khamblin

Hey. So i did the engine swap a while ago, it was a rebuild with about 15k on it. It had an oil pan gasket leak and I was waiting for the warmer weather to do an oil change and do the gasket. I just got around to it about a week ago. My oil pressure used to sit around mid on the gauge, and it was low on oil, found as i did the oil change when only 3.5 liters came out. Put the new gasket on and bolted it back up put the new oil in. Now the oil pressure is up around mid sometimes, when i'm in town and stuff. But when i'm on the highway the oil pressure is really low. Just wondering if that is normal, or why it would be happening. any thoughts would be great. thanks

Flash319

Oil pressure is dependent on how fast the engine is turning. If you are on the highway you should see the highest pressure because your engine will be revving up the highest. If not you have a problem with your sending unit, oil pump, bearings........

Also what is really low? At idle on a 22re the gauge will show almost no pressure but as soon as you rev it a bit it will shoot up to half. On the highway it will sit over a half to almost the next line (2800-3300 rpm)

abecedarian

What weight oil?

Flash319

nice avatar abec...hehehe

mt_goat

Oil pressure is also temp dependent.

Cold starts = high
Hot = lower
On highway = hot
Just started after oil change = cold

khamblin

Thanks. that's what i thought... Before I did the oil change it would sit at about half on the highway, But now on the highway it is low and in town it's usually higher. Which is really not making sense to me.
I put in 10w30 oil, I don't know what people usually use, but that's what was recommended to me.
Any other thoughts? Could it have to do with a different oil filter? It had a bigger filter on before, So I'm not sure if that would make a difference...

Hadmatt54

A larger oil filter will only change the amount of oil you add to the engine to reach the full mark, it won't effect pressure, the pressure comes from your bearings and the relief valve setting in the oil pump. Guys doing engine swaps into our trucks are constantly refabricating oil pans to fit around the front housing, adding remote filter kits, etc. with no effect on oil pressure. Only the quantity of oil the engine requires is changed.
I have to ask, you repaired an oil pan leak, was there a cork gasket only, a cork gasket with a very thin layer of silicone to help with the seal or was there no gasket, only silicone and squeezed out all around the pan?
Silicone is a great tool for engine building, if it's used properly! Many back yard mechanics figure if some is good then more is better! If you had to remove gobs of the stuff or if you used a lot , there is a good chance that your pick-up tube is partially plugged. If so there is only one way to fix it, remove the oil pan and pick-up tube and clean them both out thoroughly.
Good Luck!

khamblin

When I took it off there was just the gasket, So that's all I put back on. I didn't use silicone since there wasn't any to begin. I never took the oil pan right out, I only dropped it low enough to get the oil pick up tube off to get my gasket on.

fissure333

probably the stock dummy gauge sucks. if you are worried about it change over to a mechanical gauge and see where the pressure is. hook it up right or suffer the in-cab oil leak.

jason191918

oil also loses its viscosity over time.

tried4x2signN

And you looked in the magic, yet almost Virgin, dust covered mystical book called the owners manual to confirm it's not withing manufacturers specifications?

tried4x2signN

Engine speed and? Engine speed and? Engine speed and?





kill-joy... I love the sound of desperation...

Hadmatt54

There has to be a logical reason why you have lost your oil pressure...did you put a new gasket between the block and pick-up tube when you had it apart?

khamblin

The gauge seems to work a bit. It goes up to about half when I'm driving around town, don't know if it's because of higher rpm's that it goes up. But when I'm on the highway running 3000rpm it's barely registering on the gauge. And hadmatt I did not do that. I didn't know there was a gasket that went there. When I took that pipe off it fell down into the oil pan maybe. I didnt' get the pan right off since I couldn't seem to manage. And I didn't see one on there when i took it off either so i'm not sure if there was one. I might take it off again and just make sure it is all right.

mt_goat

What engine do you have?

khamblin

I have a 1990 22re motor. Just bought it a few months ago, and it had been rebuilt about 15k before.

tried4x2signN

I'll say it another way... EVERYONE that drives a Toyota and has not seen that the oil pressure is not within specifications via THE OWNERS MANUAL, thinks their truck has low to no oil pressure.

So that's 90% all Toyota drivers... B/c I'd say 90% of ppl NEVER read the owners manual

khamblin

So you're saying that the oil pressure is supposed to be barely visible at 3000rpm?? Thats not the way it used to sit before I changed the oil, and I'm just wondering why that is. But if this is normal then something must have been messed up before.

mt_goat

Since you didn't notice the oil pickup tube to block has a gasket, listed as a non-usable part BTW (see link) I'd remove the pickup tube again and see if the gasket is there or if it fell down into the oil pan and/or replace it.

http://personal.utulsa.edu/~nathan-b...ine/9cylin.pdf

Or... at the very least do this test:

http://personal.utulsa.edu/~nathan-b...56oilpress.pdf

khamblin

Ok. I bought a oil pressure gauge today. Gonna try and get it in tomorrow. If the oil pressure is still messed then I'm gonna take the pan off again and make sure there's nothing in there and check that gasket. That oil pan is a pain to get off but if it's messed up it's worth it. Plus it won't take me as long this time since I know how to do it. Can't wait to get my 4" lift in then it'll be a piece of cake getting it off.