Another oil pressure thread

[Peashooter67]

Oil pressure before and after the filter is
15psi out of the block from the oil pump to the filter and 8psi out of the filter.

[Peashooter67]

(11-10-2018 )snailexpress Wrote:  

(11-10-2018 )Peashooter67 Wrote:  After I check the air compressor, change oil cooler, check gears in gear case with no solution I guess it get dead headed back up to Oklahoma to the dealer for warranty.

I know I can’t drivr/run it like this.

Just my though. What if you have piece of rubber from destroyed oil filter O-ring somewhere in the oil sensor port?

From pump to oil cooler/filter is 15psi and after oil filter is 8psi... the oil goes from the pump to the oil cooler before it goes anywhere else. The pressure from the pump is at the cooler is 15 psi. So either the pump is bad “means the old pump and the new pump both had to be bad” pump shim, pick up tube or pickup tube o-ring is bad or Block has a crack.

New pump “still possible it’s bad but two different pumps with same pressure “
New pick up tube
Mew 0-ring
Verified shims are in right so most likely oil journal between pump and oil cooler is cracked.
Going to do a pressure test on this oil galley Monday.
I’m hoping it will still be the pump shim but I fear it will be the block with major internal leak.

[Peashooter67]

Thank you rawz for your help in narrowing down and verifying my issues.
I fear what I’ll have is a pile of new parts and a bad block......

Supposed to have 12/100,000 mile warranty on motor so if Block is cracked I will be putting it back together and driving it back to Cummins dealer where I bought it and make them replace block and if they refuse legal action and I’ll bring it back home and repower it with a pre emissions 14.7 Detroit. It’s a much better motor and this is coming from a caterpillar guy. I’d go with a cat but 6nz cats are way expensive.

[Rawze]

(11-10-2018 )Peashooter67 Wrote:  Thank you rawz for your help in narrowing down and verifying my issues.
I fear what I’ll have is a pile of new parts and a bad block......

Supposed to have 12/100,000 mile warranty on motor so if Block is cracked I will be putting it back together and driving it back to Cummins dealer where I bought it and make them replace block and if they refuse legal action and I’ll bring it back home and repower it with a pre emissions 14.7 Detroit. It’s a much better motor and this is coming from a caterpillar guy. I’d go with a cat but 6nz cats are way expensive.

Baah,. you could have had the same bad luck with any other used motor. Seen it plenty.

[Peashooter67]

I’ll let you know Monday or Tuesday if my fears are confirmed or not.

[Rawze]

In the case of oil some mysterious internal lower-than-normal oil pressure issues after an inframe or bearing replacements ( or if there is mysterious vibration issues ), THEY ALSO NEED TO PLASTIGAUGHE THE ROD/MAIN BEARINGS like i mentioned above! - ESPECIALLY IF THEY NO LONGER HAVE THE ORIGINAL BEARINGS TO COMPARE PART#'S TO!

I did mention this in previous post [here] above so I will elaborate...

Some ISX engines came from the factory with an over-sized connecting rod and/or main bearings. This is COMPLETELY UNPREDICTABLE and was done as the engine went down the assembly line at the factory. It could have even come from factory with DIFFERENT SIZES mid-engine!. -- If the clearances on the crank were in excess, they would switch to to a larger size connecting rod (or main) bearing, over-sizing them. This is why the bearings were not supplied in the overhaul kit (in the past any ways), as some ISX can randomly have been machined to have thicker than normal crank or rod bearings. This cannot be looked up and has to be checked only as the old ones are removed by comparing part#'s and using calipers on the old ones in the places they are not worn out. It has actually been seen in the past where they will change sizes of crank or rod bearings even from one cylinder to the next, mid engine. I remember gearhead even telling me a few years back that he got an engine to inframe once that required 2 different size bearings in it mid engine.


The engine may or may not vibrate, but usually always loose some oil pressure at idle once the oil is at temperature. - If it requires over-sized bearings, it will also not last very long, then eventually break the crank or spin a bearing. -- NEVER GUESS AT WHAT YOU GOT!-- MAKE SURE SOMEONE GOES BACK AND CHECKS THIS PROPERLY!.


part#'s are...

4089405 - Standard size connecting rod bearing kit.
4090016 - 0.010" (0.25mm) over-sized connecting rod bearing kit.
4090017 - 0.020" (0.5 mm) over-sized connecting rod bearing kit.

