Engine Pre-Oiler (soliciting opinions)

[acme66]

So I have been designing and building a 24v pre-oiler for our M925A1 (NHC250) and have it all done but the squealing. It is compact, robust, clever, adaptable to any truck and quite cheap if I do say so myself. I have come to a sudden crossroads however and wish to consult the hive mind.

My plan had me injecting the pressurized oil at the front and rear most block oil journal plugs on the driver side. I was using two because I felt that small size was going to limit the volume of what I could force in there. It just occurred to me however I could inject full volume oil through the oil test port on the oil cooler. Any educated opinions as to which location/method you feel would get the most oil to the important silver turny bits?

My pump is capable of 25-30psi but in all honesty I would be thrilled with just 5psi at the crank, rod and cam bearings.

Thoughts?

Ken

 

[74M35A2]

I support what you are doing, such projects are always fun, and want to add some info:

I'd question pushing pressure backward on the oil filter? Also you would have to draw oil from the pan, and would then be sending non-filtered oil to the bearings if injecting it post-filter.

We are a leader in developing idle start-stop starters, and most engines are going from 50,000 starts (10 year average of daily use), to 200,000 to 400,000 starts (same 10 year range). There have been no changes in the oiling system or bearing areas of these engines compared to conventional configurations, and we have seen zero failures in this area, across the board, from various different engine manufacturers. Many engines we have even tested multiple starters on the same engine, so the engines now have over 1 million starts on them. I truly feel, by data, that the historical myth of "all wear occurs at start up" is debunked from this observance. 1 million starts.

 

[acme66]

I pull oil from the pan, push it through a small car oil filter and inject it into the motor. Redundant check valves to prevent backflow. It will even prevent oil leaking out of the pan if god-forbid the lines were ripped off. Like I said, it is a clever system.

Are you willing to share more details? In your testing have you found any difference in the interval between starts? I assume your primary stop/start situations would be stoplights and deliveries? Does sitting for longer periods, say an hour or two change anything? Sometimes in the morning I might have 5-10 seconds of no pressure reading. Through out the day I could start it a dozen times and have pressure right there but those morning starts, you're finding that it has no measurable effect on wear? Are your systems on cars, trucks, heavy trucks or?

Ken

 

[74M35A2]

I think you'd still need to think about pushing pressure backward on the oil filter. Will it tear the pleats from the supports? Will it collapse any anti-drain back valves that are not designed to have any reverse pressure applied to them? I do know large engines like locomotives and ships do incorporate pre-lube systems before start up. I would guess these to just be an external pump, parallel to the primary mechanical pump, feeding upstream of the oil filter(s). If you have a way in before the oil filter, your system would be easier. There are also canister type pressure vessels with a solenoid on them that captures engine oil pressure when running, and can release it at next key-up. Those are another nifty way.

I'm sorry, I can't say too much more about the testing, due to the nature of my job and the protection of each customer. But, each engine is held stopped way past when the oil pressure drops to zero. So, it is a zero pressure start each time. Also, this technology is coming across the board, on everything from the smallest gasoline engines to the largest diesel ones, in vehicle applications. Even back when we were testing conventional starters, we would do numerous starters per engine, and the engine never suffered any oil starvation issues. The higher the engine load, the more oil pressure that is needed to cushion/lubricate/cool the bearings. Cranking is the lightest load, followed by engine idle, also a near-zero load on engine bearings. Drop oil pressure when going full tilt, and you'll cook bearings and have a knocker or worse in less than 3 seconds.

 

[Two Stroke Madness]

You only ever need to pre-pressurize oil into an engine that was freshly built. Using a system like the one you speak of will only increase the chance of contaminants entering the critical bearing surfaces. I've pulled apart diesel engines that were left sitting without being ran for more than ten years only to find oil film still on all the surfaces.

 

[acme66]

I am not sure I am dropping the kind of pressure needed to rip a filter apart with my pump, I was figuring however on some oil backflowing the main filter and I didn't view it as an issue, it would just get filtered again. I run NAPA and Fleetguard filters, might have to cut one open and see if backflow is built into them. I will also have to study up on the 855 oil system because for whatever reason I can not remember if there was a backflow valve in there or not. Valid points needing study.

