IO-360 High Oil Temp Culprit

While training for TD endorsement I was seeing up to 238 deg oil temps in climbs so I elected to cancel training until this was under control. The horrible listener I am, I decided to read the oil temp issues here on VAF which most discussed baffling and a variety of other issues as well as vernatherms.
Knowing this has been an issue with the previous owner I decided to look deeper.
Pulled Vernatherm and marking on the male seat were not seating 360 degrees, only about 3/4 of the male plunger seat had any indication of touching the 45 degree female beveled seat while extended in the spacer block.
I pulled oil filter adaptor and spacer block and bolted them together as you would mount it to the back of the case. With the oil filter removed I heated the housing to 200 deg and poured water into the hole which just ran right through.
I do not understand why there is no dowel pins for this critical assembly alignment ??
With the Vernatherm still extended fully, I loosened the bolts to where I could just wiggle the adaptor and let the spring pressure of the Vernatherm on the male seat find the 45 degree bevel and life was good and it held water.
I think this is a poor design and has caused grief for many, I know at least for me that I have ordered a larger cooler which has required me to learn sheet metal skills, found I need different tools $, new Vernatherm$, new hoses to fit bigger cooler $$, EZ COOL $, baffle material$
Sure wish I would have found the issue earlier in the game.

...or you learned a new skill and improved your critical thinking and problem solving skills

Welcome to aircraft ownership, here's your bill.

Mine too

On the way to Triple Tree last Saturday, my oil was at 202 F by the half way point and I'd never seen oil that high, except for when I was running WOT during a race.

When I reduced power, it went higher still, to 214 F at 100 MPH, the speed they wanted me at. I babied it home at 60% power and it turned out to be a defective vernatherm with 700 total hours on the engine.

Best,

Picture worth 1000 words.....

This is the issue Stan describes above. Clearing some motor mounts requires the addition of a spacer block to move the B&C oil filter adapter rearward. The spacer block and the adapter have clearance diameter in the holes for the mounting bolts/studs, thus the block and adapter can "float" in relation to each other as the bolts/nuts are tightened. If spacer and adapter body are not perfectly aligned, the tip of the vernatherm won't be centered on the oil passage in the spacer block, thus the vernatherm cone can't seat in the passage when hot and extended. As a result, oil flow can bypass the cooler, even at elevated temperatures.

If I recall correctly, an ECI right angle adapter is similar. Are adapter and spacer doweled for alignment, or free to move like the B&C?

No Vernatherm?

What would be the pros and cons of removing the "Vernatherm" altogether?

Bad Sheila said:

What would be the pros and cons of removing the "Vernatherm" altogether?

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Might as well toss the oil cooler at that point. The Vern closes the bypass port and forces the hot oil to the cooler. I think your idea would be to plug the vern port closed permanently. All the oil would be forced thru the cooler at all times, not a good result.

DanH said:

Picture worth 1000 words.....

This is the issue Stan describes above. Clearing some motor mounts requires the addition of a spacer block to move the B&C oil filter adapter rearward. The spacer block and the adapter have clearance diameter in the holes for the mounting bolts/studs, thus the block and adapter can "float" in relation to each other as the bolts/nuts are tightened. If spacer and adapter body are not perfectly aligned, the tip of the vernatherm won't be centered on the oil passage in the spacer block, thus the vernatherm cone can't seat in the passage when hot and extended. As a result, oil flow can bypass the cooler, even at elevated temperatures.

If I recall correctly, an ECI right angle adapter is similar. Are adapter and spacer doweled for alignment, or free to move like the B&C?

Click to expand...

I'll answer that now - they are not doweled, I have the ECI and pulled my vernatherm today (still chasing that last 15 degrees cooler oil that I want) and sure enough I only have about 210 degrees of contact mark on the 360 degree face of the vernatherm tip. I just got done raping the backside of the engine to get to it, then stopped to pull up my laptop and re-read this thread before reassembling.

The worst part of the whole deal was I pulled my oil filter (punched a hole in it to drain it first), and now I realize I'm out of new oil filters, so I can't even take it on a test flight today after I get it all back together...

airguy said:

The worst part of the whole deal was I pulled my oil filter (punched a hole in it to drain it first), and now I realize I'm out of new oil filters, so I can't even take it on a test flight today after I get it all back together...

Click to expand...

I use a Napa Gold 1515 filter and have had no problems or issues. Locally available for $5

Larry

I am about to pull my Vernatherm to check for miss-alignment as I have the ECI 90 degree adapter with about a 2"-2.5" spacer. Is there a good way to align the parts while tightnening? Oh and I have a new filter.

lr172 said:

I use a Napa Gold 1515 filter and have had no problems or issues. Locally available for $5

Click to expand...

...or about half that during the semi annual oil filter sale most stores have.

I buy them by the case (I use the NAPA 1068's).

MarkW said:

I am about to pull my Vernatherm to check for miss-alignment as I have the ECI 90 degree adapter with about a 2"-2.5" spacer. Is there a good way to align the parts while tightnening? Oh and I have a new filter.

Click to expand...

Well I'm not sure I have a GOOD method, since I haven't been able to test it yet... but what I did was put the adapter in place and the bolts were just shy of finger tight, maybe 1/4 turn off of finger tight, so I could wiggle the adapter around by hand. I dropped the vernatherm into a coffee cup of boiling water, then ran it into the ECI adapter and could feel it bottom out. I wrenched it in a turn tighter and wiggled the adapter around to bottom out the vernatherm under spring pressure before it cooled and contracted, then quickly tightened down the adapter and torqued/safetied everything. We'll see if that does the trick.

The biggest hassle of the deal was having to pull my standby alternator and EI to get access to the adapter.