How purge old oil from filter while mounted???

[TallPaul]

Since an oil filter likely can run 10,000 or more miles before it is plugged up, I was wondering (like in the oil days of changing the filter every other OCI) if there is a way to purge the old oil from a filter while mounted on the engine block. I know I can remove, drain and remount, but would prefer to leave it on the engine as it would simplify the oil change and minimize the messy part of the change.

Maybe connect an air hose to the dip stick tube and pressurize to blow the oil out, or would that blow out my seals?

I don't want to screw things up, just get more use oil out without the mess of changing the filter.

 

[addyguy]

Short of doing a 'flush' with new oil in the sump, and then draining it, I don't think so....I wouldn't want to blow compreseed air into my engine...

 

[daves66nova]

what i sometimes do is after draining the oil,i run the engine for a few seconds so that some of the oil in the filter drains into the oil pan.That way i get more out.

 

[TallPaul]

Originally Posted By: daves66nova
what i sometimes do is after draining the oil,i run the engine for a few seconds so that some of the oil in the filter drains into the oil pan.That way i get more out.
I tired that on the Aerostar 3.0 V6 and based on the refill volume, it seems about half a quart was still in the can (I use oversized can that holds about 26 oz). So not the most efficient. Maybe run engine longer? Really, I doubt even idling for 5 minutes would hurt an engine with no oil in the pan. OTOH, without oil in the pan for the pump to suck up, how will it develop the pressure to push the oil through and out the filer??? Hate to put a sacrifical 1-2 qts in. Also danger of developing an air lock in the pickup and not getting pressure on the refill/restart.

 

[Audi Junkie]

I always dry crank my engine after draining to purge the oil pump and maybe it clears the filter too. I agree that once the filter is removed you might as well install a new one, but a drained filter is still usefull. Some cars' filter is at least $6+, so 2 oil changes of dino at 5000-6000 miles on one big filter is totally do-able. imo, draining it somehow is a must.

 

[SuperDave456]

If you really run your car THAT hard I would change the filter.

A quart or so old oil in there wont totally mess up your oil change, you are getting rid of the majority of the "spent" oil. I would think that for a around town car this would be fine.

Im thinking about how much oil stays in the engine regardless of how you drain it. I think the amount in the filter, if the filter is still good, is not that important.

Now if you drive a bunch, and you really absolutely have to drain the filter. I would think just replacing the filter would be easier.

Time for some UOA experiments!

 

[demarpaint]

I think I would rather take the filter off, and drain it, than run the engine w/o oil even for a 10 second period.

JMO,
Frank D

 

[hate2work]

Originally Posted By: demarpaint
I think I would rather take the filter off, and drain it, than run the engine w/o oil even for a 10 second period.

JMO,
Frank D


+ 1

 

[daves66nova]

what about installing a fumoto valve on the filter,hmmm?

 

[TallPaul]

Originally Posted By: daves66nova
what about installing a fumoto valve on the filter,hmmm?

Wow! That would be excellent, a drainable filter, but would only work with filters that mount straight down. Maybe can drill a hole at bottom edge and plug with RTV and a screw?

But seriously, I would like to try 2-OCI filter changes. Ha ha, 99.999% of posts in this forum are people worrying about getting good enough filtration, even to the point of spinning a new filter halfway through the OCI and here I want to go the other direction. What is it with me anyway?

 

[OVERKILL]

Originally Posted By: demarpaint
I think I would rather take the filter off, and drain it, than run the engine w/o oil even for a 10 second period.

JMO,
Frank D


+2

 

[Gary Allan]

Originally Posted By: TallPaul
Originally Posted By: daves66nova
what about installing a fumoto valve on the filter,hmmm?

Wow! That would be excellent, a drainable filter, but would only work with filters that mount straight down. Maybe can drill a hole at bottom edge and plug with RTV and a screw?

Hmm..well, if you get one of those sandwich adapters for tapping in a Frantz or just the gauges, you could get a drain valve ..heck sorta run it like you do a trans flush. Just use a couple of quarts of oil of the stuff you're going to use, throw it in the "future strategic reserve" clean container. Close your tap ..top off the sump.

 

[Chimay]

Just use some of the old filters in your stash befor they go bad.

 

[1kickbuttranger]

The best part of an oil change is spinning on the new filter. (and they're only a couple of bucks)

Many years back, I was anal about waiting a very long time for ALL the oil to drain out. But after tearing down a few engines, there is so much oil still in the block, in every valley, in all the rockers, so waiting for that last drop out of the pan to me is now pointless. I just wait till it trickles down and almost stops and put the plug back in.

 

[Audi Junkie]

Leftover oil is another reason not to push your intervals.

 

[RF Overlord]

Originally Posted By: daves66nova
after draining the oil,i run the engine for a few seconds
Holy frijoles!

Just the thought of running my motor for ANY time without oil makes me feel all verklempt.

Originally Posted By: 1kickbuttranger
waiting for that last drop out of the pan to me is now pointless. I just wait till it trickles down and almost stops and put the plug back in.
+1

 

[Colt45ws]

Im not going to change the EaO for the next change. I just wont worry about it. I figure, I will have changed around 5.5qts even without draining it.

 

[TallPaul]

Originally Posted By: 1kickbuttranger
The best part of an oil change is spinning on the new filter. (and they're only a couple of bucks)
I find the best part is pouring oil into the filler hole, and so a Patman Flush would give me opportunity to pour more oil into the filler hole.

I understand old tractors, say circa 1900, had no oil pumps, but a oil reservoir and the oil trickled down through the engine and instead of a sump, just dripped into the ground. Of course we have some leaky beaters these days that do pretty much the same thing. But just think, they did not have to do oil changes, just keep topping off. There is some merit to such a system, no?

 

[Eddie]

I let thee oil drain until it drips >1 drop per second. I do not believe in dry running my engine for any length of time. I beleve dry running can be far more dentramental that the small amout of oil removed.

 

[TallPaul]

Dry running for a half minute or so should not be a problem at all, provided the oil you had been running had sufficient levels of zddp.