Bstrickler

Are the corner seals (12A) re-usable, or no? I'm just wondering, that way I'll know whether or not to throw out the extra corner seals I have when I rebuild my spare 12A.

Bstrickler

Plus, what's the difference between solid corner seals, and OEM ones?



here's pics of what I'm talking about:



Solid:





OEM:







Are the solid ones stronger than the OEM ones, or something? And what are the pro's and con's of each?

j9fd3s

oem seals are designed to be a little springy, they should seal a little better, live a little longer.



the solid seals, which also are oem, but mazda stopped using em, prolly are a bit stronger.

Lynn E. Hanover

I have used both styles. The only corner seal to fail in use was the later rubber plug style. Not as strong as the solid style. Also the rubber plugs get hard and shrink. Some vanish in us making me wonder how they got away, and where they went.



I only use the early solid seals and late flat springs. Work great. Never break.





Lynn E. Hanover

Bstrickler

So, Lynn, you're saying go with the solid seals, and the flat springs?

Lynn E. Hanover

Thats it.



For slow street only the newer rubber plug things are better for emissions, but that is not why we are here. The solids I reuse over again through many rebuilds. They are powdered iron with a flash chrome plate. Very good, (stock) from Mazda.



I chamfer the sharp edges with a diamond file before installation. I think (with no evidence at all) that it is more likely to use any oil film as lubrication rather than scrape it off. Also, you can break a bridge in a bridgeported engine and not know it until rebuild. So if a discontinuity developes at the break, the chamfer may help prevent damage to the corner seal. The chamfer is microscopic so as to limit leakage around the seal.





Lynn E. Hanover

Bstrickler

Okay. I'm working on figuring out about how much it would save us to buy all the parts to do a rebuild ourselves, versus paying someone to rebuild it, that's why I wanted to know.



Plus, do I buy the corner seals for the 93-95 RX-7? Those are the only one's I can find that are the flat springs.



If/when you find out how well chanfering it works, tell me, so I know if it works, if I haven't done a rebuild by then. I'm not looking at porting my engine yet, I'm quite content with the power it has/will have once I'm done fixing it up.

j9fd3s

you want the fd corner seal springs. NF01-11-C24



cant find the number for the solid corner seals, its something wierd 1078-11-321? i dunno

Lynn E. Hanover

Well, if you get it assembled for less than a grand, that would be the lower limit for a good build.



If you had done all of the preassembly stuff, like trim the side seals and provide sterile components so my hands don't get dirty.



If I do it (and I won't anymore) and I clean the parts, trim the seals and rebuild it all with no porting at all.

Its 3 days at 65 per hour. So a rebuild with all clean parts is way cheaper.



Once you have someone walk you through it once, you can build one in 2 hours complete, if you start with clean or new parts and the seals trimmed. That is for bone stock street engines. It is an honor for somebody to pay me to do a street engine, but there is no joy in it for me. Anyone can do it.



The problem for the builder is that control of the support systems is out of our control. Control of use, temps, RPM and so on. If there is a problem, it won't be blamed on 16 missed shifts with revs to the moon,

it will be that shitty engine that so and so built for me. If the car has been running up front and just needs a fresh or spare engine, then there is seldom a phone call for other than a thank you.



If the car has never been successful, there will be problems. Cars that are never fast can have poor cooling and oiling systems and never have a problem. Then comes the new engine from "whats his Name" and the damn thing over heats all of the time, and is hard to drive off the corners. (that is called wheelspin limited **** for brains). We can't get it to idle under 2,200 RPM???? Really??? you wanted the biggest "J" bridgeport I could build, and now the damn thing won't idle down like the IT (stock engine) car you drove last year. Damn.



And it does no good at all to tune it on the dyno, leave it on the rich side and ship it off with instructions to not touch the distributor or the carb. When you show up at the track to help those people you will not recognize that engine. They will have changed everything but the paint.



So, I don't need it. Do it yourself. Find somebody close on the list who does it with some regularity and get them to show you how. Stop by here and I will show you or anyone how. This month I will be heading out to show two different locals how to go through the whole deal, no charge. The driver retired to help his son race a Miata (gag) it has pistons......and the race cars are for sale. Got a call tonight already.

I am retired, and have plenty of time to kill.



Buy the tape. Buy a manual and do it yourself.



Lynn E. Hanover

j9fd3s

if i can do it, anyone can!