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I’ve got a 13b center iron and the walls of the coolant groove passage have spots where they kind of curve in towards the water jacket slightly, what does this mean, is this reusable?
any help is appreciated, pictures are coming soon thanks guys
In the picture it looks like the side housing has failed between the coolant passage and the coolant seal groove.
See how the side seal groove shoulder bulges out into the coolant jacket?
This is the common 2nd gen side housing coolant failure mode
New center side housing required.
The bonus question-
Inclusions in the rotor housing sealing surface must be cleaned, filled and made flush before assembly.
Even Mazda appears to have a process for treating any knick or inclusion on brand new rotor housings on this sealing surface. I see black pen marks at the site of tiny epoxy filled crevices in these areas on Mazda crate engine taken apart.
The center side housing is to be recycled for scrap iron.
Clean the rotor housing well at the pitting, apply JB weld and skim it flat with a razor blade.
Once dry you can wetsand the sealing surface with 600grit and a FLAT surface. Dont just work that area, glide the 600 grit glued to flat surface (piece of plexiglass works well) over the whole rotor side evenly and without pressure.
You are just gently removing any high spots- not removing aluminum. Clean thoroughly when done to remove any grit.
Alright, thanks for your help, I might have it silicon bronze welded and refinished ive heard decent things about the process and it keeps more parts in circulation.
You need to make sure you dont remove aluminum from the sides of the rotor housing. None.
If (while) the JB weld patches are higher than the aluminum cover the aluminum around the JB weld with scotch tape.
Then use a small piece of hard flat material like plexiglass or metal and stick part of a self adhesive orbital sanding pad to it. Something like 400-600 grit.
The sand paper has to be stuck to the backing plate and not hanging over. You cant have the sand paper accidentally drag over anything.
Carefully sand the JB weld down checking constantly that the tape protecting the aluminum is still on it and you arent sanding the tape.
Once the JB weld on all such spots is down to the level of the tape, you will have to take the tape off and try still to just sand the JB weld patches.
That was your practice, this is the main event.
Use 600-1,000 grit for this and again the sand paper must be securely stuck to the backing plate with none hanging over. You really cant let the sand paper drag where you dont want it to.
Use water for this step and small circular motions on the JB patches stopping to make sure you arent sanding Aluminum.
The JB patches should be flat and in the plane of the aluminum at this point, so just exert even pressure on top of the JB weld.
Once you feel you have all the JB patches just level to the aluminum, clean the surfaces and then drag the finest grit paper stuck on its flat backing all along the rotor housing side following its circumference with even speed and pressure once and verify its all flat.
You are looking for fine sanding scratches all in the direction of travel around the rotor housing circumference wheras the previous fine scratches were circular on the JB weld areas and (hopefully) very little to none on the adjacent aluminum.
