So I've had this car for about a year only drove it for like maybe 30 minutes total. Car had a blown head gasket fixed it put it back together, then got low oil pressure. Pulled off old oil pump and oil gallery gaskets. Put new ones on. Put it back together, but accidentally switched camshaft timing Mark's. Pulled off timing cover retimed it. Put it back together NOW the car won't start, and I have low compression.

_______________Rear engine
_______________N/A__55 PSI
________________N/A__30 PSI
________________N/A__55 PSI
.______________ Front engine
HEEEEELP

 

Perhaps either the timing is still wrong or some valves were bent when trying to run it with the incorrect timing.

 

oh poop...well I Hope it's just timing 😭 I really don't want it to be piston rings or bent valves

 

Take it apart again and verify the timing marks, then do a leakdown test on each cylinder while you have it apart. You can use a mechanics stethoscope and listen on the headers manifold and hear the airflow if you bent them bad enough, you will FEEL the air coming out of the intake plenum collector if it's an intake valve.

Unfortunately you probably bent the valves, all it takes is the SLIGHTEST contact and they're done for. In the future, you always rotate the engine a few times by HAND (spark plugs removed so you aren't fighting compression) after you reassemble the timing components. The strength of the starter motor turning the engine will EASILY bend the valves.

Remove the heads and have them bench tested if they're leaking.

 

Ahhuh dang well I'll have to look at it on another day car is located at a family members house and girlfriend won't let me go 🙄 will update

 

Left bank

Left bank

Left bank

 

Gotta do a leakdown test to determine where the air is going, compression just tells you that you have the leak. Leakdown lets you diagnose WHAT is leaking.

All 3 of your compression tests on that bank are DRASTICALLY low, you should see a minimum of about 115-120psi for a REALLY worn out motor (250k hard miles). Normal high compression psi will be 185-200+

Are you making sure to rotate the engine 6-7 times during the compression test? You'll see each compression bump on the gauge, typically I just count them out and then just wave my helper to stop cranking when I have the reading.

Did you follow the FSM for aligning the timing chains when you assembled it the second time?

 

yes I did but maybe I did something wrong or it jumped a tooth. I rotated it 4 or 5, or until no compression was being produced

 

I would first pull the timing cover and verify AGAIN that the timing marks are in the proper alignment as shown in the FSM. If they are then you need to start tearing the motor down.

https://www.nicoclub.com/infiniti-service-manuals

Section EM - Engine Mechanical

 

Aw man 😭😫 please just be the timing by a tooth

 

How in the world did you mange to do all of this work ( this is really involved just to change an oil pump - a lot easier to pull the engine) and then foul up the timing issue? Test of not, if you spun this engine with the starter motor, the valves are history.

 

Well it started with a blown head gasket. Bought it like that for $500 put new headgaskets, then put it back together. WALLAH took a few turns, but turned over. Ran for about 5 min at a time for a couple days. Started driving it then I got low oil pressure lamp come on. Parked it, jacked it up and took the upper oil pan, front timing cover off. Got the oil pump off, and changed it out. While thinking and scrolling for low oil pressure for about a week while changing out the oil pump thought I'd change out the oil gallery gaskets as well. Slapped it back together, but I had help from a master mechanic who mistaked the timing as well as me. Tried to start it nada. So this is where I'm at. Low compression. 😭😫 keep in mind it took me about 6 months to take it apart. I'm no master mechanic so it took me awhile looking up info in the online manual.

 

Honestly at this point I think you should start shopping for another used engine, as long as it's not the rev-up engine then you can probably find one for $500 if it's got higher miles. Pull the timing cover and verify the marks but if they look correct don't even bother digging deeper into the engine if it's something you're having to get help with like that. It would be much faster to just swap out for another motor.

If you have a 2005-2007 6MT however then you have the rev-up engine and it would probably be cheaper to rebuild the heads if it has bent valves.

 

Yeah, what a nightmare for real... I'd say new motor, and once the old one's out maybe you can mess around with getting compression back up again and getting rid of it for what you bought the "new" motor for.

 

You should also drain the oil into a very clean container, let it sit for a few hours, the drain it off into ANOTHER container and look for any "glitter" as you are slowly pouring the oil. Low oil pressure can be caused by a few things, worn/spun bearings is a common one and you'll see all sorts of glitter (metal) in the oil if it ate a bearing.

EDIT: Just trying to toss out a couple simple things to check that would indicate a blown engine so you don't spend extra time trying to repair something that's beyond your reasonable skill level.