rotary compression tester
03-02-08, 06:39 PM
#27
Maybe you're misunderstanding or listening to the wrong people. There really aren't any discrepancies about how to comrpession test a motor. It's pretty straight forward and so are the numbers you should be getting.
Testers shouldn't be too off from one another if they're a decent brand name that hasn't been abused.
Hose length makes no difference unless the hose swells, which it shouldn't if it's in GC.
Why shouldn't the tester be able to tell you all of those things? 120 psi is 120 psi. I don't care how much the sensor costs, it means the same thing.
If a motor is excellent, it will read 110+ with the valve closed. Then, with the valve open it will give even sweeps at a lower pressure, indicating that all of the faces were giving that 110 psi value. If the sweeps are uneven with the valve open, one or more faces would be making less than 110 psi.
You can just hold that schrader valve in with your finger. I see no reason to remove it permanently.
Testers shouldn't be too off from one another if they're a decent brand name that hasn't been abused.
Thank you for your insight on that Ted. I suspect that the LENGTH of the hose makes a difference as well. I am sure that I will get a different PSI max with an 18" hose vs. a gauge threaded directly into the spark plug hole.
With the 'bounce' part of the test, the damping of the individual gauge will make an enormous difference in the psi of the bounce-what is important here is that the bounces are relatively uniform, not what PSI the bounces attain.
This testing can accurately identify the following:
1.) Blown apex seals/side seals.
2.) Compression uniformity between rotor faces.
3.) Relative compression between front and rear rotors,
4.) Extremely low overall compression, ie. a worn out motor.
What it cannot do is the following:
1.) Tell you if the motor is fragile, i.e. 'about to pop'.
2.) Tell if an engine is in really excellent condition.
3.) Tell you relatively fine differences between the faces on a rotor.
And we didn't even go into the cranking speed calibration.
With the 'bounce' part of the test, the damping of the individual gauge will make an enormous difference in the psi of the bounce-what is important here is that the bounces are relatively uniform, not what PSI the bounces attain.
This testing can accurately identify the following:
1.) Blown apex seals/side seals.
2.) Compression uniformity between rotor faces.
3.) Relative compression between front and rear rotors,
4.) Extremely low overall compression, ie. a worn out motor.
What it cannot do is the following:
1.) Tell you if the motor is fragile, i.e. 'about to pop'.
2.) Tell if an engine is in really excellent condition.
3.) Tell you relatively fine differences between the faces on a rotor.
And we didn't even go into the cranking speed calibration.
Why shouldn't the tester be able to tell you all of those things? 120 psi is 120 psi. I don't care how much the sensor costs, it means the same thing.
If a motor is excellent, it will read 110+ with the valve closed. Then, with the valve open it will give even sweeps at a lower pressure, indicating that all of the faces were giving that 110 psi value. If the sweeps are uneven with the valve open, one or more faces would be making less than 110 psi.
You can just hold that schrader valve in with your finger. I see no reason to remove it permanently.
03-03-08, 07:40 AM
#28
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If you have a compression tester with a check valve in the end of the hose and another one on the side of the gauge, you'd remove the one in the end of the hose.
If you remove or just depress the valve on the side of the gauge, the pressure is going to be lost out the side of the gauge. In other words the gauge itself isn't going to see the complete pressure if you remove the one on the side of the gauge.
If you remove or just depress the valve on the side of the gauge, the pressure is going to be lost out the side of the gauge. In other words the gauge itself isn't going to see the complete pressure if you remove the one on the side of the gauge.
03-03-08, 10:06 AM
#29
Lives on the Forum
Hose length does make a difference.
The pressure has to travel the whole length of the hose.
Remember, the gauge is a dead-end.
Longer the hose...slower the reaction to the gauge.
I guess it depends on how sensitive the gauge is...
Given identical gauges...change the hose length will change the way the gauge reacts.
-Ted
The pressure has to travel the whole length of the hose.
Remember, the gauge is a dead-end.
Longer the hose...slower the reaction to the gauge.
I guess it depends on how sensitive the gauge is...
Given identical gauges...change the hose length will change the way the gauge reacts.
-Ted
03-03-08, 10:21 AM
#30
Hose length does, in fact, make a difference as Ted says. I have conducted many experiments with different length hoses and fittings and I can assure you that the smaller the internal volume of a tester hose/fitting that is pressurized during engine cranking, the more accurate the readings. I believe the difference has to do with the relatively-short duration of the compression pulse not allowing a full pressurization of the larger internal volumes. Which is why I replaced the hose in our early systems with a short screw-in fitting.
