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TMX IO360

Flyguysr5

Active Member
TMX IO360 high oil pressure

New engine installed and have been backing out the oil relief valve to lower the oil pressure. Have backed it all the way out to the stop and it will still generate over the 95 PSI red line at run up until the oil temp hits 140 degrees. Still runs at 80 plus once at operating temp in cruise. Biggest issue is getting oil temp up for take off before cyl head temps get past 375 and then trying to keep them below 400 on climb out.... thoughts? Currently have 40 hours on the engine. I have confirmed pressure with a manual gauge ported in.
 
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paging Mahlon!
You might have to change the spring, but if Mahlon doesn't chime in, maybe James Ball at Titan can give guidance.
 
Springs

I looked in a lycoming parts manual, 5 different available springs. Wondering how this one made it thru run in at the factory.
 
...generate over the 95 PSI red line at run up until the oil temp hits 140 degrees. Still runs at 80 plus once at operating temp in cruise. ...

Looking at specifications for an IO390 from Lycoming and a Robinson R44 POH: both state the same upper limits of 115 psi during takeoff and 95 psi once warm which show your oil pressures are fine.
 

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spring or oil-cooler?

when i had my engine on the test-stand for first start-up, the guy at the controls shut it down after 3 seconds, said something like "....oil pressure to high...wrong spring...", changed the pre-load spring of the relief Valve and was happy after all.

So i think fl-mike hit it on the spot.

But Flyguysr5 Statement, why the factory did not notice, made me think as well.
It may also be the oil Filter having too much internal flow-resistance, causing the oil pump working against that?

If i remember correct, the oil goes from the pump into the oil-cooler. (if somebody can back-up this, please? i am not 100% sure, so please tell me i am wrong if i am)
If the oil cooler is providing too much of flow-resistance the pump will work against it until the spring will become the weakest Point (and opens up the bypass), causing high oil pressure.

Maybe the test facillity had a different oil cooler (with less flow-resistance)installed whilst doing the test-runs. That might be the answer why it passed there.

My own oil cooler wasn´t installed on my engine whilst on the Dyno at the engine-shop, but in my case it worked out anyways.

like said, i am no engine pro.....Maybe the experts can chime in on my proposal.
 
I just installed a Titan x340 and noticed high oil pressure. Mine has been running 93-97 psi or so. Figured I would run it for a while, possibly try a thinner oil as I have straight 50w in it now.
 
We normally set up oil pressure to yield 70-80 psi at temp in cruise. That is taking the oil pressure off one of the two1/8 pipe plug ports on the rear of the accessory housing designed for that purpose. The port just ahead of the oil filter on the right of the filter mounting boss typically yields about 5 psi more pressure then The one at the upper right corner of the accessory housing. Oil temps under 120F will yield high oil pressures at full power. Max is 115psi at take off not 95 psi. I don't have all your data but it would appear that you pressures that are near normal cold but slightly high in cruise. A lighter spring may be needed.
Here is some reference data for Lycoming oil pressure springs:
Highest tension to lowest yielding highest pressure to lowest are:
LW-18085 1.93 inches free length
LW-11716 2.12 "
61084 2.18 " (Most common spring)
68668 2.04 "
77467 1.90 "

Use the 61084 spring with an adjustable tower or a tall tower and a 68668 with a short tower to start. Use the 77467 in a short tower if you can't get the op low enough even without adjusting washers and using the spacer with two gaskets. That was the starting points and worked out really good 99% of the time. You should never need to use the top two springs in any normally aspirated engines. Normally you would have a 61084 in there. You are allowed to use any of the listed springs in any engine to attain pressure that are in limits and what you desire.
Hope this helps.
Good Luck,
Mahlon
 
TMX O-360 Info

My TMX O-360 engine has been running flawlessly since my first flight last March.
At the FAA getting my Repairman’s certificate yesterday I was asked were I could check for any AD’s or SB’s concerning my engine since it’s not a genuine Lycoming and Mattituck is no more. It was the only question they asked that I couldn’t honestly answer. :(
Has a Titan assumed responsibility for the TMX series ? :confused:
 
yes titan is now owned by CM which owned us. So they could support you. Contact Jim Ball. Tell him I said Hi.
You should treat you engine as if it were a Lycoming O or IO-360 when researching ad's. That should bring up all ads' for Lycoming, superior or eci parts and accessories that could be installed on the whole engines. Then you need to see which applied to your particular circumstance. ioe do you have cm or slick mags or what cylinders are installed etc.
Good Luck,
Mahlon
 
Thank you Mahlon. Nice to know your still out there watching over us Matttiuck
Orphans. Hope all is well. Take care of yourself Sir. :)
 
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