@wanderson
Blue shop paper towels are usually good for most solvent work. Let them dry out before you put them in an enclosed trash container.
Even once you get it solvent clean, a light mechanical clean is probably a good idea. Even a household scotchbrite and elbow grease will take a tiny fraction of a thousandth and bring up a shine, proving the tiny film of residue left by the failed gasket dissolved in solvent has been removed.
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OK gentlemen, thank you all for invaluable feedback. I will now set out on my early AM scavenger hunt to find the various implements of which we spake. Iāll report back with developments.
Hopefully soon I will report back with Mazda in Zoom Zoom modeā¦
I will be sure to let the traffic cops and their monthly quotas knowā¦
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ā¦and deploy the cloaking deviceā¦
Here is an additional concern I am having:
In reading the mazda service manual, it has become apparent to me that not all hoses are hooked up properly. There are numerous vacuum and coolant hoses along with a myriad of vacuum switches, actuator, solenoids and what not. Now the manual is good for stepping through them, one by one, and how to use OBDII to stimulate them and also how to verify that they are doing what they should.
What the service manual does not describe well is how they should be connected. In other words, I do not see diagrams showing the proper connections for the purge solenoid. I also do not have a diagram showing where the EGR boost sensor attaches its vacuum line. My EGR boost sensor is connected to a vacuum switch, which makes no sense. Why would you ever switch off the ability to switch whether or not the sensor could detect the pressure level that indicates to ECU whether boost is properly engaged? Clearly I have a problem here. Things are not properly connected, and I bet this may very well have to do with why I experience an āidle huntā situation once engine is warmed up.
I think that a vacuum hose review is in order for this 2001 Mazda Millenia 2.5 L V6, along with checks to ensure proper operation and vacuum levels. Now I already have a map for VRIS vacuum lines. Does anyone know where I can find vacuum line map for EGR, purge, and anything else using vacuum lines? Also coolant line map would be helpful.
You should use as many washers as the manufacturer recommends. Usually this is one per bolt, especially on aluminum cylinder heads.
Hmmā¦ 2mm~=.07874 inchesā¦
That seems too big, to me, but perhaps Iām misunderstanding. (if you actually mean āmilsā, thatās weird terminology in this application, but that would be .002 inches, if I understand what āmilā is correctly, and thatās just fine)
Yep. Usually the phrase is ālint free clothā, but we all know thereās no such thing. Walterās suggestion of cheese cloth is likely good, but Kevinās suggestion of blue āshop ragsā (HD paper towels) is more āreal worldā. Either should be fine. Just keep the debris to a minimum, and out of the cylinders, specifically.
As for solvent: use whatever you have lying around. Gasoline works great, but is highly risky. Diesel works very well, but likely you donāt have any. If youāre going to go buy something, carb cleaner. Keep it off anything rubber.
As for vacuum diagrams and/or coolant system diagrams. Vacuum diagrams can be had online. Nothing of quality, Iām afraid, and nothing I care to quote here. There MAY be diagrams under your hood, too. This was something manufacturers once did, usually with a sticker. Often it disintegrates and/or gets lost otherwise, but maybe.
Cooling system diagramsā¦ never seen oneā¦
Good luck!
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I recant any concern about head bolt length. Max allowable is 5.217 inches, and each one measures less than 5.25 inches, by how much I am unsure. Best I have around is ruler, but from what I can tell by threading the bolts deep into the short block, I have plenty of room to spare. I donāt need any washers.
As for the flatness of the heads:
1 mil = .001 inches
So from my measurements, any deviation from perfectly flat on the bottom of the heads was less than .005 inches. I would say the deviation was probably .003 inches, and was very location generalized, meaning whole sections of the head would allow the .002 inch feeler beneath, others portions would not.
Here is what I plan to use to remove previous head gasket gunk from Mazda short block. See pictures.
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I remember you saying you took lots of pictures during the teardown. Was that just the engine disassembly itself or do you also have shots of the wiring and hoses before you dismantled anything?
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I have a lot of footage. Video footage. So much, in fact, I just moved a whole bunch of video footage off android devices onto a more permanent storage. I moved ~10 Gig or so.
Problem is, I think I reconstructed things as they were when I got the car. That is not to say the stuff is hooked up properly now or when I got it. I suppose I could have erred. But I donāt think its outside the scope of possibility that I got the car all goofed up, and it is still goofed up. So Iām not sure that seeing how things were hooked up answers the question about how things should be hooked up properly.
