Am I in trouble? Oil pressure....

[Super Blue 72]

Hi guys, thanks in advance for any info! 


I have a stock 340, never been taken apart, Rallye gauge cluster. 


I went to start the car the other day and when it usually starts up, the oil pressure (according to the factory gauge) usually right away climbs up to high on the gauge. 

This time, the engine started and it sounded like the bearings were dry for a few seconds, engine made a sort of "ka chunk" noise  and the the gauge showed there was no oil pressure, the needle didn't even budge. 

I stopped the engine and started it again and the the oil pressure slowly went up after like almost 10 seconds and hovered around the low area then after about 30 seconds it went back up to the normal high area of the gauge and has stayed there since.

The oil level is in the safe range, albeit I do need an oil change but the car isn't driven on the road, just moved around the driveway so the oil has like 2 miles  on it since a year or so.

What do you think caused the low oil pressure?  Could the shaft that drives the oil pump jump?  But if it did, why did the pressure stay low then gradually go back up to high and not just go immediately to high after the first incident of low oil pressure?


  Thanks!!!! 

[Moparal]

I dont know. Maybe the oil pressure relief valve is going bad or something of the sort

[Super Blue 72]

Thanks Alan.  I guess I was thinking shaft becaue there was a weird noise and not just the sort of "no oil in the bearings" noise.  I'll keep that pressure valve in mind.  Thanks! 

[Moparal]

2 years on an oil filter may have some draw backs. There is a relief valve or something in there. As a matter of fact, you should spin the filter off, cut it open and see if you see any debri particles in the filter. Bearing material, old silocone pieces. And it is possible the oil pick up tube picked up a piece of valve stem seal and stopped the flow for a second. When you torned the engine off, it may have floated back off and down back into the pan. My 81 318 truck pickup tube is fool of valve stem seals limiting the flow.

Checking the filter is the first thing and easiest thing for you to do.

[Super Blue 72]

Roger, boss!    Over and out!

[Chryco Psycho]

if the bypass spring / valve in the oil pump sticks open it will have very little pressure , that would be my guess

[Super Blue 72]

if the bypass spring / valve in the oil pump sticks open it will have very little pressure , that would be my guess

Thanks, Chryco! 

If that is the problem, and the car is getting normal oil pressure now, it there something to do to prevent my having to pull the oil pump?  Any tricks, like using tranny fluid in place of a quart of oil at the next oil change or something interesting like that?    Thanks!

[Chryco Psycho]

using an additive to clean the varnish out of an engine would help , I have actually drained the oil & filled the engine with a gallon of diesel fuel & let the engine idle for 1-2 minutes & then changed both the oil [diesel] & filter , the oil sure looks clean after doing that

[wally426ci]

Thats not a bad idea...... should you run a court in with the diesel to lube up at all??

[Chryco Psycho]

should be a quart of oil still in the filter unless you install a new filter twice

[LAA66]

 I would replace the pump for safety sake. If nothing else to feel comfortable about driving any distance without a breakdown. Then there is the eminent watching of the gauge and wondering too.

[422STROKER]

SB72,

You need to start putting some mileage on that thing to keep it in working order.   J/K!

I have an oil pump kicking around in the garage if you find you need one, i think they are only 25 bucks though new.  But then You'd have to pull the pan.

Tom

Let me know if you need a hand.

[Super Blue 72]

Thanks for the advice guys!  Appreciate it! 

I might just go the cleaning route.  I remember when I was younger a guy used to change our oil and his "secret" was to use a quart of tranny fluid in place of a quart of oil to loosen up varnish and what not.  The diesel fuel is an interesting idea!  I'll give it a shot! 

Tom, yanking the pan sounds like fun and all but I think I'll hold off.  Too much fun in one life time for me at this point!  Thanks much for the offer of the oil pump.   

   Yeah, one day    I'll register that car...... 

[422STROKER]

Thanks for the advice guys!  Appreciate it! 

I might just go the cleaning route.  I remember when I was younger a guy used to change our oil and his "secret" was to use a quart of tranny fluid in place of a quart of oil to loosen up varnish and what not.  The diesel fuel is an interesting idea!  I'll give it a shot! 

Tom, yanking the pan sounds like fun and all but I think I'll hold off.  Too much fun in one life time for me at this point!  Thanks much for the offer of the oil pump.   

   Yeah, one day    I'll register that car...... 

You can try Seafoam as i've hard it works well too.

Tom

[Super Blue 72]

You can try Seafoam as i've hard it works well too.

Tom

Will do!