Oil Pressure Vs. Oil Flow

[Kostarika]

Hello Scud,

 

I went the mechanical route with the pressure gauge.

The gauge gets the pressure reading from the oil route to the heads.

I had to source a double banjo and hooked up the oil line from there.

http://www.v11lemans.com/forums/index.php?showtopic=18435&hl=kostarika&do=findComment&comment=196469

you can see the set up in this topic.

I chose the location of the gauge on the in the fairing because the previous owner had installed a switch there.  

 

On start up i get anywhere from 5-30 psi

then on idle 100 rpms around 20 psi

around 3000 rpms around 60

then above 3000 rpms anywhere between 60 - 80 psi

 

I chose the mechanical way because I wanted a second system to the electronic one.

Plus if I could everything would be mechanical.

 

Hope this helps.

[Scud]

Thanks for the info. My oil pressure sender is where the stock unit used to be. I assume pressure should be about the same between the two points. Your start up is similar to what I see, and your peak pressures are a bit higher than I get at first.

 

You don't see pressure drop when it warms up?

 

What weight oil are you using - and is it organic, or synthetic?

[Lucky Phil]

I would be checking the relief valve for leakage if i were you. The pressure you are seeing isnt OMG dangerous but its at the bottom end of the comfort zone.

 

Ciao 

[GuzziMoto]

I don't know if your pressures are OK, but I do know that it is normal for pressure to go down as the oil warms up. And switching to a heavier oil (like from 10/40 to 20/50) will increase the oil pressure seen at the gauge. Some 20/50 oils are thicker than other 20/50 oils as well. Oil weights are like tire widths, they are more of a general idea than an exact measurement. They are not regulated by anyone, they are self regulated using the honor system.

Low oil pressure can be from a weak/worn pump or a tired motor with large clearances.

[Scud]

Thanks for all the info and advice. 

 

I'm going to ride it a bit more and rip into it soon. Headed out for a week tomorrow with the family (and the LeMans and Husqvarna in tow). The Husky is going to see the most duty next week - probably just a few short, scenic jaunts on the LeMans, with a careful eye on my lovely new oil pressure gauge... 

 

Given that I don't know the history of the bike, but the odometer was broken, maybe it has more miles than I thought... or maybe one of the POs ran it low on oil once... or...?

 

At a minimum, I'll try a WIX filter and 20w-50 oil.

 

Meanwhile, if anybody is aware of a particularly useful thread that shows how to test the oil pressure relief valve or the bearing or other clearances, please feel free to post links here. 

[gstallons]

The way to "test" the relief valve or bearing clearances is with disassembly.

[JRD]

Scud- I am no expert by any stretch but those really sound like low pressure readings. I was also told "10 lbs. psi per 1,000 RPM".   Its ironic that you are posting this as there is a similar thread on one of the British bike forums regarding low oil pressure after warm up.  Several experienced members suggested checking the oil pressure relief valve and also the lower end bearings.  One other point to consider, how accurate is the oil pressure gauge you installed?  Good luck and keep us posted.

 

 

 

Jerry

[docc]

At a minimum, I'll try a WIX filter and 20w-50 oil.

 

Looking forward to seeing if this makes some real difference. Something like Lucas 20w-50 V-twin oil?

 

(I'd be edgy about pressures under 20 psi, but that's just me. Being edgy. )

 

What's the stock idiot light threshold again? (I forget)

[Scud]

The way to "test" the relief valve or bearing clearances is with disassembly.

 

I figured as much for the relief valve.  But as for checking main and piston bearings - the crankshaft has to come out? That'll be a new adventure for me...

 

One other point to consider, how accurate is the oil pressure gauge you installed?  

 

I paid extra to upgrade to the more accurate one and match my other Speedhut gauges. I called Speedhut to double check - they claim zero problems with this gauge. If I had it to do over, I would get a mechanical oil pressure gauge, even if it didn't look exactly the same.

 

Looking forward to seeing if this makes some real difference. Something like Lucas 20w-50 V-twin oil?

 

 

(I'd be edgy about pressures under 20 psi, but that's just me. Being edgy. )

 

What's the stock idiot light threshold again? (I forget)

 

 

Well, at least I have data to compare against. I was thinking the Maxima 20w-50 synthetic, same as I have in the Scura. Is there something special about the Lucas product?

 

I think some people said the warning light comes on in the low single digits - like 4-5 PSI.

 

Here's the thing about this whole topic - without the gauge I would never have suspected an issue or known any of this. Not to cause great anxiety in others, but... without a gauge all you know is:  "Oil Pressure > 4PSI when the light is off."

 

Anyway  - I'll see all you boys in a week to ten days. I'll try not to stuff the Husqvarna into any lava tubes or gold mines.

[Kostarika]

 

 

What weight oil are you using - and is it organic, or synthetic?

 

Royal Purple Max-Cycle 20-50 synthetic

[Scud]

Update - the LeMans performed well on my recent trip to the Eastern Sierras, mostly short rides (+/- 100 miles) in the mornings. One morning, with temperatures near freezing, I saw about 80psi at startup.

 

I just pulled the sump and found:

• No debris
• No metal on the magnetic drain plug
• Clean screen
• UNI filter was secure and only had one gasket (still in perfect condition)
• Mating surface for gasket has no scratches

I filled it with fresh 20w-50 Maxima full synthetic oil, along with a new WIX filter. Initially, I was encouraged, because the pressures in the first couple miles were much higher than I saw with the 10w-40. Example: 70psi at 4,000 with the 20w-50 vs. 40psi at 4,000 with the 10w-40.

 

Then, when it was fully warmed up, I got about the same pressure readings as posted earlier (post #6). Example, just below 20psi at 4,000.  The easy checks and switching to heavier oil have not made a difference.

 

Stay tuned for an independent oil pressure gauge and/or further disassembly... 

[GuzziMoto]

I can't see taking a motor apart if it runs fine just because you get oil pressure readings like that. I am pretty sure the Guzzi motor is a plain bearing motor. Plain bearings do not rely on high oil pressure to work, they rely on oil flow. They need oil to work but they do not need high oil pressure to work.

Do you know anyone else local to you with a V11? You could mount your oil pressure rig on theirs and see what pressures you get, but even if yours is lower I can't see taking it apart if it runs well. Look at the moving parts that you can see without taking it apart. Do they show signs of heavy wear?

[Scud]

As good fortune would have it, there is another V11 close by, right in my garage.  My Scura has only 7,000 miles on it; I can compare against the LeMans (and it's unknown past). After yesterday's oil change on the LeMans, they both have the same Maxima 20w-50 oil.  I just ordered an oil pressure test kit - will hook it up to each bike for comparison.

 

As to wear, I did notice a worn part when I retorqued the heads. There is a pair of brass (I think) washers that go near the springs on the rocker arm pins. They had some grooves in them, but not having spares on hand, I reinstalled them. I assumed the LeMans had fairly low-miles when I bought it, but seeing those grooves gave me some cause for doubt. 

[Scud]

Update - I managed to get a mechanical oil pressure gauge connected today (test kit). I got the same readings as posted before, which just confirms the accuracy of the gauge I installed.  So there's one more thing off the list...  and I got a new tool, so that's always a good day.

 

 

Good looking mount, dontcha think? 

 

Meanwhile, I've been riding it almost every day - mostly my short commute - and it's doing fine. 

[docc]

Looks like something Carroll Shelby would have had the boys do on a Cobra at Sebring . . .