GeneralDisorder

They are the same basic design, but there were changes to the block and head castings to accomidate larger coolant flow, and to incorporate the coolant by-pass that used to bolt on beneath the manifold on the EA71 block. The head studs do not line up from one to the other. EA81 heads necesarily have larger valves, but the intake and exhaust ports are about the same. The stock fuel and ignition systems are about the same - the electronic distributor from the EA81 will bolt up to the EA71 without modification. But the manifold for the EA81 is longer and actually matches the EA82. Making SPFI possible on the EA81, and not on the EA71. Also the transmission bell-housing changed such that the EA81 will not bolt to the older EA71 transmission. The starter was moved from the top 1200 posistion over to about the 1330/1400 position. GD

No, and the Sub4 heads are for the EA81. They will not fit the EA71. There were no performance variations of the EA71 - not in the US market anyway. And EA81 heads will not fit - besides that they are not dual port anyway. GD

Take a reading with a mechanical guage. Maybe you just don't have much pressure. Personally, for the cost of the sending units you can install a mechanical guage and be done with it. That's my preference. GD

I used 5 watt 33 Ohm ceramic flame-proof resistors. Seems to have worked fine for me. The package of two was a whopping 89 cents. GD

40 Ohms is too high. Needs to be about 33. GD

Even my local dealer (that stocks both parts) gave me that one at first - new guy behind the counter. When I made it clear that I needed the cam tower oil PASSAGE o-ring they figured it out. Yes, you *can* use a normal non-reinforced o-ring. Prior to like 87 that's what they had from the factory. It just doesn't last the proper 200,000 that it should. Should be no trouble for at least the next 50,000 though. Just match up what you pull out to a new high-temp o-ring. Dealer is wrong about it being "obsolete". They are still in the system. And yes - thepartsbin.com is the same OEM part as the dealer. Whatever you do, you MUST replace that o-ring. The old one will be unusable. The one they gave you.... yeah I don't personally ever replace those really. But that's because I don't generally take the front cam seal off unless I'm replacing it/them. GD

This has been covered - you bought a TURBO. Takes your lumps like a man. GD

The fact your coolant is pressurized the next day is enough to indicate a failure. One of the passages adjacent to the cylinder is leaking. Cylinder compression is entering the cooling system. I've seen it several times, and two of the ones I replaced I could actually see the failure and the damage it caused to the head surface. With the mileage your engine has, it's almost a guarantee. Water pump failure was the last straw for my 86 with 228,000 on it. New HG's was all I needed as I didn't drive it enough with the failure to cause the head surface to be badly pitted. But I did actually SEE the failure in the gasket when I removed it. It was small (1/8" wide), but it was there. ASE certification is good general education, but doesn't trump first hand experience with specific models, which is what this board represents. I have "military training" as a mechanic if you like - doesn't mean I know what's wrong with your mazda..... good example for you: Freind's wife has a 2000 Jaguar with a V8. One day it doesn't start. I figured electrical or electronic. Turns out that short drives on this model will wash the oil off the cylinders and the engine's compression drops so low it won't start. Solution was to squirt a fluid ounce into each cylinder. It cranked up after about 5 minutes, and blew a huge oil cloud for 20 minutes. Silly? Yes, but ASE doesn't prepare you for crap like that, or other model specific anomolous behavior. No amount of education does really. Rick

That stop leak stuff doesn't work on flat-4's due to not being able to effectively drain out the coolant from the heads. Plus there's no way it's going to fix the exhaust port crack if that's your problem. Just sell it as-is so at least someone has a chance of not causing more problems by thinking there's nothing wrong with it. Trying to patch it with that crap is underhanded and dishonest. Besides that it won't work - not even for long enough to sell it. It just won't work at all. I tried it for the hell of it on my sedan - I was rewarded with no heat, a mess in my driveway, a head gasket job the next weekend, and a VERY cold heater core replacement job the following month ...... hey - I like to do some "mythbusting" once in a while ya know? I pretty much knew it wouldn't work but I figured (wrongly) that it couldn't hurt. Well it can, and will, make a holy mess and it does seal things up but good - just not the right things. After I replaced the HG's like I should have done in the first place it's 100% again. I've put 6,000 on it since, and haven't added a drop of coolant. "Takes your lumps" like everyone else who is unwilling/unable to fix things properly. Don't crap in someone else's cherios. GD

On the other hand, my 86's AC system got a bit low and no longer cooled. I replaced all the o-rings at each fitting with new AC rated stuff, and charged it with some old R-12 I had around. Didn't replace anything, and didn't pull any vacuum on it, and it's working fine. If I have to charge it up again with R-134 in a year or a few years so be it - the stuff is cheap. These old AC systems are simple, and frankly the whole receiver/drier setup isn't that big of a deal. Older refrigeration and home AC systems don't even have them. Make sure you have it setup properly to come on with the defrost, and that the idle up solenoid works - this circulates the oil in the system durring the cold season, and prevents hoses, rings and seals from drying out, and the pump from eating itself. It also dries the air for better defrost action. GD