03-03-08, 10:50 AM
#31
Would anyone dispute that these guys-Banzai Racing, Keven Landers (RR), Aaroncake, REted are respected experts in the Rotary scene?
Kevin Landers says "8)observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range."
Aaron Cake says "You are not looking for excellent numbers, just three even bounces above 70 PSI."
REted says "By defeating the check valve, we can monitor the three faces of each rotor easily. The key to this "modified" compression test is to shoot for three, even bounces on the compression tester gauge needle. Uneven bounces would indicate a bad seal. Readings between front and rear rotors should be pretty close; the Mazda tolerance is around 20psi between front and rear rotors. "Good" engines should be able to hit around the 100psi mark. Anything lower than 70psi is indicative of a tired engine that needs a rebuild."
Banzai Racing states
3 even bounces of 85 PSI or above is GOOD. Readings above 110 PSI is GREAT!
3 even bounces of less than 85 PSI: indicates that motor is tired, and indicates engine should be rebuilt before causing damage to rotors or rotor housings.
These are the experts. Why the differences? I am NOT criticizing any of these guys-I trust their word and work completely. They each have a methodology that serves the purpose for their own operations. The trouble comes when you test your engine and I want to buy your car. Now your gold plated great compression wonderful rotary engine is, in my opinion a piece of **** 'ready to pop'.
You do know there are two schrader valves in your 'decent brand name non abused' tester, don't you?
03-03-08, 11:19 AM
#32
I've had three different compression testers, bought from Sears (I think), Autozone, and O'reilly's. All 3 of them had a check valve only on the side of the gauge. You hold it down and you get individual sweeps, you leave it open for the overall PSI. I, myself, was unaware the they ever had 2 check valves until today.
03-03-08, 12:11 PM
#33
I've had three different compression testers, bought from Sears (I think), Autozone, and O'reilly's. All 3 of them had a check valve only on the side of the gauge. You hold it down and you get individual sweeps, you leave it open for the overall PSI. I, myself, was unaware the they ever had 2 check valves until today.
Sorry for the cellphone pic.
Ain't it great, this community we have? I learn something nearly every time I log in.
Last edited by jackhild59; 03-03-08 at 12:36 PM.
03-03-08, 12:34 PM
#34
Hose length does, in fact, make a difference as Ted says. I have conducted many experiments with different length hoses and fittings and I can assure you that the smaller the internal volume of a tester hose/fitting that is pressurized during engine cranking, the more accurate the readings. I believe the difference has to do with the relatively-short duration of the compression pulse not allowing a full pressurization of the larger internal volumes. Which is why I replaced the hose in our early systems with a short screw-in fitting.
Nice work.
03-03-08, 01:23 PM
#36
That $100 is money well spent when you are talking to a 'buyer' who proceeds to say, "Mid 90's psi? Damn! It's about to pop an apex seal!"
I am fine using my piston gauge to check my own cars for my own purposes; it tells me what I need to know.
03-03-08, 04:43 PM
#38
Thanks for the compliment,
Larry
03-03-08, 07:06 PM
#39
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Suzuki used to have a rotary compression tester for their rotary bike. Here's some pictures of it. It used a roll of paper and a moving needle. EGK test for rotary motor bikes.
Threw in a jpg of a DI-148U for kicks.
And two jpg of Jack's mechanical tester. No phone involved. Just a scanner.
Threw in a jpg of a DI-148U for kicks.
And two jpg of Jack's mechanical tester. No phone involved. Just a scanner.
Last edited by HAILERS; 03-03-08 at 07:15 PM.
03-03-08, 10:37 PM
#40
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[QUOTE=jackhild59;7934037]For someone with 2000+ posts, you don't really pay much attention to the community at large, do you? With all due respect, there is NO agreement among even the most respected builders on this forum.
Would anyone dispute that these guys-Banzai Racing, Keven Landers (RR), Aaroncake, REted are respected experts in the Rotary scene?
Kevin Landers says "8)observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range."
Aaron Cake says "You are not looking for excellent numbers, just three even bounces above 70 PSI."
REted says "By defeating the check valve, we can monitor the three faces of each rotor easily. The key to this "modified" compression test is to shoot for three, even bounces on the compression tester gauge needle. Uneven bounces would indicate a bad seal. Readings between front and rear rotors should be pretty close; the Mazda tolerance is around 20psi between front and rear rotors. "Good" engines should be able to hit around the 100psi mark. Anything lower than 70psi is indicative of a tired engine that needs a rebuild."
