Oil Pressure Very High

[PBFITZ]

1995 Nautique Super Sport with 257 hours

On my initial start my oil pressure is VERY HIGH - 75lbs. and stays high for 10-15 minutes of running - no fluctuations based upon RPMs. After 10 -15 minutes the pressure drops to reasonable levels 40-60 based upon RPMs.

Oil is fresh SAE 40 and full. Checked pressure with analog gauge at the block - pressure is accurate. New Oil pressure sending unit.

Should I be worried about this or is this something relatively common?

[brkaus]

I'm interested as well. Mine does the same thing. ~180 hours.

[t.franscioni]

Does it go to 75psi upon start up even after the engine is fully warmed up prior to starting? If you drive the boat for 20-30 minutes shut it off and fire it up again does it go to 75psi? If not then it's probably just your oil being cold causing the higher pressure and as soon as it's gets to operating temp and thins out it flows easier through the engine and goes down to 45-60psi???

[BigBen_UK]

What oil filter are you using ? (I'm assuming it was changed at the same time as the oil) There's a pressure relief valve in the pump that will open around that 75 psi and I was wondering if you had a filter that was good but doesn't flow the 40 weight oil at cold that well. There's a study here with various flow rates http://www.offshoreonly.com/forums/g...r-study-2.html - I know it's for Chevy Mercruisers but you get the drift.

[PBFITZ]

I'm using Valvoline VR1 Racing Oil SAE 40 and a Motocraft FL-1A Filter. Yes the filter is always replaced with the oil.

This symptom only happens when cold. Once the engine starts reading 40-60 (presumably "warmed up") - it can be shut down and restarted without spiking the high pressure. But the next day (when Cold) same thing happens all over again.

I'm wondering if I should try a lighter weight oil..... or just not worry about it.

[t.franscioni]

Ya sounds like your oil is just needing to warm up. Try a multi weight oil like like Mobil 5-30 or something. That will give you best of both worlds cold flow and high ambient temp protection. Mobil synthetic comes highly recommended on these nautique for its flat tappet protection on the GT40s.

[BigBen_UK]

I think I'd be inclined to not worry about it and assume I have a nice tight engine, and only go higher up the rev range when warmed up to avoid undue stress on the pump drive/distributor gear.

[a0128]

. . . . Try a multi weight oil like like Mobil 5-30 or something. That will give you best of both worlds cold flow and high ambient temp protection. Mobil synthetic comes highly recommended on these nautique for its flat tappet protection on the GT40s.

COMPLETELY FALSE!

First Mobil 5W-30 does not have the correct zinc levels for a 1995 era motor. It only has 900ppm. An engine from the 1990's should get an oil with around 1400ppm of zinc. Secondly 5W-30 is way to thin given the range a marine engine operates in.
Nautique does not make oil recommendations, PCM does (even though PCM is owned by Nautique they are run by separate management and have different engineering personnel). PCM actually warns not to use synthetic oils in their current engine lineup.

I agree a multi-weight oil might be worth a try, however use the proper specification such as 20W-50. Valvoline VR-1 20W-50 is a good choice. I'd also suggest a new oil filter such as a Mobil1. See the filter chart below (courtesy of CCFan.com). The FL-1A was not highly rated (although many use it).

[jmo]

I would concur with running a multi-weight, 15w-40 would be my recommendation based on your locale. They will be labelled as "for diesel engines" but it will say in the fine print its fine for both diesel and conventional. Make sure you have a Ford GT40 block before going through the trouble of seeking out an oil with the proper zinc content as its harder to find.

Given you are in the Adirondacks - it will be cold in the mornings, especially if you ski in the Spring and Fall. I run late into November in MA, air & water temps in the low 50's, you definitely want a multi-grade oil for Northern conditions. Straight 40 weight is great if your in Texas or other really warm locales.

How is Lake Tupper by the way for skiing? I have looked houses for sale on Tupper and Upper Saranac, is there a slalom course on Tupper?

Good Luck.

[t.franscioni]

COMPLETELY FALSE!

First Mobil 5W-30 does not have the correct zinc levels for a 1995 era motor. It only has 900ppm. An engine from the 1990's should get an oil with around 1400ppm of zinc. Secondly 5W-30 is way to thin given the range a marine engine operates in.
Nautique does not make oil recommendations, PCM does (even though PCM is owned by Nautique they are run by separate management and have different engineering personnel). PCM actually warns not to use synthetic oils in their current engine lineup.

I agree a multi-weight oil might be worth a try, however use the proper specification such as 20W-50. Valvoline VR-1 20W-50 is a good choice. I'd also suggest a new oil filter such as a Mobil1. See the filter chart below (courtesy of CCFan.com). The FL-1A was not highly rated (although many use it).
[ATTACH=CONFIG]n495907[/ATTACH]

Completely Misconstrued

Never said to run Mobil 5-30 I said "LIKE Mobil 5-30 or something", as in it's an example of a multi weight oil. the correct weight range he chooses is dependent on his climate which I don't know enough about to make a specific multi weight recommendation. If he's skiing in a dry suit and its 40F and his boat is using 35F raw water as its cooling source then I would think 5-30 would be fine. Point to be made was to try a multi weight oil which I think we agree on.

I never said nautique makes oil recommendations or I least didn't mean to anyway. Insert "forums" after nautique. "These nautique forums" is what I meant but didn't think it was worth another post to correct that typo. Mobil 1 oil is one of the top 3 oils in zinc content I believe as per your CCF oil analysis thread your quoting from with filter recommendations? After all that CCF thread is why I'm choosing to run Mobil 1 in my GT40. Does it have 1400 ppm no but **** 900 is close enough for most people plus Mobil 1 is easily obtainable in almost any auto supply store. There are many oils to choose from if your in top 3 or 4 I would think that's a highly recommended oil? But maybe that would require defining "highly recommended".

Try the valvoline VR1 20-50 it should help lower your psi upon warm up as compared to straight 40W if that's what your trying to accomplish.

[BigBen_UK]

I'd not seen that thread on ccfan before - http://www.correctcraftfan.com/forum....asp?TID=31299 and I don't really want to start a "which oil filter is better" debate as they've been done to death, but it does make some interesting reading. Worth noting that the base data, for a GM 5.7L truck, does only take into account filtering @ 30µm and not flow rate - http://www.gmtruckcentral.com/articl...lterstudy.html

[PBFITZ]

Thanks for the advice from everyone.... I will experiment with different multi-weight oil and perhaps a different filter. If i get noticeable changes I will add a post.

Regarding Tupper Lake - there are plenty of good skiers on Tupper and Yes there is a terrific 6 buoy course. I'm a SkySkier....my days of rounding buoys is long gone! But it's still fun to watch folks tearing it up!

Thanks again!