Compression Numbers
#1
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Compression Numbers
Just did a compression test. The tech said it's just below the recommended. However, looking at the numbers and seeing other numbers on here, it looks like its very low. Can someone give some insight?
PERFORMED COMPRESSION TEST.
ROTOUR #1 278RPM #1-6.0 #2-5.4 #3-5.5 - KG/CM
ROTOUR #2 286RPM #1-6.0 #2-6.3 #3-6.4 - KG/CM
CORRECTION: COMPRESSION TEST COMPLETE, COMPRESSION IS LOW SHOULD BE UP
AROUND 10.2 KG/CM.
REQUIRES FILLING FUEL TANK AND ADDING IN SEA FOAM TO CLEAN
AFTER 1 TANK OF FUEL AND SEA FOAM DRIVEN THREW VEHICLE.
REQUIRES SECOND COMPRESSION TEST.
PERFORMED COMPRESSION TEST.
ROTOUR #1 278RPM #1-6.0 #2-5.4 #3-5.5 - KG/CM
ROTOUR #2 286RPM #1-6.0 #2-6.3 #3-6.4 - KG/CM
CORRECTION: COMPRESSION TEST COMPLETE, COMPRESSION IS LOW SHOULD BE UP
AROUND 10.2 KG/CM.
REQUIRES FILLING FUEL TANK AND ADDING IN SEA FOAM TO CLEAN
AFTER 1 TANK OF FUEL AND SEA FOAM DRIVEN THREW VEHICLE.
REQUIRES SECOND COMPRESSION TEST.
#3
The Blue Blur
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no amount of snake oil will fix the fact that your compression is low
#4
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Yeah that's what I thought. Looking at that chart, my numbers are way low.
Can't afford a rebuild/new engine. How much can I get for it based on those compression numbers? I figure a new engine will cost around $5-6K. Probably going to try to get 1.5-2K for it. Sad
Can't afford a rebuild/new engine. How much can I get for it based on those compression numbers? I figure a new engine will cost around $5-6K. Probably going to try to get 1.5-2K for it. Sad
#5
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A basic rebuild to keep the car on the road will be about $2500. A proper rebuild to get the compression levels close to where they were new will probably start at $4500 and go up from there.
#6
Smoking turbo yay
#7
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I suppose its worth a shot. Seafoam is cheap so why not. The entire can though? That seems excessive.
its a head scratcher to me. Drove it hone from dealership it was rock solid. Those numbers look bad but I noticed they ran them at different rpm. Also I may call back and find out if they normalized to my location because I don't see it on the readings. My location is 192 metres above sea level.
its a head scratcher to me. Drove it hone from dealership it was rock solid. Those numbers look bad but I noticed they ran them at different rpm. Also I may call back and find out if they normalized to my location because I don't see it on the readings. My location is 192 metres above sea level.
Last edited by icemantbi; 07-19-2017 at 06:36 PM.
#8
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You can put the whole can, but it doesn't matter. The correct procedure is actually ingest it into the intake manifold. Mixing it with fuel is preventative at best, pointless at worst.
Another thing people have done is put a spoon of automatic trans fluid down the spark plug holes, and let sit for a day, turning over regularly. I don't promise it will do anything, those numbers are failing by a lot.
How it drives is irrelevant, at idle rpm and above the compression is higher anywah. What matters is how it starts when hot. If it has trouble, that's kind of a giveaway.
Another thing people have done is put a spoon of automatic trans fluid down the spark plug holes, and let sit for a day, turning over regularly. I don't promise it will do anything, those numbers are failing by a lot.
How it drives is irrelevant, at idle rpm and above the compression is higher anywah. What matters is how it starts when hot. If it has trouble, that's kind of a giveaway.
#9
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It takes about 3 to 3.5 seconds to start while hot, but it does start, every time. I assume this will just get worse and worse. Weird thing was is that it just happened all of a sudden. Never had start issues before, then one day it felt different while starting.
likely going to out her up for sale I can't afford a rebuild/new engine ATM.
likely going to out her up for sale I can't afford a rebuild/new engine ATM.
#10
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Got one more question:
Any idea how long this engine will last with those compression numbers? I figure as long as she starts and runs I can keep driving it. Also, I have never pre-mixed before that is something I will do from now on as well. I know everyone recommends Idemitsu, but I can't find that where I live. Any other good alternatives? And will pre-mixing increase the life of the engine? Thanks again for all the help on here.
Any idea how long this engine will last with those compression numbers? I figure as long as she starts and runs I can keep driving it. Also, I have never pre-mixed before that is something I will do from now on as well. I know everyone recommends Idemitsu, but I can't find that where I live. Any other good alternatives? And will pre-mixing increase the life of the engine? Thanks again for all the help on here.
#11
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No one can say, I have seen engines run that make 90WHP but still run seemingly well. My first reman died from one day to the next, it was running fine and then the next day it hit a wall at 7000RPM and then from that point on would not idle or start hot.
And yes seafoam and all other other carbon removal remedies (aside from a rebuild) are a waste of time.
And yes seafoam and all other other carbon removal remedies (aside from a rebuild) are a waste of time.