I took apart an engine to rebuild it. and on my opinion everything is good inside but I'm a little doubtful about this housing. it has a very small scratch. so I'm asking the experts. should i use these housing or should i buy another one? this is for a S4 Turbo motor. I would also like your oppinion on the rotary aviation Super seals (black ones). should i buy them or not? My plans with this engine is to do a streetport and exahust port and about 10+ psi boost. thanks in advance.

 

Check the area near the trailing plughole carefully for a matching scratch. If there is none, then the housing would be fine. Take a flat razor blade and scrape it across that scratch, like you are trying to scrape off a sticker. If the blade catches, then the scratch needs to be ground down lightly to get rid of the high spot. Left alone, such a high spot would wear into the apex seal, and then when the seal came around to the other side, there would be blowby.

Once the high spot is gone (if any) then it will be fine. A little carbon will build up there until the surface levels off with the surrounding area, and the engine will run just the same.

 

Most of the time if its just before the exhaust port it is okay to use. I see yours is after. If its just a "scratch" then you shouldnt have a problem but if its deep than I would consider other housings.

 

no other scratches on the housing thats the only one thankfuly. should i just wear down the high spot with a dremmel or something or should i take it to a shop to get it done?

thanks in advance.

 

just use a stone bit on a dremel tool. Just barely touch it, and be careful when you do. Grind with less force that you would use when writing with a pencil. IF you are not used to handling such tools, it might be a good idea for you to outline the area with a couple layers of duct tape, kinda like what a surgeon might do when operating.

 

ok man will do. thanks a lot for your help. I will keep you posted

 

That is some HORRIBLE advice. That housing is fine, as other said so long as its minor and being after the exhaust port is OK. Being after the exhaust port is actually BETTER then being before it. BUT DO NOT USE A DREMEL TOOL ON IT!!!!! And absolutely not with a grinding stone. If there are any high spots (use a credit card or finger nail, not a freakin razor blade to find it) then rub the high spot out with some fine sand paper or emory cloth.

~Mike..............

 

Don't use scotchbrite either.

When I worked for a race team we would take a pill bottle or something like that and wrap a piece of newspaper around it to clean soft metal residue off the surface. I would imagine wrapping a piece of 2000 grit sand paper around a pill bottle and gently burnishing the scratch would work nicely.

 

Everybody has their own way, but don't scare the guy away by telling him (wrongly) that your way is the only way. We are not launching a space shuttle here.

Touching up the high spot lightly with a stone might not be the most precise way of doing it, but think about it...there is ALREADY a low spot there, the small area is already compromised, so it doesnt really matter how much you take off inside that area.

Also, creditcards and driver licenses can have rough cut edges that are not perfectly flat...straight razors are fine cut and perfectly flat, a good method to use to test the housing for flatness. We are not talking about carving your name into it with the sharp edge, we are talking about a 45* push across a surface as a flatness test. This will in no way harm the housing...in fact it is often necessary to use a blade to scrape off old carbon near the plugholes and exhaust port.

 

Some guys are simple engine ASSEMBLERS, while others are BUILDERS. I've seen time and time again work of "assemblers" and I usually end up fixing what they fucked up. These are the kind of guys that make huge ports and fill in the water jacket with JB WELD that they fumbled and accidently grinded into. These are the kind of guys that leave heat shields off from under the car (cause their LAZY and or messed up the shields with their monkey hands removing a tranny) and these are the IDIOTS that leave nice dents under your car because they don't know how to find a hard spot /frame / suspension pick up point to do a simple operation like jack a damn car up. These are the fellas who pried an oil pan off with a screw driver marring the aluminum block and denting the oil pan mating surface so it LEAKS. Assemblers know how to assemble an engine. Builders not only know how to assemble, but they know how to balance, clearance and torque down fasteners and know why these things are important. They also know what NOT to do in handling parts and / or assembling or disassembling them. You don't have to be a professional (pressional would imply you get paid and / or make a profession/make a living doing something) to be a "builder", you just have to know better.

And no, you don't need a Scud Missile to kill an ant, just step on it.



~Mike...................

 

ok gys got it done. thanks for all the imput here is a pic of how the engine project is coming out.

 

Purdy!! Those are small pics, but is that over spray alllll over the side housings side surface were the rotors' side, corner, oil seals etc. will be rubbing against? Looks nice and clean, just make sure to remove the paint from the wear surfaces, or it'll most likely clog up your sidr seal and corner seal grooves along with getting in your oiling system and over all messing a lot of stuff up.

~Mike.............

 

yeah i have to clean all the parts still. it will be clean before i put the engine back together but I still want to put a few more layers of the coating on it thats why I have not cleaned it yet. I'm going to Puerto Rico on Saturday and I'm picking up all kinds of stuff to put the engine back together. Rotary parts are a lot cheaper down there for some odd reason. I guess its for the high demand on parts but I could rebuild 3 engines buying the parts down there with what it would cost me to rebuild 1 engine buying the parts state side. but thanks for pointing that out thats good looking out.