Finally tore into my 1987 TII block.

Mileage is unknown. Engine apparently ran but smoked a lot.

Goals are to re-use as much as possible, street port it myself, and then 300-400whp on a budget!

This is my first rotary rebuild, so I thought I'd post up and see what you guys thought.

First thing I saw when tearing it open was a broken side seal...I suppose that could cause a bit of smoking.



Gave everything a quick once over and looked it over. I'm going to spec it out later. (need to find a dial indicator)

Front Iron - Pass



Front Stationary Gear - Pass


Front Rotor - UNSURE







Front Housing - UNSURE

 

Intermediate Iron - Pass




Rear Housing - Pass




Rear Rotor - Pass

 

Rear Iron - Pass (I think!) (This is where the broken seal was)




Eccentric Shaft - Pass






Oilpan - FAIL (giant dent)





So, let me know what else I should check...

 

I should also mention that the oil pump, rotor bearings, and needle bearings all passed. There was some minor scoring in the oil pump, but nothing I could really catch a finger on.

 

In my opinion the needle bearings should be replaced anyway. They are very cheap for not having to take your motor out again.

BTW, you should inspect everything again after a really good cleaning.

 

front rotor dont look so good. the front housing also does not look very good

 

the bearing in the front stat gear should be replaced

 

Looks like all the bearings should be replaced to me. How many miles were on this motor and was it the original?

 

i will replace all the main bearings,specs out all the grooves in the rotors and make sure that they are good,front rotor looks good for a budget i need a car to drive build but if you are shooting for 400hp try to get another one,i always replace the oil pump if i feel scoring on any on the pieces(good old oil pumps are cheap)and the rear housing has some moderate wear on it but it should yield around 90s after break in.

 

I don't know how many miles were on the motor. I bet it's original, still had 3 piece apex seals and no gasket maker holding it together. I really don't think the bearings look that bad, but now I'm not so sure.




graaarrrggghhh, this is going to get even more expensive than I thought. Did I mention I spent all my money on a haltech? lol.

 

If you cheap out now, you'll pay more later, you can bet on it. Not to mention time is money, do you have the time to rebuild it again? Bearings (needle, rotor, stat gear) aren't THAT expensive, I'd change them and have some peace of mind. And you should really give the rotors a solid OCD cleaning to be able to really see if they can be re-used.

 

The front housing is a fail.

All the bearings look ok to me(from what I can see). The outer coating on them is very thin. I'd bet that they will still spec fine.

 

I'll spec out the bearings and replace the housing. The rotor looks good other than that one spot, so I'm still not sure. Any more opinions on that rotor?



I know what you're talking about on the not cheaping out on important parts spiele...that's why I spent all that money on fuel management...you get what you pay for....

and at the same time, that's why I'm pissed at having to purchase these parts. By no stretch of the imagination should 12 flimsy little pieces of metal cost 108 ******* DOLLARS! (Side seals). You look at a $900 rebuild kit, and what did your 900 dollars just buy you? A few scraps of wire, some rubber seals, and a bearing or two...I think the problem with internal engine parts is that everything is priced about 10x what normal retail should be because nobody makes them

 

If the only thing that is wrong with that rotor is the mark on the face it is 100% useable.

Lightly sand the rough edges down and you're good to go.

 

is that a chip? if so is a def fail. that place is a weak point for the engines.

 

^ looks like a chip but if you are on a budget you could get away with building it back up with some epoxy.

 

There seems to be a pretty substantial crack on the Leading plug hole of the rear rotor housing.
Its hard to tell how big it is from the photo, but that's something that should be checked out.

Also, make sure to check over ALL of the coolant seal passages very closely.
Ive had bad luck reusing irons that I wasnt 100% confident in.
Rebuilding a motor because of a coolant seal is a real bummer.

 

Cracks in the spark plugs area is really really really bad according to Mazdatrix I think. They say any crack makes a junk housing.

 

Thanks, guys! This is the kinda stuff I was hoping for help on!

I think both of the areas in question will be okay, other than everything else we've found wrong.

The iron is just missing the gasket there.



And the housing...it's not a crack, it's a "flaw"...or a "scratch"....it's shallow and doesn't continue past the first bit you see.


But I think I'm going to replace that housing anyways because of the chunk missing above it.



What kind of chemical do you suggest to give this an "OCD cleaning"? Simple green automotive? I don't have access to a parts washer

 

Yup. you caught it too. I wouldn't use that iron unless that seems to be a flaw in the photo.

Gasket remover.

I'm concerned about the front rotor but you can't really tell until it's a bit cleaner.

The front iron has already been discussed. Where it's circled in red should be inspected thoroughly. The pic that you posted above is not of the same area.

The front housing is a fail, the rear is marginal at best.

So, you're looking for a rotor and two housings and a front iron. I would start looking for an N/A part out. Most of them have great condition housings. At least the ones that I have seen even after 19x,000 miles looked better than turbo motors with less than 1/2 that. That could potentially give you your two housings and two matched rotors. Then all you would need is the front iron.

Let me put it this way, I pulled out my S4 N/A motor and coated the internals as best I could with some oil. I put it in the basement near the furnace and every so often I'll go down there and pour a little more oil in and rotate the motor a few times just for when I pop a motor, I have the rotors and housings ready. That motor came out of the car with 233,xxx on the clock

 

Funny you should mention that, I've got an 86 N/A engine sitting in the garage...compression was 100/95 when I pulled it.

 

Uhm, unless I'm missing something, the two pictures you quoted are of the exact same area. There's no chip in that iron, so I reckon I'll use the TII irons with the N/A housings and rotors I have out back, yes?

 

Sounds like your housing/rotor issue is solved. Just swap the exhaust sleeves before you port the housings and you're ready to rock and or roll.

I'm not sure what's going on with the pic's unless you pulled out some gasket material after the first round of pics were taken. In the first pic, where a member circled in red, it really looks like there is a chip in the coolant passage. I would pay incredible close attention to that area as it is a known weak spot for seal failures. Check out pics # 4 & 5
http://www.mazdatrix.com/faq/sidehsgs.htm

 

If you want, I've got a S5 oilpan and S4 NA rotor housing I can hook you up with.

 

s4/s5 oilpans interchange? I was going to see if you had an oilpan.