Can u rebuild a engine with scraped housing. Like after u have blown up your engine due to a apex seal (s) breaking.
Is it ok to sand down the housing to get rid of any marks the seals have made.
Will this work and if would the compression be good?

thanks

 

The answer to your question is pretty simple. Yes, you can make a rotary engine out of junk parts. It will be a junk engine and probably last 2-3 hours at best.
You can't sand down the rotor housings. They are coated with a thin layer of chromium. A rotor housing with minimal chrome flaking can be reused, but one that has experienced heavy damag from a thrown seal or warped from overheating must be discarded.

 

BULL! it will last more than 2-3 hours.....where did you get that idea?
you are right about not being able to sand them down....but a used housing that was not the "problem" side of the motor can be used w/ no problem. then again it all has to do w/ the wear on the housing. even a housing w/ a lot of the usual visiable wear around the edges can be used for a good 15k miles. dont want to start an argument, bu tit WILL last for more than 3 hours at best! for every 2 motors you blow, you have 1 good one sitting there.

 

Make sure you inspect the damages. Check www.Mazdatrix.com They have pictures of good to bad useless rotor housings. Also measuring parts into spec is the best way to tell is the parts are worth using for another rebuild. Side housings also needs to be lapped or resurfaced especially if the cause of the motor failure was OVERHEATING. Most likely that the side housings are warped and need to be flattened again. If you want i just took apart a 87TII motor and found some scratches. I will take it to my friend's shop (rotary shop) and have him take a look at the housings and see if they can still be used. They are also ported!!!..also i have side housings (ported) that came from the same motor. If you want to make a deal with those parts let me know!..email me at FCTURBO2@hotmail.com

 

They don't NEED to be lapped. Yeah it's a good idea, but if the wear is minimal then screw it.

I have a set of overheated housings. They're blued, and blued housings are scrap, as they're probably warped and definitely can't be lapped, as the blue parts are hardened.

I remember a website where a guy on a low budget rebuilt his TII's engine with new seals and replaced his junk rotor and housing with good parts from a second, donated blown TII engine.

Here it is: http://rx7.freeservers.com/rebuild.html

 

The amount of BAD ADVICE given on this forum is unbelievable.
go ahead and flame me. I'm just saying junk parts = junk motors. Do what you want.

 

This is one of the funniest respond i've ever seen. If you are being a cheapskate go ahead and use scrap housings!..Mazda dont recommend using warped housings unless you get them lapped. Its only 50 bucks a face from MAZDATRIX. This guys spent years of experiments on this unique motors. If you are going to use a used side housings for god sake measure it and make sure its worth using for another rebuild.

 

I agree with you on that one!..its why im using brand new housings on my next rebuild.

 

I have to agree with the smart post made here. Junk Parts = Junk Motor.

If you can't do a proper rebuild ( and I'm not saying ALL NEW parts ), then why bother at all?

This is not a blender that you're fixing. It is a motor where very tight tolerances are needed. You could rebuild it and it will run, but it will be low on power, life and will use more fuel as a result of its compression leak, which is what you get when using parts that are out of tolerance.

The tolerance issue is so critical that on side irons, if you can feel the step made by side seals and/or corner seals with your fingernail, the part is out of spec and most likely useless since lapping of irons on rotaries made after '86 is limited to only a few thousands of an inch, since the grooves for the water seals are here and limit the amount of material to be removed.

I have rebuilt several wankels, mine and not, and always try to use as many new parts as possible. The two guys who I rebuilt crappy engines for came back in less than a year/8000 miles.

This is a case where the product is the sum of its parts.

Kenneth

 

Holy. Sh*t.

This might be a record.

 

You're right.

It is a pretty old post, but people might still find in it, an answer to their question. I just go reading posts and comment on those that I have hands on experience.

I say this because some people here, give an answer based on their ramblings and not as a result of experience.

It might be a record though!!!

 

well at least everybody agrees that you WILL blow up motors,at sometime.

we sure are a strange bunch!