Here's an article that I wrote for the MGNTA.
Pre-oiling an engine should help minimize the wear that occurs at startup. The rods and mains are suspended in a “hydrodynamic wedge” of oil that is supplied by the engine oil pump with the engine running. There is no oil pressure until the engine is running. This oil pressure is what keeps the contact from occurring between the rod and main journals and their bearings. These bearings are not designed or intended for direct contact with the journals. The bearings are basically a soft metal shim.
Do we really need to be concerned about this? Well, automobile engines have been designed this way for many years and some last for hundreds of thousands of miles. One factor may be how often the engine is run and if there is any audible evidence on startup. Whether or not you can actually hear any internal engine noise at startup, it is undisputed that there is accelerated wear occurring at that time.
I believe pre-oiling will prevent wear and enhance durability. The issue is whether it’s worth the time, expense and straying from the K.I.S.S. principal. I think it’s worth the extra complexity with a simple system.
If you want to address this issue, there are several different aftermarket kits available. Some have automatic electronic controls and can also be used as a timed, turbo oil cool down, after engine shut off. These types use an expensive pump. Others have an oil accumulator/reservoir that fills from engine oil pressure when running.
There are inherent liabilities and assets with either style system and this dictates how they are used. I prefer the simplicity of the pump style. I like being able to run it for longer periods of time than the reservoir style would allow and the pump is smaller and easier to find a good mounting location.
I decided to try and put together a simple and inexpensive system. I chose a pump that was only rated for 180 degree max temp. This heat rating is not sufficient for circulating hot oil for after cooling of the turbo. I will only use this pump for pre oiling. The 3 foot length of hose that feeds it from the oil pan will be enough to insulate it from engine oil operating temps. This pump is rated for 40 psi, but it only supplies between 10 and 15 psi according to my oil pressure gauge. This is sufficient for the intended purpose.
The pump is from Northern Tool and sells for $60. It was $73 delivered to my door. It is a “SHURFLO” 8000 series, agriculture, high pressure, diaphragm pump. It is not rated for flammable liquids. This pump is similar in appearance to the ones used in the “Alky Control” kits. I like these for a couple of reasons besides the cost. They have 3/8 Female NPT inlet & outlets, and a mounting bracket that can easily be used on the front bumper support.
The rest of the parts list includes a special fitting for the oil pan drain plug. This is a swivel, to allow easy removal for oil changes and to also align it to the hose. The part number from Summit is EAR-949065ERL. This is an Earls fitting. The actual description is, 90 degree coupler, Male -6 AN to ½inch X 20. It has an O-ring on the oil pan end ($21).
You will need about 10 ft of hose. I used Aeroquip socket-less -6, about $40. Four -6 female, swivel hose ends (Brass) $4 each. Two pump fittings, I used a, 90 degree male -6 to 3/8 NPT ($8.25), and a straight male -6 to 3/8 NPT ($2). ((Socket-less hose & fittings require a special tool for assembly.))
To plumb the feed hose to your engine you have to access your Oil galley. That is located above the oil filter. It’s best to drain the coolant and remove the lower radiator hose for easy access. I remove the oil filter as well. There is a brass ”T” fitting that is male NPT into the engine block and female ¼ NPT to the oil pressure sender for the dash warning light. There is a flare fitting for the turbo oil feed at one end. You can add another brass “T” in the oil sender location. You will have to be careful to only tighten when working with NPT fittings. Plan your work so the rotation stops where you want it and do not reverse rotation even a little. You will have to use a bushing if you use 1/8 NPT fittings. 1/8 is the way to go in this small area!
I usually encourage people to eliminate their warning light in favor of an oil pressure gauge. There is little room here for much plumbing or extra fittings. I suggest a ¼ to 1/8 NPT bushing and a 1/8 brass “T” with one feed for the oil pressure gauge and the other one for the hose adaptor fitting for the pre-oiler.
This last fitting will be a straight male -6 AN to 1/8 NPT adaptor fitting ($2).
You will also need a switch, relay and some wire to hook up the electrical power, and control it. This should be less than $20.
Total for this system in parts should be around $200. Plan on a day, or at least an afternoon for installation time. Call me for tech if needed. Good luck.
