ZDDP again

[evelrod]

Just picked up several gallons of motor oil to restock from my annual oil change regatta---(well, it SEEMS like I'm sailing in a sea of oil by days end ;o( ---too many vehicles around here). I noticed that there are several brands of ZDDP additive available. Average price is around ten dollars. OK only for off road, racing, agricultural, etc.---Pre OBD stuff.
It looks like it might be the hot setup for some of our vintage, flat tappet cammed cars.

Anybody tried this additive lately? I'm still using, on my diesel and vintage engines, Castrol 20W-50 as it still (so far) has sufficient additive.

Rod

 

[romke]

for the equipment you mention i would not use supplementary additives as long as oils with the required quality are readily available. the ZDDP additives sold through consumerchannels contain usually more then 90% cheap base oil as a carrier and less then 10% actual additive - the carrier oil is needed to make sure it dissolves well when added to the oil to be "upgraded". there are two drawbacks with these additives: they are rather expensive and it is hard to tell whether they will be effective or not. the additive industry supplies a lot of different zinc/sulphur compounds aimed at various end products and various operating temperatures and with the consumer type products you will never know what you actually get. i therefore would stick to standard completely formulated oils of say the highest API quality that is not restrained in metallic additive content, like API SG or SF. Those oils will still be available for quite a long time and will contain the "classic" type of zinc-additives, since these are far cheaper then newly developed additves that can be classified as "lowSAPS". i therefore see no need for worry for flat tapped engines, since oils for that type of engine will problably around for another 10 years or so - and by then the additive industry problably has come up with even more capable "lowSAPS" alternatives.

 

[Bribyk]

Sorry to thread hi-jack but it's related.

I'm wondering about the suitability of high zinc oils for engine break-in. I know it's better for the valve train and high-contact pressure areas but is the ring/cylinder break-in improved or not?

I'm looking for a second opinion to back up or dispute what my resident engine expert is telling me. Thanks.

 

[romke]

ring cilinder break in is usually best and fastest accomplished with the oil the engine came with when new. most manufacturers use a proprietary running in oil that has been specially formulated to aid in running in and also provide the necessary extra cooling capability that is needed when running in still relatively rough surfaces. the latter is accomplished by using a slightly thinner oil then later would be advised for a given ambient temperature. the best thing you can do is use that engine oil for the full period it is advised by the manufacturer and gradually increase the load of the engine. there is an enormous variety in qualities used by various manufacturers, ranging from API SE-SM and API CF-CJ-4.

generally speaking you might say that they use the least amount of zinc possible to speed up the running in process, but still enough to withstand the loading in the valvetrain and the use as an antioxidant for the foreseen period.

if you are reconditioning engines yourself you can take the above as a guide - use the standard prescribed oil quality, perhaps one SAE grade thinner then is to be used later and gradually increase the load over time (if possible).

since drainintervals have gone up quite considerably over the last 20 years there is much less difference between service oils and running in oils then there used to be, also due to better manufacturing practices and materials the running in proces is far less critical nowadays then it used to be.

 

[evelrod]

Interesting. I've been told by folks that "should" know what they are about, that the many new cars come with the 'regular' recommended oil grade as initial, so called, break in oil. From what I have observed, that is likely something like a 5W-20 synthetic.

This much I do know for fact, the last two race engines I built last year (and the Lotus twincam I'm building now) have been run in on Castrol 20W-50 for the first warm up, about a half hour to an hour run in and tune up time. I then drain the entire system, accumulator, sump, heat exchanger and, the AN -10 lines, change the filter and, replace the lube with Redline synthetic race oil for all subsequent tune and dyno runs. To date, I have had ZERO problems...no unusual smoking or oil consumption problems and no unusual wear problems with flat tappets or DOHC.

Incidentally, I save the 'run in oil' and use it in my diesel truck...

Rod

 

[Bribyk]

I have yet to see a manufacturer recommended run-in oil for these engines and our oil supplier has no such knowledge either. We are indeed a remanufacturer so the engines are empty until we fill 'em. We can control the load rate when new though.

I did notice that another reputable builder uses "straight low-ash low-detergent 30WT oil", instead of typical 40- or multi-weight, during their break-in process. No mention of zinc though...I assume by "straight" they mean non-multi-weight but it could be construed in reference to basic or low additive.

Are there any SAE or otherwise testing procedures for break-in testing? What would you be testing to be able to say an engine was broken in well or not?

 

[patprimmer]

I use a cheaper oil for break in as I expect to run it for a short time then change to my regular synthetic oil.

I do this to flush break in and assembly contamination.

Light weight single grade makes sense as it has more slippery stuff and less additive than multi grade. Light weight flushes better.

I think anti scuff is an important characteristic in break in. I am not an expert in this field, but I would expect reasonably high ZDDP content improves anti scuff.

drwebb seems to be the expert on oil formulation. I would be interested in his views on anti scuff additives.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[romke]

in my experience european engine builders all have there own way of deciding whether an engine is run in well or not. they usually have tested various oils and dismantled the engines after a given amount of time and on the basis of those results opted for a proprietary formulation. in the past those oils usually were rather cheap single weight oils that needed to be changed somewhere between 5000 and 15000 km after the engine was put in use. since nowadays drain intervals may go up to about 160000 km far better quality oils are used and the viscosity is more in line with what would otherwise be advised.

in the reconditioning industry usually single grade oils are used for a short run in at the reconditioning plant and the engines are then shipped without oil to the enduser. the single grade oil is then usually filtered/centrifuged and used for quite some time in other rebuilt engines. in many plants the oil is seldom changed because they have sufficient top up to keep the quality at the required level.

for engine builders the actual criteria for "good" run in is that they do not get complaints about excessive oil consumption and that the engine reaches a lifespan that is greater then the warranty period. everything that happens after that is of no interest to the engine builder - but can ofcourse be important for the enduser.

i think that nowadays run in with modern engines is far less critical then it used to be - one important point to keep in mind is that, when due to poor run in, the lifespan of the engine is compromised, it will only show up when that point is reached - and that is usually many years after reconditioning.

ofcourse, when you as a reconditioner, get many complaints about excessive oil consumption or excessive valve train wear in the first year after rebuild, you might need to investigate whether there is something wrong with the way the engines are reconditioned, but generally speaking, with modern materials, the proces is not as critical as it used to be.

