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Does the oil filter have to be filled at oil change?

7.1K views 29 replies 8 participants last post by  doubleslottedflaps  
#1 ·
I inherited my 7.3 power stroke in my divorce, and sadly, did not get a tutorial, so I seek advice from mechanics.
I have changed the oil and not filled the filter, and it started and ran fine. This time, at the suggestion of a mechanic, I added Lucas oil stabilizer (very thick stuff). I did not fill the filter. It was a cool day (40s), started hard, ran a few seconds and died. I didn’t have time to trouble shoot so let it sit and figured I would try again when it was warmer. I tried again and it cranks but won’t start. Should I plug in the block heater awhile and get it warmed up for another try or do I need to drain the oil, start over with just oil and fill the filter this time? I don’t understand why it worked okay the last few times without filling it. One mechanic I asked said to check for a center post in the filter. I don’t understand what he’s getting at. I appreciate any suggestions you all might offer.
 
#2 ·
I inherited my 7.3 power stroke in my divorce, and sadly, did not get a tutorial, so I seek advice from mechanics.
I have changed the oil and not filled the filter, and it started and ran fine. This time, at the suggestion of a mechanic, I added Lucas oil stabilizer (very thick stuff). I did not fill the filter. It was a cool day (40s), started hard, ran a few seconds and died. I didn’t have time to trouble shoot so let it sit and figured I would try again when it was warmer. I tried again and it cranks but won’t start. Should I plug in the block heater awhile and get it warmed up for another try or do I need to drain the oil, start over with just oil and fill the filter this time? I don’t understand why it worked okay the last few times without filling it. One mechanic I asked said to check for a center post in the filter. I don’t understand what he’s getting at. I appreciate any suggestions you all might offer.
I am just a backyard mechanic. My theory is that while the engine is running and filling up the filter, the bearing could be running dry and causing excess wear. I always fill the oil filters with the oil I'm filling the vehicle with. I have nothing against Lucus products, I just use good synthetics made for the specific engine. I routinely put 250K-300K on gas engines. I am over 310K on one car and engine is finally using less than a cup of oil in 4K miles. I figure that the diesel engine is under greater pressure, and making sure it has oil all the time is a good thing. On my cars, I turn the starter over without letting the engine fire, until the oil pressure is built up, then I start and run as normal. On the 7.3 you could disconnect the CPS until oil pressure is built up and then run as normal. Just my 2cent worth advice.
 
#4 ·
For why it started then died, the 7.3 is a HEUI engine, which means it relies on oil pressure to pressurize the fuel at the injectors. No oil pressure=no run. Now, it may have run out of oil at the high pressure oil pump. Did the check engine light come on?

As far as pre filling a filter, there's a lot of debate on this. Defer to what the service manual says, as some brands say not to prefill, some say you should. I usually don't on most cars because the filters are in THE STUPIDEST and hardest places to not spill oil everywhere.
 
#11 ·
For why it started then died, the 7.3 is a HEUI engine, which means it relies on oil pressure to pressurize the fuel at the injectors. No oil pressure=no run. Now, it may have run out of oil at the high pressure oil pump. Did the check engine light come on?

As far as pre filling a filter, there's a lot of debate on this. Defer to what the service manual says, as some brands say not to prefill, some say you should. I usually don't on most cars because the filters are in THE STUPIDEST and hardest places to not spill oil everywhere.
Thank you. No check engine light and the Haynes manual says nothing about filling the filter.
 
#8 ·
along that same line of thought:
my fuel supply line was open for 8 days during a rainy season that prevented my son from finishing the Fuel Sump install. After that, he changed the Fuel Bowl filter.

He had me KOEO cycle the key ( no start attempts ) until the fuel pump quit running. we repeated that 10 times.

by that point, all air was pumped out of the Fuel Bowl, when I started it, it was just like it had been parked 10 minutes ago, click, Varoom.
 
#9 ·
Check the HPOP reservoir on top of the motor. You can check the plug with an Allen key. I don’t believe that an unfilled oil filter would cause a no start unless there is an underlying condition.

Also, what year is the truck and do you have a way to monitor conditions while cranking? If not, invest in Forscan. Otherwise you’ll just be throwing parts at it and wasting money.

This page has a list of adapters that work the best.
 
#13 ·
Thanks. I wondered about the oil pump. So do I open the plug? What am I looking for?
It’s a ‘99 and I don’t have a scanner/code reader.
Would the thick Lucas additive cause a problem? It did not want to start that first time.
 
#20 ·
I dipped the HPOP with a long match stick and there’s about 1 1/2” of dirty oil in there. I read that some people replace that too. Thoughts?
Is there a way to find out if my low pressure oil pump is operating well?
Is the Lucas Oil Stabilizer a bad idea? I read - after I put it in (stupid me) - that it causes foaming in diesels.
Lastly, would it be okay to remove the filter and fill it?
 
#19 ·
If it’s empty the low pressure oil pump will fill it. Try filling the oil filter first and adding oil to the HPOP reservoir.

just for additional information, there were two “builds” in 99, an early build (E99) and a late build (L99).
More information on that as well

 
#22 ·
The HPOP oil does not need changed as it cycles through with the rest of the oil. Doing maintenance on a regular schedule will be more effective long term. If I recall correctly, for every 1 gallon of diesel the 7.3 uses, 27 gallons of motor oil get cycled through the system.

Your best bet is a OBD2 adapter and Forscan before going down any unnecessary rabbit holes.