We run a youtube channel, not a massive one but not a small one either and this pre-oiler is a project we are working on. It will get a bunch of views when done. I would like to add your information to the video but I am going to need way more than 'million starts, no increased wear, trust me' especially (and please I mean no offense to you, your information or company) when requests for more details are met with a proprietary information wall. Talk it over with whomever you need to but I would like to include it even if it means I have to show everyone why what I just built is pointless. I think we still might be talking about different things here, trying to read between the lines but it sounds like you are starting at no pressure but with a fully charged system where as I am trying to essentially pre-charge my system. Also I think you might be dealing primarily with motors designed in the last decade or two, not the 1960's boat anchor that is the 855. Anyway shoot me a line at acme66@yahoo.com if you decide it is ok to share some additional details. I will let you view and have final say on what I include of yours before publishing. So far there isn't enough here for me to do other than add something along the lines of "some people feel startup wear is over dramatized".

Also, a pair of 1/8th inch block journals or the 3/8ths monster hole that is the oil cooler sample port...? Block journals are closer to the parts I want to squirt, cooler is going to flow more.

Ken

 

[acme66]

You only ever need to pre-pressurize oil into an engine that was freshly built. Using a system like the one you speak of will only increase the chance of contaminants entering the critical bearing surfaces. I've pulled apart diesel engines that were left sitting without being ran for more than ten years only to find oil film still on all the surfaces.

IDK man when the 855 has been sitting you can hear the difference in sound when it builds pressure, the clatter and knock goes away. The idea of knocking crap in the passages loose is frightening. I have flushed some before and didn't find anything but still. Maybe that is a mark in favor of using the cooler port. Passage is so large my volume will not upset anything.

Ken

 

[Two Stroke Madness]

IDK man when the 855 has been sitting you can hear the difference in sound when it builds pressure, the clatter and knock goes away. The idea of knocking crap in the passages loose is frightening. I have flushed some before and didn't find anything but still. Maybe that is a mark in favor of using the cooler port. Passage is so large my volume will not upset anything.

Ken

That sound you hear doesn't have so much to do with oil pressure as it does with cold cylinders. It takes a minute for cylinder combustion to smooth out. I've had 6.5L GM diesels that wouldn't quiet down for close to ten minutes after start up.

 

[red]

The 855 series engines are known to last for 1 million miles before rebuild, started at least once a day pretty much every day. In my opinion it's overkill to install a pre oiler but it's not a bad idea either.

To keep the system happy and not back flow anything the oil needs to follow the same path as stock. Most oil filters have a anti drain-back feature.
Are you still running the stock canister oil filter? It would be simple to add a fitting to the canister for your pressurized oil return. That would keep the flow moving in the correct direction.

 

[wcuhillbilly]

Pre oiling on our trucks is a good idea as most of these units are now in the hobby side, and don't get run much..(same can be said for motorpool or NG units too) however I don't want to go down that rabbit hole... Whether the engine needs a prelube or not, the fact remains that the Turbos are the ones that suffer the most, the fine tolerances and the pressurized lube, gravity drain (non bath type bearings) allows the oil to fully drain out of the turbo. thus if the truck sits for a week or 6 months the turbo is running metal on metal until oil pressure is built up enough to lube the turbo... Turbos are usually fed by a hose, thus exposing them to the cold, outside of the crankcase and allowing viscosity to cool the oil upon enter the hose enroute to the turbo... ordinarily this is a good thing as we want the turbo to be cooled, however the opposite is desired on start up... cold oil does not lube, The SAE 30 that is called for in our 855 Cummins is the same as pouring raw honey out of a jar at 20*F, its a glob .... trust me I just did this on my dozer 2 weeks ago... Im switching it to 15-40w. when I turbo'd my 855 the turbo company told me that the old Cummins AR1200s were very common in failure due to farmers letting them sit for a season and then firing them up, the turbo would shell after a couple seasons due to sitting for 90% of its time with no oil in it....

 

[JDToumanian]

I just bought the 24v prelube pump below for my HEMTT... It will be pretty simple to plumb it from the pan to a port before the oil filters. I'll use a start solenoid near the pump to keep large gauge wiring to a minimum.

74M35A2's data on startup wear surprised me, but after thinking about it, it makes sense if it relates to modern engines. For example my car, and my wife's, both have oil pressure instantly upon startup. It doesn't matter if I haven't driven it in weeks, the oil pressure light goes out before the engine has even finished cranking. It's designed for light modern oils and has small oil galleries. Modern diesels are probably the same. But big, older diesels... not so much. I concur with Ken's observation of a sound change when oil pressure comes up. It's not cylinder warming, it's an instant change in sound that corresponds to the gauge showing pressure. I hear it briefly in my HEMTT (which builds oil pressure quickly) but more so in my deuce, which has a very loud and distinct change in sound and a slowing of the turbo RPM. Deuces in particular take an alarmingly long time to get oil pressure, and it has been shown that this is the cause of the all-too-common rod failures the LDT-465 engines are known for...

