Skip to main content
Topic: lost compresion (Read 2444 times) previous topic - next topic

lost compresion

Hey guys. I got a new turbo in and everything seemed fine until a couple mid range pulls, at only 7 psi, when the car started missing like crazy. It was barely able to get itself home. Double checked the timing and I do think it was a tooth off. Got all that taken care of, and the timing is fine, distributor is moving. Fired it up and it was better but still ran like . Removed the intercooler and started pulling plugs. Plugs looked good so I got out the ole compresion tester and found no compresion in 1 and two and found 115 in three, 125 in four. Has a new head gasket with just a couple hundred miles on it, could it have blown? No water in oil and oil in water and no smoke.

 

lost compresion

Reply #1
Did you pop the oil filler cap off while it was running to see if there was a lot of blowby? You may have blown the rings.
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

lost compresion

Reply #2
No I havent, These things always have a little dont they? How much would be too much? And would ring go catastrophicaly like that? usually rings wear dont they? I was only at about 3000, maybe 3500 when it went to $%!t.

lost compresion

Reply #3
Depends on what condition the motor is in. Lots of miles, age, wear, and sock a bunch of boost on it

I knew this guy in college with a 62? Impala. Had a 283 in it with about a billion miles on it. He had a top end job done to it. And when it fired for the first time the blow by was SO bad (how bad was it) it was SO bad it blew the oil breather cap off the filler tube on the front of the intake, and made a thump as it hit the underside of the hood.:punchballs:
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

lost compresion

Reply #4
I vote for head gasket...

I've only seen one engine with the piston ring lands blown out on adjacent cylinders, and that was a 428 Cobra Jet...

lost compresion

Reply #5
Quote from: TurboCoupe50;246541
I vote for head gasket...

I've only seen one engine with the piston ring lands blown out on adjacent cylinders, and that was a 428 Cobra Jet...


x2


OOOH!!!  I'm a Eco Hypermiler :burnout: Not bad for 79mph on the interstate 2hours a day

lost compresion

Reply #6
Ah . stupid cheap gasket. I guess I will pull the head tomorrow. dang it.

lost compresion

Reply #7
x3
92 T-Bird 5.0HO(yeah I know it is over an 88 but I like this forum :D )
Upgraded exhaust 2.5" to3" to 2.5" duals and single 3" hi-flow cat, deleted smog and a/c, cold air,ported mass air(for now).
upgrades to come-T-5 swap,3.73gears,Gt40p intake&heads,cam.

lost compresion

Reply #8
use a copper gasket and you wont have this problem any more:D

although its possible,, i cant see having

"""ZERO"""" psi on 1 and 2.  Sure thier strokes are 180 out but it would seem that needs to be one hellava break in both head gasket rings in order for one cylinder to bleed into the other in order not to have a psi reading on your guage.

With a blown headgasket, you should have some sort of reading.

if this were a v motor, i would verify a headgasket by removing the rockers on the two cylinders.  Now both cylinders valves are closed.

Next I would stuff one cylinder spark plug hole with tissue paper real tight.

next i would insert air presure into the other cylinder.  If the tissue paper blows out , its probably a headgasket leak in between cylinders.  This does not rule out a crack in the head but that crack would have to be lower than the valve seats and more along the bottom of the head in between valve chambers.

its really odd the gasket is blown this early and if it is, you need to look at what you did not do correctly the first time.

lost compresion

Reply #9
Quote from: Superdavesds;246576
Ah . stupid cheap gasket. I guess I will pull the head tomorrow. dang it.


is there such a thing?  what do you mean?  most of them are constructed the same.

lost compresion

Reply #10
Quote from: jcassity;246581


although its possible,, i cant see having

"""ZERO"""" psi on 1 and 2.  Sure thier strokes are 180 out but it would seem that needs to be one hellava break in both head gasket rings in order for one cylinder to bleed into the other in order not to have a psi reading on your guage.

With a blown headgasket, you should have some sort of reading.

i

I've done it twice. No reading on adjacent cylinders. All of catjam witnessed that this past year.
 
Headgasket for sure. I've blown them between 2 and 3, and between 3 and 4.

Also, don't waste your time with a 1035 gasket, they are not specific to our application, the 8993 gasket works well.
It's Gumby's fault.

lost compresion

Reply #11
my 86 turbo had the gasket blown from 2 to 3 and the way i found out was when i did the compression test.
 i had all 4 spark plugs out and when i had the gauge in #2 the air was coming out of 3 spark plug hole, same would happen when i did #3. nether 2 or3 had any reading on the gauge . when i pulled the head. there was about 1 inch of the gasket gone and the was a groove in the block surface! so that why i now have the 86 mustangSVO engine in for replacement.
remember it easier to fix them, than to find them after they been crushed.

V6 = juvenile delinquency!

lost compresion

Reply #12
update?
5 Mopars, an S-197, and the Turbo Twinkie[SIGPIC][/SIGPIC]

lost compresion

Reply #13
Quote from: Tbird232ci;246742
I've done it twice. No reading on adjacent cylinders. All of catjam witnessed that this past year.
 
Headgasket for sure. I've blown them between 2 and 3, and between 3 and 4.

Also, don't waste your time with a 1035 gasket, they are not specific to our application, the 8993 gasket works well.


I was always under the impression that the 1035 was the way to go on the 2.3T. What exactly makes the 1035 different than the 8993? I'm just wondering since I have a 2.3T sitting in the garage waiting to go in the Ranger.
85 Tbird 5.0
78 F150 351w
13 F150 4x4 3.5 Ecoboost

lost compresion

Reply #14
Sorry for the delay guys. Out of town on a family emergency. Have not had a chance to look at the car yet. I was refering to the "Stupid cheap gasket" as the felpro gasket that came with the "head gasket set" from AutoZone. I could not even tell you what the number on it was. But I can tell you that I have built a few motors in my day , and have cerainly gotten myself into a posistion to be compitent at changing a head gasket. I have done a few 2.3s in my day, first one was truely a pinto, and two ford rangers. However this is my first turbo motor of its kind and I think the "cheap gasket" may not be up to par. I have read a lot about the graphite gaskets. Any one care to weigh in on this? And which Copper oring gasket is it you were mentioning before?