I have the SOHC engine in a '98 Explorer with 44K miles. Oil change intervals have never exceeded 4k miles. There has always been small white plastic particles show up in the bottom of the oil drain pan with each oil change. The folks who do my oil anaylisis can not identify the white flakes. Oil anaylisis does indicate a high steel content in the oil. Ford does not know nor will they talk about what the white flakes might be. The recall that addressed timing chain tensioners was done on the vehicle at about 30k miles. The report said they were replaced but I found no evidence the engine had been entered. Anyone knowledgeable of this engine and have any idea if I have a problem? Is this one to get rid of?
tia,
ray

 

How do you know the flakes are plastic if the oil analysis couldn't identify them? Could it be aluminum? What kind of metal is showing up in the oil analysis report? I think metal flakes would suspend in the oil, particularly aluminum.

 

It would be interesting to know if the same particles are found in high quantities within the oil filter, suggesting they circulate as opposed to being localized to the oil pan. Offhand, I can think of no likely source of plastic or Teflon based components that would create this situation. Good mystery, keep us posted on your findings.

 

Oldog, I hate to tell you this, but the plastic pieces are probably from the cam chain guides. These are different from the tensioners. If the Ford dealer said they didn't know about this, they were probably lying to you. It is a very common problem in the SOHC engine, and there was an extended warranty for some model years.

The plastic guides were used in the 4.0's through build date 9-18-98.

I would take it to another dealer, and have the guides replaced. If they fail, the valves will hit the pistons and the engine is then beyond a cost-effective repair.

Good luck with it.
Don

78 Bronco Ranger XLT, 351M, 4-sp, Trailer Special

 

The white flakes are much like the old timing gear failure pieces that showed up in the early 302s except much smaller. These pieces have always been in the bottom of the drain pan. Aluminum would indeed show up in the oil annalysis but none has been detected.

 

I have cut filters, FL1A apart and found no white pieces in the filter.

 

thelonerangerxlt, Thanks for the insight on the problem. I suspected something like this. And to think I bought the SOHC engine because it was supposed to be 'the latest, greatest, and best'. I think I'll trade it on one with a 302. I know what they are.
ray

 

yeah man do it up, i heard those 5.0L in the explorer really rip especially if you have no auto 4x4... Dont know it its possibile thou.

 

Olddog, I think those chain guides were covered with an extended warranty up to 7 years/100K miles. I would take it to another dealer, and try to have it fixed. They will replace the plastic guides with aluminum ones, which are much more durable.

78 Bronco Ranger XLT, 351M, 4-sp, Trailer Special