I took apart a running 85 12A b/c it had the leak of death and was just sitting there for tooo long doing nothing.

The rotor housings were SHOT w/massive flaking, but the motor ran fine before I pulled it.... so I used the rotor housings again anyways.

All the soft seals were replaced...
The corner seal springs were replaced with 3rd gen new guys...
The corner seal plugs were replaced w/ new guys...
The small triangular piece of the apex seals were replaced...
And everything else went back where it orginally came from.

I did a compression test on it and I'm getting 65 on each rotor...
too low..???
or should still start..??

I checked to see if I have the distributor in the right spot by using this thread:
https://www.rx7club.com/showthread.p...&highlight=TDC
and I think I do.

The wire method Jeff explains puts my L / yellow mark on the pulley slightly at the 1oclock positon, I backed up the yellow line to the pin and dropped the distributor in with the notches lined up. Sound right..??

Also, all my plugs are soaked with vaseline everytime I try to crank it b/c I think I used tooo much on everything. All I remember ringing in my head was "vaseline is your friend, you can't use tooo much of it" as I was putting this thing back together.

Everything else is dead on b/c I pulled another motor out that ran fine to try this one.

If someone can verify my TDC tribulations sound fine I'm going to try a pull start tonite.

 

i like to crank the motor without plugs (or fuel) until it builds oil pressure, this also spits a lot of the vaseline out.

step 2 is to hook up spark and fuel.

i've done a few of these type of rebuilds, where you're more fixing the oil leak, than rebuilding, and ive found it'll run the same as it did before

 

If that doesn't work, squirt a bit of oil in each rotor to help build compression. Having the car on a charger or jumped by another car can also help to make sure your cranking speed is up. If all else fails, pull start until she fires.

Before you do all this, first check everything over agian. Check for spark, make sure fuel pump is pumping, make sure fuel lines aren't crossed, etc. Once you know you are getting fuel and spark and are pretty sure timing is good, then try some of the options above.

 

I REALLY couldn't belive it, but my ignition cylinder's cranking position craped out on me last night. At least it became stuck in the "ON" postion so we were still able to take her for a pull start.

Even further to my suprise she actually started...!
and stayed running...!!
and sounded smooth...!!!
and held a idle after a few min...!!!!

The rotor housings had massive flaking.
I didn't clean a dammmm ounce of carbon off the rotors either.

 

So why did you rebuild it without fixing the biggest problems?

Also with 65 compression readings, youre looking at a blown engine fairly soon.

 

Because my SPANKY clean housings are going in my real motor.

And why would I blow soon...? That motor right there daily drove me for 2 years solid. I'm sure the flaking didn't happen overnight.

 

i drove one of mine for 2 years, and i pulled it apart to fix the leak, and the housings were worse!

it would even start on the first rotation of the motor if it was warm

 

I have torn down perfectly running 12As before and found that much housing wear or worse. When I built my 12A Bridge I went through 5 engines before I found a descent pair of housings. They will run for a long time with that much wear.

 

The wear on the housings isn't the reason it'll blow, its that compression number. Its getting pretty low.

And thats a reasonable explanation for re-using those housings lol