Update from NAPA Filters.. I received this letter today and it reads:
This letter is in reference to a used NAPA Gold Spin-on lube filter, part number 1348 submitted to us for review. It was reported to have been in service August 2019 on your 1997 Toyota Land Cruiser for 310 service miles. It was then forwarded to our department October 2021.
Upon receipt of the filter in the technical services department. It was subjected to a physical and dimensional evaluation and application review, an (SAE) Society of Automotive Engineers flow versus restriction test was also conducted.
The returned NAPA Gold 1348 Spin-On Lube Filter has reached its maximum contaminate holding capacity and has been operating in by-pass within the reported 310 service miles; this would not be considered normal service.
Based upon our testing and evaluation, the returned filter would be free from defects in materials and workmanship and will be returned to you.
A copy of the NAPA Filters Limited Warranty has been provided; please review the warranty service
Fi we can be of any further assistance to you in this matter, please contact us.
I filed a claim with them and this is the letter that they sent me today.
WTH is this??
People like to point their fingers at a smoking gun, but the reality is you have no real idea what caused the engine failure. Your engine had suffered a catastrophic failure (timing chain breaking). Your engine was repaired, but was it completely disassembled for cleaning? Was any metal debris, chunks of tensioner, etc.. completely cleaned and removed? Were the oil pump & pickup disassembled and inspected for damage/debris? Were all the galleries in your used cylinder head completely and thoroughly cleaned before it was installed? Were the main and connecting rod bearings inspected before the engine was buttoned up?
If you can't say "Yes" to every one of those things, then you don't really know what happened to your engine. Most likely there was debris from the initial chain failure stuck in the pick up/pump. On start up, that debris got all mashed up and sent into the filter. There, the media in the filter rapidly plugged. At that point the filter started bypassing (as it is supposed to), and started pumping metal-filled oil around your motor.
Realistically, there's only a couple of ways an oil filter can destroy your engine:
- The filter media plugs and the bypass valve doesn't open. Well, why did the media plug so quickly? Indicative of other issues with your motor, or extremely long oil change intervals.
- Extremely cold, heavy weight oil and the bypass valve doesn't open. This is a more likely scenario, but you would see low oil pressure on your dashboard at start-up if this were the case.
- Complete filter failure. As in the filter fell apart and sent chunks of filter throughout your engine. This type of failure is highly unusual, and generally not possible on filters with perforated metal cores like a Wix.
Another type of oil filter failure is the reverse of the above, where the filter goes into full-bypass and never filters any oil. This would rarely result in immediate engine failure unless something else was going wrong. Plenty of engines out there that don't even have oil filters.