Pre-oiling an engine should help minimize the wear that occurs at startup. The rods and mains are suspended in a “hydrodynamic wedge” of oil that is supplied by the engine oil pump with the engine running. There is no oil pressure until the engine is running. This oil pressure is what keeps the contact from occurring between the rod and main journals and their bearings. These bearings are not designed or intended for direct contact with the journals. The bearings are basically a soft metal shim.
Do we really need to be concerned about this? Well, automobile engines have been designed this way for many years and some last for hundreds of thousands of miles. One factor may be how often the engine is run and if there is any audible evidence on startup. Whether or not you can actually hear any internal engine noise at startup, it is undisputed that there is accelerated wear occurring at that time.
I believe pre-oiling will prevent wear and enhance durability. The issue is whether it’s worth the time, expense and straying from the K.I.S.S. principal. I think it’s worth the extra complexity with a simple system.
If you want to address this issue, there are several different aftermarket kits available. Some have automatic electronic controls and can also be used as a timed, turbo oil cool down, after engine shut off. These types use an expensive pump. Others have an oil accumulator/reservoir that fills from engine oil pressure when running.
There are inherent liabilities and assets with either style system and this dictates how they are used. I prefer the simplicity of the pump style. I like being able to run it for longer periods of time than the reservoir style would allow and the pump is smaller and easier to find a good mounting location.
I decided to try and put together a simple and inexpensive system. I chose a pump that was only rated for 180 degree max temp. This heat rating is not sufficient for circulating hot oil for after cooling of the turbo. I will only use this pump for pre oiling. The 3 foot length of hose that feeds it from the oil pan will be enough to insulate it from engine oil operating temps. This pump is rated for 40 psi, but it only supplies between 10 and 15 psi according to my oil pressure gauge. This is sufficient for the intended purpose.
The pump is from Northern Tool and sells for $60. It was $73 delivered to my door. It is a “SHURFLO” 8000 series, agriculture, high pressure, diaphragm pump. It is not rated for flammable liquids. This pump is similar in appearance to the ones used in the “Alky Control” kits. I like these for a couple of reasons besides the cost. They have 3/8 Female NPT inlet & outlets, and a mounting bracket that can easily be used on the front bumper support.
The rest of the parts list includes a special fitting for the oil pan drain plug. This is a swivel, to allow easy removal for oil changes and to also align it to the hose. The part number from Summit is EAR-949065ERL. This is an Earls fitting. The actual description is, 90 degree coupler, Male -6 AN to ½inch X 20. It has an O-ring on the oil pan end ($21).
You will need about 10 ft of hose. I used Aeroquip socket-less -6, about $40. Four -6 female, swivel hose ends (Brass) $4 each. Two pump fittings, I used a, 90 degree male -6 to 3/8 NPT ($8.25), and a straight male -6 to 3/8 NPT ($2). ((Socket-less hose & fittings require a special tool for assembly.))
To plumb the feed hose to your engine you have to access your Oil galley. That is located above the oil filter. It’s best to drain the coolant and remove the lower radiator hose for easy access. I remove the oil filter as well. There is a brass ”T” fitting that is male NPT into the engine block and female ¼ NPT to the oil pressure sender for the dash warning light. There is a flare fitting for the turbo oil feed at one end. You can add another brass “T” in the oil sender location. You will have to be careful to only tighten when working with NPT fittings. Plan your work so the rotation stops where you want it and do not reverse rotation even a little. You will have to use a bushing if you use 1/8 NPT fittings. 1/8 is the way to go in this small area!
I usually encourage people to eliminate their warning light in favor of an oil pressure gauge. There is little room here for much plumbing or extra fittings. I suggest a ¼ to 1/8 NPT bushing and a 1/8 brass “T” with one feed for the oil pressure gauge and the other one for the hose adaptor fitting for the pre-oiler.
This last fitting will be a straight male -6 AN to 1/8 NPT adaptor fitting ($2).
You will also need a switch, relay and some wire to hook up the electrical power, and control it. This should be less than $20.
Total for this system in parts should be around $200. Plan on a day, or at least an afternoon for installation time. Call me for tech if needed. Good luck.