Engine Bad Blow By.

[ShyBoyCA6]

"The big bad with the car as I see it is that it has really bad blow by, on a compression test it was, 64, 59, 160, & 49. If it weren't for this I'd be keeping it as a nice commuter to be built upon later, I just don't have the desire to pull the engine right now."

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Ok i dont understand the meaning of these numbers in a compression test but heres what i've been told how it got these number. Unless Harrison see this to correct me.

Ok a younger guy owned the car before him and told him that the car overheated. dont know if he drove it till it died or what. I would like to know meaning like blown head gasket or piston rings are shot? the gasket was badly beaten when i replaced it i took pics of everything including the pistons. which looked ok and passed inspection and some members. Members on here told me to replace the head gasket, seafoam, and radiator flush the car. please note that i haven't seafoamed or flush the system yet due to lack of funds.i know im gonna need a new PVC since it was smoking as soon at the motor warmed up. Is there something that im missing on what to do? please any info or tips to getting it done before Rhonda also decides to give up on me. i should be able to do the 5spd swap early Jan. and start driving the car.

Thanks for any InFo

[2oodoor]

those are sort of unusual readings, typically there are one or two low readings if it were a HG.
That looks more like poorly seating valves to me, or out of time or rockers way out of adjustment.

I say typically so that doesn't mean all the time.

[ShyBoyCA6]

thanks roo doo ill look into that :)

[g.frost]

Strictly speaking 'blow by' is bad rings, but bad compression numbers can be caused by other things like valves or bad head gasket. If you are getting lots of blow by after replacing the head gasket,,,, most likely suspect is the rings. ....how many miles on the engine? May be that you can clean up the ring pack with solvent or some such treatment, ....maybe.

Old shade tree method of checking the valves (with the head off) is to fill em with gas and see if it leaks out through the valves.

[ShyBoyCA6]

Engine has 102k miles on it still young. ill look into new valves and piston rings

[g.frost]

Sad, these engines will do 3-400K without ever being opened if well maintained and not abused. I'm at 156k, never opened(just valve adjust), no oil burning, no blow by, and runs good as new.

[ShyBoyCA6]

i know what you mean. sadly i bought the car like that and ask what was wrong with it. i dont wanna sell it since i already put money in it. so im gonna fix it.

[obdriver6]

Does are some weird numbers. If it was overheated really bad then I would have to say its the rings, try and add a little bit of oil in each cylinder and see if the compression goes up. if there is no change then I would say its the valves or BHG. Check if the valves are adjusted right.

[ShyBoyCA6]

Gonna have to look at the valves as soon as I get it running again and hopefully doesn't smoke. I recently broke one of the header studs off and would have to get that fixed first. I'm doing a wire tuck on the car mean while since I'm going obd1 and wanna get the wiring done in the car. Ill post pics of this project tomorrow on another thread since a member ask me how it was coming along. The wire tuck is not gonna be like elpuma's bay but at least you will notice something.

[elpuma]

just let me know and i can help you bro. shit i'll even go to a junkyard and video you a how to lol. i'm a bit drunk but yea lol

[ShyBoyCA6]

lol its all good elpuma. oh im doing all of this while relocating my fuse box inside the car with AC still intact :).

[elpuma]

oh shit! jajaj cant wait to see where you gonna mount it. maybe under that passenger seat??

[ShyBoyCA6]

oh shit! jajaj cant wait to see where you gonna mount it. maybe under that passenger seat??

Maybe haha we'll see.

[2oodoor]

My 306,000 mile A20A1 that I had in the LX before the swap smoked like a bitch right after I replaced the HG and fresh valve job. It stopped smoking after it ran a bit.
I beat on without mercy and it never used a drop of oil. I did have a small oil leak up on the front right but after retorquing the head after a warm up cycle that stopped as well.
Unlike D series engines, these can stand a fresh head job without blowing the rings.
To make it easy I set the valve lash at 007 and 011, being very carefull to put plenty of light on the subject to ensure I was holding the feeler guage level to the gap.
I set the T belt at flywheel mark, a faint scribed "T" on it there rather than any of the other markings. This put the crank keyway at 12 clock perfect 0 TDC.
Doing a compression check, disable the fuel injection as well as the coil wire. Just in case by some fluke the injectors are wetting down the cyl. which will give you a bad reading.
Remove all the plugs to do it. If you get low readings on a cyl, go back again and do them with a squirt of motor oil in the plug hole first.

I almost would say with these particular engines you stand to do more damage to the rod bearings running it with a blown HG than you would rings.

Then again Ive been known to speak from instinct rather than facts at times.

[ShyBoyCA6]

i will check it again but that will take me some time to do since its in pieces right now haha. but if it fails, motor will come out and ill swap in (can't believe im gonna say this)a B Series Motor in it. (OBD1 B16)

[Dr_Snooz]

If it blows smoke constantly and more smoke under load, then I would say it's rings.

[ShyBoyCA6]

Thanks for the input Dr Snooz

And "wire tuck" is 75% percent done ill post picks later tonight. Not much of a difference haha.

http://s1180.photobucket.com/albums/x410/xenogears_32/