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Repair Questions and Answers.

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 #386269  by sdugasjr
 October 26th, 2020, 7:51 pm
Hello everyone, I have 2000 Chrysler 300m and I had my oil changed about 2,000 mi ago with Pennzoil 10-30 full synthetic. About a week 1/2 - 2 weeks ago, my oil was on the minimum fill line, so i topped it off with a qt of the same oil and carried on about my business, now today, I checked the oil to see if it was low again and sure enough, it was a bit above the minimum fill line. I noticed some oil on what I assume to be the oil cooler line when I was looking for where my oil pressure switch was, could that be a concern? Do you guys have any idea what could be causing this? Do I just need to do an oil change again (even though synthetic oil typically lasts up to 5k mi)?

Thanks in advance!
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 #386270  by M-Pressive
 October 26th, 2020, 8:02 pm
Could be leaking from the rear cam seals. Mine was leaking from there and once I swapped the o-rings it stopped.

Sounds like your cooler line is leaking as well.
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 #386271  by M-Pressive
 October 26th, 2020, 8:32 pm
Also. Valve cover gaskets could be the issue.

Any visible wet spots?
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 #386273  by LUNAT1C
 October 26th, 2020, 10:02 pm
Typical leak spots are the rear cam plate seals, MTV seal on the front of the plenum, valve cover gaskets. All of which I have done on my 2002, which has 138,000 miles.

Oil cooler lines could also be suspect where they connect to the pan and the cooler itself. It was deleted for 2002, so I’m not familiar with it.
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 #386275  by FIREM
 October 27th, 2020, 7:32 am
First thing to check/change with unexplained oil consumption is the PCV Valve. Next park in a clean area or over a fresh piece of cardboard to see if you have active leaks that drip. Last despite this being a controversial statement All Internal Combustion Engines WILL consume some oil by design. A quart in 2500 miles is not considered excessive.
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 #386276  by In-trepid
 October 27th, 2020, 8:26 am
Other than the leaks mentioned, there are two possible places that the oil may be going.
1. A leak between the oil cooling area and the engine coolant in the radiator. While this is a low probability, it is worth checking. This would generally manifest itself as either chocolate milk looking oil (which you don't appear to have) or oil in the coolant, which can be checked by looking at the coolant in the coolant reservoir when the engine is cold.
2. More likely with 146,000 miles the engine is burning the oil. This would be happening either due to valve seals that are no longer sealing optimally or oil rings on the pistons carboned up or losing pressure on the cylinder walls due to age. Chrysler engines have pretty hard steel in the cylinder walls compared to Ford or GM engines and thus a really hard time making a good seal even in new engines. As Bob noted above, your oil consumption doesn't seem out of line for an older engine.

I would check for leaks and fix them if needed. Then I would be more than happy to live with a quart in 2000 - 2500 miles of oil usage.
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 #386280  by sdugasjr
 October 27th, 2020, 10:34 am
FIREM wrote: October 27th, 2020, 7:32 am First thing to check/change with unexplained oil consumption is the PCV Valve. Next park in a clean area or over a fresh piece of cardboard to see if you have active leaks that drip. Last despite this being a controversial statement All Internal Combustion Engines WILL consume some oil by design. A quart in 2500 miles is not considered excessive.
I just changed the PCV valve not too long ago I’d say maybe less than a month ago. And there are no visible leak spots from what I can tell (the area where I park is newer flat concrete).
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 #386281  by sdugasjr
 October 27th, 2020, 10:35 am
M-Pressive wrote: October 26th, 2020, 8:02 pm Could be leaking from the rear cam seals. Mine was leaking from there and once I swapped the o-rings it stopped.

Sounds like your cooler line is leaking as well.
Does the engine have to come out to do rear cam seals? Also the valve covers look a little wet but they don’t look nearly as bad as my 99 did before I did them, and that car never had an oil consumption issue.
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 #386282  by sdugasjr
 October 27th, 2020, 10:37 am
In-trepid wrote: October 27th, 2020, 8:26 am Other than the leaks mentioned, there are two possible places that the oil may be going.
1. A leak between the oil cooling area and the engine coolant in the radiator. While this is a low probability, it is worth checking. This would generally manifest itself as either chocolate milk looking oil (which you don't appear to have) or oil in the coolant, which can be checked by looking at the coolant in the coolant reservoir when the engine is cold.
2. More likely with 146,000 miles the engine is burning the oil. This would be happening either due to valve seals that are no longer sealing optimally or oil rings on the pistons carboned up or losing pressure on the cylinder walls due to age. Chrysler engines have pretty hard steel in the cylinder walls compared to Ford or GM engines and thus a really hard time making a good seal even in new engines. As Bob noted above, your oil consumption doesn't seem out of line for an older engine.

I would check for leaks and fix them if needed. Then I would be more than happy to live with a quart in 2000 - 2500 miles of oil usage.
So you’re basically saying it’s nothing too crazy I would need to worry about? Just normal aging process on a 20 y/o engine?
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 #386284  by Sneke_Eyez
 October 27th, 2020, 12:42 pm
sdugasjr wrote: October 27th, 2020, 10:35 am
M-Pressive wrote: October 26th, 2020, 8:02 pm Could be leaking from the rear cam seals. Mine was leaking from there and once I swapped the o-rings it stopped.

Sounds like your cooler line is leaking as well.
Does the engine have to come out to do rear cam seals? Also the valve covers look a little wet but they don’t look nearly as bad as my 99 did before I did them, and that car never had an oil consumption issue.
No, the engine does not have to come out to do rear cam seals.
Honestly I'd tell anyone who hasn't done rear cam seals at this point in the life of any of these cars that they need to be done. They weep a bit of oil when they get old and harden up.
Certainly if the valve covers look wet then those need new seals as well.
Unfortunately that's one of the annoying things about an older car like this - seals wear out.
But both jobs are relatively straightforward to do, just disassembly of components.
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 #386289  by sdugasjr
 October 27th, 2020, 7:18 pm
Sneke_Eyez wrote: October 27th, 2020, 12:42 pm
sdugasjr wrote: October 27th, 2020, 10:35 am
M-Pressive wrote: October 26th, 2020, 8:02 pm Could be leaking from the rear cam seals. Mine was leaking from there and once I swapped the o-rings it stopped.

Sounds like your cooler line is leaking as well.
Does the engine have to come out to do rear cam seals? Also the valve covers look a little wet but they don’t look nearly as bad as my 99 did before I did them, and that car never had an oil consumption issue.
No, the engine does not have to come out to do rear cam seals.
Honestly I'd tell anyone who hasn't done rear cam seals at this point in the life of any of these cars that they need to be done. They weep a bit of oil when they get old and harden up.
Certainly if the valve covers look wet than those need new seals as well.
Unfortunately that's one of the annoying things about an older car like this - seals wear out.
But both jobs are relatively straightforward to do, just disassembly of components.
I’ll most likely end up taking the car on to get valve cover gasket’s done, on the sole factor that the harness was a pain to get around when I did them on my 99.
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 #386300  by hrmwrm
 October 30th, 2020, 5:21 pm
did you find your pressure switch?
they have a propensity for for springing leaks on occasion.
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 #386306  by sdugasjr
 October 31st, 2020, 2:10 pm
hrmwrm wrote: October 30th, 2020, 5:21 pm did you find your pressure switch?
they have a propensity for for springing leaks on occasion.
Yes I did but I have yet to replace it, but when I checked it (when my oil light went off, which is now back on by itself 🤨), there didn’t seem to be oil coming out from where it goes into or from the connector, unless of course I missed it, which could be a possibility as well.