2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

motor swap question

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Old Nov 12, 2004 | 07:36 PM
  #1  
Hex7E's Avatar
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From: St. Louis
motor swap question

I just did a motor swap. i am told the motor i put in my car ran well before he pulled it. apperently he left the trailing sparkplugs out of the motor while it sat for my gess is 6 months. after installing the motor at first with the starter turning the motor i got almost no compresion in both rotors. after putting some oil in the sparkplug holes and turning it a bit i got like 30 in the frount and 60 in the rear. (i dont have the tool to pull the thing out of my compreshion meter to check for each of the 3 rotor faces). I ran out of time to work on it more that day.
My question is if i keep working on puting oil in the combution chamber and spinning the motor should i get a usable compression or is this motor junk?
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Old Nov 12, 2004 | 08:18 PM
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Kingofl337's Avatar
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From: Manchester, NH
Try some ATF in there. Maybe that will help loosen up the apex seals. Good luck!
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Old Nov 12, 2004 | 08:21 PM
  #3  
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keep trying oil. safer. and lubricates it.
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Old Nov 12, 2004 | 08:21 PM
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From: Orange Park FL (near Jax)
The cranking speed makes a big difference in compression readings.
You must have a well connected & fully charged battery.

Hook up the fuel & spark and see if she starts.
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Old Nov 12, 2004 | 09:23 PM
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everyone shoots me down when i say this but it is true, the longer a rotary sits the lower the compression will be until it is re-broken in. add some ATF or oil to it and try to fire it up, the longer it runs the more it will seat up and raise the compression assuming it has no serious internal damage prior from sitting for so long, if that is the case then it is better to find out from just trying to run the engine rather than just assuming it has internal damage and tearing it down.

if/after you get it running try doing a search for ATF or water apex seal cleaning and do it to your motor, adding the initial bit of ATF helps the seals to move around freely but doing the process will clean most all of the remaining carbon off of them.

Last edited by RotaryEvolution; Nov 12, 2004 at 09:25 PM.
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Old Nov 13, 2004 | 01:53 AM
  #6  
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a cold motor will not get accurate compression readings. it needs to be a little warm for it to work properly.
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Old Nov 16, 2004 | 03:28 PM
  #7  
Hex7E's Avatar
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From: St. Louis
I tryed the oil, then MMO first, it didnt do much. Then i used atf and it did the trick. Thanks for your help.
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