Banzai Racing states
3 even bounces of 85 PSI or above is GOOD. Readings above 110 PSI is GREAT!
3 even bounces of less than 85 PSI: indicates that motor is tired, and indicates engine should be rebuilt before causing damage to rotors or rotor housings.
QUOTE]
Rotary Resurection states
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.
http://www.rotaryresurrection.com/1s...ion_check.html
BTW, I just did my test yesterday and this is exactly what I did and I got three pulses at 30 psi. Accounting for my significant elevation above sea level and the numbers come out right.
This process of compression testing with a regular tester needs to be clarified IMO.
Would anyone dispute that these guys-Banzai Racing, Keven Landers (RR), Aaroncake, REted are respected experts in the Rotary scene?
Kevin Landers says "8)observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range."
Aaron Cake says "You are not looking for excellent numbers, just three even bounces above 70 PSI."
REted says "By defeating the check valve, we can monitor the three faces of each rotor easily. The key to this "modified" compression test is to shoot for three, even bounces on the compression tester gauge needle. Uneven bounces would indicate a bad seal. Readings between front and rear rotors should be pretty close; the Mazda tolerance is around 20psi between front and rear rotors. "Good" engines should be able to hit around the 100psi mark. Anything lower than 70psi is indicative of a tired engine that needs a rebuild."
Banzai Racing states
3 even bounces of 85 PSI or above is GOOD. Readings above 110 PSI is GREAT!
3 even bounces of less than 85 PSI: indicates that motor is tired, and indicates engine should be rebuilt before causing damage to rotors or rotor housings.
QUOTE]
Rotary Resurection states
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.
http://www.rotaryresurrection.com/1s...ion_check.html
BTW, I just did my test yesterday and this is exactly what I did and I got three pulses at 30 psi. Accounting for my significant elevation above sea level and the numbers come out right.
This process of compression testing with a regular tester needs to be clarified IMO.
03-03-08, 10:51 PM
#41
I figure that the pressure release valve on most compression gauges is somewhat large, so while even bounces will tell you something, if you get even bounces at 30psi instead of 80psi it's probably just a result of the design of the gauge.
That's my take on it.
That's my take on it.
03-03-08, 11:08 PM
#42
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03-03-08, 11:25 PM
#43
Seriously dude? Over compression testing? It's really not worth my time, but here goes:
Your realize that you just made an *** out of yourself, right? There's no need to get all shitty with me, especially when you're just parroting information with no experience.
The rotary community at large? What? I'm on this forum and I work on cars for a living. What the hell else do you expect me to do?
You fail at being an asshat to me. Let me count the ways:
1. Kevin Landers says 30 psi because he is talking about holding the pressure release valve in and watching for EVEN SWEEPS.
2. Cake says 70 because that is about the bare minimum you need to run and is the lowest number representative of uncompromised seals.
3. Ted said the exact same thing, just with a little info added about higher compression numbers.
4. Banzai said more or less the same thing, but they have higher standards for low compression. 15 psi isn't that big of a stretch, but even so, I'd bet aaroncake's quote is out of context.
5. Yes, those people have experience with rotaries. I'm well aware of them. There are no appreciable numerical or fundamental differences in their testing procedures. You're confused and have poor reading comprehension.
6. Brand names? Sure. SNAP-ON/BLUE POINT, PENSKE, CRAFTSMAN, etc. But like I said, if it's decent quality, there shouldn't be a large difference in the reading. Not sure why you attacked that statement...
I was confused about which valve was being discussed. I still prefer to leave the check valve in the bottom in, but that doesn't change the numbers you get.
And finally, don't talk to me about physics. You'll just get your feelings hurt. What are you, in your first college physics class and think you know it all now?
When I leave the check valve in the bottom of the hose, the hose stays pressurized. With the valve out, the volume of a standard tester hose is negligible.
If you want to break it down into physics, the compression reading should ideally be (compression ratio)X(atmospheric pressure). For 9.5 rotors that would be approximately 140 psi. Obsiously that isn't going to happen unless you have perfect sealing chambers, but the closer to that number the better.
All of this BS aside, if you want a straight answer as to what numbers are good, READ THE FSM!!!
