1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

getting used 12a engine - replacing question

Thread Tools
 
Search this Thread
 
Old Aug 31, 2014 | 09:33 AM
  #1  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
MN getting used 12a engine - replacing question

We bought a '81 RX7 and it turns out the front rotor was bad - no compression. It still runs/idles, but obviously not road-worthy.

I found a guy that has an car that the clutch went out and he doesn't want to fix it. For $250 we can get the engine. His engine is completely stock...all the emission stuff/solenoids/valves are still in place. It's completely stock. His engine also came out of an '81, but a GSL instead of an S.

Our car has all of that stuff removed, the Racing Beat intake manifold, a Holley carb (not Racing Beat).

I'm guessing we can just remove all of that stuff on the replacement engine to make it just like ours and it should work OK?

Anything else to be aware of?
Reply
Old Aug 31, 2014 | 10:23 AM
  #2  
luiml73's Avatar
Rotary Powered Boobies
Tenured Member 20 Years
iTrader: (1)
 
Joined: Oct 2001
Posts: 2,530
Likes: 0
From: Miami Beach
I would buy the engine for $250 open it up and build one solid engine using the best parts from both engines.
Reply
Old Aug 31, 2014 | 12:33 PM
  #3  
NCross's Avatar
I have a rotary addiction
Tenured Member: 15 Years
iTrader: (18)
 
Joined: Jun 2006
Posts: 4,815
Likes: 24
From: Columbia, Tennessee
Hes selling the car because he doesnt want to replace an $80 clutch? Laaaaazy.....
Reply
Old Aug 31, 2014 | 12:48 PM
  #4  
MosesX605's Avatar
My wife bought me 2 RX-7s
Tenured Member 20 Years
 
Joined: Aug 2001
Posts: 2,328
Likes: 3
From: Saskatoon, Saskatchewan, Canada
Originally Posted by NCross
Hes selling the car because he doesnt want to replace an $80 clutch? Laaaaazy.....
Yeah, that doesn't make much sense. Is the car for sale? I'd try to grab the whole shebang, myself.
Reply
Old Aug 31, 2014 | 06:33 PM
  #5  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
He's putting a 302 in it.

No comment......
Reply
Old Aug 31, 2014 | 06:37 PM
  #6  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
We pressure washed the engine today. Took the intake/carb off, took the bunch of hoses/solenoids off the top of the engine, took the air pump off.

It's nice 'cause the guy we got our car from rigged up an undersized electric fan. The new engine is all stock and still has the original fan. We'll keep that for now.

I have the original intake/carb if anyone is interested.
Reply
Old Sep 1, 2014 | 07:21 AM
  #7  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
Nothing special on the actual swapping of engines or clutch?
Reply
Old Sep 1, 2014 | 12:36 PM
  #8  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
I have the 5 17-mm bolts removed connecting the transmission to the engine, but it's not separating. It's sticking over by the starter area. Yes, I have the starter out.

I did not take the driveshaft or anything else related to the transmission apart - as the manual did not say to.

The top and passenger side of the engine/tranny are separating pretty good, but the driver side / starter area is not. Not seeing anything holding it together.
Reply
Old Sep 1, 2014 | 01:19 PM
  #9  
Jeff20B's Avatar
Lapping = Fapping
Tenured Member 15 Years
iTrader: (13)
 
Joined: Aug 2001
Posts: 15,725
Likes: 91
From: Near Seattle
There is a bolt under the starter you missed.
Reply
Old Sep 1, 2014 | 01:34 PM
  #10  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
I mistakenly loosened one of the long bolts holding the engine sections together. I found the bolt next to the starter and now have the engine out.

This is my son's car and he's paying for parts (limited budget). We're going to take the clutch off his old engine and put it on the replacement. I know, now is the time to replace it, but we're not going to.

Reply
Old Sep 1, 2014 | 02:22 PM
  #11  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
The car still has all of the air conditioning installed. The compressor turns fine. I'm wondering if it's worth it to try and get it working or just remove it.
Reply
Old Sep 1, 2014 | 04:35 PM
  #12  
erick31876's Avatar
turbo or bust
iTrader: (8)
 
Joined: May 2012
Posts: 870
Likes: 0
From: bristol,pa
how much do you want for the original intake and carb I'm interested
Reply
Old Sep 1, 2014 | 04:39 PM
  #13  
erick31876's Avatar
turbo or bust
iTrader: (8)
 
Joined: May 2012
Posts: 870
Likes: 0
From: bristol,pa
I would try to get the AC working you can get a retrofit kit to change it over to 134 a for 20$
Reply
Old Sep 2, 2014 | 06:12 PM
  #14  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
OK. I got the other engine in and started it up today. It's running on both rotors (unlike the old engine).

