Should Oil pressure go down when idle ?
Question:
– Hide quoted text — Show quoted text -> I just remove the fuel pump fuse, crank the starter until the oil > press gauge starts to rise and consider the filter is now full. > brody >You could do that, but that doesn’t sound as easy as just filling the >filter with oil. >Now, if the filter is parallel to the ground, then you might have a >problem with the filling the filter method!! >WickedSS
just got a tip from a neighbor while talking about this subject…. his truck has difficult filter access even with a dry filter, so on his first oil change, he filled his old filter with some of the used oil and dumped it into *gasp* his wife’s glass measuring cup… now he knows exactly how much oil to add, including the new filter… one of those things that’s just so simple, you don’t think of it.. *g* mac http://www.aadtonline.com/Bios%20Files/mac%20davis.htm
Response:
<snip> >Another thing you should think about is filling the new oil filter with >fresh oil before putting it on… as long as you can do that without >spilling it all over the place, like the filter is perpendicular to the >engine block… >This was actually a bulliten that was given to us techs (I used to be a >Chevy mechanic in the late 80’s early 90’s), that it prevented a "knocking >condition" when started up for the first time after an oil change. >WickedSS
IMHO, it also gives you a much better idea how much oil to add, too… no guessing what it holds "including new filter"… mac http://www.aadtonline.com/Bios%20Files/mac%20davis.htm
Response:
- Hide quoted text — Show quoted text -> <snip> > >Another thing you should think about is filling the new oil filter with > >fresh oil before putting it on… as long as you can do that without > >spilling it all over the place, like the filter is perpendicular to the > >engine block… > >This was actually a bulliten that was given to us techs (I used to be a > >Chevy mechanic in the late 80’s early 90’s), that it prevented a > "knocking > >condition" when started up for the first time after an oil change. > >WickedSS > IMHO, it also gives you a much better idea how much oil to add, too… > no guessing what it holds "including new filter"… > Who needs to guess? The owners manual specifically states how much oil to > add when changing oil AND filter. > — > Take er’ easy, > "Doc"
That doesn’t work when using a non standard sized oil filter. Or using 2 of them. BUt, you are right, in most stock cases that will help (the owners manual), but also keep in mind you are not draining all of the oil, just most of it. I just add 4 qrts and then let it sit, and check, and then fill until full. (Or 5 quarts to my Impala) WickedSS
Response:
>Who needs to guess? The owners manual specifically states how much oil to >add when changing oil AND filter.
right… i might go by what a shop manual says, but most owners manuals are useless, especially for models that have several engine/oil pan/oil cooler sizes available… i chased an overheating problem in my dak for weeks and it turned out to be air in the system that needed to be bled off… the manual made no reference to the air bleed or anything about air in the system… good thing i do newsgroups and have people like doc & mike simmons around! Happy Halloween, group!!! mac http://www.aadtonline.com/Bios%20Files/mac%20davis.htm
Response:
I just remove the fuel pump fuse, crank the starter until the oil press gauge starts to rise and consider the filter is now full. brody – Hide quoted text — Show quoted text – >Another thing you should think about is filling the new oil filter with >fresh oil before putting it on… as long as you can do that without >spilling it all over the place, like the filter is perpendicular to the >engine block… >This was actually a bulliten that was given to us techs (I used to be a >Chevy mechanic in the late 80’s early 90’s), that it prevented a "knocking >condition" when started up for the first time after an oil change. >WickedSS
Response:
> I just remove the fuel pump fuse, crank the starter until the oil > press gauge starts to rise and consider the filter is now full. > brody