I got a 36"... or maybe it was a 48" from summit racing for like $35. Came with the fittings, and it's specifically for oil, and other pressurized applications. I used a metric to NTP adaptor, and a right angle fitting to attach it to the pump housing. Mine runs to an Autometer sender that I bracketed to the drivers side fender wall behind the battery, but you could use any brand of sender. I did this to avoid the 3" long sender sticking down in front, and I used SS line to avoid any potential problems from snaging the line on a small branch or something that might get behind my skid plate (which is large and formidable). The silly plastic tubing they sell for mechanical guages is fine for street vehicles, but the cheap thin stuff they give you with the $7 walmart guage is both too weak (kinks easy, and the cheap fittings leak, and easily cut the tubing), and too short to be of use. I ended up buying a VDO 12 foot length of tubing for my wally guage in my sedan. You need about 7 to 8 feet of tubing depending on where you locate the guage, and the cheap package comes with like 5 feet. Basically because of the subaru layout, and because of the metric to NTP adaptor needed to convert the sender threads, you are looking at around $35 - $40 minimum to install *any* guage. If you buy a cheap guage, invariably you will require better/longer tubing and fittings to make it work, so you might as well invest in a decent Autometer setup. I have a Volts/Temp/Oil 2.25" cluster in my wagon that was about $65. Then the SS line and adaptors was about another $45.... so $110, but I also got *reliable* temp and voltage - which was very important for my application. Also - unless you stick with a brand name guage, or purely mechanical guages, replacement sending units may be difficult to find or expensive to purchase seperately. For this reason I choose to only buy quality brand name electric guages like Autometer or VDO. GD

Take the whole assembly to a smith. You have to drill a hole in the side somewhere to gain access to the barrel. I've seen some that have been re-keyed with new barrels and such. GD

Go take a look at a feeler guage and then visualize taking that thickness out. For reference, even .030" is less than a spark plug gap. So no, it doesn't matter. .020" is *technically* the max if you go by the FSM. But many have done .025, and .030 with just a slight oversize of the manifold bolts. GD

.020" for the manifold to still fit stock. .025" or even .030" if you drill out the manifold bolt holes a size over (no big deal). GD

Read that statement a few times to yourself. It's contradictory. It cannot both indicate what's going on, and have no relavance. It makes no difference because pressure is the only reading we have to go off of. Personally if I don't see a reading above 15, I want to know WHY. Just like if I see a temp above half - I want to know WHY. GD

81 has the pump in the engine bay. Pretty sure it only has one filter. GD

Once you've had a rod go through the block you'll be a lot more careful like I am. Blind ignorance of the true oil pressure might be alright in some cases, but it will eventually catch up with you - maybe not on your current engine, but eventually. "A man that doesn't read great books is no better than a man that can't" -- Mark Twain. Not knowing your real oil pressure is as bad as not knowing what oil pressure is. Both scenarios end the same way. GD

The pressure switch screws into a different port than the guage sender. The idiot switch is on passenger side of the pump, and the guage sender screws into the bottom. This is the proper way to do it on an off road rig - SS braided line to a remote sender: GD

Actually it's not. But this has all been discussed before. A simple search will yeild all the info you could want on oil pressure. I'll just finish by stating that anything below 15psi hot idle is SCREAMING for a diagnostic. And personally I don't like anything below 20. GD

It doesn't actually matter - the core is symetrical with respect to flow. Hook it up however the hoses fit best for you. So you could reverse the lines after you flush it just to help it out. *note* - this is NOT the case for EA81's. Only EA82's. GD

The original poster has been asking about a "lifted" rig as a daily driver in other threads. This thread is just an extension of sorts I think. He didn't mention it, but I'm pretty sure that was the intention..... for the record though I wouldn't run welded with regular tires either, but it may be alright for some. GD

86 EA82, 231,000 miles. Aftermarket mechanical guage, resealed oil pump, new cam case seals. Cold idle: 90+ Hot idle: 25 Cruise: 60-80 GD

Or crack an axle cup. I've blown 2 on pavement with 28's. And it takes all of 5 to 10 minutes to install or remove an axle. The LSD's don't work well with large tires. The friction plates in them weren't designed for large tires. If all you are doing is snow and occasional "off-road" then you don't need anything. Open diffs will work fine if you know how to drive. GD

Pull axle. LSD's aren't that great for real off-road. Better than nothing, but they are the lazy, expensive, less-effective solution. Welding is better on all accounts. GD

Sometimes getting under the hood and in the process of smacking the starter you move the cable a bit, etc. It happened to me anyway. Just one of those things. GD