For someone with 2000+ posts, you don't really pay much attention to the community at large, do you? With all due respect, there is NO agreement among even the most respected builders on this forum.
Would anyone dispute that these guys-Banzai Racing, Keven Landers (RR), Aaroncake, REted are respected experts in the Rotary scene?
Kevin Landers says "8)observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range."
Aaron Cake says "You are not looking for excellent numbers, just three even bounces above 70 PSI."
REted says "By defeating the check valve, we can monitor the three faces of each rotor easily. The key to this "modified" compression test is to shoot for three, even bounces on the compression tester gauge needle. Uneven bounces would indicate a bad seal. Readings between front and rear rotors should be pretty close; the Mazda tolerance is around 20psi between front and rear rotors. "Good" engines should be able to hit around the 100psi mark. Anything lower than 70psi is indicative of a tired engine that needs a rebuild."
Banzai Racing states
3 even bounces of 85 PSI or above is GOOD. Readings above 110 PSI is GREAT!
3 even bounces of less than 85 PSI: indicates that motor is tired, and indicates engine should be rebuilt before causing damage to rotors or rotor housings.
These are the experts. Why the differences? I am NOT criticizing any of these guys-I trust their word and work completely. They each have a methodology that serves the purpose for their own operations. The trouble comes when you test your engine and I want to buy your car. Now your gold plated great compression wonderful rotary engine is, in my opinion a piece of **** 'ready to pop'.
So, you would be happy to provide an approved name brand list? Who gets to decide that yours is quality and mine is not? What if Kevin Lander's tester isn't on that list? You want to tell him?
Of course it will make a difference in the bounce test! Effectively the volume in the hose (directly proportional to the length) is an addition to the volume of the compression chamber. Increase the volume of the chamber, decrease the psi measured. You don't agree? What if I used a 3' hose? How bout a 30' hose? Basic physics.
Uhmm, I'm not even sure there is agreement on which Schrader valve people are referring to at which time.
You do know there are two schrader valves in your 'decent brand name non abused' tester, don't you?
Would anyone dispute that these guys-Banzai Racing, Keven Landers (RR), Aaroncake, REted are respected experts in the Rotary scene?
Kevin Landers says "8)observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range."
Aaron Cake says "You are not looking for excellent numbers, just three even bounces above 70 PSI."
REted says "By defeating the check valve, we can monitor the three faces of each rotor easily. The key to this "modified" compression test is to shoot for three, even bounces on the compression tester gauge needle. Uneven bounces would indicate a bad seal. Readings between front and rear rotors should be pretty close; the Mazda tolerance is around 20psi between front and rear rotors. "Good" engines should be able to hit around the 100psi mark. Anything lower than 70psi is indicative of a tired engine that needs a rebuild."
Banzai Racing states
3 even bounces of 85 PSI or above is GOOD. Readings above 110 PSI is GREAT!
3 even bounces of less than 85 PSI: indicates that motor is tired, and indicates engine should be rebuilt before causing damage to rotors or rotor housings.
These are the experts. Why the differences? I am NOT criticizing any of these guys-I trust their word and work completely. They each have a methodology that serves the purpose for their own operations. The trouble comes when you test your engine and I want to buy your car. Now your gold plated great compression wonderful rotary engine is, in my opinion a piece of **** 'ready to pop'.
So, you would be happy to provide an approved name brand list? Who gets to decide that yours is quality and mine is not? What if Kevin Lander's tester isn't on that list? You want to tell him?
Of course it will make a difference in the bounce test! Effectively the volume in the hose (directly proportional to the length) is an addition to the volume of the compression chamber. Increase the volume of the chamber, decrease the psi measured. You don't agree? What if I used a 3' hose? How bout a 30' hose? Basic physics.
Uhmm, I'm not even sure there is agreement on which Schrader valve people are referring to at which time.
You do know there are two schrader valves in your 'decent brand name non abused' tester, don't you?
The rotary community at large? What? I'm on this forum and I work on cars for a living. What the hell else do you expect me to do?
You fail at being an asshat to me. Let me count the ways:
1. Kevin Landers says 30 psi because he is talking about holding the pressure release valve in and watching for EVEN SWEEPS.
2. Cake says 70 because that is about the bare minimum you need to run and is the lowest number representative of uncompromised seals.
3. Ted said the exact same thing, just with a little info added about higher compression numbers.
4. Banzai said more or less the same thing, but they have higher standards for low compression. 15 psi isn't that big of a stretch, but even so, I'd bet aaroncake's quote is out of context.