You could do that, but that doesn’t sound as easy as just filling the filter with oil. Now, if the filter is parallel to the ground, then you might have a problem with the filling the filter method!! WickedSS – Hide quoted text — Show quoted text ->Another thing you should think about is filling the new oil filter with >fresh oil before putting it on… as long as you can do that without >spilling it all over the place, like the filter is perpendicular to the >engine block… >This was actually a bulliten that was given to us techs (I used to be a >Chevy mechanic in the late 80’s early 90’s), that it prevented a "knocking >condition" when started up for the first time after an oil change. >WickedSS
Response:
>> I just remove the fuel pump fuse, crank the starter until the oil > press gauge starts to rise and consider the filter is now full. > brody >You could do that, but that doesn’t sound as easy as just filling the >filter with oil. >Now, if the filter is parallel to the ground, then you might have a >problem with the filling the filter method!! >WickedSS
That method I mentioned was recommended by a mechanic friend specifically for cars with turbos since it’s critical for them that oil pressure be present at once, so I figured it would be good practice for *any* engine. brody
Response:
- Hide quoted text — Show quoted text -> RE/ > >was the gasket lubed up with some fresh > >oil? > Any reason it has to be fresh? > I’ve always used oil from the old filter – just because it’s there, > I’m there, and the new containers are up on the radiator cowl waiting > to be fed into the system. > Pete Cresswell > No, no reason, just good practice. I’ll use whatever is closest and at > times use the old stuff, but I usually use the fresh stuff. Here’s a trick, > remove the cap from one of the oil quarts and fill the cap with oil. Take > the cap underneath with ya when you’re changing the filter and use the fresh > oil on the gasket. > —
Another thing you should think about is filling the new oil filter with fresh oil before putting it on… as long as you can do that without spilling it all over the place, like the filter is perpendicular to the engine block… This was actually a bulliten that was given to us techs (I used to be a Chevy mechanic in the late 80’s early 90’s), that it prevented a "knocking condition" when started up for the first time after an oil change. WickedSS
Response:
– Hide quoted text — Show quoted text – > <snip> >Another thing you should think about is filling the new oil filter with >fresh oil before putting it on… as long as you can do that without >spilling it all over the place, like the filter is perpendicular to the >engine block… >This was actually a bulliten that was given to us techs (I used to be a >Chevy mechanic in the late 80’s early 90’s), that it prevented a "knocking >condition" when started up for the first time after an oil change. >WickedSS > IMHO, it also gives you a much better idea how much oil to add, too… > no guessing what it holds "including new filter"…
Who needs to guess? The owners manual specifically states how much oil to add when changing oil AND filter. — Take er’ easy, "Doc" Wrenchin’ since 1992 1988 GMC Sierra SLX aka "Chelsea" 1998 GMC Sonoma SLS aka "Ruby"
Response:
> Should Oil pressure go down when idle ? > Sorry for my newbie question, but I just notice that my 1997 blazer > oil pressure drops well below the half mark when idle, then goes 3/4 > back up whenever the truck is driven.
Yes, this is perfectly normal. Oil pressure varies with engine RPM’s, so the lower the RPM’s (idle) the lower the oil presure. The oil pump is driven by the camshaft via the distributor shaft which runs directly off the crankshaft. The faster the engine is turning, the faster the oil pump is turning, the higher the oil pressure. My 88′ SB V-8 sits at 30 psi idle, and 60+ psi at anything over 2000 RPM or so. > Also on a secondary note, I notice my bottom skid plate just below my > oil filter is quite wet with oil. I opened the hood, looked around > and looks nice and dry, went below the truck looked hard for any > noticeable leak and found none. Anyone here got any inputs where else > I could look for leaks ?
