Mongo

To quiet down some never-ending lifter noise when these cars sit, I've taken it to the archives for solutions. I have used Rislone off the shelf before (the one without ZDDP as Napa Auto refuses to sell ZDDP products in my area for cars with a catalytic converter) before and was successful in quieting them down.

I ran into some threads with Greg recommending Swepco 502, which Roger carries and Rislone 4405 which contains ZDDP also. While I haven't looked up the datasheets on both products to see which is more concentrated, I'd like to get some feedback here on technically which would be the better mousetrap to use not only to unstick lifters, but to maintain proper ZDDP levels. I use Mobil 1 15w50 which does have some ZDDP in it, but I think the concentrations have been reduced (yes I have read the oil threads on here too).

Rislone 4405 appears to be cheaper to get than Swepco 502 and I just have to drive a county over to get it (small motorsports shop that stocks it). So which is better?

polecat702

Andy,
I've used Zddplus for years in both my 87, and now 89, 928's. Mobil 1 15w50 full synthetic oil, 4ozs, with every change. My car will and has set for months. Never any clatter from the lifters.

Mongo

Thanks for replying. I know this thread is probably beating a dead horse, but at least I know I have options. I have some errands this weekend out of town so I will pick up two bottles of Rislone on the way back.

oups59

I use Swepco 502 ...

jcorenman

No opinion on the additives, but look what Google found:
https://mobiloil.com/~/media/amer/us...guide-2016.pdf

Dated Feb 2016, Mobil-1 15w50 is spec'ed at 1300 ppm Zinc. This is fine without any added zinc.

hacker-pschorr

All motor oils have ZDDP.

The issue is EPA or whatever regulations about 10 years ago that reduced the level from around 1100-1200ppm to 600-800.

I don't think there is a 15w-50 on the market with less than 1100ppm anymore. Most new cars use 30 weight or lower, which is where the new regulations are targeting.

davek9

Thanks Jim, I've run the M1 15w/50 in two 928 Auto's at local DE's w/o any hot idle low oil pressure issues when returning to the pit's.
However I'm not racing and or extremely stressing the car, just having fun

For the loud / sticking tappet issue, you may want to try a lighter weight oil, say a 0W/40 or even a 10w/40 with a cleaner additive, then change the oil after a few hundred miles to flush the system.

It's expensive but less $ than removing the cams and tappets

Dave

mark kibort

I have to imagine, an oil that loses its viscosity at the level that mobil 1 does under high temps, cant support the problem discussed here.
have you tried a redline or Amsoil 20-50??

Dave, its not the coming into the pits oil pressure, and i dont know what you think is "low", but when on the track, it should be pegged at 5 bar anytime the RPM is above 2500rpm. if its not, the oil is failing.
have you tried redline or amsoil? (or some other top racing/street oil)?
we dont have tappets, we have hydralic lifters ,and if the oil gets thin.... as it does with mobil one at high temp, it can run right out of them on shut down and cause lifter noise.

my advice is try amsoil .. worth the test for sure. its an oil that doesnt break down under high temps and seems to protect well.

dr bob

Mark and for others reading along at home--

The concept of a "flat tappet" includes any cam follower that doesn't include a roller for the cam contact. Whether the car is OHC like ours with lifter as cam follower, or a 'conventional' pushrod engine with solid or hydraulic lifters that don't have rollers contacting the cam, the concept is the same. Only the location is different.

davek9

Thanks Mark, I'm not having any issues (oil pressure or noise) with my cars, I'm good.

Using the term "Tappet" as that was used in the Flat Tappet / ZDDP oil descriptions, above.

My old Jag has Solid (shimmed) Tappets, I know because I've had to shim them

Dave

mark kibort

i know "tappets" from adjusting them on BMW old 3 series and toyotas
semantics i know

mark kibort

techically, a "a tappet" is a the connection of the cam and actuating drive train that doesnt have constant contact. so, our lifters become tappets when they are not pumped up with oil. hows that for description!

olmann

I added Swepco 502 to my oil awhile back due to noisy lifters. Interestingly it is quiet when cold but noisy when hot. When hot the noise will go away around 1800 rpm. At hot idle the pressure gauge is just under 3 bar. I'm currently running Amsoil 20W-50. I'm not sure what I've got going on?

mark kibort

so thats good oil.. maybe there is some clogging of the lifters that just keeping them from pumping up properly. maybe some of those oil treatments can help.
i remember when my car was shipped to road america , it was on a truck for quite a few days... bouncing around i imagine..... i started the engine up and it made a racket until it was fully heated up. scared the heck out of me, but the fact the frequency was not "once around" , made me realize it was cam or exhaust related. at first, i thought .. rod bearings! before i have even hit the road america carocel!!

Mongo

I'm not sure if your 1990 928 has those rubber plugs at the back of the head under the valve covers, but my '87 does. There are threads about these plugs falling out, causing oil starvation issues to the chain tensioner. When I was in my car, the plugs were fine and I opted not to change them in 2013. However, can you confirm if your car really has the ticking lifters, and not a starving chain tensioner?