If the thermostat inside the oil-cooler fails, does it go to full open?

[ao.frog]

Thanks for the replies guys. I've learned alot today!

Guess I'll make a mess if I take that valve out without draining the oil, so I guess that draining schould be done first.

Then measuring the length both when I get it out and then in boiling water. Great idea!

Gotta love this forum....

[DanH]

Alf,
My own adventures in vernatherm checking here:

http://www.vansairforce.com/communit...9&postcount=12

I doubt it can fail in the extended position, but hey, can't hurt to check.

More about the oil circuit here:

http://www.vansairforce.com/communit...ight=schematic

I know that SOMETHING has changed since last winter, because back then I had no problems keeping the oil temps up....

Just for fun I'll throw in two "normal" possibilities. One is that you had a baffle seal leak, and it molded itself into compliance during the summer. Increased upper cowl pressure would result in more mass flow through the cooler. The other is reduced combustion gas blow-by due to improved ring seating. Blow-by is a big factor in oil temperature.

Do you mind if I copy it for my Pilot Manual?

Thanks for asking Bob. Yes, you may....I drew it for the public domain.

[sgjackson]

Good information so far. My little suggestion would be to verify that your fasteners are all still tight. The Van's adjustable vents I am familiar with are adjusted by Push-Pull cable and I am wondering if the connection has loosened to allow it to slip and the vents to not close. It may even function correctly while on the ground because it does not have the air pressure behind it, but if it is loose then once you are in the air and it has the air pressure on it then the connection may be slipping and not closing.

Good luck.
jackson

[Bavafa]

While we are on the subject of oil cooling, I just removed my aft closing shutter and installed Vans shutter in the front. I am just hoping that it is not too restrictive in a fully open position and will get adequate cooling in the summer time. With a aft closing shutter, I flew all summer long with no heating issue.

[ao.frog]

Hi guys.

This is a follow-up to my previous post:

During last winter, I had low oiltemps (130-160*F) basically all the time. They varied some due to powersettings and OAT's, but it was not possible to get them above 180*F at all until OAT's increased this spring.
I had the Vans Oil cooler shutter fully closed all the time.

I'm just done with annual, and I took the oppurtunity to remove the Vernatherm, examined it and measured it in room-temps and in boiling water.


Here's a pic in room temp. Total length 95 mm (approx 3 and 3/4 inch)






And here's how it looked after a few mins in boiling water. Total length 102 mm (approx 4 inches 1/32)





I also removed the Vernatherm from the Lyc IO-360 I'm building right now (the other one is from my flying -7) to have something to compare with, and they behaved more or less exactly the same way those two Vernatherms.

Here's a pic where one is cold (the short one) and one has just been removed form boiling water (the extended one)





Here's the back side of them both:





So there you have it folks: what schould I do as the next step?
BTW: I have checked the oil-temp gauge and sender and they seem perfectly fine to me, both regarding what they show and how they look and behave during flight.

There must be SOMETHING that prevents the oiltemps from getting up to the normal temp-range.
Any suggestions?

Thanks

[Gary 40274]

Where are your CHT's. If they too are low you can cut down on the inlet air. I live in Minnesota and it is common in the winter to block off part of the inlets with duct tape. Sometimes as much as half is blocked.

The other thing is to make your engine produce more heat by increasing your power setting. When it gets cold your engine struggles to get warm enough to boil off moisture from the oil.

The ironic thing is I am writing this and it is 99 degrees F out. Good luck

Gary Specketer

[ao.frog]

Thanks for chiming in Gary.

The CHT's has mostly beetween 275 and 375*F (aproximate) depending of OAT's and powersetting.
During high powersettings (takeoff and acro) during summer, the CHT's have been at 400*F +/-

The thing is that the CHT's and oiltemps have been like this since break-in in 2008 and up until last Fall. Then SOMETHING must have happened resulting in lower oil-temps.

I wish I knew where to look next.... so I can find the reason why the oiltemps has become so low all of a sudden....

Any ideas anyone?

[larrynew]

Originally Posted by ao.frog

Any ideas anyone?

Bad temp sender or gauge?