-- This is all assuming these bearings are "Thicker"?, for an undersized crank?. -- I have never measured, nor needed a set of them myself.

This is also true of the main bearings. There are a few sizes of of main bearings for the ISX. ON RARE OCCASION they would install the over-sized bearings from the factory. Again, why the main bearings are not supplied in the overhaul kit. Again, this could even happen mid engine.

3800298 - standard size main bearing.
4089845 - 0.010" (0.25mm) over-sized main bearings.
4089846 - 0.020" (0.5 mm) over-sized main bearings.

-- Again: This is all assuming these bearings are "Thicker"?, for an undersized crank?. -- I have never measured, nor needed a set of them myself.


-- I mentioned plastigauging the crank on my rebuild series in this video at 7:13 ...
https://youtu.be/X_HLvJfA20o

The clearance you are looking for is between 0.002" and 0.005" on the crank and/or the rod bearings. Obviously if you come up with +0.012" (greater than 0.005" per side), or perhaps even +0.022 (greater than 0.010" per side)" you need the over-size bearings. This would DEFINITELY MAKE ONE HAVE LOW OIL PRESSURE!. -- EVERY SINGLE ONE should be checked, as it could very well be that only one or 2 may have the different size bearings in them. The ISX, although not very common, has been known to come from directly factory where they re-machined a crank or bore to use the next size up bearing as needed to get the engine right.


Another reason why the OEM under-trained gaggle of "slap-it-together and get on to the next victim mentality" morons are NOT TO BE TRUSTED!.

AS TIME GOES ON, there are fewer and fewer mechanics that are properly trained on these ISX engines... it is getting pretty bad these days and only getting worse all the time. Everyone blames these engines for their problems but most always, it is some under-trained idiot that is too much in a hurry to give a damn anymore... leading to problems like this, and costing someone a fortune.

[Peashooter67]

Thank you for your sharing your knowledge and experience on this particular issue.


After we pressure test the oil journal from the oilcooler down to the oilpump assuming it doesn’t leak and/or a crack isn’t found I will have him plastigauge all the rod and mains bearings. ...............

[Peashooter67]

(11-09-2018 )Rawze Wrote:  Only thing that can cause oil pressure to be that low (8 psi) that I can think of it that it is likely internally homoraging oil badly somewhere. That or the oil filter is plugged up?

Common mistakes during an inframe just some random guesses here. Some of this it sounds like you have ruled out already ...

* oil pump shimms installed incorrectly (upside down), allowing oil to leak past them. Seen that one a few times.

* bad oil pump? - I have seen new ones with problems sometimes. Taking it apart will reveal what is wrong if it is bad internally.

* Oil filter bypass valve update installed incorrectly or o-ring shear.

* Bad oil cooler?, leaking internally?. not sure if thats possible, Have not had to take mine out yet.

* A spun bearing somewhere.

* incorrectly fitting, or damaged piston cooling nozzles.

* Bad o-ring in pickup tube, oil pump sucking air?.

* Damaged oil pump.

* Damaged internal passage in engine block?

* Air compressor bypassing too much oil ?

* The lower concept idler gear (first gear above the crank) is also positive pressure feed. A bad bearing / misalignment of sort could cause problem / low oil pressure too. The adjustable idler gear is also positive pressure fed.


* has anyone eliminated the turbo oil feed line temporarily to make sure it is not bleeding too much oil through it?


What brand of rod/main bearings were used? OEM or aftermarket?. Anyone plasitgauge the bearings for excess clearances?

Rawze sir

Oil journal pressure tests are done. Good news........ no cracks...
Doing plastigauge on rod and mains this week.

Sir

Is the creances on both rod and main bearings .002-.003?

[Rawze]

(11-15-2018 )Peashooter67 Wrote:  Rawze sir

Oil journal pressure tests are done. Good news........ no cracks...
Doing plastigauge on rod and mains this week.

Sir

Is the creances on both rod and main bearings .002-.003?

I think its 0.002" - 0.005", not sure these days.

Also, has anyone checked the rockers + rocker shafts and injector rockers + injector shafts? to make sure they are all in spec? -- excess clearances there will cause low oil pressure too.

Could also be a engine brake solenoid hemoraging oil badly too.

Just some more thoughts on it. Hopefully it will be something stupid simple that god missed during the inframe.

For all you know, there may be a bearing missing int the new head somewhere. Seen that too.