Hydrocruiser

I put this together a while back..

Oil Filter f/ most Mercruisers
FYI:The thread type on the filter is 13/16-16.
Fram: PH5, HP4, DG5, PH13 (no anti drainback) Pureolator: L34631
Purolator Pure One: PL34631
AC: PF1218, PF932
Motorcraft: FL-12A
NAPA: 1060, 1060gold
Wix: 51060
Wix Racing: 51060R, 51061R R= Racing
K&N: HP3002
Baldwin: B1428 (Top Rated)
Amsoil: SDF-24
Hastings: LF279
Fleetguard: LF3679
Mercruiser: 35-802885Q
Mobil 1: M1-302 or M1-111
Kendall: K31
Penzoil: PZ45
Quaker State: QS5
Shell: S63, SH38
Texaco: T38, T38B
Warner: PH1218
STP: S01218
Valvoline: V056

Hydrocruiser

Here is the deal...

I know 4 guys using Royal Purple Gearmax and love it

3 who use Redline Shockproof Heavy and swear by it.

Several using Mobil-1 and getting great results.

A few using Amsoil who think it is "thinner" and gives an extra 1 mph.

Many who have a love/hate relationship with Merc HP.


The problem is I do not see any one product being the end all. I do like the seal conditioners in Amsoil's new product however more than the rest. It may keep seals intact better and longer and water out better too. That is a huge benefit as I see it.

So the bottom line is...in this department Mercury has a captured audience and HP is a great product.

To see a difference I would say any is a good pick but put a shower on if you don't have one. Showers will extend outdrive life more than anything else potentially could. "Underpropping a tad" will take a lot of load off the gears as well and if you can live with loosing 1-2 MPH then I would say do it. Extension boxes supposedly have a positive effect on drive longevity as well. Hitting the sticks hard takes it toll...put all this into place and the COMBINATION will improve your odds of having less probelms. Oh...keep the HP well within the limits of the drive...right

minxguy

Changing gear oils to a synthetic and picking up 1 MPH, Maybe in a small boat. Even a 22 footer needs about 20 HP to gain 1 MPH. Changing gear oils isn't going to "give back" 20 HP. Ken

jmherbert

I was thinking more along the lines of motor oil, but thus helps too

Hydrocruiser

Oh sorry...

Royall Purple Motor Oil are made of mostly Grade IV and Grade V synthetics. They do have a LOT of moly in them..."slick oils" ...

The hotrodders say you gain some HP form the reduced friction...then Teague says these type of synthetics cause flat-topping...

RP is a good product...it can behave wierd if gas gets in the oil Sterling says...

Redline has a ton of moly in it too.

Mobil-1 or Amsoil give me a better feeling. Better balance of additives in a strong base.

jmherbert

Can you queue me into what flat-topping is?

My main two concerns are:

1) protecting my flat tappet cam
2) water emusifying (protecting from internal corrosion/damage from moisture)

This is why I currently use Mercruiser oil. (and gearlube)

My boat will never see extended WOT runs of more than 5-10 minutes.

I could care less about a few lost or gain HP.

There is a well known auto racing speedshop (JR Motorsports) in my town, and they carry Royal Purple.

I know I apprieciate all this info, and I am sure others do to

Thanks

MOP

I see a lot throughout this post about various syn oils especially the HD 20/50 how many of you know there is something better! Even greater protection! I have been reading this post and more and am finally going over from Kendell GT1 20/50 to Spectro, check the link below and do your own research it may soon be the new up and comer.

http://www.spectro-oils.com/

Phil

minxguy

I have never heard the term "flat tapping". Are you refering to the flatting of the rollers in a roller type cam? If you are, you do not have that worry. You state that you have a flat tappet cam and this type of cam does not have any rollers in the lifter. As far as the water emulsifying question, are you currently experiencing water in your oil? The oil would look like gray floor paint if enough water was present. All oils will "hold" some water in suspension before it starts to effect the quality and color of the oil. Hopefully by running your engine and getting everything hot this small amount of water will evaporate. This is why auto makes say short trips are hard on oil. Condensation will build up in the oil will stay in the oil unless the oil gets hot enough to flash off. 150 degrees of oil temp will accomplish this. Obviously the hotter the oil the faster the flash or evaporation. Mercury has started to spec in their oil, both engine and gear, with an emulsifier. This additives purpose is to hold more water in the oil to give a longer service life. These emulsifers are very polar, with one part being water soluble and another portion being oil soluble. I personally don't care how much longer the oil life is with water in it, I don't want it in my engine.
All modern day engine oils, be it synthetic or petroleum have very strong anti-rust packages. If I was you, only running WOT for very shor times I would run Spectro 4 20w50. It is a petroleum lubricant for motorcycles that has been uptreated in the anti-wear package. A very shear stable product with excellent stay in grade properties. After all if you purchased and poured in a 20w50, would't you like to drain out a 20w50? I hope this helped. Ken

jmherbert

I personally believe that 'roller skating' with synthetics is a pure myth. If synthetics were so slick (which they are not) to cause the rollers not to roll, there wouldn't be any wear anyway because there would be no friction!

I have an old Harley, and I remember this myth was spoken like gospel by HD dealers about synthetics when they arrived on the scene. Nowadays the HD dealers are pushing it as the end all be all, now that HD has a synthetic line of their own. The fundamental innards (roller everything) of the HD motor have not changed since conception!

I'm no expert on the matter, but from what I have gathered the advantage of synthetics is that they are much more stable, especially under high temps, and the base stocks are more resistant to breaking down.

I had issues with water in the oil this year, looks like bad stock manifolds. This will always be a concern with me, since afterall the motor is a boat motor. I have ordered Revolution exhaust w/the dry flange, and my cam is not too large that reversion should be an issue. But the chances are always there for water to find its way to the crankcase, wether it be a little reversion now and then, or by condensation. IF it does find its way in there, I like to know that the oil somewhat accommodates for it, and the Mercruiser oil does.

minxguy

If you are worried about water in the oil, a real quick test is to drop a couple of drops of the suspect oil into a hot pan. if water is present in the sample, the oil will skate and dance in the hot pan. If the oil just thins out, no water is present. Ken