When the oil filter was changed, was the gasket lubed up with some fresh oil? Was the filter tightened appropriately? If the gasket wasn’t oil before assembley are under/over tightened, it would leak oil from the oil filter gasket. > MANY THANKS GUYS
– Take er’ easy, "Doc" Wrenchin’ since 1992 1988 GMC Sierra SLX aka "Chelsea" 1998 GMC Sonoma SLS aka "Ruby"
Response:
>RE/ >was the gasket lubed up with some fresh >oil? >Any reason it has to be fresh? >I’ve always used oil from the old filter – just because it’s there, >I’m there, and the new containers are up on the radiator cowl waiting >to be fed into the system. >Pete Cresswell
besides the fact that it’s a "good practice" to use fresh oil, i guess a lot would depend on the condition of the oil being drained… acids, particles, etc.??? mac http://www.aadtonline.com/Bios%20Files/mac%20davis.htm
Response:
> RE/ >was the gasket lubed up with some fresh >oil? > Any reason it has to be fresh? > I’ve always used oil from the old filter – just because it’s there, > I’m there, and the new containers are up on the radiator cowl waiting > to be fed into the system. > Pete Cresswell
No, no reason, just good practice. I’ll use whatever is closest and at times use the old stuff, but I usually use the fresh stuff. Here’s a trick, remove the cap from one of the oil quarts and fill the cap with oil. Take the cap underneath with ya when you’re changing the filter and use the fresh oil on the gasket. — Take er’ easy, "Doc" Wrenchin’ since 1992 1988 GMC Sierra SLX aka "Chelsea" 1998 GMC Sonoma SLS aka "Ruby"
Response:
– Hide quoted text — Show quoted text -> > RE/ > > >was the gasket lubed up with some fresh > > >oil? > > Any reason it has to be fresh? > > I’ve always used oil from the old filter – just because it’s there, > > I’m there, and the new containers are up on the radiator cowl waiting > > to be fed into the system. > > Pete Cresswell > No, no reason, just good practice. I’ll use whatever is closest and at > times use the old stuff, but I usually use the fresh stuff. Here’s a trick, > remove the cap from one of the oil quarts and fill the cap with oil. Take > the cap underneath with ya when you’re changing the filter and use the fresh > oil on the gasket. > — > Another thing you should think about is filling the new oil filter with > fresh oil before putting it on… as long as you can do that without > spilling it all over the place, like the filter is perpendicular to the > engine block… > This was actually a bulliten that was given to us techs (I used to be a > Chevy mechanic in the late 80’s early 90’s), that it prevented a "knocking > condition" when started up for the first time after an oil change. > WickedSS
I’ve done that for as long as I can remember on Chevy trucks. The filter being perpendicular makes this process MUCH easier! Doc
Response:
Should Oil pressure go down when idle ? Sorry for my newbie question, but I just notice that my 1997 blazer oil pressure drops well below the half mark when idle, then goes 3/4 back up whenever the truck is driven. Also on a secondary note, I notice my bottom skid plate just below my oil filter is quite wet with oil. I opened the hood, looked around and looks nice and dry, went below the truck looked hard for any noticeable leak and found none. Anyone here got any inputs where else I could look for leaks ? MANY THANKS GUYS
Response:
>Should Oil pressure go down when idle ? >Sorry for my newbie question, but I just notice that my 1997 blazer >oil pressure drops well below the half mark when idle, then goes 3/4 >back up whenever the truck is driven. >Also on a secondary note, I notice my bottom skid plate just below my >oil filter is quite wet with oil. I opened the hood, looked around >and looks nice and dry, went below the truck looked hard for any >noticeable leak and found none. Anyone here got any inputs where else >I could look for leaks ? >MANY THANKS GUYS
i’d worry more about the oil down below…. as your rpm decreases, your oil pump runs slower, so your oil pressure goes down… mac http://www.aadtonline.com/Bios%20Files/mac%20davis.htm
Response:
The oil under the filter is most likely from replacing the filter.. oil pressure drop at idle is normal. JJ
– Hide quoted text — Show quoted text ->Should Oil pressure go down when idle ? >Sorry for my newbie question, but I just notice that my 1997 blazer >oil pressure drops well below the half mark when idle, then goes 3/4 >back up whenever the truck is driven. >Also on a secondary note, I notice my bottom skid plate just below my >oil filter is quite wet with oil. I opened the hood, looked around >and looks nice and dry, went below the truck looked hard for any >noticeable leak and found none. Anyone here got any inputs where else >I could look for leaks ? >MANY THANKS GUYS > i’d worry more about the oil down below…. > as your rpm decreases, your oil pump runs slower, so your oil pressure > goes down… > mac > http://www.aadtonline.com/Bios%20Files/mac%20davis.htm
