Hi guys,
First i screwed up my port, then i picked up a new center and now I am worried about pitting of the water seal groove "floor" this is the outer groove and minor pitting on the inner floor as well. Please see pictures.

 

normal, don't worry about it.

 

Thank you! I was starting to lose sleep over it! Theres also a few small nick on the mating surface should I worry? its right in the center between the two O ring grooves. Do I need to fill it in with anything?

 

The pitting is very common. The o-ring will seal it up fine. Also kind of the purpose of using something like Hylomar on the o-ring.

These days it's hard to find irons without any pitting. Rotor housings too. I used to fill the pits with epoxy and then sand it smooth but have since determined that is pointless.

The mating surface isn't a sealing surface, so no worries.

 

yep, neither of it is any concern unless one is gouged and will allow coolant to pool into where the tension bolts go through the housings. the bolts will corrode if coolant gets in there, the tension of the bolts actually seal up those areas otherwise.

i used to also epoxy small pitting in the housings and abandoned it to just apply a small amount of silicone to the mating surfaces prior to assembly. this used to also render OEM coolant seals only 1 use, of which i also abandoned and no longer use OEM multi piece coolant seals.

 

So I dropped by racing beat and according to their engineer he doesn't not recommend using it :/ trix sold me this piece and said its fine... Really don't know what to do now. Maybe I'll take a video of the details of the pitting or is it really fine? So many builders so many opinions! Then again whatever Aaron and Ben says is golden!

 

I bet he recommended that you just buy one of his nifty-near-2000 dollar aluminum ones too!

 

Lol!!

 

I'll put it this way: I had exactly the same pitting on my Project Tina engine when I built it all those many years ago.

It's just going to be VERY hard to find an iron without pitting these days. All these parts are old, and have been filled with coolant ever since they were made.

RB and Mazdatrix need to keep very high standards when giving advice because they don't want someone saying "Well, Mazdatrix said I could use it but then my engine broke!". Us in the real world who are just giving advice knowing what people have to work with in their garage understand that parts can't be 100% all the time. Frankly, irons can be pretty damn rough and you can still end up with a wonderful engine. It's the condition of the housings and rotors (apex seal grooves!) that makes the difference.

 

most of the engines i build are second gen engines, approximately 70% of around 200 engines is 140 engines. out of those 140 nearly half of them had identical pitting in the grooves, of that 140 about 20% had pitting at the edges of the coolant seal groove.

out of those 140 engines i have only had 1 come back with a failed coolant seal due to a wall breaking or the coolant seal not holding, this includes engines that are now over 10 years old... not a great selling point for my new product but even that one engine i warranteed, if it made it out of warranty would have been another needless $1000+ rebuild.

out of those 200 engines NONE have ever broken an outer coolant seal wall or had external leaks. issues are always with the inner coolant seals and their related walls. most pitting is on the exhaust side due to the heat generated in that area, still does not mean anything.

 

Great advice and thanks for the piece of mind. I do have a perfect condition s5 turbo center housing. Is there a way I can make it work? if I just leave off the EGR how would i prevent an exhaust leak.What all do I have to do to use a S5 center with an S4 n/a.

 

peace**

 

just mock up a piece of aluminum box metal and pound it into the rectangular opening. i think i used a piece of u-shaped aluminum trim from home depot because it matched the depth and opening width perfectly. if it doesn't fit just right you can always fill the gaps in with JB weld to seal it up.