Pre-charging filters - How important?

[Scout1]

I've never pre-charged oil filters, but keep seeing that some of you do... Now I'm beginning to wonder about it. How many of you do this and how important is it?

I always change my oil on a warm just run engine so all the engine parts have a good oil film on them for when it starts up. I hear the 3 second rattle while the oil pressure comes up then silence.

So how much damage am I doing? We all hear that start-up wear is the killer for engines, but is this an exceptionally bad time of engine wear?

All my filters are pretty much horizontal and not all that easy to get to, so I'm not sure how I could pre-charge these filters even if I wanted to! At any rate, it would likely be real messy for even a partial fill. Would it be worth it?

 

[ProfPS]

I think there is a thread on this topic in the Oil Filter forum called something like pre-soak. I don't see that there is an immediate need to do it since many OC's are done with warm engines. Being that your filter is not a verticle installation with the open end of the filter being on top, I would follow typical OC instructions with warming the engine before draining the oil. The engine will still be warm when you start the engine after completing the OC to check for leaks and it will be fine.

 

[Silber Igel]

Scout,

I don't, and haven't done it, for years and years. The only significant difference I've found is that that 'pre-charging' makes a big mess about 90% of the time and its a PITA.

I don't know how you would be able to tell if there was any damage and IF that damage was due to not 'pre-charging' the filter... too many variables.

IMHO, its another 'urban legend' that deserves a quick death....

 

[Scout1]

Thanks for the pointer... I had been searching under "pre-charge". That pre-soak thread didn't have much besides opinions.

So you agree, a warm engine pretty much eliminates the wear factor while filling the filter then? I guess all that rattling isn't doing any harm then?

 

[ProfPS]

Yes, a warm engine will also start and idle without engaging the fast idle setting or the need to apply the throttle to get it started. How long do you hear the rattling?

 

[fendertweed]

I'm in the "it can't hurt" camp on this one... I do it only as much & to the extent its convenient and doesn't make a mess. I do warm oil changes, that's def. a factor.

On a horizontal filter, I put a bit of oil in, as much as it will take without leaking out when I go to install. It takes almost no time, makes no mess and I figure something's better than nothing in there/can't hurt.

 

[BuickGN]

I wouldn't think of doing an oil change without prefilling. They say most of the bearing wear occurs during startup. You can hear the rods knocking when you don't prefill, warm or not, if it's knocking it's dry.

 

[cmhj]

Do it all the time, whenever possible of course.

 

[GMFan]

It' simple really. My filter is horizontal so I install the filter dry. I simply crank the engine 3 or 4 times to prime the filter and then the filter will be filled. Then start it up and let it run.

 

[deven]

Yep, I do the same as GMFan. I dont fill the filter with oil but just crank the engine a couple of times to prime the filter then start the engine.

 

[Scout1]

So how do you keep it from starting while you crank? Mine starts almost immediately. And if you only get a couple revolutions of the engine, seriously, how much oil could you pump with that? Certainly not enough to fill the filter could you?

 

[Scout1]

I hear the rattling for a different time on different engines. My old Ford 4.6L rattled for a couple or three seconds. My Honda is much shorter than that. Interestingly, the Ford has a much bigger filter than the little bitty filter on the Honda!

 

[aquariuscsm]

Originally Posted By: Scout1
So how do you keep it from starting while you crank? Mine starts almost immediately. And if you only get a couple revolutions of the engine, seriously, how much oil could you pump with that? Certainly not enough to fill the filter could you?


I`ve heard of people pulling the fuse that operates the fuel injectors to keep the engine from firing. Like yours,my car starts almost immediately once you turn the key.

On the filter pre-fill,I`ve always pre-filled the filter. My car never rattles or knocks on first start-up after an oil change.

 

[Hootbro]

Pre-charging is a solution in search of a actual problem. There is no documented proof than to not pre-charge will cause your engine to grenade or have any measurable wear.

Hootbro

 

[ThirdeYe]

I pre-fill my filters when I feel like it, but I never hear any rattle regardless if I fill them or not. I guess my engine's just less sensitive to that kinda thing.

 

[Bob Woods]

It can't hurt to do it.

 

[BuickGN]

Originally Posted By: Hootbro
Pre-charging is a solution in search of a actual problem. There is no documented proof than to not pre-charge will cause your engine to grenade or have any measurable wear.

Hootbro


This is surprising considering how many of us on here are OCD.

People stress over the smallest details of oil weights, additives, and intervals but that rod knock for 3-4 seconds on start up won't hurt anything. I'll spend the extra 5 seconds to pre fill my filter.

 

[Whimsey]

When I used Fram oil filters my engine sounded worse with EVERY start up than it does now that I use Motorcraft oil filters. Now it only makes the same noise for a few seconds after changing the oil. And this is ONCE every 5,000 miles, not every start. So I'm not going to sweat the brief noise ONCE during the oil change

.

Whimsey

 

[cos]

I always have prefilled. If the filter sits sideways it'll still soak up a suprising amount of oil without a drop spilling out as I spin it on.

 

[Black_Thunder]

it depends on filter sizei think.

on some diesel engines, filters can hold up to a gallon and of half of oil....some even more