Any mechanics on here familiar with these engines.
I’d like to see a picture of the elusive & rare Cummins 451. I’ve only heard campfire stories about them.
Here is one to wet your appetite
Oil pressure spec 40 to 60 psi at 2,000 RPM. Actual 38 To 40 at 2,000 to 2200 ish. No abnormal sounds. Idles hot Above 135f at around 20 psi any thoughts?
I’m just not familiar with this engine to know their characteristics. Is this something I can live with or should I start digging into it looking for the cause. Is there a common issues or is this most likely a bearing clearance cause.
So either you removed it to paint it, or it has been overhauled? What was done to it and when?
I purchased this bulldozer in very rough shape, it one of those stories had I known then what I know now deals. The engine starts with barely a push of the button No abnormal noises just what I consider lower oil pressure than what I expected reading the service manual. I painted the engine in place. I’m not unfamiliar with over the road Cummings engines, just not familiar with this series. I was hoping someone would tell me drop the pan and change the o-ring between the oil pump and main galley or something like that.
Hum, in my modest opinion that oil press in a hot engine is not that bad... we´re talking about 3 bar at working speed... defenitly is low but it does not mean its dangerously low. Nevertheless if u suspect something going on, a trough inspection of the oil pump and bottom bearings will give u an idea the condition. Once a saw one engine with low oil press, it blinked light at idle... but it sounded great, it happened to have the pump strainer clogged with a mix of moisture and soot and other remarkable debris that resembled dust, we cleaned the thing and its still going.
Thank you. The manual called for straight 30 W the dealer had me install 10w30. Initially the pressure was just a pinch lower than the number I stated above on the straight 30 weight. Yes I dropped the oil and filter and installed 30w. I am expected if I changed the oil to 15w40 I might see closer to the factory pressure specs of 40 to 60 at 2,000 rpm. I’m not a fan of band aiding things. Currently I have the track frames removed and the dozer up on stands if I need to drop the oil pan now would be the time. You ever have one of those moment when your discussing something and you know what you should do you just need someone to say hey if I was you I’d do xyz. This dozer has been one of those projects that just doesn’t stop. lol
Your gut is telling you to pull the pan and investigate. If it was me, and I knew it wasn’t making the low side of recommended pressure, I’d be pulling the pan and at least a couple of main caps to measure clearance, or looking for something obvious.
Yes it’s the safest way to proceed. Best case no bearing issue something like a clogged pickup
I wouldn't call running 15w40 a band aid. IMO that's the viscosity you should be running, 10w30 is too light.
Well for one thing that isn't a Cummins engine. Case built that engine on their own in Racine, WI. As far as the oil pressure goes those engines never had high oil pressure. But you can do as you please on inspection of bearings.
You beat me to it. As he said that's a Case built engine and you should be using 15w40 oil. Case didn't start using Cummins until the mid/late eighties. TGP
Sorry here, this is a me thing. It gets me that so many even the very professional out fits in their literature, as well as some my age and older can not get this correct. You are not going to find a GALLEY any place in or on an engine. That is a place on ships or airplanes to make and prepare food. Just look it up in a dictionary, the term is GALLERY. A PASSAGE WAY. And yes other definitions can be for art etc. Just look at old shop manuals and books from the past they get it right. Please excuse the lesson.
Manuals and dealer recommended 10w30
All good information thanks. I pulled some mains and a rod bearing. Appears previous engine assembly was dirty. Crank is 020/020 bearings have signs of debris embedded. The crank had minor scratch on only one of the bearing surfaces I inspected so far. Oil pump relief spring looks like it was chattering showing signs of wear on side of coils and on one end. It was worth dropping the pan. Looking at the bearing clearance specs I agree with all of you recommending 15w40. More to follow Thanks for all the great feedback