Hello, well i have been notecing that my oil prssure is not that good and some times goes down. So i have been thinking about changing the oil pump, the gasket, and the oil and oil filter at the same time. Is it too hard to change it , will i need to take the whole engine out? My buddys tbi, oil pump pick up got cloged and blew his motor ,so i really dont want that to happen to me. -Eric

 

unless you can figure out how to get the oil pan off, with the motor in the car, you have to pull it out.

if you do this, make sure you get a bolt in kit fot he pick-up.

 

Before you jump to any conclusions, have you hooked up a mechanical gauge to verify the oil pressure? It could be the sender going bad. It's not like that isn't an uncommon occurance. What are your bearing clearances? Making a long story short, if the oil pressure is actually verified to be low, the pump is usually not the cause.

But, if you do decide to change, even though i highly doubt it's your problem, changing the oil pump is not an every day task. You will have to raise the engine enough for the the oil pan to clear. You will be dripping oil everywhere. So working under there will be a real experience.

 

Well normally the car, at cold starts gets about 25psi, then when i have droven it enough for the engine to get to its normal temp it will hit around 10-15 psi when crusing but some times when it is ideling it will hit 0 psi and the car starts to tremble a little bit.

About the gauge i dont think it is going bad becouse when it is a 0 psi i can feel the car change.

What is the highest psi of oil can the engine hold? I got a high volume oil pump.

 

Well normally the car, at cold starts gets about 25psi, then when i have droven it enough for the engine to get to its normal temp it will hit around 10-15 psi when crusing but some times when it is ideling it will hit 0 psi and the car starts to tremble a little bit.

About the gauge i dont think it is going bad becouse when it is a 0 psi i can feel the car change.

What is the highest psi of oil can the engine hold? I got a high volume oil pump.

What else can the problem be?

 

You don't hook up a mech gauge to test the actual gauge, although you could. More commonly it is to test the functionality of the sending unit on the block. It Is extremely common, moreso than I care to say, for these to go bad.

What is the idle speed at?

 

As for what could it be, Stek has touched on it. Bearings and their clearances.

 

If you are talking about rpm wise , i havent fixed or bought a new rpm gauge so there we are stuck.

What is the highest psi this engine could be at?

 

What bearing are they? Why would bearings make you loose oil pressure?

 

When the car is idling, either in drive or park, the tach will be at a certain RPM. What RPM does it say?

As a rule of thumb, 10 psi per 1000 RPM is good, more or less.

*edit* Just verify the oil pressure. Worry about bearing clearances AFTER you verify it to be low.

 

My rpm gauge doesnt work.

 

No the mechanical guage will read the actual oil pressure rather than go through the sending unit. You could at least get a reading and guess at the rpm. Well maybe not but you could get the readings at least.

 

Oh yea, what oil and filter are you using and when was the last change? It is fouled with fuel by chance?

 

Since i bought the car it has been doing the same thing. I have owned the car for 3 months 1/2 and have changed the oil 2 times. I think the oil that i put in is valvoline but i know it is High milage and the bottle is red, With a fram oil filter.

 

Hoo boy. Persoanl opinion here. Don't use a Fram again. Try a search for the particulars.

You've owned it for a few months and changed oil a few times already. Why? Does the oil look wierd in any way. Any odd smells, like gas? Odd colors? Etc. The more info the better the help.

 

On the oil filter , witch one do you like so that next time i can use the one you prefure to me.

Well the first time i changed the oil, i did it becouse i got the car and decided to give the car a tune up so that was one of the things i changed, the second time was becouse i hit 3000 miles and changed it becouse i got board.

the only thing my car does is smoke when the car turns on for like 2 seconds , (blue smoke, 14 year old car valve seals not in the best shape). So not really any bad color in the oil, or any werad smell.

 

Devil is not alone on filter preference.

And as to why bearing clearances cause low PSI is because of the room between the bearing and the crank, either rod or main. For a used engine, what, .0015"-.003" on the mains and .001"-.002" on the rods, I'm a bit fuzzy on clearances. But if it's anything more than that, oil "flows" between them too easily. Keep in mind, resistance to "flow" (to a degree) = oil pressure. If the clearances are too loose, the oil will flow will very little, or less than normal, resistance, hence low pressure.

 

I like AC Delco, anything out of champion labs, Wix, Deutsche sometimes. Do a search and make your own decision, you may even come to the conclusion that Fram is fine.

 

I use Delco. I have a new Wix on my desk waiting to go on the engine that probably won't run again for quite some time.

 

Well then i guess i will try a acdelco. A good brand any ways. This time that i change my oil pump and oil filter i am going to be nosy and brake the oil filter and look in side.

So about the oil pump, it might not be it or what? Do they ever go bad? Does the pick up sump get cloged?

How about the cam bearings are they hard to change?

 

I still don't suspect the pump. Perhaps the installation was bad or the pickup is clogged or placed bad in relation to the pan, but i still doubt the oil pump is the cause.

How old or new is this engine? Need some background info.

 

well the engine has 132,000 miles and it is original 305. Any other back round info needed?

 

spend 15 dollars on a mechanical vacuum/pressure guage and connect where the oil sender is bolted to the block usually along the the China Wall behind the intake manifold.......its not the oilpump...they hardley fail and when they do its caused by something else...unless the pickup fell off the pump.......what weight oil are you using if its to thin it will cause the pressure to drop especially in a car with miles on where bearing clearances are not in tolerance

 

Well got the new oil pump in there. It was a little mission, but not to hard. First got all the bolts off then reallised that i had to cut the stock y pipe, then lifted the engine about 8 inches, took out the old oil pump (the pick up was cloged with black chunks of oil) cleaned every thing up put every thing back on, and now my car is running like a champ. But i guess that the sendor is going bad. But now on ideling it doesent vibrate any more. But i think that it was a good thing to do.