Jon

 

[simp5782]

On trucks that sit for awhile i just pull the stop handle and spin it for 15sec 3 or 4x then try to start it. My bypass oil system has quieted my engine down alot on excess rattle as well as oil consumption.

On a preoiler pump just tap into the access panels under the intake and run 3 nozzles. Pull your supply from the oil cooler. You pull off of that oil drain plug and you go offroad and a stick will get the best if you. Or use the port on top of the pump above the filter. That is pressure out. Use a OB1308 base. Or a spare transmission filter base and stick to #4 fittings itll be fine
Sent from my SM-G860P using Tapatalk

 

[74M35A2]

I heard LDT/S engines were designed specifically to include cold environment starting, so all of the oil drains back into the pan from the filters (where it can be heated before starting engine if needed).

Simp, if you pull oil from the oil cooler, how are you sucking it past the positive displacement oil pump? Sorry I could not buy you lunch this trip, I'll buy us both lunch next time I see you.

 

[acme66]

I was quite sure I couldn't pull oil past/through the pump and had to grab it elsewhere. I was in bed last night before I remembered why I wasn't worried about backflowing the filter, I do not think you could get any flow in reverse through the motor's pump. Same deal with grabbing oil anyplace upstream of the main pump like say the cooler though if you could that would prime the whole works. That is why I had to go spelunking. Not pulling oil from the plug, like I said, clever system. So collectively do we just not have an opinion about 2 block ports vs oil cooler? I suppose I could test.

Ken

 

[74M35A2]

My conclusion is nearly always the same: Do it up and post the results.

The pic of the pre-lube pump above looks like a traditional hydraulic pump mated to a high current DC motor (starter?). What is the pressure rating on that thing? 2700psi?

 

[JDToumanian]

The pic of the pre-lube pump above looks like a traditional hydraulic pump mated to a high current DC motor (starter?). What is the pressure rating on that thing? 2700psi?

I don't actually know the flow and pressure ratings; I wasn't able to find much info on it, even on the manufacturer's website. I do know that exact motor/pump unit is part of the pre-lube option from Caterpillar dealers, they call it PreLub / QuickEvac and it's made for Cat by RPM Industries. I just figured if it was good enough for Caterpillar it should work for me, and the price was right.

It is smaller than a starter motor... Maybe about the size of a compact car starter. I have the 12 volt version of the same motor and pump on my motorhome for the hydraulic leveling jacks so you're right about it being a rather standard hydraulic item, but maybe the pump internals differ based on the application.

Jon

 

[Jericho]

there is an easy solution that will save a lot of work, The J 69 centrifugal flow jet engine used in the T 37 tweety bird had a spring / vacuum self contained prelube in a bolt on cylinder that was about 5 inches in dia and 18 inches long, plumbs in with a discharge and return AN fitting on each end . mounts anywhere, works in any position, , they were 50 years old when they boneyarded the jet, NEVER HAD A BAD ONE, time changed them at 5000 flight hours. there were likely more than 2000 of them in the system , should be an easy find in and around Tucson AZ , Davis Monthan AFB , Bone Yard. Discharges on start, repressurizes on shut down, simple and efficient, run it in line with a simple adapter to the filter

 

[Jericho]

Having said that, most jet engines have positive displacement oil pumps and seldom run prelube any more, and most use very little oil capacity compared to the 28 gallons in a J 57 PW . , In hind sight I believe the previous assertions are correct and prelube is not needed with CORRECT viscosity and good filtration.

 

[74M35A2]

Called an accumulator. Could easily automate it with a 24v solenoid valve.

http://lightningmotorsports.com/i-298506.aspx?gclid=CIqJ8pyWgtMCFUkbaQodAbcCVg

 

[acme66]

My original prototype was an accumulator, pull out of one block port with a check valve, 24V solenoid to inject into another. After mocking it up it just seems simpler to use a pump especially since I wanted to filter the oil before putting it back. I am going to tap into the either start system to power it since I don't use that anyway. I am using a small lubrication transfer pump, like the kind service trucks might use or boat owners to pump the oil out of inboard boat motors. Guys also use them to scavenge oil from turbochargers, be nice to pump as long as I want before starting.

Ken