OIL for Engine Assembly???

[Lurch2461]

Just received a set of 87mm Flat Top Forged Ross Racing Pistons and they say in the notes

 

" Lubricate pistons & rings with a premium grade oil of at least 20W/50 weight before installing in bores. Low viscosity monograde oil is not recommended"

 

I was going to use Valvoline 30 grade, but now I'm having second guesses.

 

BP Corse Plus is 25W/60, is this an option or do you use something better or more specific for assembly.

 

Thanks,

 

Dennis in Oz

[dr_hunt]

It's important to lube the rings thoroughly and wipe the bores with oil prior to installation IMO. I push the rings into the grooves exposing the ring end gap on the upside and squirt oil into the grooves of the compression rings then fill the oil expander , rotate the rings to ensure complete lubrication and then adjust rings for proper gap placement clocking on the piston prior to installation in the bores.

 

There is nothing wrong with 20-50. You want the oil to remain in the ring area rather than dribble down during the time period it takes before you start the engine IMO.

[2savage]

Remember that such instructions need to satisfy all engine builds, from a guy in New Mexico working in 100 degree plus contitions to the lunatic Canuk working in his unheated garage in winter. What the instructions are trying to convey is that the bores and rings should be well coated with nice thick oil. Since a multigrade oil has better viscous properties in a wider range of temperatures, it is more likely to stick in a think layer.

 

Hope this helps.

[Lurch2461]

Thank you, settles some thoughts. I know what I'll do now.

 

Cheers,

 

Dennis in Oz

[blueovalz]

I used (and this was on the latest rebuild) the Childs & Albert assembly lube. I was told it would assist in allowing moly rings seat more quickly, so I tried it and found the seating was almost immediate as compared to previous builds. I used it in the entire assembly and it worked very well.

[Xnke]

I've always used Bar and Chain oil for chainsaws, but so has my dad and his dad. I've never had any problems, but then again, I've only done 6 engines. Some of these guys have done 20 or 30, I'd bet!

[z-ya]

30 wt is fine. I is just for initial startup. It is more important to pre-lube the engine using the drill with a gear-less oil pump shaft method, than worrying about what oil viscosity to use for assembly. As soon as it fires, it's what is in the oil pan that matters. I use cheap 30 wt oil for initial break in and assembly (at least an hour run time). Then put a good quality conventional oil in there for the first 1000 street, or 100 track miles.