YAOPP - Yet another oil pressure problem

[syclone98]

After changing a timing chain, how long do you need to prime it for?

What happened with mine is that I used a priming tool but only for about 30 seconds as once I saw about 40psi on my gauge I figured that was all it needed.

After putting the cam sensor back in and firing it up, the oil pressure went up to about 80psi and then almost immediately fell back down to zero so I immediately shut the car off.

Is it possible that I just didn't prime it long enough and there's an air pocket somewhere?

I don't have the oil cooler installed so using one of those lines won't help me out.

 

[SouthernCal GN]

Just read your other thread- there's a good possibility that another piece of the old gear is lodged somewhere in the cover, or in the oil passages. Did you pull the pan and clean it out?

I really hope that's not the case!

 

[syclone98]

Yeah, I did clean out the pan very carefully after seeing how many pieces came off the timing gear.

I also checked the oil pump shaft again and it seems to be moving freely so I'm not sure what else could be wrong.

 

[Drip Pan]

I read the acronym in your title and had a flashback to "Horton Hears a Who" ("I think I hear a yip...or was it a yaopp??")

Sorry, it was a long day today.

 

[SouthernCal GN]

Did you check the passages in the cover? Did you pull the cam sensor and try a re-prime?

 

[SouthernCal GN]

I read the acronym in your title and had a flashback to "Horton Hears a Who" ("I think I hear a yip...or was it a yaopp??")

Sorry, it was a long day today.

I like your way of thinking!

 

[Chuck Leeper]

You did disassemble the pump, when you did the first cover and pan removal, right??
If you have found the pump locked up w/ a piece of the old gear, there's a good chance the tang on the shaft is fried, and/or, the drive on the cam sensor has taken a hit.[roll pin sheared] Worse than those 2, the cam gear is damaged.
Take it apart again, and clean it out, inspect ALL the pieces, and reassemble.

 

[syclone98]

No, unfortunately I completely forgot to take apart the oil pump and cover which given the amount of nylon I found floating in the pan was a pretty stupid thing to have missed.

The oil pump shaft still seems to be rotating properly so I'm going to try and reprime it tonight and see what happens. I also have the front cover from my other engine so if need be I might swap it with that one.

I'm still curious though as to how long you need to prime it. Any ideas on that? Is it actually possible to get an air pocket trapped somewhere? That seems (to me at least) like it could have caused the pressure to drop as fast as it did, in a similar fashion to having air in your brake lines.

 

[SouthernCal GN]

I always prime for at least a minute- I like to see good oil flow coming from the pushrods before I stop.

Didn't think about the cam sensor roll pin- good point, Chuck!

 

[Blown&Injected]

It is not a re-build so the engine-oil system is not dry, just the pump and filter. A short prime should be fine but IMO, when going thru all the trouble, might as well run the drill longer then it takes to pull it out and plug it in.

Is it possible that the gasket shifted and blocked something?

 

[Chuck Leeper]

Actually..

"No, unfortunately I completely forgot to take apart the oil pump and cover".
This gets you 25 lashes with a broken fan belt, no beer for a month, and the GF gets to wear your "I'm with stupid" T-shirt.... J/K. Now you know better!

Added thot..If the oil pump stopped, and the engine was running long enough to see the psi drop to 0, there HAS to be something "give".
As I mentioned above, and the shaft may have spun in the drive gear of the pump.

SUMPTIN WONG!!!

 

[SouthernCal GN]

You're heartless, dude!

 

[syclone98]

Stupid is as stupid does...

I’m not above admitting my mistakes in hopes that someone else doesn’t repeat them.

As it turns out, the reason the oil pressure suddenly dropped off is that the camshaft sensor jumped out of the motor but only just enough so that the car was still able to start.

What happened is that I had to fabricate something after misplacing the original bolt and washer and obviously didn’t do a very good job at it.

I put a much larger washer on it last night – problem solved!