Detergent vs detergent free oils

[damdcow]

Sorry if this has been covered. I searched and found a bunch of info on ZDDP (zinc) oils, but nothing on detergents.

 

Any pros and cons you guys know about? What should I be using in my fresh rebuild vs a 100,000 mile motor? 

 

Thanks for you wisdom, guys!

[ggzilla]

Its not specific to Datsuns. Look at bob the oil guy - its been discussed to death.

[TFM1066]

Non-detergent oil is used sometimes for "break in" only. Non-detergent does not suspend dirt or "hold on to it" so it can't carry it to a oil filter, you would not want to use this oil in a motor today. Detergent oil holds or can suspend "dirt" and carry it to a filter.

If you’re looking for an oil that has a high ZDDP diesel oils have the highest count as far as ppm, and their also now  available in weights other then 15-40 but that’s not a bad weight for a old Datsun.

[datzenmike]

If you have an oil filter you want a detergent oil that will hold the dirt so it can be filtered out. Non detergent allows dirt to drop to the bottom of the oil pan or stick to the block in old cars without oil pumps and filters.

[EastBay521]

nice ive been wondering about this but never got around to asking

[Driftease]

Redline makes a good brake in oil with extra zinc we use it on all of our dry clutch applications on fresh rebuilds.

[Driftease]

^^^^^sorry just realized that is not what you were asking lol.

[datzenmike]

.

nice ive been wondering about this but never got around to asking

 

I worked for this old German guy in the '80s. He has a 318 Aspen wagon. Had to use his goon on a pick up in Montreal and while gassing up checked the oil and had to add a quart. I told him when I got back and he shit the bed!!! He had been running non detergent oil forever in it. Old world ways I guess. I explained why all motors since the mid '50 ran detergent oils and why. Hell I even showed him that non detergent oils had to be special ordered because of lack of demand. (he had his own case)

 

Later in daylight I pulled the oil fill cap and looked in on the rockers. They had 1/4" of black kludge on everything. One qt. of detergent oil probably didn't hurt, but enough, or long enough and that shit would all dissolve and drop into the pan, possibly plugging the pick up and certainly the filter if not changed daily? weekly? Fack he probably never changed the filter???

 

My dad's '51 chev had no filter or oil pump and relied on splash oiling as most all early motors did. The last thing you wanted was dirt getting on the bearings so it was encouraged to collect on the block or oil pan surfaces. Oil changes had to be strictly adhered to, to remove dirt because there was no filter. NO ONE EVER gassed up without checking their oil and many people checked their oil level every day before driving! You had to. If the level fell below the spinning crankshaft, the motor seized... bang. 

 

In '62/'63 our neighbor came over and helped dad replace the main and rod bearings. The oil pan had 1/2" of thick stuff like black cheese on the bottom that had to be scrapped out. We always wondered why 4 qt. always way over filled on the dip stick. Back in the day your gas was pumped for you by a gas station attendant. Hardly ever see that today. The next thing they would ask after reg or premium was... "Check your oil?" This is how crucial it was back then.