RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   3rd Generation Specific (1993-2002) (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/)
-   -   Reusable engine parts (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/reusable-engine-parts-1109205/)

HobbeZ 01-06-17 07:00 PM

Reusable engine parts
 
https://cimg3.ibsrv.net/gimg/www.rx7...1a919005c3.jpgGuessing this housing is done for
https://cimg4.ibsrv.net/gimg/www.rx7...019a357bab.jpgBubbling in he water groove
https://cimg5.ibsrv.net/gimg/www.rx7...534a46c7ab.jpg
https://cimg6.ibsrv.net/gimg/www.rx7...4a3c5589c3.jpgApex seals were perfect
My first attempt at rebuilding a motor... engine came from a reman with around 50k but it's been sitting on and off For years.
I'm assuming my housing is toast.
As far as the intermediate iron there are rust bubbling up in the water seal groove.
Lastly the rotor apex seal groove seems chipped. the motor was pulled with good compression and all apex seals intact

OG BBF 01-07-17 10:28 AM

Housing is finished....you could use it as the damage is before where the inner water jacket seal sits, but I wouldn't expect to see many miles on the new engine if that damage gets worse. Water could accumulate between the inner and out jacket seals and cause issues.

iron looks fine just clean those seal grooves well.

rotor id measure the width of the apex seal slot, just make sure it's in tolerance but if that is OK then it's fine to use from what you've shown.

H_M 01-07-17 12:18 PM

I wouldn't risk the housing.

The iron looks like it just has build up in the grooves. Try cleaning it.

Check the clearances on the rotor. If the clearances are in spec then you can reuse it.

HobbeZ 01-07-17 03:31 PM

Thanks for the replies. Living in Hawaii parts come at a premium

freddyrx3 01-07-17 05:44 PM

You have many options.
1. Clean the grooves on the irons really really well with steal brushes. When reassembling, use 'High-Temp RTv Permatex silicone' instead of the traditional Hylomar or vaseline.

2. On the rotor housings, have an expert aluminum Tig-Welder make some nice beads to cover the corrosion-holes on the water jackets. Finally, have them machined back to a true surface.

3. If your rotors aren't within spec, you can also machine them to "oversized" apex Spec and use oversized Goopy Brand seals.

Good Luck with your build

7krayziboi 01-07-17 08:12 PM

Is that the front rotor ?

HobbeZ 01-07-17 08:20 PM

That was the rear rotor pictured.
Unfortunately where I'm located tig welding and local machine shops are far and few. haha unless someone in hawaii can chime in and refer me to one. but yah the part will just have get replaced for my piece of mind.

GoodfellaFD3S 01-08-17 08:10 AM

Coolant seal grooves like that aren't uncommon unfortunately. Looks like the engine was run with tap water inside it--- definitely not the recommended regularly flushed 50/50. Personally, for a performance build I don't like that damage to the apex groove, even if it specs out. In a pinch you could flip the apex seal so that the smaller piece is facing towards the center iron and away from that damage, but if it was me I'd be looking for a replacement. You can set the rotor inside the housing and you'll have a nice display for your office ;)

HobbeZ 01-08-17 02:35 PM

Is it me or has the FS section been sparse with good internal engine parts now days. I'm thinking about just buying a new motor and keeping on the side for a while.

RotaryEvolution 01-08-17 10:37 PM

your rotor housings are boned, mainly because you were lazy and used a rotary sander to clean them. you can't do that with these engines... the rotor housing sides should be treated like a cylinder head on a piston car.

in fact, all of your cleaning procedures are too aggressive with high speed tools.

HobbeZ 01-08-17 10:40 PM

i figured the housing was pretty done for so yah I used the small wire brush and a dremel to clean off all the crust on them. What would be your suggestion for cleaning the other "good" housing?

RotaryEvolution 01-08-17 10:43 PM

a sanding block is usually sufficient, as long as you sand the whole surface uniformly.

for the most part the intent is just to knock junk off the surface, going further than that just exposes the pitting and potential other issues. i used to leave anything in the pits undisturbed, wire wheels will dig everything out and leave holes. i sandblast housings now, but if there is moderate pitting i use metallic epoxy and level it with a razor blade before it cures. the filler material does not have to be aluminum, i have seen brand new mazda housings out of the box repaired in the same way i do it when they have a porous cast housing.

HobbeZ 01-09-17 12:26 AM

thanks for the heads up. i looked up that epoxy idea and found one of your old post like wayy back in the early 2000's

88SE_HI 01-18-17 06:36 PM

Nice to see that you still got your FD, also you could always pick up that $3k motor on craigslist.


All times are GMT -5. The time now is 02:52 PM.


© 2024 MH Sub I, LLC dba Internet Brands