And this is interesting about the head gasket I installed previously. It is in no way a dual steel head gasket. Instead, it has a perforated inner metal sheet, with what may be graphite on either side. There are piston rings of what may be steel intended to seal the cylinders. I had to do some considerable sanding on the heads to smooth out the indentations where steel had pressed into the heads (probably from old gasket). The point of interest here is that I believe that the material on the short block is graphite or graphite composite of some sort. This explains why I said it was malleable. So what in the world removes graphite? And I did a bit of this with plastic and my fingernail, both of which removed it pretty well. It seemed to get everywhere, however. What are the impacts of getting this stuff inside the engine?
update on Permatex Gasket Remover. There was once an old product that was pretty good. It is discontinued. The sutff i have is utterly useless according to the vast majority of Amazon reviews I read. That stuff will go back to Oreillys unopened.
Word is I should scrape off the graphite with plastic, then polish with cloth and brake cleaner. Sounds like great fun.
Those are steel fire rings around the cylinders. Even shitty gaskets require this these days, to survive at all. The pitting you had to sand out of the head is fairly normal in an engine this age (based on description).
It probably IS graphite matrix of some sort. The affects of graphite in the engine are largely negligible, but who knows what all else is in the matrix. I wouldnāt worry too much about it, but changing the oil and filter, and maybe coolant, would be advisable (and would be, frankly, regardless of the material). To be perfectly honest, most folks would ignore that advise and likely be fine, butā¦
Myself, being a cheap cheap cheap explative, would filter the existing coolant and put it back in. I WOULD use new oil & filter, though.
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Iāve wrestled with it all day, got most of it off. still wrestling with it thoā¦ Plastic ice scraper, followed by papertowel/wd40. Iāll send pics when I am done.
Also, I elected to shell out for felpro gaskets. Iām redoing this because of eBay head gasket, bottom line. Not gonna do that one twice.
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I found some great reading material about regasketizing headwardly Mazda the.
One of the most powerful points that resonated betwixt both of my brain cells was this: repairing a head gasket is more involved than the task of tearing things down, removing, cleaning and properly installing new gasket. The most important aspect of the job is identifying the mode of failure that cost the owner one reistallation. Of course, knowing why failure occurred is not enough. To repair the head gasket, the prudent repairman must remedy the undelying mode of failure, else (s)he will be caught in 10 repair gasket; 20 goto 10. I just spent countless hours in that loop, and so recently one of my neurons said, āhey, other neuron! I have an idea that could allow us to work on something thatās not mazda!ā
Snice Iāve thrown out a Lotta maybe it was this theories, I want to nail down my root cause, with the option open for feedback from those > 2 brain cells who may have ideas my 2 may have missed, and could return the electronics enthusiast to something heās not awful at.
I believe that whether the rod was bent before or after I took possession of the beast, the root cause was overheating. I had noticed excessive heat from engine, nestled in a myriad of other problems so it took a number. I have straightened out 95% of the troubles now, so individual concerns can be isolated symptomatically. But prior to that, the head gasket was getting worse with each engine heating due mostly to clogged/slow flowing radiator. The temp guage stays low, since it is where coolant enters the engine, but since not enough flow, engine potions in subsequent coolant flow get progressively hotter. During first couple of weeks with new head gasket, I must have overheated car minimum 10 times, cringing each time as I realized what I had just replaced did not fix overheating concern. Finally, now that new thermostat, upper and lower hoses, temp sensor, fan relay, and other adjutments I prolly forgot, I went all radiator up on that. Alas, cooling problem solved (after coolant leak, then transmission fluid leak were both solved)! I saw no further indication of overheating, so I drove around a bit. Sadly, during this first drive, I noticed a bit of white smoke shoot out the tailpipes at the end, and enjoyed the aroma of coolant to top it off. I hoped it would be that the gasket was just seating itself properly, because the engine ran like a brand new mazda. But, that hope died as I continued to drive it, noticing it got worse with each successive drive. I parked the mazdabeast, and deliberated for weeks before facing the reality that I must eat crow in the form of replacing head gasket once again.
