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  • Everything you need to know about changing the oil on your LH.
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Everything you need to know about changing the oil on your LH.

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 #378012  by dosmalo
 March 2nd, 2019, 3:15 pm
There is a fuse that is recommended to pull before turning the engine over that allows the oil pump to charge up with oil before starting the engine such as after it has sat for a couple of weeks or more or after an oil change and was very informative.
I read a few threads on this just a week or so ago and now I can't find any of them.
Not saying they aren't here anymore just saying I'm too lazy to keep looking so I thought I would ask. :P
Thanks!
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 #378014  by FIREM
 March 2nd, 2019, 4:31 pm
First I personally do NOT think this is a good idea. Cranking speed is low and while it may build some pressure it will not deliver oil flow to vital parts of the engine. Compression resistance will squeeze oil out of the rod bearings faster than it can flow in. Cams will be oil starved during the cranking process no doubt.
Partial fill the new filter so there is some in it, not enough to drip when installing it, and fire up the engine. Idle RPM is more than adequate to provide flow and pressure very quickly.
Oil changes have been done for for countless number of years without the nonsense of this "crank for oil pressure" fad. Jiffy lube type places would be out of business if there was an issue where you need to crank first to prevent damage. I bet they never even partial fill filters, they can barley handle a pan plug without screwing up.
Now on the other hand a fresh rebuild should be pre- lubed. Either pressure lube from an outside source or with the spark plugs removed. No compression, no stress on bearings, considerably faster cranking speed are all factors why this would be an acceptable, recommended practice.
If you still plan to crank first, remove the PCM fuse, there is a map on the inside lid of the under hood Power Distribution Module.
Sneke_Eyez, remi liked this
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 #378019  by dosmalo
 March 2nd, 2019, 6:57 pm
^^Thanks for this.^^
I've always filled my filters to partial capacity for oil changes and even let the filter media soak up the oil I pour into them. The only reason I was curious about the crank procedure was my car sits for sometimes 2 - 3 weeks (or more) between outings and has attained the status of 'fair weather, Sunday driver' for the most part and even though I will drive it for an afternoon then, I'm concerned about start ups after sitting for so long.
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 #378023  by FIREM
 March 2nd, 2019, 7:24 pm
My red car, FIREM sometimes sits for a month without running, fire it up and go, may tap for a few seconds but no big deal.
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 #378061  by LUNAT1C
 March 5th, 2019, 10:16 am
Luna typically sits for a month to between startups, especially through winter. Hardly a squeek/tap/rattle (though tapping is not uncommon even with the revised rockers I installed 3.5 years ago). The black car has sat for over two years, started 2-3 times per year to keep the coolant and oil flowing, and has hardly been driven over the past almost 5 years. Sat for a month with the timing cover off last fall while I collected and installed fresh "might as well while I'm in there" parts and refurbished the cover. Put it all back together and it fired up like it ran to the store 10 minutes ago. Not even a tap, I suspect due to the fresh oil having been just poured in.

I don't partial my filter, but given it doesn't me anything but 10 seconds to do it, I may start doing that. Of course, that's impossible to do on my Jeep since the Pentastar has a top-mounted filter, so I'm uncertain how much benefit that really has given not all engines can take advantage.
 #378062  by 00R/T
 March 5th, 2019, 11:45 am
LUNAT1C wrote: March 5th, 2019, 10:16 am Luna typically sits for a month to between startups, especially through winter. Hardly a squeek/tap/rattle (though tapping is not uncommon even with the revised rockers I installed 3.5 years ago). The black car has sat for over two years, started 2-3 times per year to keep the coolant and oil flowing, and has hardly been driven over the past almost 5 years. Sat for a month with the timing cover off last fall while I collected and installed fresh "might as well while I'm in there" parts and refurbished the cover. Put it all back together and it fired up like it ran to the store 10 minutes ago. Not even a tap, I suspect due to the fresh oil having been just poured in.

I don't partial my filter, but given it doesn't me anything but 10 seconds to do it, I may start doing that. Of course, that's impossible to do on my Jeep since the Pentastar has a top-mounted filter, so I'm uncertain how much benefit that really has given not all engines can take advantage.
Granted I didn't drive it far enough to say that everything was perfect (yay self destructing brake lines!), but I started the Intrepid after it had sat for close to 3 years and it wasn't any noisier than I remembered it being the last time I had driven it. There was a bit of tapping, but it quieted right down and idled as smoothly as ever. So, I'm in agreement. I don't think this is a concern at all.

On another note - when are we gonna get to see the black car again? I miss it!
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 #378068  by LUNAT1C
 March 5th, 2019, 4:40 pm
00R/T wrote: March 5th, 2019, 11:45 am On another note - when are we gonna get to see the black car again? I miss it!
Considering I installed over $300 into the engine last fall... it will see daylight again this year once I figure out how to re-register it (had to be de-registered to avoid the pricey registration costs on a car that wasn't being driven, so it's as simple as paying the fee today and being on my way).

I plan to drive in the summer on nice cruising days. That's about it. It is't going to Carlisle or Ocean City, as we're only taking one car on trips out of town.