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  #1  
Old 07-24-2011, 04:39 PM
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lostpilot28 lostpilot28 is offline
 
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Default High Oil Temps - Vernatherm question - opinions, please!

I'm still trying to get my oil temps a bit lower, and so I took the advice of another builder and checked out my oil-temp sender then my Vernatherm. The oil temp sender (reading from my MGL EFIS) was within 1 degree of my digital meat thermometer, so I'm good to go with that.

The Vernatherm is a different story, though. When I took it out, I looked inside the oil filter adapter and noted that the gasket seems to be interfering with the Vernatherm seating in the oil hole. See the first picture below. In the first 2 pictures, you can see the edge of the gasket is actually "dimpled" around the edges from where the Vernatherm contacted it. I'm guessing that the upper 1/3rd of the hole didn't seal, and this could be my problem.

The 2nd picture is what I did to try and correct this with the new gasket, and the 3rd picture is with everything put back together. Note that there is a lot more clearance around the hole in the last picture.

I have 3 questions from this whole experience, and I would greatly appreciate any help.
1 - Is it OK to trim the gasket like I did? Has anyone ever seen the oil adapter gasket block the hole like that?
2 - I couldn't find in my engine manual a torque value for the Vernatherm. Does anyone know what it is?
3 - My Vernatherm had a flat aluminum (?) washer under the head. No copper gasket. Is that OK? Is it OK to reuse it?

Thanks in advance!





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Last edited by lostpilot28 : 07-24-2011 at 04:49 PM.
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  #2  
Old 07-24-2011, 06:31 PM
rwhittier rwhittier is offline
 
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Default 300 inch pounds

According to my Superior manual.
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  #3  
Old 07-24-2011, 07:37 PM
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rocketbob rocketbob is offline
 
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The right-angle oil filter adapters are bad designs, and this points out well why that's the case. On a normal oil filter housing there is a chamfer that the vernatherm face seals against. In the case of the right-angle filters, it uses the hole the oil comes in thru on the accessory case and as you can see it can never seal well against a sharp edge, let alone one that has a piece of gasket covering it. Yes you should cut away the gasket but I would expect even with it cut away the seal is marginal at best.
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  #4  
Old 07-24-2011, 08:39 PM
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Bill.Peyton Bill.Peyton is offline
 
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I know you must already know this, but the Vernatherm must seat tightly for the oil to flow through the oil cooler. Also, take a look at the Vern. itself and make sure that the camfer is smooth and also check the seat for same. You can also check the Vernatherm by heating it in oil to 185 deg. and verifying that it extends fully, which is .160 inch minimum. As Bob said, the right angle adapter is a poor design. I would cut the gasket so as not to let it interfere with the vernatherm extending into it's seat.
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  #5  
Old 07-24-2011, 09:27 PM
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lostpilot28 lostpilot28 is offline
 
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Thanks guys. By the look of the Vernatherm's contact point, it looked like it had wear marks all the way around. I believe the hole that it fits in did have a slight beveled edge. I was just really surprised that the gasket was blocking the Vernatherm from making a full seat.

As noted, the bottom picture is with the gasket trimmed back to allow the Vernatherm to fully seat. I hope this works in bringing my temps down.

I'm wondering if the other guys with ECI kit engines have the same problem. It certainly looks to be a design issue, and I read about a lot of ECI's having high oil temps. I actually bought 2 louvers to put on the bottom of my cowl, but I'd really prefer not to cut holes in it if I didn't have to!
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Old 07-24-2011, 10:36 PM
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az_gila az_gila is offline
 
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Question

Quote:
Originally Posted by rocketbob View Post
The right-angle oil filter adapters are bad designs, and this points out well why that's the case. On a normal oil filter housing there is a chamfer that the vernatherm face seals against. In the case of the right-angle filters, it uses the hole the oil comes in thru on the accessory case and as you can see it can never seal well against a sharp edge, let alone one that has a piece of gasket covering it. Yes you should cut away the gasket but I would expect even with it cut away the seal is marginal at best.
But isn't the hole in the accessory case the same one that is used for those Lycomings that came with an oil screen rather than an oil filter?

The hole should be suitable for a vernatherm according to Lycoming.

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  #7  
Old 07-25-2011, 05:47 AM
mahlon_r mahlon_r is offline
 
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1 - Is it OK to trim the gasket like I did? Has anyone ever seen the oil adapter gasket block the hole like that? Yes absolutely, Yes all the time if the gasket is used without trimming.
2 - I couldn't find in my engine manual a torque value for the Vernatherm. Does anyone know what it is? 300 inch pounds
3 - My Vernatherm had a flat aluminum (?) washer under the head. No copper gasket. Is that OK? Is it OK to reuse it?
Only use the aluminum and I think you will be OK with a reuse one time.

