heywier427

Almost a complete rotary noob.

So, 12a n/a bridgeport.

Blew an apex seal this weekend.

Bought the engine fully bridgeported, and fresh rebuild, yada yada yada...

I would have thought when you bridgeport and engine, you at minumum put in 1pc apex seals.

What is the point of moving the powerband to 8k+ and only being able to rev to 8500 because of the 2pc seals???

Well thats what the po did, and I was thinking I had 1 pc in there. (there is no sending it back/refund).

Through all of the tuning (got an edelbrock avs650 to work flawlessly) I routinely brought it up to 9500 (9600 rev limit pill on trailing msd box, 9800 on leading).

The 2 pcs took a beating thats for sure, but they did not last. I have not put more than 500 miles on the car, but they were super hard miles!!

This thing just sings after 6.5k and pulls like a turbo till I take my foot out of it!


So, what to do???

It seems like Im not going to get away with rebuilding this thing for less than 1200.00 in parts (i can do the labor).

And thats with carbon apex seals, which are not good for the rotor housings (so I have read) and they last a most 20k. This car is a toy to beat on, so it will be seeing lots of high rpm fun time, so they may wipe out even earlier, or kill the housings.

Just by a cheap reseal kit and stock seals, and not rev past 8k? Have all the crappyness of a bridgeport, and none of the good? Does not seem at all worth it.

I just dont feel its worth it.

Buy a 13b and turbo it?

I know thats more cost than rebuilding this bridgeport, but there are more things to do when bridgeporting and reving past 8500 than just seals, and that adds up quick! It seems like a fuel injected 13b with no porting and a decent turbo is good for a few hundred hp. But how reliable if beating on it? I mean really ragging on it at the top of the rev range (where ever that may be).

I will not let myself spend 2k on ceramic seals, just for them to possibly break if I hit the rev limiter (read that can happen).

This engine is in a Datsun 510. Should i just go back to pistons? An sr20 turbo will safely make 350rwhp reliably with no internal mods.

I am liking the ability to rev to the moon, the noise, and the being different factor, but it just seems expensive and not all that reliable when it comes down to it.

Talk me into keeping it. I am a noob. I may be wrong in many/all points. Let me hear the good. What am i really looking at spending to reliably rev to 9500. Now that i know what that feels/sounds like, I really dont want anything but that

Thanks.

Tom.

FührerTüner

iTrader: (5)

You made your bed. Now lay in it.

heynoman

iTrader: (5)

Keep it. Rebuild it . Break it again . Rebuild it again . And then break it again. But seriously we can't convince you at the end it's your decision. Open the engine see what's needed and go from there. More then likely you need a new rotor and rotor housing . If your going to be Reving past 8500 used carbon apex seals and balance and clearance you rotating assembly.

heywier427

Come on.

I did not bridgeport this engine.

I am a noob. I did not realize bridgeports are kinda pointless.

I could care less about lying in my bed.

If a bridgeported engine really just sucks, than thats fine. I will get a 13b and turbo it, but will that work out to be crappy too.

I am a noob. Dont be a dick. Offer helpfull answers to a competent car builder.

The engine was damn near given to me, so I thought Id try it out.

heywier427

but am i correct in the associated costs?

approx 1200.00 per rebuild?

If a new rotor and rotor housing is needed everytime, it is really worth it?

1 seal and its springs are completely missing (viewed through the spark plug hole). So you think that would have killed the rotor/housing?

I really dont want to tear this thing down with out a plan, as making a half running car into a push car sucks.

heywier427

Are you saying "used" carbon apex seals?

What are the associated costs with getting the rotating asb. balanced/clearenced?

How long do housings last with carbon apex seals?

I just dont want to drop 2-3k and break it again.

Make a noob a list of what needs to be done to an na bridgeport with appox. associated costs, to safely rev to 9500, or what ever a bridgeport should rev to.

If i can spend 2-3k and have it last 20k of abuse, thats worth it to me.

Im not scared of putting out the money, its just I dont want to put it out every 1000 miles if theres a better way.

But also if i can spend 2-3k on 12a or 13b turbo,be more reliable and faster, I would rather do that.

Thanks.

heynoman

iTrader: (5)

Depending what the car is used for not everything on this list is needed. Rotating assembly balanced Rotor tip and side clearencing Carbon or ceramic apex seals Adjustable or modified oil pressure regulator mfr thrust bearings not necessary Eccentric shaft high flow oil jet not recommended if you using the car on the street. Mfr rotor bearings not necessary but have a deeper oil groove and extra clearance. Multi window or 3 window hardened stationary gears. All these thing will help but like stated not really necessary unless you plan on being at high rpm most of the time . I would just do a 13b swap and get it over with. Nothing wrong with the 12a but you might be better off with a 13bt swap .

heywier427

I know the oil pres. reg. has been modified already.

So balancing, bearings, stationary gears, and carbon seals + a rebuild kit and its reliable?

Car is only street use, but I speed

Since the rebuild is fairly new, can i re-use anything, or just go new every time?

