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Hello, I am trying to find a small advice right here please. My kid and his grandfather simply reconstructed a 1994 Chevy 1/2 ton 4 x 4. Everything is new however the motor(350), which ran fine. The problem is once the motor temp hits 160 degrees the oil press starts to drop from 40 pounds all the way to 15/20 pounds. The engine temp is fine and also every little thing else seems ok, just the oil push. I am wondering if it might be the manufacturing facility gauge, or probably the oil (10w/40) is also heavy/light? Or is it the worst situation scenario, a failing oil pump? I need to point out, I just reput the oil pressure sending unit and the same scenario exists.
Welcome Aboard!Even if the gauge is correct, that oil press is just fine. The general rule for a SBC is that it calls for 10 PSI for every 1,000 RPM. At an 800 RPM idle, 15 is simply fine. If you are really concerned, drainpipe the oil and also replace the filter. Install any type of oil filter you want so lengthy as it reads "Wix" or "Hastings" or "Delco" (more specifically, anypoint that does not read "Fram") and also include the correct volume of 10W30 Mobil 1 or Amsoil. The viscosity index of a PAO artificial is a lot better than that of a mineral oil through the very same base viscosity variety.
Hello, I am searching for a small advice right here please. My boy and his grandfather simply reconstructed a 1994 Chevy 1/2 ton 4 x 4. Everypoint is new however the motor(350), which ran fine. The problem is as soon as the motor temp hits 160 levels the oil pressure begins to drop from 40 pounds all the way to 15/20 pounds. The engine temp is fine and also every little thing else seems ok, just the oil pressure. I am wondering if it can be the factory gauge, or maybe the oil (10w/40) is too heavy/light? Or is it the worst case scenario, a failing oil pump? I need to mention, I just replaced the oil push sending unit and the very same scenario exists. GM recommends 10-30wt oil and actually says carry out not usage 10-40wt...as soon as the weather gets hotter , if it falls listed below this level you might find that the oil will certainly not be able to cool appropriately.....at this press it have to be ok... just how will certainly it look in summer heat ???? that will recognize if your ok
The starray thing is that as soon as you start off on the road it reads 40 and as your driving you have the right to actually watch the pressure drop. What could reason this??? And thank you in development for the short articles, this site is remarkable.
The starray thing is that as soon as you begin off on the road it reads 40 and as your driving you deserve to actually watch the push drop. What could reason this??? And give thanks to you in development for the short articles, this website is significant.The oil gets thinner as it heats up. Increased clearances as a result of wear have the right to cause pressure to bleed off much faster via lower viscosity oil, resulting in reduced press on the gauge. More than anypoint, it can be some wear. It could additionally be some sludging or carboning of the oil press relief valve in the oil pump. This last reason was the reason why my pressure progressively came up after I switched to Mobil 1 - a PAO artificial. I, myself, am running 15w50 due to the fact that I have actually 300k miles on mine, tright here has to be some rise of clearance after that many kind of miles. I had been running 20w50 dino oil (Castrol GTX) in it but, because I developed it (other than for a couple of years once I was running 15w40 Rotella).My idea is to run 15w50 Mobil 1 or Amsoil in it, readjust your filter to the non-Fram of your alternative, run it for a bit and also check out what happens. You"re most likely to view the oil revolve babsence pretty quick as PAO fabricated is very detergent and also works well at removing sludge.
The stvariety thing is that once you begin off on the road it reads 40 and as your driving you have the right to actually watch the push drop. What could cause this??? And thank you in breakthrough for the write-ups, this website is significant. after reasoning around this I currently would gain a gauge and also inspect the oil pressure ... when cold need to be 60-80psi then at normal operating temp 30-45psi....possible dash analysis is off by 20psi.....this might be simply oil sender off......
Thanks to all that responded, your help was immeasurable!!! :grinyes: What I did was change the oil and also put in an additive (Lucas engine oil treatment) I upped the oil from 10-30 to 10-40 Castrol GTX for high mileage engines through a unique anti-sludge formula. Then I adjusted the filter to a high mileage filter(not fram). Immediately the oil pressure went approximately 45 psi. When it got to 160 it never before dropped below 38 psi and has been stable since then. I told my child to store an eye on it and also if it drops dvery own aget, readjust the oil by repeating what we had just done. Its cheaper to carry out a 25 dollar oil adjust than it is to swap out a block. Thanks aget to all!!! You males are great!!:grinno: Tony N.

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Good deal, but please keep in mind that a 10w40 is around the worst oil grade you deserve to put in it. If you desire to run Castrol, 20w50 is not a bad oil to run, but save in mind that if that engine has actually a level tappet camera (which were still provided even in "94 on trucks) that you will need to put in an additive which contains ZDDP (zinc dialkyl dithio phosphate) to save the lobes on the cam from going away.