Question about Cars & Trucks
What is the Cat specs. for the oil press. in a 3126 Cat engine in a 938G loader
According to their website the minimum oil pressure is 41 psi at idle. I'd suggest verifying the oil pressure with a manual gauge directly plumbed to the engine. If it is 17 psi when the engine is up to temp. then you may have issues with the bearings. You should take an oil sample and find out what the metal levels are in your oil to determine if the bearings are going
Posted on Nov 27, 2012
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Slight pressure drop is likely from bearing wear. You could run a straight weight oil like sae 30, with a pint of marvel oil added.Don't use anything cheap though or it will add to the problem. The marvel oil will clean passageways just in case the pressure drop is the result of gunk in an oil galley.
You are still within the "safe margin"...minimum pressure at idle in gear, hot is 15psi (though I do not accept less than 20)
If pressure becomes steadily lower over time, either have the engine rebuilt or sell it. If you have an electric, not a mechanical gauge, you can put a mechanical one on there to verify actual pressure. Hope this helps you!!!
Posted on Apr 27, 2009
If you hear any knocking or ticking when the pressure is reading low, do not drive it 'till you have it diagnosed.
If the engine isn't noisy, you may have a pressure sending unit going bad. I'd definitely put a mechanical gauge on there just to read the actual pressure. If it is low, you may have some debris on the pump pickup screen that is obstructing oil flow Normally if it wasn't as low as yours is, I'd use an additive to dissolve the gunk but at 5psi you may do damage before the screen is clean enough so I'd recommend you remove the pan. If the mechanical gauge reads normal, replace the sender and don't bother with the remainder of what I am going to say.
If you remove the pan and find nothing on the screen, check the engine bearings for wear. If worn the correct way to repair that is to remove the engine as debris often will remain in the internal passageways and return to damage anything you put in there. Pump replacement is only necessary when you have bearing damage. Pumps do not generally fail unless they are contaminated. It will not hurt to replace one if the screen is obstructed as some debris can enter the pump and lower its pressure capacity somewhat but if the screen isn't blocked, do not blame the pump for the low pressure...you will be wasting your time and $ changing it.
Good luck...any further questions, just ask!
Posted on Mar 13, 2010
SOURCE: 1999 Z-71 with high
I dont want to be the one to bring you bad news, but you most likly have engine wear. Bearing clearances, oil pump clearances all are getting out or tollarences. you can improve this by using 15/40 mptor oil , or heaver, but that is a patch. for a long shot change the oil presure sending unit or better yet use a mechanical gauge to verify the true pressure
Posted on Jun 11, 2011
Tips for a great answer:
Jun 10, 2016 | Cars & Trucks
Mar 04, 2015 | Cars & Trucks
Jul 14, 2012 | GMC Jimmy Cars & Trucks
Jun 11, 2011 | 1999 Chevrolet Silverado 1500
May 29, 2011 | 1990 Subaru Legacy
Jan 02, 2011 | 1999 GMC Jimmy
Oct 15, 2009 | 1998 Chevrolet Camaro
Jul 15, 2009 | 1999 GMC Yukon
Dec 07, 2008 | 1998 GMC Sierra
Aug 17, 2017 | GMC Cars & Trucks
452 people viewed this question
Usually answered in minutes!