Hello,
I have an 83 F100 with a 300 that has almost 57000 original miles. It has a few leaks so for the last 4 or 5 oil changes I have been using 15w40 oil to help slow it down. I have changed my oil myself the last 2 times and have used valvoline heavy duty 15w40 and a purolator pure one oil filter both times. The first time I did it, the engine ran great and oil pressure always came up pretty fast. I just changed it again for the second time and used the same oil and filter and now the oil pressure takes longer to come up in the morning and it makes an awfull noise until the oil light goes out. Then when i kick the idle down it will idle normal for about 15 seconds and then i hear a faint knock but only under 1000 rpm and the engine still runs smooth the whole time, then it goes away as soon as you touch the gas. Then in less than 5 minutes the knock is gone and the engine sounds normal. It does this every time you let it sit for about 30 minutes or so but always goes away quickly. The oil light never flickers at idle or anything and i can lug it to 400 rpm and it still dosent come on. Any ideas as to what this could be? maybe a bad lifter that is taking a while to pump up? Maybe this oil filter has a faulty or missing check valve and the oil drains back to the pan and then has to pump up the lifters again every time. Thanks in advance for your ideas or help.
Josh

 

>Hello,
>I have an 83 F100 with a 300 that has almost 57000 original
>miles.

Are you POSITIVE it has 57,000 miles and not 157,000+ miles on it. As I may recall, these engines only have the 5 digit odometers and my truck says 24,000 miles but it has flipped twice , so it has 224,000 miles on it.
If it has only 57,000 on it, I am thinking the the oil filter you may have used is of inferior quality (cough...Fram...cough) or it could be as drastic as a lifter collapsing. If it is a lifter, it' not AT ALL a hard job to change them. Been there, done that.

 

[updated:LAST EDITED ON 16-Mar-02 AT 09:38 PM (EST)]Sounds like it is starving for oil on a cold start-up due to the heavy oil. I don't know where you live, but if it's fairly cold, I'd put in 10-30, with a Motorcraft filter and try that.


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'94 E-150 Conversion Van 4.9 / C-6 -- '89 Mustang LX 5.0

 

I'm voting for a faulty oil filter. I use Pure ones, also, but every now and then nearly anything mass manufactured will be subject to the occasional flaw.

 

Defintely change the filter again. This sounds like a bad filter. Also the 15w-40 oil is a little stiff if it cold where you live. Oh and a Motorcraft filter is Purlator filter and I have seen this problem on an occasional Motorcraft filter.

 

I live in florida so I think its alright to use 15w40. Pretty warm here right now! I think I am going to try to return the pure one and pick up a motorcraft. See if that helps. If it is a lifter, I gotta 262 cam with brand new lifters sitting in my garage that would take care of that problem! Thanks everyone.
Josh

 

I'd just exchange it for another Pure One I think.