i know this topic has been beat to death but.....

[502procharger]

i am thinking of switching to Synthetic oils in my new prochargerd 548. #1 am i better with st weight Synthetic oils and if so who makes the best in your opinion. i run moble 1 in all of my cars and trucks and love it but no idea if it will hold up under long hard runs in the boat. #2 if it is better to use mult visc. Synthetic oils and if so what type 20-50, 15-50, ????????????. any danger to switching on my next oil change? and do i have to do a flush or anything? sorry to bring up a topic that has been over discussed but i value everyones advise.

[Blown 472]

Jesus, talk about flogging a dead horse:D :D got a roller cam?

[502procharger]

yeah roller cam, i tried to search all oil threads but i got even more confused.

[cstraub]

Straight 40W dino. At where I work, we get a LITTLE feedback on oil.
Chris
Stef's Performance

[Blown 472]

Originally posted by 502procharger
yeah roller cam, i tried to search all oil threads but i got even more confused.
Well from what I read, ( others can chime in here too) that the sinth does not let the rollers roll on the cam rather they slide and wear the lifters and the cam.

[repo man]

Originally posted by Blown 472
Well from what I read, ( others can chime in here too) that the sinth does not let the rollers roll on the cam rather they slide and wear the lifters and the cam.
if there's not enough friction for the roller to roll how is there enough friction to wear the lifters and cam?

[Floored]

they told us that about harley roller crank bearings and its bs they still roll and my harley roller lifters still rolled and now H-D is using synthetic in newer bikes. old wives tales. they used to tell us not to use a roller tip rocker with a hydraulic cam 'cause it wouldn't roll with no lash and wear out and look how many hyd cam engines have roller tip rockers now.

[Blown 472]

Well there you have it, thanks.

[HammerDown]

More recently, I have noticed that engines with roller lifters used in the pleasure-boat environment have (exhibited undesirable wear patterns when synthetic oil is used). Specifically, because the oil is more "slippery," it appears that the rollers are sliding on the cam instead of rolling. This results in flat spots on the rollers and increased wear on the cam lobe. This problem only seems to present itself with lower valve-spring tension applications typically used with hydraulic roller cams. In race applications, with solid roller setups where 250 or more pounds of spring pressure exists when the valve is on the seat, there seems to be enough pressure to keep the roller on the lifter rolling on the cam instead of sliding.
Depending on your climate and the water temperature you typically operate your boat in, the viscosity of your oil should be selected accordingly. I believe that a straight grade SAE 40 oil is the most suitable for the majority of the performance marine engines. SAE 30 would be better for cooler climates. For extreme performance and supercharged engines, SAE 50 is suggested. Most synthetics are a multi-viscosity oil. Fuel dilution of the oil and contamination as a result of increased moisture in the crankcase seems to affect the multi-viscosity oils faster.
The most important thing is that you change your engine oil regularly and use a good quality oil. I think an oil change every 25 to 50 hours is a good idea. The higher performance your engine is, the more often the oil and filter should be changed. I use Kendall SAE 40 in all the pleasure boats in our Southern California
:cool:

[Blown 472]

Thats where I read that, I couldn't remember for the life of me.