Compression Test Results

Pages:
1
2

Compression Test Results
Topic Started: May 31 2010, 07:29 PM (321 Views)
Michael	May 31 2010, 11:22 PM Post #16
Posts: 420 Group: Members Member #81 Joined: May 11, 2009	compression tests work like this, all cylinders must be with in 10 percent of each other. 10 percent of 155 be 15.5 points. which would mean a base would be 139.5 minimum.... It seems to me head gasket, idk much about the ka motors, but if two cylinders side by side have a low compression result, than thats head gasket. why would rings go bad in two cylinders but not 4? the other two have great compression, the others dont. look in your oil. is it milky(antifreeze in oil), exhaust smell sweet? (burning antifreeze) check it out.



Deleted User	May 31 2010, 11:23 PM Post #17
Deleted User	Michael May 31 2010, 11:22 PM compression tests work like this, all cylinders must be with in 10 percent of each other. 10 percent of 155 be 15.5 points. which would mean a base would be 139.5 minimum.... It seems to me head gasket, idk much about the ka motors, but if two cylinders side by side have a low compression result, than thats head gasket. why would rings go bad in two cylinders but not 4? the other two have great compression, the others dont. look in your oil. is it milky(antifreeze in oil), exhaust smell sweet? (burning antifreeze) check it out. this. 10% is a big margin though, 15 point difference is excessive. thats why i said 3.
Deleted User


Michael	May 31 2010, 11:38 PM Post #18
Posts: 420 Group: Members Member #81 Joined: May 11, 2009	but Ive always been tought that some were 10-15 points is okay. But his is way off with the 20 points, im almost sure of head gasket failure. Two cylinders side by side with low compression but the others are okay just says that two me. My numbers and again is a totally different set up is my 10:1 355 are all around 155-165 and that in my opinion is normal.



Deleted User	May 31 2010, 11:41 PM Post #19
Deleted User	Michael May 31 2010, 11:38 PM but Ive always been tought that some were 10-15 points is okay. But his is way off with the 20 points, im almost sure of head gasket failure. Two cylinders side by side with low compression but the others are okay just says that two me. My numbers and again is a totally different set up is my 10:1 355 are all around 155-165 and that in my opinion is normal. yea id say its probably a headgasket as well, definitely the logical thing. but as far as the points go, i personally wouldnt run a 10-15 point difference in my engine, but thats just me. as far as it being ok, sure the engine may run decent, but there will be a definite power loss. ive just been taught that 3 point difference is normal 5 is average and anything over that is starting to push it. but like i said thats just me.
Deleted User


Michael	May 31 2010, 11:44 PM Post #20
Posts: 420 Group: Members Member #81 Joined: May 11, 2009	yea thats probably just different motors and stuff too, I mean we both work on different things, but no matter what the problem is it means the same thing! haha.



Deleted User	May 31 2010, 11:49 PM Post #21
Deleted User	Michael May 31 2010, 11:44 PM yea thats probably just different motors and stuff too, I mean we both work on different things, but no matter what the problem is it means the same thing! haha. very true!
Deleted User


illmatic	Jun 1 2010, 08:25 AM Post #22
CunningLynguist Posts: 515 Group: Members Member #91 Joined: May 31, 2009 My Ride: '90 S13 hatch	the thing is cylinder 4 also had a bad compression rating..i didnt have any difficulty trying to screw the the gauge in..so even if 3 had the problem with the threads n what not, 4 should be just fine, correct? i mean cyl's 1 and 2 were good...and 2s right next to 3



Michael	Jun 1 2010, 09:25 PM Post #23
Posts: 420 Group: Members Member #81 Joined: May 11, 2009	yea thats what I was saying though, if you can get the checker in and get a reading and both cyl 3 and 4 have the same low compressoin than that kinda points to a bad headgaskte, just check the oil and for all the signs of a bad gasket. The engine will still run fine just down on performance and such.



illmatic	Jun 2 2010, 02:57 AM Post #24
CunningLynguist Posts: 515 Group: Members Member #91 Joined: May 31, 2009 My Ride: '90 S13 hatch	It could be that, I did an oil change last week and didn't notice anything out of the ordinary.



1 user reading this topic (1 Guest and 0 Anonymous)


« Previous Topic · KA · Next Topic »

Pages:
1
2