Hi all,

A few years ago I noticed the common problem of my oil pressure light going off at idle after an oil change and after some digging I found that the overcomplicated oil drainback valve shattered leaving no pressure at the switch. I needed the car the next day an wasn't prepared to pay $500 at the dealer for a new filter housing so I completely plugged up the hole with a delrin plug turned down to size. Problem solved.

Fast forward to June and I decide to do a complete rebuild of my engine. While looking for various parts to order I come across the Dorman 904-261, which I guess is a "close enough" replacement for the part in the oil plug housing. I pop out my delrin plug and pop in the new part and put it all back together. You can imagine my excitement when I see the oil pressure light come on at a stop light after a few miles of driving. After being terrified of a spun bearing due to poor assembly or some other major blowout I found that the symptoms were identical to the ol' drainback plug. So, I take a look in the oil filter housing and find that the Dorman part is still there, intact.

After looking around on the forum I have found more complaints than successes, such as this thread here:

https://www.northamericanmotoring.co...y-on-idle.html

Has anyone had any success with these Dorman drainback valves? Are there more successes than failures?

 

An update:

I installed a oil pressure gauge and found that I have <5 psi pressure at 3k revs, despite what the pressure switch was telling me. No good.

I bought this part here and installed it: https://www.outmotoring.com/MINI-Coo...rep_12345.html . Boom. 50psi on cold startup.

I truly want to cry thinking about the damage that was done to my engine with that piece of s*** dorman part. No oil for 50 miles on a brand new engine that took me 5 months to build. I guess I am the one to blame. I should have had the pressure gauge at the start. My oil looked like glitter after draining it, which I can only assume is the bearing babbit. I think I might roll with it as my oil pressure still looks good, but I will be doing oil changes every 50 miles until the oil comes out clean. I might take off the bottom end in situ to see how bad the damage is.

If anyone in the future is trying to fix their idle-oil pressure issue, do yourself a favor and stay away from the dorman drainback valve. You should at least try the part linked above- I believe this part was designed and built by a member of this forum so that's neat. I'll update this thread if it ever goes bad, and at what mileage. Presuming my engine doesn't blow up by then.

 

Dude that’s crazy! Thank you for posting 🙏

 

The 50 mile oil changes until clear thing is not a bad idea, although that's going to get pricey in a hurry with the filters and oil. Would NOT flush the motor with anything. If you're handy and have the tools might want to drop the pan and have a look at the rod bearings. The good news is your engine was fairly fresh when this happened so you should have had plenty of 'meat on the bone' to go through before actual failure ensued (spun bearings etc). You caught it early, so would * think * you can be somewhat optimistic at this point. Good luck with this; hope it comes out okay.

Thanks for posting this feedback about the Dorman vs the Outmotoring solution, very valuable for the rest of us. My original factory plunger is still intact (I inspect it every oil change - 3K or twice a year minimum) but I plan to buy an Outmotoring replacement soon for my pack up kit; just not sure whether I should replace it pre-emptively at this point or not.

 

I wouldn't replace it pre-emptively. I'm pretty sure every case of these failing is during an oil change. Just be careful when you pull your filter, and check to see the plastic top hat is still there. After you start it up make sure you get it to temp so the idle drops to 800. Typically the oil light goes out a hair past idle.

Does anyone know the purpose of the drainback valve? The only reason I can think of is if your oil filter is so clogged that the oil pressure pushes up the filter to let it drain back to the pan. That's why I plugged it before my rebuild.