knock after oil change, been like this last 4 changes, goes away after 1000 miles???

[williams.cory]

Ok so I have 97 Eddie Bauer with the 302. Its a great running motor and has great oil pressure. I've noticed last summer that after I changed the oil, it had a slight knock. If I raise the RPM's the knock gets faster. Its very faint and somewhat hard to hear. And the knock is kinda random, it sounds like a bunch of marbles being tumbled around. Its not a steady knocking noise (ex: knock, knock, knock knock, knock, knock, knock knock knock). If I go for a drive and get on it to get the engine hot, then the knock is gone for a couple minutes at idle then comes back. Can only be heard at idle. The knock gets quieter and quieter as time goes on, and after about 800-1000 miles I can't hear it at all. Its been doing this the last 3-4 oil changes....so what gives??

 

[williams.cory]

Oh yeah I use Valvoline 10w40 and Motorcraft filter.....


Come to think of it, since I switched over to Valvoline is when i've been noticing this noise. Its been fine on quaker state and pennzoil......hmmm

Looking at the old oil, its in great condition after 3000 miles. Still a little brown/gold if you smear some in your fingers. No metal flakes or anything in the oil.

 

[lc10135]

I have a 98 4.0 OHV that does that sometimes. It was more like a ticking noise though. I suspected sticky lifters. I been pouring in a half a can of Sea Foam in the crankcase and letting it idle for 30 min. or so, or drive it 25 to 50 miles before dropping the oil for a change and it seems to have helped?

 

[williams.cory]

I have a 98 4.0 OHV that does that sometimes. It was more like a ticking noise though. I suspected sticky lifters. I been pouring in a half a can of Sea Foam in the crankcase and letting it idle for 30 min. or so, or drive it 25 to 50 miles before dropping the oil for a change and it seems to have helped?

I've been wanting to use some sea foam but I'm afraid to with the miles I have (now 223k). About 4 days ago the noise stopped, I can no longer hear it at all and its only been around 200 miles. wtf?? must not be anything bad then....Other than that it runs great! Next time I'm using something other than Valvoline, I've never noticed this noise until I used it. What oil do you use?

 

[lc10135]

I been using resolute 5-30wt. in the winter up here in North Dakota. they make it in other weight also. I get it at Fleetfarm for around 7-8 bucks for a 5 qt. jug. I use a puralator oil filter that I buy there also for around 2 - 3 bucks. I always change the oil when it gets dirty looking on the dipstick, prolly around 2k -2.5k miles. It's cheap enough for oil & filter & I do it myself so I change more often.

 

[JCat]

IMO the noise you describe is caused by a sticking valve.

Get yourself a piece of hose and listen along your valve covers. I bet you will notice a spot where the noise is louder.

It can be caused by a weak valve spring, worn valve guide, or no lubrication getting to the valve stem.

The 302 (5.0) is known to have poor lubrication to the valvetrain....especially towards the front of the engine.

The best solution is to take the heads off and get a valve job. At 200k+ miles you are probably due for this.