Black Baja

iTrader: (2)

Just an FYI. I've been running vr1 40wt in my motor all summer. Needed to do an oil change and got a heck of a deal from an OSO member on 20w50 Bradd Penn. I have a 16qt system so an oil change can be pricey that's why I bought the Bradd Penn. Went from 60 to 70psi at idle and 75 to 90 at WOT. Oil pan temp went from 250 WOT to 220. I wouldn't believe it unless I seen it with my own eyes. Deal or no deal I think I know what oil ill be using from now on. And the nice thing with the green oil is I can actually read the dipstick.

MILD THUNDER

iTrader: (3)

I think we are stroking ourselves until we get some true temp readings at wide open throttle. This is when his oil pressure issue happens. Temperature can have a direct impact on the oil pressure. Most BBC engines Ive seen, hold a pretty consistant oil pressure from 3000-6000RPM, when the temperature is steady. When my oil is 120*, and i get up on plane at 3000RPM, my oil pressure is in the 90's. Once it gets up to 190-200 degrees, its in the 70's at 3000 and 5500rpm. If you are getting say, 250* at wot, I can see it losing some oil pressure, compared to what it is at 185*.

The stock oil cooler is probably a 2x17 or 2x21 case. On a 700HP engine, I'd be running a 3x18 style cooler. A stock 2x17 cooler, is ok for a 400-500HP engine. At cruise speeds, you are well within the limits of the cooler, at wot, probably not so much.

Also, the stock fittings merc used on those cooler applications, suck as far as oil flow. The idea of an oil thermostat is to help maintain a steady oil temperature in all conditions. In our cars, we run say a 195* stat. We see 195* on our temp gauge. Now, remove the stock radiator on your tow rig, and install a radiator from a honda civic. I dont care what temp thermostat you install, its gonna exceed 195* temp.

Dean Ferry

Thanks guys for all the input. Here is my plan of attack:
1. I bought some Kendall (13 qts.) GT1 20-50 Wt oil and will use a Merc racing oil filter to change to after the Oil Thermostat change out.
2. I will go Mystic and pick up my new oil thremostat and sender for install this week
3. I confirmed with "Chris" Merc. Racing yesterday, (Nice guy by the way, we talked about 15 minutes about my oil issue) that I do in fact have a 12 Qt oil pan. There is a misprint in the Merc racing HP500 BD owners manual that I have that states its a 9 qt oil pan. I have attached a pic.of oil pan
4. I do have standard HP500 bulldog oil cooler that is 2x17"
5. I'm thinking about relocating my Oil temp sendor to the Oil pan, you can see in the pic of the 2nd boss available in the pan for that install. The other 1 is used for my oil drain hose.
6. Ensure that my Oil thremostat pad has a good ground.

ICDEDPPL

iTrader: (1)

Besides the oil gauge not working I don`t see any issues with the readings you posted.
Oil pressure is good.
Oil temp at 185* is fine
Drops when running hard= normal (oil heats up, gets thinner , oil pressure drops, mine drops to 50psi)
Drops after hard run @ idle =normal (mines drops to 20psi after a hard run with spring oilers)
Goes back up with some throttle= normal
You have 85* at the cooler.. unless the water you boat in is that temp looks like oil is running thru the cooler.

So besides the gauge I dont see what you`re worried about.

To test mine I take the sender out and drop it in some boiling water along with a thermometer and check against the gauge.( use an alligator clip to ground it)

racinfever

+++1

MILD THUNDER

iTrader: (3)

I think the concern is the fact the oil pressure is dropping while being at wide open throttle, along with unknown temps at wide open throttle. I agree 185 is just fine at cruise. Ive seen boats cruise with oil temps that were just fine. However at full kill almost bury the oil temp gauge at 300 degrees at full throttle thanks to a lean tune up and the pistons glowing red. Few seconds later a rod cap let go and put a rod thru the oil pan on this particular setup.

If im running along at 4000rpm with my oil temp gauge showing 190, and oil pressure at say 70psi, when i nail it to 5600rpm for a few miles, oil temp goes to 210, oil pressure stays at 70psi or better. I personally do not want to see my oil pressure drop when i advance the throttles to a higher rpm. A properly setup oil system should not lose pressure as rpm increases. Just my opinion. At 5500rpm, you should have the same, if not more pressure than you do at 4000rpm.

airjunky

iTrader: (2)

Pic was off but the orig 500 bulldog pan baffle set up was hard core . When merc charges 2k just for a cast pan I like to feel every inch nook and cranny . With the large lines right bypass valves in block orig cooler I've seen them support major boosted hp . Long shot and outside the box but maybe something in the cooler ? You running a sea strainer ? Those tall decks dont like dist seal issues down by the lifter galley area but yea be weary of foaming ,maybe run a t from your sender , and get ready for science .

ICDEDPPL

iTrader: (1)

Not every one has your machine work and assembly workmanship Mild Thunder!
Im still surprised your oil pressure don`t drop a bit as the oil gets hotter/thinnner.

MILD THUNDER

iTrader: (3)

I never said it didnt drop with temp. I said earlier in the thread my pressure cold is in 90s, and once up to temp in the 70s while running. Sure after a hard run and come to idle theyll be at 35ish in gear. What they dont do, is drop oil pressure when going from 4000 to 5500.

My operating range is 180-210 on my oil temps. Nothing fancy about my oil system. Stock chevy pumps that mike tkach shimmed for me, proper sized remote oil lines, no hokey restrictive fittings, merc racing thermostatic oil filter heads, canton oil pan with windage tray and trap doors, and a plate cooler.

Before mike and i redid the engines, and shimmed the pumps, i had about 50-60psi at cruise, with pressure dropping to 40-50psi at wot. It wasnt a temp issue, as my temps were good. Only think i can think of was it being all the restricive 90* fittings used in the remote system.

ICDEDPPL

iTrader: (1)

Don`t lie to me!!!