Anonymous
01-17-2003, 01:32 AM
Have a PCM 351 on my recently purchased Shamrock 26 hard top. What is the recommended interval bewteen motor oil/filter changes? How about the transmission oil?
Date: 06:33 p.m. on 11-24-2000
Leprechaun
normal member in standard member. 2. Re:oil change
Every time I get into a boating Post Board discussion on oil and changes for these boats I catch $hit - but here's what I think and do anyway. First - throw out the manuals. They say change oil and filter every 100 hours. I say half that at least. Change it when you can no longer see the writing on the dipstick. On my rig that works out to around every 40 hours or so. No big deal - but now the controversial part - I only use 5 quarts 10W50 Castrol with a pint of STP. And a fresh filter every time. People just seem to freak whenever I suggest the heavy oil plus thickener. But this particular mix has alway worked fine for all the Shamrocks at my dock (Currently 5 boats) since 1979. And that '79, a 20' Pilothouse, has the original 302 in it - albeit with 2 valve jobs - it has gone, are you ready?, 14,ooo hours and still displays a steady 23kt cruise at 3000 and trolls down to 500 rpm all day long. Nobody, and I mean NOBODY, believes me when I tell them this - but the boat is right here at my dock and can be seen anytime. The secret is that the owner changes, and has always changed, the oil at 25 hour intervals - always 20W50 Castrol with a pint of STP. Plus he put in a Melling hi-volume pump, which he feels helps get the lube circulate better. Plus he's extra easy on his boats (He has 4 of various descriptions). I feel the heavy oil is necessary in a below-deck engine - its gets hot down there and anyway, if you've every pumped out you 10W40 oil after a hard run - you already know it comes out like water - no apparent viscosity there - try it with the 20W50/STP mix - still piss-water, but far, far better than that light stuff. Its all I use and recommend - try it and you'll see an immediate difference in oil pressure.
As far as trans oil changes - every season would be more than fine. Automotive Dexron III ATF for a Velvetdrive is what I use.
Regards, Leprechaun
Date: 08:51 p.m. on 11-24-2000
capnmel
normal member in standard member. 3. Re:oil change
Thanks Leprechaun. Your suggestions seem very real and reasonable to me. Your help and comments are appreciated.
Date: 09:40 a.m. on 11-25-2000
Irish Wake
4. Re:Re:oil change
Lep, Hello, With this oil recommendation, what oil pressure does your 351 run, both idle and cruising?
Regards
Randy
Date: 09:56 a.m. on 12-01-2000
Leprechaun
premium member in standard member. 5. Re:oil change
Randy - I have 850 hours on my original 351/250hp Ford/PCM so obviously some wear on the rotating assembly. I still get 65lbs pressure at cold warmup (1500rpm) and a steady 50lbs at 2900rpm cruise. Regards, Leprechaun
Date: 06:33 p.m. on 11-24-2000
Leprechaun
normal member in standard member. 2. Re:oil change
Every time I get into a boating Post Board discussion on oil and changes for these boats I catch $hit - but here's what I think and do anyway. First - throw out the manuals. They say change oil and filter every 100 hours. I say half that at least. Change it when you can no longer see the writing on the dipstick. On my rig that works out to around every 40 hours or so. No big deal - but now the controversial part - I only use 5 quarts 10W50 Castrol with a pint of STP. And a fresh filter every time. People just seem to freak whenever I suggest the heavy oil plus thickener. But this particular mix has alway worked fine for all the Shamrocks at my dock (Currently 5 boats) since 1979. And that '79, a 20' Pilothouse, has the original 302 in it - albeit with 2 valve jobs - it has gone, are you ready?, 14,ooo hours and still displays a steady 23kt cruise at 3000 and trolls down to 500 rpm all day long. Nobody, and I mean NOBODY, believes me when I tell them this - but the boat is right here at my dock and can be seen anytime. The secret is that the owner changes, and has always changed, the oil at 25 hour intervals - always 20W50 Castrol with a pint of STP. Plus he put in a Melling hi-volume pump, which he feels helps get the lube circulate better. Plus he's extra easy on his boats (He has 4 of various descriptions). I feel the heavy oil is necessary in a below-deck engine - its gets hot down there and anyway, if you've every pumped out you 10W40 oil after a hard run - you already know it comes out like water - no apparent viscosity there - try it with the 20W50/STP mix - still piss-water, but far, far better than that light stuff. Its all I use and recommend - try it and you'll see an immediate difference in oil pressure.
As far as trans oil changes - every season would be more than fine. Automotive Dexron III ATF for a Velvetdrive is what I use.
Regards, Leprechaun
Date: 08:51 p.m. on 11-24-2000
capnmel
normal member in standard member. 3. Re:oil change
Thanks Leprechaun. Your suggestions seem very real and reasonable to me. Your help and comments are appreciated.
Date: 09:40 a.m. on 11-25-2000
Irish Wake
4. Re:Re:oil change
Lep, Hello, With this oil recommendation, what oil pressure does your 351 run, both idle and cruising?
Regards
Randy
Date: 09:56 a.m. on 12-01-2000
Leprechaun
premium member in standard member. 5. Re:oil change
Randy - I have 850 hours on my original 351/250hp Ford/PCM so obviously some wear on the rotating assembly. I still get 65lbs pressure at cold warmup (1500rpm) and a steady 50lbs at 2900rpm cruise. Regards, Leprechaun