slamedturtle

ok. just did a compression and leak down test and the numbers were this starting on the cam side to the distributer side: 170-3%, 170-3%, 170-4%, then 120-46%. i have a G.E. built bottom end with 17,000 miles on the build. also the head is the stock si head with 85,000 miles on it. it is also tuned with hondata. have not had any detonation.

Ok here is the thing i am not burning any oil and not losing coolant. my tuner said it was the exauhst valves were bent on that cylinder. but he also said it might be the rings. with 46% leak down i would be burning **** loads of oil right. has anyone ever had this prob. please help me with some info or what else to do before i go and buy a built head and find out that is not the problem. thanks ht

99B16Si

bent exhaust valve


Modified by 99B16Si at 2:36 AM 4/21/2004

B18C1CYA

well 46% leak down is a lot. are you shure the valves were shut in that cylinder when you checked it. and also did you look in the radiator to see if there where any bubbles? liesten with a tube at the dip stick hole and oil fill you will here the air comming out. if there are no bubbles or cant hear anything from the oil fill or dipstick hole ,listen in the intake and exhaust if it leaks there than its your head or the valves arent shut all the way.

slamedturtle

yeah we listened in all those places. i could hear air coming from the exauhst. when you would stop forcing air into the cylinder the air would stop. but i could hear air coming from the oil dipstick hole in every cylinder. that is what threw me off. i have not pulled the head yet. i was wanting to get some more info before pulling the head and finding out it is the rings. but like i said with that high of a % of leakdown past the rings, there would be oil every where right. the plugs dont even have any sign of burning oil.

slamedturtle

yeah the head is stock. but could it be valve seals. i am tunned with 16 pounds of boost daily driven. but i am very conservitive with the boost. gas is higher than a motha ***** right now. also is there any other way to bend a valve without any detonation. thanks

slamedturtle

i also pulled the valve cover to see if anything looked out of place or broken and everything looked fine from what i could see but that does not tell me much. valves looked like they were all seated fine but with that high of pressure anything is possiable.

slamedturtle

ok just curious here. what are the chances of this happening. and if this is the case would it be best to just go ahead and replace all the rings or just the ones on this piston. and is it going to require more machining. like always money is the question. i built the motor to semi-prevent **** like this but i know it happens. thanks

B18C1CYA

so was the sound in the exhaust only in that cylinder with 46%?

slamedturtle

yes. it was. but like i said i could not tell on any cylinder. i could hear the air from the dipstick hole and oil cap in every cylinder. or i think i could. should you hear anything at all. my tuner seemed positive that it was from the exauhst valves. but what other way can you bend a valve besides detonation. and i know for shure it was not detonation. he tuned it pretty rich and the timing is fine. i really did not ask any questions while we did the tests. and did not start thinking about it till tonight. so i am starting to second guess my tests.

99B16Si

if your running 16psi im guessing u dont have stock internals so the eliminates the bust ringland theory. if your head is stock i wouldnt be surprised to see a bent exhaust valve. either way the head needs to be pulled.

try checking your valve lash clearances on that cylinder. if you have a bent valve at least one will be way off

slamedturtle

thanks man that was actually my next try. yeah i just find it hard to beleive that the rings are already bad. i dont boost alot and i dont run the car hard. by the way dont know for shure but the whole reason the bottom end was built was because that cylinder started having low compression readings. i am just curious if it was a valve then. even after the build that cylinder had lower compression readings than the other 3. but this was the first time to do a leak down test. you know something crazy though. i still killed a vette on the highway with 3 1/2 cylinders thanks for your reply