17k on rebuilt motor and turbo, just did a compression check on my RX7, and the 1st rotor is no good (1 Apexi seal is gone), the second rotor is still good, can I just replace the first rotor or does the whole engine need to be rebuilt?

 

Since your in there you might as well do the complete rebuild, but yes from what I can tell you can replace just the one rotor if no other damage was done to the engine by the apexseal.

 

DON"T GO HALF WAY!! It will cost you dearly($$$) in the long run.( If it even starts again.. The reason I say this is because once you unload,or loosen the main block bolts that hold the entire engine together. You have "unsealed the entire engine. The gasket/o-ring contact surfaces have been altered and most likely will not seal properly again.) I also don't know of any engine kits for a 1 rotor rebuild. I guess buying individual parts would be one way,,, but it's not worth it. Unfortunately we( rotary owners) Must bend over and take it with a smile!!! Price of paradise i guess!!!1 Aloha, Dave

 

What would you suggest?

 

why pull all that and not do it right?

going cheap gets you broken **** later.

j

 

Mazda should reinvent the rotary engine so that apex seals can just be changed like spark plugs.

 

or how bout a 30min engine change service... oil change is 15min, motor change is 30.
(mechanic says) *ok your new engine is ready to go... see you next month...

 

Awha ha ha, hay what am I laghing at mines got a poped apex too...

 

You guys are nuts, there is nothing half *** about it if you do it right. Your motor won't leak if you unbolt it as long as you are careful enough to not pull the housings apart while changing out the front or rear seals. It's been done many time with zero problems. Only think you'll need to be careful with is the oil pan and sealing it back up.

 

The problem with o-rings is that they take a "set" as they get old. If the engine had new o-rings recently, you can probably do the 1/2 job ok. If the o-rings are old, they will have almost no elasticity, and you are asking for trouble if you don't replace them all.

 

Is it pretty hard taken the engine apart? how long would it take? Where are the apex seals located in the rotor?

 

Um, at the apex's

 

I wouldn't do it if you aren't somewhat mechanically inclined.



ps. I don't mean that in a bad way.

I've blown my motor up and had it running the next so yes it can be done quickly.

 

Just buy a rebuilt motor and install it. Don't do it half way other wise you will find yourself doing it twice.

 

dont mean to use your thread, but why isnt anyone surprised that the engine when in only 17k, is that normal on rebuilds?

 

A friend of mine did this a year or two ago and the motor is running fine. He's done numerous track events with it too.

Liavb21, if the car is not tuned properly, or something is malfunctioning you can blow a motor the very first time you get on it.

 

I'm thinking of trying the half *** job as well. I found out the rotarys don't take 28psi boost spikes to well. lost an apex seal on the rear rotor. 100psi on front rotor with 9,000miles of beating

So if no damage was done and I don't mess up putting it back togther it is possible??? what about straping the remaning housings together to keep the tension so the o-rings keep seated?

Man, I blew it two nights ago and am already having withdraws from not being able to drive. I need to put this motor back together cheap.

Where are some good places to buy the seals and stuff????

damn this was an old thread.sorry

 

I would try and just replace the bad rotor. If it works great! if not let us know so I dont make same mistake. Also what was your compression on the front rotor? The mazda dealership said i need new engine cause my rear rotor compression was 5.3, 5.7, and 7.1. They said i had bad apex seal.

 

Nobody works with partial rebuilds, for a very good reason. It will save very little time / labor and risk major problems.

If you want to get it fixed quick and cheap, consider a reputable budget rebuild shop like rotaryresurrection. Otherwise, get it rebuilt completely or put in a reman. Half-assing this job will get you in a worse position not very far down the road.

Dave

 

the poster doesn't know where the apex seal is on a rotor...obviously he doesnt really know much about rotary engines or how they work...so if it blew at 17,000 miles i can only assume that he overboosted.....WHEN THE FRONT ROTOR BLOWS ITS NORMALLY FROM OVER BOOSTING...well anyways good luck with the rebuild and dont do it half asse'd!

peace

 

no offense, but I don't even see the reasoning for you asking this. Its like breaking something and supergluing it so it works again, not smart and has a very low chance of actually working. seems ignorant to do what you are asking! get it rebuild, the whole thing!! quit boosting so hard! simple as that.

 

anyone else tried to do it or are you guys just speculating.

the problem is I just don't have $2300 for another reman cause I put this one in the car 8 months ago. If the seal was expled with out damageing anything and if I can keep the other housings sealed together with clamps or somthing, can you pull the rear housing, fix and reseal the rear housing.

 

Taking an engine 1/2 apart has got to be one of the dumbest ideas ever posted. When an engine pops you have no idea what other damage may have occurred.

Park the car, save your money and do the job correctly.

 

If you're in a rush to get the car back on the road then this "halfass" method works fine. Done it many times.

Too much mis-information on this forum.

 

You say the engine has 9k on it right? The undamaged housing and rotor will be just fine. Separating the engine is completely fine if all the internal seals are put back in there respective places. I don't know were all the paranoia is coming from? An engine with blown coolant seals can be opened and put back together with new coolant seals and re-used side, apex, and corner seals and run just fine. Don't get things mixed up. Completely take the engine apart clean it and replace whats needed. If parts are well within spec, there is no need to be unneccessarily replacing **** especially if the engine only had 9k when it blew.