How Bad Are My Rings?

[nissan_star]

I recently did a compression test, the right way i might add, and found compression to be 145 145 150 150. Even though it was 36 deg. outside, that seemed low compared to my 160 160 160 160 when it was 75 deg. outside. My engine feels very healthy and only has 119k miles on it, but my compression tester might be older than I am, for real. I decided to test again anyway but this time i dropped about a capfull of oil in through the spark hole and got 160 160 161 160.

Are these rings safe to put boost on?Can compression testers go bad?

[dblanehopr]

anything can go bad, but you'd be smart to wait til that oil burns off... then do the test again....

then do it again...

then you'll know if it's the tester or the rings.

[nissan_star]

How long does it take for the oil to burn off? Did the temp outside matter?

[dblanehopr]

no, the temperature outside doesn't matter.

the oil'll burn off after you drive it around a bit.

you were basically doing a leak down test... right.....

the oil sealed the rings, gave it better compression...means you got some loose rings.

do it again, and it'll tell you if the tester is good.

[eazye2000]

Your motor is fine. It's in very good shape.

When you got 160 across the board, that is very good.

When you got 160 again across the board, with the oil, that's even better.

Typically, when you add oil after the initial test, and you get better compression, that means your rings are leaky. In your case, there was little or no change, which is awesome.Not sure if I said that right. Hope you catch my drift.

Temp outside doesn't matter. I think you want to do it with the motor just warm anyways. I don't recall.Oil will burn off after about the first minute or less of running.

Hope this helps.

[nissan_star]

I think you misunderstand my situation. The first time I tested the compression, in like may, it was about 160psi all across +-2psi. I have since switched to synthetic oil and wanted to see if there was a difference, so i tested again on Dec 20. The numbers i have now were around 145 and 150, no higher, until i put a capful of oil in through the plug then they were all 160 or 161.

Do you think switching to synthetic caused the car to lower compression?

[480sx]

Its plausible that switching caused this. Switching to a synthetic oil cleans EVERYTHING out of your motor. It could have scraped all the crap that was on your cylinder walls keeping your rings seated well off in doing so.

How many miles were on your motor when you did the switch?

You were doing the test on a fully warmed motor, with the throttle plate wide open correct?

[nissan_star]

How many miles were on your motor when you did the switch?

118k exactly, almost 100% positive previous owner didnt use synthetic

You were doing the test on a fully warmed motor, with the throttle plate wide open correct?

motor was ran for 15-20 mins, temp gauge was as high as it ever gets when i drive it.

Whats the throtle plate again? I did it the same way i did it in May to get my original 160psi readings

[dblanehopr]

try switching back to a 10weight and see what happens.

[480sx]

Hmm 118 isnt that many miles. Idk about your issue honestly, but i mean if thats all you changed in the last 6 months its possible that the syn did do that. I would worry about it, just drive it.

Your supposed to test the compression while holding the gas pedal(thus opening the throttle plate) all the way down.

[dblanehopr]

na, don't worry about it bro... just let your rings slide til you burn up a bearing......... and let your car miserably sit in your driveway until you can fix it a year later, like me.

[480sx]

His rings are 5 psi below the stock limit at worst. Hes saying his car is driving great. He doesnt even know if his compression tester is reading accurately or not(those things do go bad over time). What are you suggesting? Ripping apart a 100k mile motor because of some compression test results?

Your going to spin a bearing because your rings are 5 below FSM spec? CHECK YOUR OIL.

OP - I seriously would invest in a new comp tester and try it again with the throttle plate open and the engine fully warmed.

[dblanehopr]

he went from 160 to 145 in half a year.

of course the car's still driving great....you can't tell it's bad until it blows.

but whatever man.. just for kicks, what exactly do you think would be a good time to replace rings that are starting to give? when he's burning a quart of oil a day?

[nissan_star]

I figured you meant push the throtle, I crank it like 7 times too, is that too much?

I have Castrol Syntech 10W 30 in right now.

[dblanehopr]

i used castrol too, but i've always had high mileage, so i use the high mileage.

7k you mean? like 7k rpms?

[nissan_star]

like i turn the engine over like 7 cranks, as it says to do on the box of my grandpas compression tester.

[dblanehopr]

meh... i just crank it until i get the max psi it'll read. usually a few revs gives it too ya.

but that guy's right about doing it while the engine is warm.

it's nice to know what psi your reading at cold levels too though... cuz cold starts on engines is a harsh thing.

just be glad you're able to do it while running... every compresion test i've done was to try to find why a car wasn't starting. lol

[nissan_star]

I guess I will get my own compression checker at sears and try everything again somtime soon. The only problem is I am out of synthetic oil, so if were to put some in through the plugs, I would be putting in normal. Is this a problem if I only do it a couple of times?

[dblanehopr]

na, couple times shouldn't hurt nothin.

it just burns off. it's when your chamber is gettin constant oil that you have to worry, cuz you'll burn up your oil before you know it and melt a bearing.

i'd test both cold and hot to see if there's a difference.

[eazye2000]

I think you misunderstand my situation. The first time I tested the compression, in like may, it was about 160psi all across +-2psi. I have since switched to synthetic oil and wanted to see if there was a difference, so i tested again on Dec 20. The numbers i have now were around 145 and 150, no higher, until i put a capful of oil in through the plug then they were all 160 or 161.

Do you think switching to synthetic caused the car to lower compression?

Sorry I misunderstood. Must have been sensory overload with all the numbers.

