is my cranking speed fast enough for an acurate compression test. **video**
#1
is my cranking speed fast enough for an acurate compression test. **video**
Cause if it is then my computersion is on 90 cold!
Please watch the video and let me know what you think. I hope it's not time for another rebuild ![Frown](https://www.rx7club.com/images/smilies/frown.gif)
http://media.putfile.com/cranking-speed
![eek](https://www.rx7club.com/images/smilies/eek.gif)
![Frown](https://www.rx7club.com/images/smilies/frown.gif)
http://media.putfile.com/cranking-speed
#6
I think I counted me cranking right there for 6 seconds and i think I heard 20 rotations so that would be 200rpm witch I believe it's supposed to be 300rpm. Also what is it usually more compression when cold or when warm? I always thought it was more when cold but then I've heard more when warm from a few people.
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#13
ok I just added a big 4 gauge ground wire from the battery to the frame and still it was cranking slow so i descided to put everything back so I could drive the car over to a budy of mine that has a mazda starter. Well after I put everything back it cranked quicker than it ever has
so anyways after that i was like wtf so I descided to take one thing off at a time to find out when it starts to crank slow. Well I took the egi fuse out and still cranked fast then i took the wires off and it still cranked fast and then I took out one spark plug and when I did that it started to crank slow again. Whats the deal!!!!! Thanks.
edit: ok well I found that if I plug that one hole up with the compression guage it cranks fast but I thought you where supposed to have both spark plugs out? Anyways the leading only has 90psi cold so i'm figuring something fucked up in the rebuild and i'm going to have to rebuild the motor again.
edit: front has 100psi.
shitty shitty shitty, I guess I need new housings or something.
![Dunno](https://www.rx7club.com/images/smilies/dunno.gif)
edit: ok well I found that if I plug that one hole up with the compression guage it cranks fast but I thought you where supposed to have both spark plugs out? Anyways the leading only has 90psi cold so i'm figuring something fucked up in the rebuild and i'm going to have to rebuild the motor again.
edit: front has 100psi.
shitty shitty shitty, I guess I need new housings or something.
Last edited by hondahater; 04-23-06 at 11:49 AM.
#14
this is what rotary resurrection says to do:
Compression test using a piston engine tester:
1. note battery strength. A weak battery will yield low compression results.
2. Remove both lower plugs and wires.
3. remove EGI fuse from engine fusebox.
4. have a friend floor the accelerator pedal, opening the throttle for more airflow
5. insert your tester into the leading hole
6. hold the valve on the side of the tester open
7. have your friend crank the car over for 5+ seconds.
8. observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range.
9. let out on the valve now, and let the tester reach an overall compression value for all 3 faces(highest of 3 will be displayed). 115+ is like new, 100-115 is healthy, 90-100 is getting weak(1 year or less in most cases) below 90 could blow at any moment.
10. repeat for opposite rotor. Note difference in overall compression between rotors, which should be no more than 20psi max
I can't take out both spark plugs or it will crank slow. If I only take out one leading sparkplug and fill it in with the compression gauge then it cranks fast. Whats the deal with this and will it still give me an accurate reading doing it this way.
edit: I ment in the last post that front has 90psi and rear has 100psi
Compression test using a piston engine tester:
1. note battery strength. A weak battery will yield low compression results.
2. Remove both lower plugs and wires.
3. remove EGI fuse from engine fusebox.
4. have a friend floor the accelerator pedal, opening the throttle for more airflow
5. insert your tester into the leading hole
6. hold the valve on the side of the tester open
7. have your friend crank the car over for 5+ seconds.
8. observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range.
9. let out on the valve now, and let the tester reach an overall compression value for all 3 faces(highest of 3 will be displayed). 115+ is like new, 100-115 is healthy, 90-100 is getting weak(1 year or less in most cases) below 90 could blow at any moment.
10. repeat for opposite rotor. Note difference in overall compression between rotors, which should be no more than 20psi max
I can't take out both spark plugs or it will crank slow. If I only take out one leading sparkplug and fill it in with the compression gauge then it cranks fast. Whats the deal with this and will it still give me an accurate reading doing it this way.
edit: I ment in the last post that front has 90psi and rear has 100psi
Last edited by hondahater; 04-23-06 at 12:06 PM.
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