 

[Bribyk]

Romke, you confirmed exactly my thoughts and intentions.

 

[drwebb]

I suspect properties of supposedly special 'break-in oils' have more to do with cost than performance. The requirements (especially detergency and anti-oxicancy) for crankcase oil that only has to last 1 min.-600 miles are pretty mild, and cost savings can be significant when it is bought in bulk. Consider that many of the Sequence Tests for oil performance specify new test engines be run in on the same oil being tested for approval for service fill.

As for ZDDP, the new engine oil categories still require passing a Sequence IVA test for cam wear protection regardless of the chemistry used, and the SM requirements are more stringent than previous SL category. This makes the worry in the field over chemistry sound to me reminiscent of the changeover from leaded- to low-lead and unleaded gas. If someone believes they need more ZDDP then any top treat will need to raise the P level of the oil from whatever it is to ca. 0.10-0.14%. Most top treat oils won't disclose their level of P, leading me to concur they are formulated to deliver more 'peace of mind' to their customers than active ingredients.

 

[romke]

dr webb

you are right that cost is very important when you only use the oil for a short period, as is usually the case in a reconditioning plant. european truckbuilders however now run their engines for a period of up to several hours before mounting it in a truck - where the oil may have to last for up to 100.000 miles in actual service.

there are therefore two types of "run in" oil in use - one that merely serves to check whether the engine is tight and meets the specification requirements and another type that after that test also has to perform in actual service for quite a while. the first type is very costeffective, the second is more likely a ful blown heavy duty diesel engine oil. the same applies to gasoline engines, although in europe nowadays only full spec gasoline engine oils are used.

it seems that the term run in oil nowadays means something different then it used to be, a better term would be initial fill oil for the engine builder and a "pure" run in oil for the reconditioner. the latter would have to last only a short term and therefore has to meet far less stringent specifications.

 

[Metalguy]

For new or rebuilt engines, why not fill with the full syn. oil you're going to run? Break in engine, change filter, done.

Gold is for the mistress - silver for the maid
Copper for the craftsman cunning in his trade.
"Good!" said the Baron, sitting in his hall
But iron - cold iron is the master of them all.
Rudyard Kipling

 

[evelrod]

Since I am heavily involved in the vintage car market and am actively campaigning two vintage race cars as well as several vintage/antique vehicles, it comes as no surprise that purveyors of 'vintage' auto parts would inundate me with offers of all sort of 'snake oil'. The most recent offer was today from Moss Motors (definitely the best British car parts stores in the U.S.) is now selling a "vintage oil" with all the 'old formula' anti wear...read that ZDDP...for $5.95/qt. They also offer a small bottle of the additive itself for $9.95/bottle. I am not likely to ever avail myself of this offer, but I'll just betcha they will sell a 'ton' of it!

Rod

 

[RossABQ]

They better sell it quick, I heard that either Quaker State or Pennzoil has figured out they can sell the same oil they used to price at 99 cents/qt, for $5 a qt, and is rolling out a "vintage" blend. Can't remember which of the two it was.

 

[drwebb]

In defense of QS/Pennzoil (to whom I have no affiliation), there may be no motor oils that can still be sold for $0.99/qt as the price of the base oils alone are at or above $4/gallon. Add to that the big additive companies charge a premium to marketers for keeping 'obsolete' spec ingredients in their portfolios. Those who desire the 'peace of mind' of the 'good old oil' will have to pay a premium for the now 'specialty' products . . .

 

[evelrod]

Moss's newest addition, the engine oil at %5.95/qt is not listed on their site, yet. However, the ZDDP additive is.

ZDDPlus additive

http://www.mossmotors.com

I would guess it will sell as easily as the "oil for engines over 75,000 miles".

Rod

 

[RossABQ]

... or the oils "specially formulated for 4x4's"

 

[patprimmer]

I always wondered how the engine knew it was installed in a 4X4.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Tmoose]

I was reading some tribology book at the UMass Lowell Library. My notes are elsewhere. A section mentioned some investigation determining there being an optimum level of ZXXX to form and sustain the best wear resistant film.
Maybe 1% being optimum, and way better than 2% ??

 

[sszuch]

I have been trying to keep up with this topic and trying to make an educated choice on break in oils for strickly aircooled VW race engines. From what I have read so far, many manufacturers are reducing the ZDDP levels and, as a result, many flat tappet cams are wearing and going flat within the break in period (V8 world included). Castrol is the only company so far that I know of that has acknowleged this and is supposed to be researching the claims. I think it would be fair to suspect the higher spring rates and seat pressures many engines are now running. Some solutions are hard weld camshafts that are copper coated and parkerized or SLR treated lifters to extend camshaft / lifter life. I realize that during most break in proceedures, double or triple springs are removed to prevent unnecessary wear, but cams and lifters are still wearing to the point of replacement. This topic is out of my primary daily endeavors, maybe someone else here could better explain if the reduction in additives are truely the culprit.