Goodbye sweet 304

Not open for further replies.
Dec 21, 2002
Today on the way to work, my 304 V8 died.

It now has a very noisy main bearing or big end. It had been noisy at startup for some time following a stuck oil pump relief valve. I ran it as long as I could but at the end, it was banging away all the time and not just for a few seconds at startup.

Anyway, I have booked the car in for a reconditioned engine. I would like to get a big stroker but there are no funds.

They will recommend 20W-50 for the new engine so I am thinking of going Mobil 1 5W-50 (I can't find 15 - 50 full synthetic anywhere)

Thoughts ?

[ July 23, 2003, 10:44 PM: Message edited by: Andrew ]
Mobil (and other synthetic makers) recommend that synthetic oils NOT be used in remanufactured engines until a sufficent break-in period has elapsed.
Andrew, I would suggest waiting until you have about 1,000 miles (1,500 km?) before using a synthetic oil in a rebuilt motor. 15W-40 or 20W-50 conventional oil would probably be the best way to go. After the break-in period I think Mobil 1 5W-50 would work very well in a rebuilt 304 V8. Mobil 1 5W-50 is a little thinner than Mobil 1 15W-50 but the HT/HS number of 4.4 (for M1 5W-50) is about what you would get from a typical "dino" 20W-50. The HT/HS of Mobil 1 15W-50 is 5.11. I don't really see any down side to your using Mobil 1 5W-50 instead of a conventional 20W-50 (after break-in). The mobil 1 should give much better cold start performance, leave fewer deposits, and last longer as well.

[ July 24, 2003, 12:36 AM: Message edited by: Sin City ]
all my holdens used to get an oil pump primed with petroleum jelly (long way down to the oil level on these ones), and a lot of moly cam lube.

I'd fill with Valvoline XLD, start, run to 2,000 to 2,500 (to best run in the cam), run for half an hour, and dump the oil, and change filter.

Refill with XLD, drive 500km, and change again.

Do another 500, then another change.

FOr the next 1,000km, vary load, with reasonable acceleration, followed by hard deceleration (overrun).

At 2,000km, switch to whatever I was using.

M1 5W-50 should be good for it
Thanks guys.

They will probably have a "break-in" oil in there first. I will ask them.

Will do what Shannow suggests.

After break in, I will keep looking for M1 15W-50 but since it is very hard to find here, will probably go for 5W - 50

[ July 24, 2003, 03:10 AM: Message edited by: Andrew ]
I believe the 15W-50 is only sold for motorcycles (Mobil1 4T).

It's SG and SH rated.

Visc @ 40c 118cst
Visc @ 100c 17.5 cst
Pour point -51C
Flash Point 216C

The 5W-50
Visc @ 40c 102cst
Visc @ 100c 17.3 cst
Pour point -54C
Flash Point 240C

Just get the latest version of the 5W-50. The supersyn has hit Big W in the last few weeks.
Picked up the car today with new engine.

I read the service schedule for the 3 year warranty.

They must have "running in" oil in there first. The service schedule says that for the first 800 KM the car should not be idled for long periods and not driven above 90 km/h. At 800 KM, the oil and filter should be changed to the manufacturers recommended items (and with no friction modifiers for the next 5000 KM)

I stopped around the corner from the mechanic to check everything and the oil was almost clear. I really had to look hard on the dipstick to see it.

Anyway, planning to run the engine in tonight when there is no traffic.
Not open for further replies.