EFINI-17

First off I just have to say this... I am a ******* idiot and should have never tried messing with the timing and fuel curve in order to adjust my idle so its smoother! Ok now down to business. I have an 84 gsl that blew all the rear seals in the rear rotor housing due to the following stated above. I need to get this car back in the road next monday, and am willing to invest all my time this whole week day and night to do so(starting tonight after im done writing this). What should I do? 1. Rebuild the 12a rear housing or 2. Swap in another 12a. 3. Swap in turbo 2 motor. Considering the fact that I only have 8 days which would be the fastest and most practical?

estrada42

Have you rebuilt a 12a before? Are you capable of doing so? Not to be rude, just questions I think should be answered. I bet it would be quicker and easier to swap in another working 12a. Rebuilding the 12a takes time and waiting for parts, and doing the work, then putting it in the car.

Put in the 12a, rebuild the old one and port it, when swap the new rebuilt ported 12a.

justint5387

iTrader: (1)

I think swap in another 12A would be fastest way. How did you blow your apex seal?

mazdaverx713b

iTrader: (91)

for time constraints, replacing the 12A with another running 12A would be your best bet to save time. to smooth out the idle, you can adjust the tps, the idle speed screw, and LASTLY,, the mixture screw. a lot of times, i would reccomend replacing the fuel filter and then rebuilding the carb before i went toying with the mixture adjust screw.

EFINI-17

I have rebuilt a 13b before, never a 12a. I think I am capable of rebuilding the motor but just swapping in a working one does seem like a quicker way... The only problem is that I live near chicago and dont know anyone that has a working 12a.... I know a 12a is not that much different then a 13b... Or am I wrong? Once again I BLEW the rear apex seals by richining up the mixture and advancing the timing to much... I thought I could get the car to idle smoother... Its a real shame because the motor had 110 compression on all faces of both front and rear rotors.... This really sucks. Oh well I asked for it. I guess the FD will have to wait an extra 2 months on top of the 10 months I already was going to wait. Man thank god that this week is spring break and I have a whole 8 days to fix my problem.

mazdaverx713b

iTrader: (91)

i'd post in the for sale/wanted section or the regional forum and ask if anyone in your area has a 12A for sale.

83rx7boy92

hey im just right up in racine maby when ur car is runnin again we can check eachother out or something....a few months ago i called around the yards lookin for parts but no luck....hopefully u can get it fixed

aa35199

iTrader: (1)

swapping is also alot cheaper, I was origianally going to rebuild, but if you tally the price it's very expensive (rotor kit, new bearings, having new bearings pressed, having the iorns lapped and mabey nitride coated, gasket set, specialty tools, port job since this will be the only time you can, and in my case new housings). I bought a JDM 12a from a forum member Japan2LA for only $450 with perfect 120 psi compression on both rotors. I had to swap alot of external parts from my old motor on it, but its a much better engine then my old one if I rebuilt it.

Black-83-Turbo

Well, I had a similar problem, caused by numerous Mountain drives of my '83 Arkay Aftermarket Turbo that bumped my little 12A from 100 HP up to 205HP! I had to find a shop - since I never worked on Rotaries before - only changed a Datsun 510 Engine! Found a Performance Shop in Burnaby, B.C. that does such cars for Races that did it for an excellent price - gave me another engine - swapped my rear housing so the Tranny would match, and did it for me in about a couple weeks (I was out of town - working in Construction, and they did it in two steps, with me coming to see it between, and make a decision.)

As to finding an avalable Engine for your car - try Atkins Rotary - Washington - URL: http://atkinsrotary.com/index.php?pag=0 Maybe they can get one express shipped out to you, or use their contacts to find one closer?

They list a number of engines with prices and core charges, plus Hours and Ph.# - here: http://atkinsrotary.com/index.php?pag=9
Best of Luck - Robert

Kentetsu

I've never heard of a non-turbo motor blowing due to richening the fuel and advancing the timing. Strange...

trochoid

iTrader: (6)

I was thinking the same thing.

EFINI-17

I also havent heard of this happening but hey! First time for everything right? . I already have the motor out and stripped to the block took me about 8 hours, ran into little problems. I am now out to buy an engine stand and flywheel puller with that massive 54 mm socket since I cant get it off. I am looking at the rebuild kits and yeah they are fairly expensive. I was woundering if I could just buy a set of apex seals and springs since thats all thats probably bad. I am hoping the housings are ok... Do you think I can get away with the old gaskets? They have 30,000 miles on them? I know it might be risky...

trochoid

iTrader: (6)

No, you need the gasket set at a minumum, coolant seals are not reuseable as they come apart with disassembly and the black ones, even if they are good, have grown after install and will no longer fit. Spec the apex seals, they may be good if you aren't looking for a long term engine. Replace ALL springs, these are critical in assuring good compression. Also strongly recommend new oil control o-rings.

You can order all of the parts seperately, but that gets more expensive. Your best bet may be to order the gasket kit and rotor kit from Atkins, that should suffice.

EFINI-17

Would apex seals, springs, and gasket kit due? I heard that cornerseals are reusable and I am sure the oil control seals are good because the car barely even puffed smoke on start up. The motor honostely was amazingly solid. Real shame what happened. When I crack the motor open tommorow I am going to post some pics of the Apex seals.

EFINI-17

Well i cracked my motor open yesterday and am dissapointed in what I saw. The first thing I noticed is that the rear rotor is missing all but one soft corner seal insert... I dont know if the motor was rebuilt without them or if they somehow got chewd up,,, The rear rotor and housing are garbage. The end plate and intermediate plate are questionable(i cant tell without a dial indicator...). Somehow one Apex seal is totally destroyed an the other 2 seem fine. Although the springs are badly bent... I now dont know if its worth rebuilding with my short time frame...

trochoid

iTrader: (6)

Those inserts are often gone, they seem to work thier way out or simply wear down, no biggie. That's why I use the solid corner seals now.

If you're going through the effort to rebuild, take your time and do it right the first time. It's much cheaper in the long run. I don't know if you have emissions testing, but this is an ideal time to do a little porting also.

When it comes to rebuilding and porting, I will not get in a hurry, small mistakes can have large costs attached to them. Each and every little detail during engine assembly is important. It's not a matter of measure twice and cut once, it's recheck one's work 3 times and make sure it's right. If you want an engine that will last, expect to lay out around 1k total in supplies and a couple weeks work for a proper rebuild and install, with porting.

EFINI-17

Anyone know how to take off the intermediate housing? I can only lift the eccentric shaft half an inch... I REMOVED EVERYTHING except for that plate that moves a little around the shaft...

trochoid

iTrader: (6)

Which end did you start at? Disassembly begins at the rear of the engine. If you started there, lift the e-shaft a bit, then lift/turn the intermediate plate. If you started at the front, put it back together and start over at the rear, after you've reread the FSM.