I just like the simplicity/cleanness of a carb'd setup.

Although its much easier to tune with a labtop! I forgot how much tinkering went on with carbs!

If I were to go 13b and turbo it, do i have to do anything internally to the engine (other than maybe a standard rebuild)?

I know, "search noob!", but there is so much mis information out there.

Thanks.

heywier427

Does this look right?

Am I missing anything? What should my bearing quantities be?





IMG_1481 by thomas telesco, on Flickr

+ a few more gaskets.

Thanks.

heynoman

iTrader: (5)

The first step would be to take the engine apart and see what is still good. Since it's a recently built engine I don't don't see why you couldnt reuse anything that is still within spec. Not all 13b engines were na they also came turbo. If you can source one you can literally drop it in with the use of a handful of extra parts. Open the engine first see how trashed it is. The parts picture are correct . For street use its over kill but yes it will increase your reliability when Reving that high . especially if you plan on holding the rpm that high.

misterstyx69

iTrader: (142)

"Assuming" will cost you money.
Who know what has happened to the engine.All you know is that it is not Running..RIGHT?
Unless you are Ant-Man you can't see the internals of the engine to see how much damage there is!
STOP!!..crack it open THEN see what you need.
Do not go ordering stuff and find out you don't need it.

heywier427

Sounds good. Thanks for the responses.

I would not blindly order the parts, just want to get a budget figure together on making a reliable bridgeport or turboing a 13b.

I will tear it down this weekend and report back.

Love youtube!

Any hints/tips for tearing down? Other than vaseline !

Thanks.

Edit: Just bought another running 12a for cheap. Gonna swap it in so i dont have another dead car at the shop!

j9fd3s

iTrader: (3)

carbon seals are great on the rotor housings. they are very soft, and are a little bit self lubricating. housings always look great with carbon seals.

20k miles is such an arbitrary number, depends on how you drive. if you're running the daytona 24 hours, they last that race. if you had a stock Rx2/Rx3 which came with carbon seals, they go 60-80k miles.

but you should tear the engine down and see what is in it before you go and order parts

heywier427

I entered a $250.00 1996 vw golf in to the 24 lemons.

Went the whole 24hrs, and then swapped in into a mk1 vw and put a t3 turbo on it. I still have it as a shop rat, and it gets beaten on thoroughly. Its our loaner

Had a broken auto tranny when got at 250.00 swapped in a 5 speed, and off to the races.

Sucked out/changed the oil every driver change.

I hate working on freshly painted cars!!!!!!!!!!!!!!!! Swapping in the used 12a tomorrow night.

JZW

iTrader: (5)

If you like revving your car to upwards of 7k RPM (which you stated) then you are in the right place. No one can convince you to stick with rotary, you either love it or hate it. Are rotaries harder to maintain? My opinion is yes. But it all comes down to - Are you using new parts for your rebuild? Do you know a competent rotary mechanic? Reliable tuner? If you don't premix or know a reliable tuner you will blow an apex seal whether it is carbon or oem mazda.

crysis

how did you like those 500mi on the 510 with a 13b bridgeport? did it feel like melting babies while shredding on a guitar made of bones? if so, keep doing that. 13bt might be snoozey (probably faster, but won't feeeeeeeel as good).

My last two cars were a 15' evoX and an ap2 s2000. evo was way the **** faster but the s2k was just a different experience. I plan on doing a bridgeport 13b 1st gen one day

heywier427

Ok, so broke down the engine and these are my findings:

I do have 1pc carbon apex seals. I do not know the brand as they are not marked.

I broke 1 apex seal, and 1 side seal.

Apex seal was all but gone except for 1 small piece (the spring stayed in place). Corner seal was broken in 2 spots, 1 section was mia.

I feel everything looks pretty good as far as the housings and the rotors, but please chime in, as I really dont know. No scoring of the housing missing the apex seal So thats good. I see what looks like cross hatching. Is that good or bad? Pistons means good...I do not see any of the lifting chromoly on the housings or edges, but I dont think I see any chromoly anywhere? Let me know if you want a certain picture taken.

All the bearings show wear. Need the clutch needle pilot bearing replaced.

I had excessive smoke at start up and more than "normal" on hard acceleration, but the oil control rings are all brand new (green) and are springy. It was on the cylinder with the now broken apex seal, as the spark plug was always wet with oil. Should I just change em? What else would cause the large amounts of smoking on start up?

My timing was at 26/18, why would the apex seal break? An n/a shouldn't be able to detonate that badly.

Always premixed 1/1

Thanks.

Oh, and the "engine builder" painted inside all over the engine. Even the oil pan! There is paint flaking everywhere!!! Stupid mf'er!

IMG_1488 by thomas telesco, on Flickr

IMG_1487 by thomas telesco, on Flickr

IMG_1491 by thomas telesco, on Flickr

IMG_1490 by thomas telesco, on Flickr

IMG_1492 by thomas telesco, on Flickr

Had to make 2 posts. See more pics below.

