well i just got a 1987 mazda 13bFI from a junk yard. it has been sitting since about 2000 or 2001 and i was wondering how to do a proper test to see how good of shape the motor is in. i have a compression gauge and i was wondering how exactlyi would do a compression test on it.. and will the compression get better being as though the motor has sat a while. i have heard that if a rotary sits a while it will loose compression.. but after you start them and run them after they have sat it will like reseat the apex seals or something like that. i am planning on putting the motor in my 1982 rx7. the odomter on the wreaked 87 showed 225,000. it also had a bran new cluthch and pressure plate. and i couldnt see somebody putting all that money into a pile of sh*t motor. and help would be great. thanks

Rob

 

well i just got a 1987 mazda 13bFI from a junk yard. it has been sitting since about 2000 or 2001 and i was wondering how to do a proper test to see how good of shape the motor is in. i have a compression gauge and i was wondering how exactlyi would do a compression test on it.. and will the compression get better being as though the motor has sat a while. i have heard that if a rotary sits a while it will loose compression.. but after you start them and run them after they have sat it will like reseat the apex seals or something like that. i am planning on putting the motor in my 1982 rx7. the odomter on the wreaked 87 showed 225,000. it also had a bran new cluthch and pressure plate. and i couldnt see somebody putting all that money into a pile of sh*t motor. and help would be great. thanks

Rob

 

well i just got a 1987 mazda 13bFI from a junk yard. it has been sitting since about 2000 or 2001 and i was wondering how to do a proper test to see how good of shape the motor is in. i have a compression gauge and i was wondering how exactly would do a compression test on it and what should it be at.. and will the compression get better being after it ahs ran being as though the motor has sat a while. i have heard that if a rotary sits a while it will loose compression.. but after you start them and run them after they have sat it will like reseat the apex seals or something like that. i am planning on putting the motor in my 1982 rx7. the odomter on the wreaked 87 showed 225,000. it also had a bran new cluthch and pressure plate. and i couldnt see somebody putting all that money into a pile of sh*t motor. and help would be great. thanks

Rob

 

i really need help on this if somebody could find it in there great knowlege...or is everyone to good to answer.. i know the question might be stupid to some of you but, i need to know. thanks

 

You could always hook up a starter, if trans avail, to check compression. Even though engine cold, anything above 90 good. Your just looking for equal pulses. Turn it over by hand also, and see if pulses. A lot of times if rotaries sit with weak, sticking springs, you'll need to build compression with oil,atf, mmo whatever.