The silver lining in all of this is that upon this installation, the radiator is new, so as long as I get air bubbles out of coolant when I fill, I think I may get to break gasket in normally, without overheating. This fact, coincident with clean, flat surfaces, and the felpro advertised MLS adjustments to gasket design to be more forgiving to surface imperfections, sets me up for a possible fix for Mazda Unfixable.
Appropriately linear, or optimistically short sighted? What am I overlooking that I should not?
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Oh, and I think I know how the composite failed!
Check it out. The reason industry has gone with multilayer steel (felpro has 3 layers) is that the layers allow the heads to shift relative to the block, as thermal expansion dictates. The eBay composite (seller refused to identify manufacturer, told me to ask mazda what was in material. I was asking so I could figure how to remove, but they went all jerkwardly unpromptedā¦mark of the guilty) is one piece. IT has single metal mesh with graphite on each side. Shift required= squirts of coolant into cylinders and vice versa. No wonder seller running for cover!
Worder to those wiser than 2 brain cellsā¦given time and expense involved in head gasket replacement, the cost of quality gasket is very secondary.
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It largely seems like youāve got it licked, from your description, with the radiator. I find it peculiar that your temp gauge is not showing properly. They are usually located on or near a cylinder head, so the temp it shows SHOULD be what the head is at. Of course, there may be any number of other factors.
If you have a non-contact thermometer, this might help you on your first test drive, to be sure itās all OK. Point it at the hoses, when itās at temp, and they should all be about the same temp (likely in the 190-220 Farenheit range).
If I may ask, how did you deal with the overheating events you think occurred? Obviously, we hope it doesnāt do that at all this time, but maybe a plan for what to do with it if it does can help. My best advise on this is: donāt be in a hurry, or far from home. The smartest thing you can do if you see it overheating is shut it down and let it cool off. Try to fix whatever the cause is, and try it again. Maybe retorque the heads, if you really think it got hot. Trying to ānurse it homeā is bad news. And contrary to television, the right thing to do with an overheated radiator is NOT to pull the cap. Thatāll get you scalded AND makes it harder to cool down.
Still, from your description, it sounds like you may actually have the beast tamed. (apparently we need a ācross fingersā emojiā¦)
The graphite gasket makers swear the graphite does the same thing that FelPro claims the MLS does, and thatās why you should use graphite gaskets. I have used them, and they work OK (seen others put 100,000ās of thousands of miles on them; Iāve only ever gone 10ās). But yeah, the MLS seems to be better, in my opinion.I might just be giving in to the marketing, though.
Truer words have not been spoken. And itās not just head gaskets, either.
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Let me eat some words. Apologies, but a lot transpired, and I may have communicated an old working theory, subsequently replaced by reality when I discovered that the guage did in fact register overheating once new sensor installed.
And it seems I remember something about upper radiator hose sourcing coolant to radiator so temp guage at end of engine. AND then there are air bubbles that work themselves out, but only after thermostat opens. AND donāt forget to crank the heater initially for some reason, maybe get those bubbles tooā¦
Regardless, issue is same: overheating concern leads to extreme cylinder pressure, leads to head gasket failure, leads to me wasting incredible amounts of time and energyā¦
FIX us the same too: apply reasonable diligence, listen to field experts, more haste=less speed, e=mc^2, Never Eat Shredded Wheat. Boom, just like thatā¦
Thx. for assistance, gents. One day soon I might arrive in Mazda as opposed to pushing Mazdaā¦
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Shouldnāt need to do that on modern systems. This is a hanger-on from the days when heater cores were valved. Nowadays, the coolant runs through the core all the time, and whether it touches the air is controlled by an air flap.
But it aināt gonna hurt to make sureā¦
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Also remember that the heater core is a mini-radiator. Crank it to heat, full-blast fan and roll down the windows. Sometimes thatās just enough cooling to keep it under control and get it back to the garage.
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ā¦almost as if there was heat exchanger in that Hester coreā¦
Iām still trying to decide if 2001 is considered modern or not. Seems I remember breaking down and purchasing my first cell phone around that era. Motorola flip phone via att that took up to four button presses to generate a single text character, and puchased at the dedicated att store located gasp in corporate office builung on company campus. Little did Michael know that little store was a beacon illuminating what would soon decimate his empireā¦
So Iām still at a loss as to whether or not flipping the heat switch is technically requiredā¦lol.