Oil Change Etiquette

[solanderi]

Is there any real or theoretical risk to the motors if the oil filters are spun on dry (of course the gasket is lubed) compared to having them topped off before spinning them on (read PITA on the outboard side) ? Just curious,

Greg

 

[Genesis]

Well, zero oil pressure ain't good, and that's what you'll get for a few seconds (20, 30) on the start.

I always fill the filters. They're big.

 

[DCMY #92]

I also fill the filters on the DDs.

The filter position prevents this on my gen-set. After an oil change I hold the governor lever to prevent the RUN solinoid from pulling it to full speed. Then crank and use the governor arm like a throttle to hold speed at idle until oil pressure builds.

While doing this the RUN solinoid sees high current because the pull-in coil remains energized. This has never caused a problem with my unit, but any risk of solinoid heating can be avoided by disconnecting the solinoid wire.

 

[Trojan]

I never fill my oil filters and you really never run you motor without oil. As long as you don't race the motor you will never hurt the motor. My filters lay on there side and I'm not quite quick enough to get them on with oil in them. The oil pumps are positive displacement and they start pumping instantly the motor turns. Most oil pressure gauge takeoffs are off the cam chamber. The crank always gets the oil first so it takes a little bit of time for the gauge to register. I would never worry. Your only talking maybe 5 seconds. You have pressure to the crank long before you see it on the gauge.

BILL

 

[sammidog]

I agree with Bill. If you can fill the filters easily do it. If not, don't worry about it.

 

[Boss Lady]

You can crank them over with the fuel stops out. Most wear on the mains comes during starting. This is also why letting an engine sit is bad. The oil drains and you are getting a dry start everytime. I always crank mine over with fuel stops out. This method is harder on the batteries, but batteries are cheaper than engines.

 

[Maynard Rupp]

On our fuel dragster engines we made a screwdriver headed rod for a drill motor. Before we put the distributer in the hole we would spin the oil pump for at least 1 minute. that cycles all the shop towel lint out of the bearings and primed the whole system.
Having said that I never fill an oil filter. I don't think I was ever lucky enough to have one that sits vertical. Our Crusaders are on their side, my Yanmar diesel in our sailboat is on its side, and my Cessna 182's filter is almost completle upside down. All of these make for some swearing when they are removed.

 

[Boss Lady]

Here are some interesting links some talk about delay in lubrication and the damage caused by it.
http://ourtime.clickmediapro.com/?p=41
http://findarticles.com/p/articles/mi_m0FZX/is_n8_v63/ai_19934003
http://www.pre-luber.com/testing.htm
http://www.pre-luber.com/expertreviews.htm
http://www.sacskyranch.com/eng219.htm

 

[krush]

If u can do it easily and you wanna feel good about yourself, then go for it. There is still oil sitting on the journals and bearings from when you stopped the motor just before you changed the oil. Thus, there is still a film in there to protect the bearings and journals. There is also little load on the bearings at idle.

The "wear" everybody proclaims is almost negligible over the life of your engine. Look at your car? How many people fill up their filters on their car when changing them? How long do our car engines last? There aren't prelube pumps on jet engines.

There are much more important things to worry about IMHO, but hey, to each's own.

 

[Boss Lady]

I did my own test of STP oil treatment on a 1976 Chevy 4wd truck with a 400 cu inch small block. The engine was disassembled at 100,000 and 200,000 miles along with compression checks. I found that STP lived up to its advertizing. I sold the truck when it had 320,000 miles on it and it had just started to give off blue smoke. By the way, I thought my test was going to end early, since at about 60,000 miles I punched a hole in the oil pan while four wheeling in the mountains, and ran the engine dry, we plugged the hole with a potato, filled back up with oil and drove home. Wear on the bearings looked normal at the 100k teardown.

A sister truck that was properly maintained only achieved 110,000 miles before blue smoke forced a rebuild. Which was still a good track record for 1970's engines.

That test sold me on STP synthetic oil additive.

Oil film strength is a major issue. Out of sight, out of mind is the main problem, since we cannot easily see the damage. Just because you can't easily see it doesn't mean it isn't happening. Fleet managers have a lot of information available to them not readily available to the layman. Pre lubers and oil polishers are bigger than you may think. It is the old pay me now or pay me later. The science on all this available if you want to look for it. Whether you take this seriously or not is up to you and your wallet.