[dblanehopr]

I guess I will get my own compression checker at sears and try everything again somtime soon. The only problem is I am out of synthetic oil, so if were to put some in through the plugs, I would be putting in normal. Is this a problem if I only do it a couple of times?

autozone or orielly's'll have a cheaper one. i haven't had a prob with mine and mine was in storage for a year. craftsman is only medium grade.... if you want quality get a Harbor Frieght or SnapOn

[480sx]

For a compression test just crank the engine for a full two seconds and stop. Have the engine fully warm and the throttle plate all the way open. This is the correct way to check compression.

craftsman is only medium grade.... if you want quality get a Harbor Frieght or SnapOn

LOL

Craftsmen are fine. Snapon/Mac are probably the better ones your going to buy. Harbor freight is good for some things. Except torque wrenches and compression testers(among many other things).

DBL, some of the things you say are really.... Stop talking out of your a$$.

[dblanehopr]

i work in a fkn muscle car shop. in other words.. i work with steel and iron parts that don't break when you apply pressure.. but i've broken more craftsmen wrenches than anything.

so how bout you try not actin like every other ahole on the net and try to have a conversation without insulting someone.

snapon and husky never break on me.

and harbor freight is good because of the price. that's why i said that.

try asking before insulting for once. it'd be nice to actually finish a fkn thread on this site wi/o someone being a prick.

[480sx]

Didnt really even insult you guy, just telling you like it is. A lot of what your saying is bs or simply wrong. You can try to spin the harbor freight thing all you want..

Again, snapon and HUSKY?! Husky tools are wayy worse than craftsmen.

Were not having a conversation here, were in technical thread in a technical forum. Your posting information that is wrong at best.

so how bout you try not actin like every other ahole on the net and try to have a conversation without insulting someone.

try asking before insulting for once. it'd be nice to actually finish a fkn thread on this site wi/o someone being a prick.

I dont think you notice whos being an ******* here. Self awareness bud.

In addition, your problems that your having here on nico are because of the way you post. You post like your a guru or know a lot when your consistently spreading bad information, or making questionable remarks. This is the main reason you keep getting flamed, added to that is the fact that your not aware of the tone of your posts.

I have taken the time to explain this to you. Ka-T subforum is a tech forum, and if you keep posting BS im going to keep correcting you. This is not the place for a personal grievance. If you have a problem with me, you can take it up with a moderator. Do not use this forum to try to start a pissing and moaning match with me.

[dblanehopr]

i'm not trying to post bad information. all i've said here is 160psi to 145psi when he dropped oil in the chamber, if the tester was good,

~Typically, when you add oil after the initial test, and you get better compression, that means your rings are leaky. In your case, there was little or no change, which is awesome.~Temp outside doesn't matter. I think you want to do it with the motor just warm anyways. I don't recall.Oil will burn off after about the first minute or less of running.

~no, the temperature outside doesn't matter.~the oil'll burn off after you drive it around a bit.~you were basically doing a leak down test... right.....~the oil sealed the rings, gave it better compression...means you got some loose rings.

do it again, and it'll tell you if the tester is good. cuz if you do more than one test and get the same numbers, the tester is good.

i'm not sure what why we're arguing about me givin bad info.

I think you misunderstand my situation. The first time I tested the compression, in like may, it was about 160psi all across +-2psi. I have since switched to synthetic oil and wanted to see if there was a difference, so i tested again on Dec 20. The numbers i have now were around 145 and 150, no higher, until i put a capful of oil in through the plug then they were all 160 or 161.

~motor was ran for 15-20 mins, temp gauge was as high as it ever gets when i drive it.~Whats the throtle plate again? I did it the same way i did it in May to get my original 160psi readings

~he went from 160 to 145 in half a year.~of course the car's still driving great....you can't tell it's bad until it blows.~but whatever man.. just for kicks, what exactly do you think would be a good time to replace rings that are starting to give? when he's burning a quart of oil a day?

i've gone through two sets of rings given out, both on s13's... justifiably;.. it was straight bull and still ticks me off somedays. losin your 240 cuz of funds hurts. still got this one, tryin to do somethin with it. as for rings going out, just asking, what would worry you? and with him wantin to boost it? just asking?

man, i ain't tryin ta fight. wasn't in the first place. i was just talkin to the man here about his car. workin it out, ya kno. ain't gotta get hostile and flame.

Merry Christmas! ...

Modified by dblanehopr at 12:14 PM 12/25/2008
Modified by dblanehopr at 12:22 PM 12/25/2008

[480sx]

Its all good bud, merry christmas.

[nissan_star]

Im glad to see you guys are done being silly, but on with the thread!

I got a new, never been opened, compression tester and did a new test. This time I made sure that the needle stoped moving before I stoped cranking the engine, which happened to be like 9-11 cranks or 5 seconds, which is more then I did before. My resluts were; 181, 180, 181, 182. This was after several tests of getting the same result. I even added oil through two of the plugs, one changed like 2psi the other changed like 4psi(#1 and #4).

I am very happy right now even though I cant explain it If you have any ideas on why my numbers increased so much please tell, my only guess is that i was stoping the other tester before it was reading full pressure and when I added oil during tests with old tester it was just getting to the actual pressure faster, hence much higher numbers. I am confident in my engine again but i will do more tests later on before I start my T build.

[480sx]

"For a compression test just crank the engine for a full two seconds and stop. Have the engine fully warm and the throttle plate all the way open. This is the correct way to check compression." Per FSM direction. Thats the standard way of checking comp.

Either way, your probably fine your gauge just crapped out on you. That whole thing about switching to synthetic lowering your compression was just wild, i was trying to hypothesize but i really couldnt even buy my own theory. Makes a lot more sense that your gauge was bad.

[dblanehopr]

lol, hell yeah it does.

gd bro.. 180... boost that fkr! lol