5. Yes, those people have experience with rotaries. I'm well aware of them. There are no appreciable numerical or fundamental differences in their testing procedures. You're confused and have poor reading comprehension.
6. Brand names? Sure. SNAP-ON/BLUE POINT, PENSKE, CRAFTSMAN, etc. But like I said, if it's decent quality, there shouldn't be a large difference in the reading. Not sure why you attacked that statement...
I was confused about which valve was being discussed. I still prefer to leave the check valve in the bottom in, but that doesn't change the numbers you get.
And finally, don't talk to me about physics. You'll just get your feelings hurt. What are you, in your first college physics class and think you know it all now?
When I leave the check valve in the bottom of the hose, the hose stays pressurized. With the valve out, the volume of a standard tester hose is negligible.
If you want to break it down into physics, the compression reading should ideally be (compression ratio)X(atmospheric pressure). For 9.5 rotors that would be approximately 140 psi. Obsiously that isn't going to happen unless you have perfect sealing chambers, but the closer to that number the better.
All of this BS aside, if you want a straight answer as to what numbers are good, READ THE FSM!!!
03-04-08, 06:00 AM
#44
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GO48........................Just thought I'd say I do like your product and everyone should buy one.
And poop on one and all who hold the relief valve open on the side of the tester and watch 30psi come and go. It's a sorry *** way to do a job. Leave that valve alone and just remove the bottom valve. What's the problem? Can't observe the coming and going of the pressure at 115-120 psi?
And poop on one and all who hold the relief valve open on the side of the tester and watch 30psi come and go. It's a sorry *** way to do a job. Leave that valve alone and just remove the bottom valve. What's the problem? Can't observe the coming and going of the pressure at 115-120 psi?
03-04-08, 10:09 AM
#45
Help the rest of us out
Seriously dude? Over compression testing? It's really not worth my time, but here goes:
Your realize that you just made an *** out of yourself, right? There's no need to get all shitty with me, especially when you're just parroting information with no experience.
The rotary community at large? What? I'm on this forum and I work on cars for a living. What the hell else do you expect me to do?
You fail at being an asshat to me. Let me count the ways:
1. Kevin Landers says 30 psi because he is talking about holding the pressure release valve in and watching for EVEN SWEEPS.
2. Cake says 70 because that is about the bare minimum you need to run and is the lowest number representative of uncompromised seals.
3. Ted said the exact same thing, just with a little info added about higher compression numbers.
4. Banzai said more or less the same thing, but they have higher standards for low compression. 15 psi isn't that big of a stretch, but even so, I'd bet aaroncake's quote is out of context.
5. Yes, those people have experience with rotaries. I'm well aware of them. There are no appreciable numerical or fundamental differences in their testing procedures. You're confused and have poor reading comprehension.
6. Brand names? Sure. SNAP-ON/BLUE POINT, PENSKE, CRAFTSMAN, etc. But like I said, if it's decent quality, there shouldn't be a large difference in the reading. Not sure why you attacked that statement...
I was confused about which valve was being discussed. I still prefer to leave the check valve in the bottom in, but that doesn't change the numbers you get.
And finally, don't talk to me about physics. You'll just get your feelings hurt. What are you, in your first college physics class and think you know it all now?
When I leave the check valve in the bottom of the hose, the hose stays pressurized. With the valve out, the volume of a standard tester hose is negligible.
If you want to break it down into physics, the compression reading should ideally be (compression ratio)X(atmospheric pressure). For 9.5 rotors that would be approximately 140 psi. Obsiously that isn't going to happen unless you have perfect sealing chambers, but the closer to that number the better.
All of this BS aside, if you want a straight answer as to what numbers are good, READ THE FSM!!!
Your realize that you just made an *** out of yourself, right? There's no need to get all shitty with me, especially when you're just parroting information with no experience.
The rotary community at large? What? I'm on this forum and I work on cars for a living. What the hell else do you expect me to do?
You fail at being an asshat to me. Let me count the ways:
1. Kevin Landers says 30 psi because he is talking about holding the pressure release valve in and watching for EVEN SWEEPS.
2. Cake says 70 because that is about the bare minimum you need to run and is the lowest number representative of uncompromised seals.
3. Ted said the exact same thing, just with a little info added about higher compression numbers.
4. Banzai said more or less the same thing, but they have higher standards for low compression. 15 psi isn't that big of a stretch, but even so, I'd bet aaroncake's quote is out of context.