Let me know what ya'll think.

My list is:

clutch pilot bearing
oil pan gasket
timing chain cover gasket
intake man gasket
engine bolt seal washers
1 apex seal (can you only buy one?)
1 side seal
all bearings
water seal kit
oil control rings (maybe)
exhaust gasket.

Any others you can think of?

Any other modifications I can do now that the block is torn down?

Any reason why the bridgeport wasnt fully extended?

Thanks.

heywier427

IMG_1493 by thomas telesco, on Flickr

IMG_1495 by thomas telesco, on Flickr

IMG_1494 by thomas telesco, on Flickr

IMG_1496 by thomas telesco, on Flickr

IMG_1497 by thomas telesco, on Flickr

IMG_1498 by thomas telesco, on Flickr

IMG_1499 by thomas telesco, on Flickr

IMG_1500 by thomas telesco, on Flickr

IMG_1501 by thomas telesco, on Flickr

IMG_1502 by thomas telesco, on Flickr

IMG_1503 by thomas telesco, on Flickr

fidelity101

iTrader: (11)

If you are spinning it that high all the time, I would balance your rotating assembly if it is not done so already.

heynoman

iTrader: (5)

You can buy just one Carbon seal no prob . But I would make sure the rest are still usable and not chewed up or improperly clearances. The port on that engine look bad fairly sloppy . I can't see the exhaust ports but I would check them out and make sure they do not have sharp edges. Some of the side seal look like the tips are getting chewed up. Honestly I think it might be cheaper in the long run to just start with a new engine . I think the builder didn't care to much about the engine. If he didn't care enough to mask it right before painting he didn't care enough to make it reliable and make sure it was working specs.

TonyD89

iTrader: (10)

It's hard to see but in the last pic of post #17, it looks like the port goes in past the oil control ring circle.

heywier427

Thanks for pointing that out, as i would have never known.

Yes, it definitely looks like that the port protrudes into the oil ring mark. This is the smoking "gun" ?

IMG_1510 by thomas telesco, on Flickr

Exhaust ports:

offending housing

IMG_1509 by thomas telesco, on Flickr

IMG_1508 by thomas telesco, on Flickr

The po was the typical lower end of the spectrum rotary owner, so Im not really surprized. Probably the reason the engine was super cheap. I know he did the work himself.



Do you think the edges of the exhaust ports are too sharp? Can i just give em a bevel?

Do you guys all feel this thing is pretty shot.

If its not worth saving, Im going to open the ports up something feirce, and add 200 shots till it really gives out

If this is shot, can i weld up the area that is cut into the oil ring, and re-machine.? I have access to a milling machine.

About the rotating assembly. I was under the impression the 84-85 engines (which is what this is) had the lighter 26lbs. flywheel. The one I have weighs out at 31, which is the older stuff. Is there a way to date/ID my rotors/front balance? Maybe the whole asb. is older? It did not vibrate. I had a rotary owner up my way drive it, and he did not mention anything amiss.

Thanks again for all the info.

At least its down for the winter time!

heynoman

iTrader: (5)

You can bevel the edge of the ports I can't really tell from the pictures. You can't open the ports up to much more otherwise you will hit water. I never recommend welding on the irons plus it doesn't look like he ported to deep into the ocr groove in the last pic . Make sure that the springs are on the correct sides of the rotors .if you post some pictures of the rotating assembly I can help you identify it.

heywier427

So by my eye, I do not see the oil rings (the actual green seal anyways) when I turn the rotor to its fullest part of the port. Nor do i see the edge of the control ring. I definitely see the machined silver edge though.

What if the side seal had always been broken(since i got the engine)? It was broken in 3 pcs. and only 1 of them was missing. The missing section is aprox. 5/8" Is that enough to run mildly ok, but have a good amount of blow by? Seems logical. Smoke was very blue and heavy upon start up and tapered off to a super light blue haze. Sometimes it was gone, sometimes it was there.

Again, always'd premixed and always on the heavier end of 1/1. Supertech blue stuff from walmart.

IMG_1522 by thomas telesco, on Flickr

IMG_1523 by thomas telesco, on Flickr


rotor with broken side and apex seal:

IMG_1515 by thomas telesco, on Flickr

IMG_1516 by thomas telesco, on Flickr

Other rotor:

IMG_1517 by thomas telesco, on Flickr

IMG_1518 by thomas telesco, on Flickr


IMG_1519 by thomas telesco, on Flickr

IMG_1520 by thomas telesco, on Flickr

IMG_1521 by thomas telesco, on Flickr


Offending exhaust port:

heywier427

IMG_1524 by thomas telesco, on Flickr

IMG_1525 by thomas telesco, on Flickr

IMG_1526 by thomas telesco, on Flickr

Middle iron, side of the broken side seal:

IMG_1527 by thomas telesco, on Flickr

IMG_1528 by thomas telesco, on Flickr

IMG_1529 by thomas telesco, on Flickr

IMG_1530 by thomas telesco, on Flickr