MX-3.com

Hey all, i dont actually own an mx3 first off, its my brothers car. But since im the mechanic, figure ill come here and ask the questions. car is a 92 i think, with that 90hp sohc 1.6L driven by a 5speed.
Anyway, the point of my being here: he bought the car for like $400... and on its maiden voyage home conked out. should have jsut junked it there, im sure.. but it was already registered. Anyway, i get to it and notice it has no coolant.. add some and check the plugs... the coolant is leaking right into cyl #1. fine, ok.. no biggie, so i wait till a good weather day to pull the head and find what i can only imagine as VERY BAD detonation damage.





That is what im looking at, the messed up one is cyl #1 and the other one is #3.

I WAS going to send it to a machine shop.. but i dont think they can save that.

So other then a "wtf caused this!?" does anyone know where i can get a head cheap? no power adders.. just direct swap info. I already have enough custon s--- going on with my turbo pulsar, i DONT need two custom projects.

i would just get a motor from a wrecker, quicker and cheaper. where are you located.

Well im located in Cape cod, Massachusetts.

I dont think a whole motor would be easier.. this was the easiest head i have ever pulled off.

I cant see how a head wouldnt be reletivly easy to come by. Its a tiny lil motor and shouldnt be that big of a deal. Also... the head weighs nothing compared to my dohc nissan.. its funny.

Shipping can be a little cost prohibitive. Ryan may have a head, PM him. As far as just changing a head, your a mechanic so you know a straight swap is probably fine but redoing a head then installing it ususally leads to a blown motor.

Its a 1.6L SOHC. 78x83.6 Any of these cars have a head that will directly bolt on:

92-93 1.6L MX-3...
85-94 Mazda 323/Protege with a 1.6L, 16v. Although, there's no reason the 8v won't work either.
87-89 Tracer

and a few more, but that range of 323 should be super easy to find.

If you want to do your bro a favor... just drop in the 1.8L BP... Tracer LTS, Protege LX, Escort GT.. its direct bolt in 40 hp...

Hey that helps a bunch ryan, ill call some bone yards tomarrow and ask around.

I dunno if he needs any more hp... he smashed up a 94 sentra, speeding down a backroad. He also has a lead foot on the highways, LOVES to do triple digits... ill be adding NO power to his ride anytime soon. Plus cost is a factor, hence the $400 price tag on the car to start with.

Normaly we would have just scrapped a car like that.. but he already got it registered and whatnot.. plus its really easy to work on so i have no problems fixin it.

Surprised no one has made any comments about the actual damage you can see...haha

lol f---in mazda junk!

Don't blame the Mazda for the dumbass who let it run out of coolant, and then failed to notice a destroyed headgasket. The B series engines are extraordinarily reliable with basic TLC.

I suppose overheating and detonation could have caused that but I'd guess that it just got really hot and cracked at the weakest point. Either way...it's broke.

Im not blaming mazda, the fact that it kept driving even with this much obvious damage stands as a testament to a well built car.

Had a machine shop looked at it just to confirm my fears. They voted for the death of a head and possibly the bottom end since how obvious the overheating damage is.

So now the question stands... do we throw a motor at it? can a sohc 16L be had for cheap? i mean i have a bunch of headgasket related parts for the car already, i could freshen up any boneyard motor easy.

Im gonna make some more calls tomarrow... feel free to chime in with cheap prices you've seen mx3 motors.. thanks all.

I wouldn't pay more than $300 for the motor: pulled, and delivered.

Since your going to pull the motor now anyway.. before you buy another engine.. why not take the engine out.. put it on a stand.. take off the oil pan and inspect the crank & rod bearings on that cylinder. If the bearing clearance is still good.. and the rings dont look trashed.. the bottom end could be fine. They really are pretty hardy little engines. If there is no obvious piston damage, then why not? At worst case you already have the engine out and are ready to put in a replacement. But might save some coin with 30 minutes of inspection.

I dunno for certain what caused that damage.. but when I look at the threads from both pics.. the threads in the broken hole look closer or like a finer thread to me than the other spark plug hole. So at a guess.. I think someone forced in a incorrect sparkplug or crossthreaded a sparkplug into that hole at one point in time. Just a guess but thats what pops to mind while looking at those pics.

The 8 valve 323 engine is supposed to have a bit more bottom end torque from what I have heard. And the engine is a bit more common to find in wreck yards too since more of them were produced in the late 80's compared to the 16v engine in the MX-3. Supposed to be identical bottom ends too.. but I havent seen both engines side by side to compare so this is a bit speculative unless someone else here wants to chime in with a bit more clarification.

Tunes67

Im in Springfield, MA and have a 215k mile B6 sitting in my driveway if you want it for free. Ran like a champ when I pulled it out for the BP swap. As you said, you have stuff for a refresh anyways. Didnt smoke or tic.

Well pox, all that costs is gas.. and a truck. haha, i think you sir jsut beat a junkyard price of $350!! lemme confer with the brother since its his money/car. but long as i can find a mode of transport i may be taking that from you

The B6 is the sohc 92-93 motor right? im not familiar with you guys and ur mazda motor codes yet.

I have the B6-DE. Which is the DOHC version. Its from my 94 RS.