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adams86lxi
02-24-2004, 06:35 PM
i just did a compression test on my 86 lx-i! the results were

#1-150psi
#2-120psi
#3-120psi
#4-150psi

is this good? and why does the 2 inner cylinders have less comppresion than the 2 outers? I know the 86,87 had a lower compresion than the 88,89s! THANKS!!! :cool:

Neuspeed87lx
02-24-2004, 06:50 PM
all 4 cylinders should be around the same # .... put a few drops of oil into the spark plug hole in cylinder 2 and 3 and do the compression test again .... if the #'s go up you have a problem with the rings not sealing properly possibly.... if it dosent change then its not the rings ..... you could do a leakdown test in the cylinder .... it could possibly be a head gasket going bad

Neuspeed87lx
02-24-2004, 06:55 PM
oh and make sure when your doing the compression test you take all the plugs out first ...then start your tests.....then make sure you disable spark and fuel .... disable spark even though the plugs are out of the hole.... then block the throtle plate wide open .... then make sure the engine is cranked over the same amount for each clyinder.... i ususally count 6 seconds ....

88turboaccord
02-24-2004, 09:10 PM
you most likely have a leaky head gasket between 2&3. Generally that is where it will go if it does. All I can say is run the car, but be prepared to do a head gasket replacement..

adams86lxi
02-24-2004, 09:18 PM
all 4 cylinders should be around the same # .... put a few drops of oil into the spark plug hole in cylinder 2 and 3 and do the compression test again .... if the #'s go up you have a problem with the rings not sealing properly possibly.... if it dosent change then its not the rings ..... you could do a leakdown test in the cylinder .... it could possibly be a head gasket going bad

alright ill try the oil thing tommrow if it dosent rain to make sure it isnt the rings

adams86lxi
02-24-2004, 09:20 PM
you most likely have a leaky head gasket between 2&3. Generally that is where it will go if it does. All I can say is run the car, but be prepared to do a head gasket replacement..

i checked the manuel and it dosent look good it says the compression should be around 210psi maybe it is the gasket! how long do you expect it to last? and could this be the lagging problem i have between 1000rpms and 3500rpms?

88turboaccord
02-24-2004, 09:27 PM
150psi is okay.. It is hard to say how long the motor will last, it depends on how you drive it. It will probably last you 6months to a year with normal driving... If you overheat the car, it will be pretty much shot..

Neuspeed87lx
02-25-2004, 08:03 PM
just do your oil changes frequently and watch the coolant level ..... you could check the headgasket by first bringing cylinder 2 up to TDC on the compression stroke .... so the valves are closed ... then blow air into the cylinder through the spark plug hole .... but be carefull not to put to much pressure in ..... then put your hand over the spark plug hole in cylinder 3 and if you feel air comming out it is 90% the headgasket ....

adams86lxi
02-25-2004, 09:08 PM
just do your oil changes frequently and watch the coolant level ..... you could check the headgasket by first bringing cylinder 2 up to TDC on the compression stroke .... so the valves are closed ... then blow air into the cylinder through the spark plug hole .... but be carefull not to put to much pressure in ..... then put your hand over the spark plug hole in cylinder 3 and if you feel air comming out it is 90% the headgasket ....

alright cool i check it as soon as it stops raining because i dont have a grage to work on it in. Hopefully it will stop raining soon because its suppose to rain the next few days, and i need to go pull some prelude arms out of the junkyard!

Justin86
02-27-2004, 09:19 AM
Also check your valve gaps. I was running low PSI like 130 and all my valve gaps were to tight so I adjusted them and it help. Now I just need a new head, stupid damn valves not seating.

AZmike
02-27-2004, 11:13 AM
Also check your valve gaps. I was running low PSI like 130 and all my valve gaps were to tight so I adjusted them and it help. Now I just need a new head, stupid damn valves not seating.

I have a spare head. It worked fine when I pulled it. Let me know if you're interested.

Justin86
02-27-2004, 12:34 PM
ok thanks, I was going to check the local pick and pull to see what they had.