5. Yes, those people have experience with rotaries. I'm well aware of them. There are no appreciable numerical or fundamental differences in their testing procedures. You're confused and have poor reading comprehension.
6. Brand names? Sure. SNAP-ON/BLUE POINT, PENSKE, CRAFTSMAN, etc. But like I said, if it's decent quality, there shouldn't be a large difference in the reading. Not sure why you attacked that statement...
I was confused about which valve was being discussed. I still prefer to leave the check valve in the bottom in, but that doesn't change the numbers you get.
And finally, don't talk to me about physics. You'll just get your feelings hurt. What are you, in your first college physics class and think you know it all now?
When I leave the check valve in the bottom of the hose, the hose stays pressurized. With the valve out, the volume of a standard tester hose is negligible.
If you want to break it down into physics, the compression reading should ideally be (compression ratio)X(atmospheric pressure). For 9.5 rotors that would be approximately 140 psi. Obsiously that isn't going to happen unless you have perfect sealing chambers, but the closer to that number the better.
All of this BS aside, if you want a straight answer as to what numbers are good, READ THE FSM!!!
My 'attack' was a response to your jab. I was a little incredulous and came over too harsh-for this I apologize.
I also want to thank you for making every one of my points. My main point again is that there is no uniform consensus on the methodology for a compression test with a piston tester. Instead there are lots of similar but different techniques listed with different guidelines for analysis. I stand firm on that statement.
Most of what you wrote supports my statement, except for your physics and your conclusions. You also added lots of words of explanation to the various methods/results listed. The rest of us cannot read minds, and we don't have your experience to reconcile those different methods.
I think it would be a fine thing if you, using your professional mechanics skills and your prowess in typing, would author a *concise* methodology and create a tutorial for the rest of us mortals. This would end any disagreements and would give you your first contribution to the archive.
Whaddaya say, help us out?
03-04-08, 04:40 PM
#46
GO48........................Just thought I'd say I do like your product and everyone should buy one.
And poop on one and all who hold the relief valve open on the side of the tester and watch 30psi come and go. It's a sorry *** way to do a job. Leave that valve alone and just remove the bottom valve. What's the problem? Can't observe the coming and going of the pressure at 115-120 psi?
And poop on one and all who hold the relief valve open on the side of the tester and watch 30psi come and go. It's a sorry *** way to do a job. Leave that valve alone and just remove the bottom valve. What's the problem? Can't observe the coming and going of the pressure at 115-120 psi?
03-04-08, 04:50 PM
#48
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I think compression testing has once again been run into the ground. Time to move on.
I still like GO48's compression tester. Not that pricey.
Buuuuuuut, if someone owns a Zeitronix wideband controller, he can monitor the cranking rpms when doing the compression test. With the lead plug removed from the other rotor, I see 280 rpms while spinning the engine.
03-04-08, 06:56 PM
#50
You know, this isn't productive. We were making some progress here.
My 'attack' was a response to your jab. I was a little incredulous and came over too harsh-for this I apologize.
I also want to thank you for making every one of my points. My main point again is that there is no uniform consensus on the methodology for a compression test with a piston tester. Instead there are lots of similar but different techniques listed with different guidelines for analysis. I stand firm on that statement.
Most of what you wrote supports my statement, except for your physics and your conclusions. You also added lots of words of explanation to the various methods/results listed. The rest of us cannot read minds, and we don't have your experience to reconcile those different methods.
I think it would be a fine thing if you, using your professional mechanics skills and your prowess in typing, would author a *concise* methodology and create a tutorial for the rest of us mortals. This would end any disagreements and would give you your first contribution to the archive.
Whaddaya say, help us out?
My 'attack' was a response to your jab. I was a little incredulous and came over too harsh-for this I apologize.
I also want to thank you for making every one of my points. My main point again is that there is no uniform consensus on the methodology for a compression test with a piston tester. Instead there are lots of similar but different techniques listed with different guidelines for analysis. I stand firm on that statement.
Most of what you wrote supports my statement, except for your physics and your conclusions. You also added lots of words of explanation to the various methods/results listed. The rest of us cannot read minds, and we don't have your experience to reconcile those different methods.
I think it would be a fine thing if you, using your professional mechanics skills and your prowess in typing, would author a *concise* methodology and create a tutorial for the rest of us mortals. This would end any disagreements and would give you your first contribution to the archive.
Whaddaya say, help us out?