlikely on a street engine IF it’s properly timed. So: make sure it’s properly timed, first and foremost.
Secondly:
That should do it.
Remove the least amount of material possible.
And again, make sure your camshaft journals are aligned first.
TL;DNR:
1: Make sure your cam journals are aligned; if not, get a (competent)(with aluminum cylinder heads) machine shop to help
2: resurface if necessary, and the “pseudo holes” is DEFINITELY the limit. Hopefully you won’t need to go nearly so far, but don’t be afraid to get 'em clean.
3: keep the timing dead-on, and be careful verifying it
Please keep up the posting!