I put some oil down the carb, rotated the engine by hand and let it sit a while before starting it (it is a used engine, that was out of a car for a month or two).

Obviously it smoked really bad when I first started it up. After all the oil burned out, it stopped smoking. I took it for a spin and the first 3 blocks it didn't smoke at all, but on the way back, I started seeing blue smoke.

The OMP lines are connected to the Holley carb, but the OMP linkage is not. It's not a Racing Beat Holley carb, so there's no way to connect it to the carburetor. Whatever the state of the linkage is at rest is what it's in (not sure if it's at the rich or lean setting).

When the car cools off and you start it up, there is much less smoke. It doesn't seem to start smoking badly until you drive it or rev it up when just sitting there.

I've searched the forum and many of the threads mention either a bad turbo (we don't have a turbo) or bad oil seals. Is this something that may improve with the 'steam-clean' procedure with water in the engine, or a good hard drive to redline or just time? Or a rebuild only?

The car is running pretty good. No surging. Good power. No backfiring. No overheating. I believe good oil pressure (30psi at idle according to the gauge - and up from there).

Link to video of it idling after being driven 6-10 blocks
Reply
Old Sep 5, 2014 | 07:06 AM
  #15  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
Forgot to mention, regarding the smoking...in case it matters...

There is no catalytic converter. Pretty much straight pipe to a loud muffler at the rear of the car.
Reply
Old Sep 5, 2014 | 10:38 AM
  #16  
MosesX605's Avatar
My wife bought me 2 RX-7s
Tenured Member 20 Years
 
Joined: Aug 2001
Posts: 2,328
Likes: 3
From: Saskatoon, Saskatchewan, Canada
Well, once it's smoking like that for extended periods, there isn't much you can do.

A few ounces of Seafoam down the carb barrels may help clean the engine out, but that probably won't do much for the oil control rings. Heavier oil can reduce burning, so I typically ran 20-50 during the summer months in my old RX that had bad control rings and it helped somewhat.

The good news is that, aside from the smoke, the engine is idling pretty good and will probably last quite a while, provided you keep the oil levels up and the consumption doesn't get really extreme.
Reply
Old Sep 5, 2014 | 12:49 PM
  #17  
prophetjohn's Avatar
Tinker-tastic
Tenured Member 05 Years
iTrader: (1)
 
Joined: Aug 2013
Posts: 143
Likes: 0
From: U.P. Michigan
theres the small possibility that it could be residual oil left in the exhaust, a good hard run after its up to temp for a while would clear it out. my first engine did that for a while, but after about an hour of driving in and a few pulls to red line, it went away, if it doesn't a rebuild may be in order, but luckily it still drivable, and with thicker oil, should last a while, giving him time to save some money for a rebuild kit for the first motor!
Reply
Old Sep 7, 2014 | 05:51 PM
  #18  
rkhanso's Avatar
Thread Starter
Full Member
 
Joined: Jul 2014
Posts: 79
Likes: 0
From: MN
After driving it much more, the smoke level has dropped off considerably. I did use some Sea-Foam in the carb and the gas tank. Plus, some time at red line was fun.
Reply
Old Sep 9, 2014 | 07:16 AM
  #19  
wankel=awesome's Avatar
carb whisperer
Tenured Member 15 Years
 
Joined: Jan 2008
Posts: 1,485
Likes: 4
From: Greenfield, Ohio
My engine smokes like that when its very rich and im running premix.

A non-RB holley runs extremely rich at +4k rpm. Something to think about.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
Jul 1, 2023 04:40 PM
alphawolff
1st Generation Specific (1979-1985)
17
Nov 17, 2015 05:57 PM
Professorpeanutrx7
New Member RX-7 Technical
5
Aug 15, 2015 01:38 PM
KAL797
Test Area 51
0
Aug 11, 2015 03:47 PM




All times are GMT -5. The time now is 01:35 PM.