rotor housing defects from factory?
#1
rotor housing defects from factory?
has anyone noticed these on rotor housings before? these are new ones still in wrapping. its looks to me that there were large defects/pits in the housing that have been patched with some kind of translucent-dark filler.
front
rear has 1 tiny patch. and what is the bagged rubber ring/plug thing? i don't remember seeing it during teardown.
front
rear has 1 tiny patch. and what is the bagged rubber ring/plug thing? i don't remember seeing it during teardown.
#3
yeah they were sold as new, which is complete bs. i received the boxes with the tape seal broken. so someone hand picked me defective housings maybe?
i did find a old post about having a engine fail soon after rebuilding because this defect. post #6 https://www.rx7club.com/showthread.p...+housing+epoxy
i did find a old post about having a engine fail soon after rebuilding because this defect. post #6 https://www.rx7club.com/showthread.p...+housing+epoxy
Last edited by sevensix; 09-17-07 at 01:50 AM.
#5
Rotary Freak
I found those rubber plugs as well in my package and figgered they were meant for the oil jets. Looking at my old housings I didn't find any so decided not to use them with my 93' oil jets
#6
ERTW
iTrader: (4)
I've actually seen this a number of times in the past even on rotor housings purchased from Mazda. For some reason, I also found a large number of Mazda reman engines with this issue. While exposed porosity on machined castings is not uncommon, you'd think they'd find a better way to fill those pits. I agree, you have every right to demand an exchange, but if the situation were different and you were stuck with housings like that, the pits could be easily filled by an experienced welder. I've had great success salvaging such housings.
Trending Topics
#11
I've actually seen this a number of times in the past even on rotor housings purchased from Mazda. For some reason, I also found a large number of Mazda reman engines with this issue. While exposed porosity on machined castings is not uncommon, you'd think they'd find a better way to fill those pits. I agree, you have every right to demand an exchange, but if the situation were different and you were stuck with housings like that, the pits could be easily filled by an experienced welder. I've had great success salvaging such housings.
Originally Posted by glenrx7
We at AZ Rotary Rockets buy direct from Mazda and they have sent us housings like this. So, yes these are factory, dont worry about it they will work fine...
#12
its been over a week and no word from rhdjapan. in the past they were always fast to respond when i had questions. now a big problem comes up and they start acting guilty and ignore. i'll keep the thread updated if i hear back from them later like if they've overlooked my emails or are working on it w/o notifying me.
#14
ERTW
iTrader: (4)
Usually no more than $20. I have access to a milling machine, so I take the high spots down and finish the last .005" off with a fine file. Aluminum is easy to work with, so you can file the entire weld down with a file. Regarding the claim that having epoxy in those pits is as good as having no pits at all, I'd say that in the long run with the different expansion rates of epoxy vs. aluminum, it would come back to bite you in the ***. It may be fine for a while and the engines that I've seen this on didn't always have a coolant leak. I elected to fill the pits because I'm ****.
#15
TANSTAFL
iTrader: (13)
Usually no more than $20. I have access to a milling machine, so I take the high spots down and finish the last .005" off with a fine file. Aluminum is easy to work with, so you can file the entire weld down with a file. Regarding the claim that having epoxy in those pits is as good as having no pits at all, I'd say that in the long run with the different expansion rates of epoxy vs. aluminum, it would come back to bite you in the ***. It may be fine for a while and the engines that I've seen this on didn't always have a coolant leak. I elected to fill the pits because I'm ****.
Unless there are huge areas of jb welding done, expansion shouldn't be an issue. The smaller the amount, the smaller the change in size.
#16
Racecar - Formula 2000
If they used aluminum-filled epoxy (which it seems to me they would do), the expansion coefficient of that would be very similar to plain aluminum. This is due to the fact that the modulus of epoxy is much lower than the modulus of aluminum. Therefore, since the epoxy just binds the aluminum particles together and to the interior of the hole, the aluminum would (mostly) control the expansion coefficient.
#17
well seems like the word from mazda japan and amemiya is that i should use these housings and my engine will be fine. so i'm going to take my chances and watch for coolant issues, if it fails i'll get them aluminum welded. i have a 2nd car and im doing the engine work myself so it will just be a few more days of work if this is the case. im not too comfortable with having the welds done at the moment or my own ability to get the weld/surrounding area prepped to spec.. so it will be the back up plan.
thanks to rhd for getting back to me the past 2 days with their quick communication.
dave im not sure what the epoxy is made of but it doesn't look like aluminum to me, although im only saying this bc the stuff is brown and not shiny
thanks to rhd for getting back to me the past 2 days with their quick communication.
dave im not sure what the epoxy is made of but it doesn't look like aluminum to me, although im only saying this bc the stuff is brown and not shiny
#19
Registered Loser
Join Date: Jan 2005
Location: South Carolina
Posts: 174
Likes: 0
Received 0 Likes
on
0 Posts
with the rotor housing the cast gets air in it thus having holes in it, it seems mazda could have had a better vacuum casting system made for their engines. I dont think those will hurt the engine just sucks... the quality looks chinese.
Thread
Thread Starter
Forum
Replies
Last Post
cdn
2nd Generation Specific (1986-1992)
14
09-10-15 06:23 AM
cdn
2nd Generation Non-Technical and pictures
0
08-11-15 08:59 PM