 

[SKYCHENEY]

If you can easily fill the filters, then why not do it? Mine are vertical and it takes only a few seconds to fill them. If, on the other hand, filling the filters was going to mean oil spilled all over my engine room, then I probably wouldn't do it.

 

[chris piazza]

I also fill mine but they are vertical so very easy to do. Whenever I start the engines I always "spin" them for three or four seconds with my thumb on the stop button. I have always felt that this prelube's them prior to starting.

Chris

 

[Trojan]

I don't think it makes a difference if you pre spin them or start them. There is still a load on the mains it's a diesel the compression is still there, but not as much as running. There is no compression release So the force is almost the same on the journals and rods as if running. Since it is not under a heavy load starting, the starting does not add a lot to the mains. The old ketch 22. It's what ever you prefer. If you have been setting for some time then pre spinning would probably help in as much you would be turning the crank at a lower RPM. Just my thoughts.

BILL

 

[63Connie]

our instructors at wyotech told us to NEVER fill an oil filter. It puts unfiltered oil directly into the rod and main bearings. Oil that comes out of the bottle is filtered but not to the specs as an oil filter. They have dont alot of testing on this and it has been proven to be one of the major causes of rod and main bearing failure. Some people dissagree, but nobodys forcing you to do it. Its your engine, your choice.

 

[yachtsmanbill]

My 12-71 filters are inverted, and no one on Gods green earth is fast enough to fill them !! LOL... On my gas boat, I use the main oil pump to change oil (for 30 years now!). Warm'em up, and let idle with a tube off a filter housing plug into a jug(s).. FWIW... the Merc filters are horizontaL ALSO. This arraingement makes the filters self draining BTW... ws

 

[GJH]

I think we had better specify what engines we are talking about as their needs in this area are not necessarily the same. I have DD 8v92ti's with vertical filters. DD clearly states that the filters must be filled before installing. My understanding is that the turbos are especially affected by this; interested in Karl's opinion.

Getting them on full of oil is still an awkward proposition, especially on my starboard engine. One of these days I am going to install bypass filters or find a new place to mount the current ones. I do 4 or 5 oil changes a year so it would be worth the stress reduction.

I am still searching for an elegant way to get the oil OUT of the old filters.

 

[krush]

our instructors at wyotech told us to NEVER fill an oil filter. It puts unfiltered oil directly into the rod and main bearings. Oil that comes out of the bottle is filtered but not to the specs as an oil filter. They have dont alot of testing on this and it has been proven to be one of the major causes of rod and main bearing failure. Some people dissagree, but nobodys forcing you to do it. Its your engine, your choice.

I'd say that the risk you speak of GREATLY outweighs the benefits of pre-filling the filters (simply put, I agree).

I know I've said this before, but oil pressure isn't what keeps the bearings alive--oil film does. There is still oil film on the bearings from the previous run and it will be enough to last the few seconds until the filter is filled up.

The arteries in an engine are pretty small and it doesn't take much debris to clog 'em. I've seen a TINY piece of blue shop rag wipe out then entire valve train of an engine before....

 

[Passages]

This is news to me as I have always prefilled the spin on cartridge on my DD6-71.

Any lint or minor particulate matter would only make 1 flow cycle before getting caught in the filter on the second pass.

 

[GJH]

I suggest you fill one of these big filters some time and observe where 90% of the oil goes when you do.

Next, observe how oil is actually drawn into and from the filter.

After that, ask yourself why DD tells you to fill the thing.

 

[Genesis]

I don't like empty-filter startups on turbo engines if they can be avoided.

If the filter is mounted "bottom up" you can't avoid it. But if it is mounted hanging down you can and IMHO you should.

Don't get crud in there while filling it of course. Oil from the dino factory in a sealed can is pretty darn clean; you pour it into the top of most engines over the rocker arms, flooding them, right?

(On my DDs I had a pump but the point stands in the general sense; your car's rocker cover has a cap on it, and you pour it in right over the top of 'em on its way down into the pan.)