rebuilt engine
#1
rebuilt engine
i just rebuilt my rx8 engine... doped it in... and car dos not start...engine is flooded by now with all that fuel that went in
it has nice even pulse... but when i hooked up piston engine compression tester didn't get much of a readout -0psi
is this normal for fresh rebuilt engines ...all new seals,springs, bearings..........
here is the link to a video of engine pulsing without spark plugs
http://youtu.be/qJtqkvoVjO8
it has nice even pulse... but when i hooked up piston engine compression tester didn't get much of a readout -0psi
is this normal for fresh rebuilt engines ...all new seals,springs, bearings..........
here is the link to a video of engine pulsing without spark plugs
http://youtu.be/qJtqkvoVjO8
#2
is the rebuild just bad or the seals need to brake in
nothing fell out of the engine or broke so everything is in place
apex seal look to be moving and no stuck
could stuck side seals be the problem
or the the housings that i reused
which didn't look to have much where on them
nothing fell out of the engine or broke so everything is in place
apex seal look to be moving and no stuck
could stuck side seals be the problem
or the the housings that i reused
which didn't look to have much where on them
#3
after adding bit more oil rear rotor started making compression 30psi
front still didn't make any compression puled the engine out
when i was taking LIM of i noticed that the gasket was folded up and it was blocking primary intake port on the front iron ..don't know how that happened but could that mess with compression numbers in the front housing...
front still didn't make any compression puled the engine out
when i was taking LIM of i noticed that the gasket was folded up and it was blocking primary intake port on the front iron ..don't know how that happened but could that mess with compression numbers in the front housing...
Trending Topics
#8
Rotary Power
iTrader: (15)
have you done the whole deflooding process on it as well, if you smell alot of gas coming out the exhaust it could be flooding, sometimes it will take a while for the engine to build compression, have you made sure that the car is getting proper oil pressure ? it takes a bit of cranking over before the oil will fully get through the entire system, i know this because it took a while to get my 2nd gen rx7 started.
as far as the whole low compression, if there is no compression building, there must be compression leaking out somewhere. you should be making minimum 90 psi (and that basically on an engine thats ready to die) , good compression on a rebuild would be like 120+ pretty much you want at least 100+ , depending on the wear of the rotors and housings and quality of rebuild youll have more.
as far as the whole low compression, if there is no compression building, there must be compression leaking out somewhere. you should be making minimum 90 psi (and that basically on an engine thats ready to die) , good compression on a rebuild would be like 120+ pretty much you want at least 100+ , depending on the wear of the rotors and housings and quality of rebuild youll have more.
#9
Rotary Power
iTrader: (15)
here you go bro, your 30 psi reading could be because you did the compression test wrong, heres how to do the compression test, quoted from kevin landers / rotaryresurrection.com
NOTE - This guid designated For 2nd generation rx7s not rx8s, so everything may not be the same. But the theory is still the same.
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.
NOTE - This guid designated For 2nd generation rx7s not rx8s, so everything may not be the same. But the theory is still the same.
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.
#10
yea low compression numbers where do to battery and starter only turning engine at 150rpm instead of 250 rpm needed for the proper compression test or a Mazda compression tester that calculates all this stuff for you based on the rpm
problem was combination off stupid lil mistakes...rushing working late in to night...folded up gasket not letting any air in to front rotor...i had another gasket on hand so no big deal...switched some spark plug wires around- coil was connected to proper spark plug --- just the length or the wire was wrong
all sorted out,,, i have been driving it... about 500 miles on it now
problem was combination off stupid lil mistakes...rushing working late in to night...folded up gasket not letting any air in to front rotor...i had another gasket on hand so no big deal...switched some spark plug wires around- coil was connected to proper spark plug --- just the length or the wire was wrong
all sorted out,,, i have been driving it... about 500 miles on it now
Thread
Thread Starter
Forum
Replies
Last Post
ncds_fc
New Member RX-7 Technical
1
08-15-15 10:06 AM