Pinfield357

i heard that motors over 100k miles shouldnt use synthetic oil... True or False??
also what oil are all of you guys using?


pinfield

dre_2ooo

I heard alot of people say that synthetic kills apex seals...

PLUS! When I got my reman. engine from Mazda, there was a big red tage that said "WARNING! USE OF SYNTHETIC OIL WILL VOID WARRANTY. "

I always use Castrol GTX (drive hard) 10W-40 (10W-30 for winters)

fc3s.org

Synthetic oils won't hurt your seals. If your motor has any leaks, even if they aren't necessarily leaking visibly, they will leak with the synthetic oil due to the properties. I noticed a 5-7degree drop with royal purple race oil in my project 86 in track conditions. The Castrol GTX is by far the most popular oil in rotaries. 10W40 for N/A and 20W50 for TII's is probably the most common viscosities used. The thicker the oil, the more oil pressure you have, but you are also now not pushing as much oil through the system due to the thickness. If you use dino oil, then just stay with it. If you have a newer motor, after breaking it in, switch to synthetic oil if you want to.

deadof_knight

i got a 183k out mine on sythetic and it ran great right up until i rebuilt it because of a cracked piece on the water oring seal

go_speed_go

Avoiding synthetic after 100K is more for boingers. At 100K, piston motors build up some carbon and sludge that are actually helping the motor seal in worn areas. Synthetic oils tend to disolve the sludge, which creates problems. Also, older engine seals may leak when exposed to synthetic.

All of this is case-by-case. I bought a 93 Nissan Maxima with 102K miles that was very well kept. I switched it to synthetic and 25K miles later, it still doesn't burn oil or leak. Gas mileage also went up 1-2 mpg.

Gene

iTrader: (1)

I thought you weren't supposed to use any synthetics in the rotary period, because the oil metering pump sprays oil into the combustion area to lube the apex seals, but of course some gets burned, and synth makes some nasty stuff when you burn it and it fuxors your apex seals...

if you disable OMP and run a premix this is moot tho

go_speed_go

Synthetic can be fully burned as long as you don't drive like a granny. Racing Beat endorses the use of synthetics.

If you do a search, you'll find plenty of debates on this topic. The dino-juice vs synthetic in rotaries is virtually a religious debate.

Pinfield357

thanks guys nex time i change my oil i will switch to castrol 20W-50

thanks alot guys and gals (if there r any)


pinfiled