I doubt if trimming the gasket will make much difference with the oil temp....

Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."
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  #8  
Old 07-25-2011, 07:47 AM
fstringham7a fstringham7a is offline
 
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Default RE: Different Path

Hi Sonny

In my thread with a similar problem I left you hanging.

http://www.vansairforce.com/communit...w+oil+pressure

Like you I have been dealing with the high oil temp but also marginally low
(55 in cruise) oil pressure. Mahlon has given great advice, ECi folks have chimined in, America's Engine ... who built my enigine .... have also given advice, and finally the local A&P has been a help.

The advice has been all over the map. Vernatherm, oil pressure regulator, blocked oil cooler, bad baffling (I have a Robbie Attaway style lid not rubber againts the cowl for my air recovery), and so it goes.

Unlike you I started with the oil pressure regulator. Installed a new heavier spring and guessed at the proper screw setting. No joy on my last flight. Higher oil temps, and as Mahlon suggested very high oil pressure on take off. But the oil pressure in cruise was higher in the mid 60's. But......

On close inspection of the engine compartment during the oil change, oil pressure regulator spring change I noted a line of oil streams heading up the back of the fire wall from the bottom flange. They went up about 3 inches.....sorry know pictures I just cleaned it off with out making the connection that oil dropletts should be going down not up. So maybe my Vetterman four pipe exhaust is restricting air flow thus causing a high pressure area thus ......you get the idea.

So I will be doing some surgery on my cowl to increase the area of the outlet. I am going to calculate the area differential between the inlet and outlet. (I guess it is supossed to be 1 to 1.75)

I also plan on doing the vernatherm check as you are doing to prove / disprove it's function. I read in a Lycoming circular that an easy check is to get the engine above 180 and check the oil cooler lines to see if they are as hot as the oil sump and to also check the oil cooler to see if it it also hot or has cool spot ( indication of air blockage in the cooler).

My plan is to unscrew the pressure regulator screw at least three turns. Go fly and check results. But, if Mahlon is correct temps will probably remain high with the pressure going down down down..... On the other hand maybe ECi and America's Engine folks will be right and I will hit the sweet spot for oil pressure regulation and oil Temp.

Then I will do surgery on the cowl if necessary.

Then the vernatherm...................So I will follow your thread closely to see how your plan works out and to see if you can overcome what some say is the bad design in the oil filter adapter. I have the same setup so maybe that is why I choose the easy route of the oil pressure regulator and hope that it is the culprit.

At the end of the line one of us is going to have joy when we solve this situation.

I have really enjoy all the threads on this issue and especially engine gurus like Mahlon who are willing in give we mere mortals free advice.

PS:Mahlon ....when do you sleep ...... 4:47 AM is pretty early to respond but thanks a bunch or your help!!!!!!!

Frank @ 1L8 ... Fly and Tracken with MT_RTG

Last edited by fstringham7a : 07-25-2011 at 07:53 AM.
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  #9  
Old 07-25-2011, 07:51 AM
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rocketbob rocketbob is offline
 
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Quote:
Originally Posted by az_gila View Post
But isn't the hole in the accessory case the same one that is used for those Lycomings that came with an oil screen rather than an oil filter?

The hole should be suitable for a vernatherm according to Lycoming.
True, and that makes two poor designs...

On my rocket I have removed the expensive vernatherm and put the oil cooler bypass plunger and spring, and will control the oil temps manually with a ball valve.
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Last edited by rocketbob : 07-25-2011 at 07:54 AM.
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  #10  
Old 07-25-2011, 08:02 AM
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lostpilot28 lostpilot28 is offline
 
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Quote:
Originally Posted by fstringham7a View Post
...
Unlike you I started with the oil pressure regulator. Installed a new heavier spring and guessed at the proper screw setting. No joy on my last flight. Higher oil temps, and as Mahlon suggested very high oil pressure on take off. But the oil pressure in cruise was higher in the mid 60's. But......
...
My plan is to unscrew the pressure regulator screw at least three turns. Go fly and check results. But, if Mahlon is correct temps will probably remain high with the pressure going down down down..... On the other hand maybe ECi and America's Engine folks will be right and I will hit the sweet spot for oil pressure regulation and oil Temp.
Hey Frank, quick question...I meant to ask this before, but if the minimum oil pressure (by the book) is 25 psi, why are you worried about it "only" being 50 psi in flight? I'd start worrying if it were closer to 25 in cruise, but 50 sounds good to me. What am I missing?
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