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High oil temp on break-in

lella

Member
Hello fellow RV pilots,

I just had my IO 360 rebuilt following a prop strike and now during the break-in I'm noting higher than normal oil temps. CHT's and EGT's are fine, but the oil temp at cruise, full rich stays around 215 degrees. I've only had three hour on the engine since the Lycon rebuild and I'm using Aero Shell 50 Mineral Oil for the first 25 or so hours. This engine never ran hot before the re-build.

Can anyone out there give me some advice?
 
What break in procedure does Lycon recommend? Call them if you have any questions.

215f does not seem unreasonable to me for break in.
 
Not uncommon

I saw the same thing on my engine, some say its due to the absence of carbon on the piston tops. Makes sense to me, and after about 8-10 hours it dropped like 20 degrees on my engine, which is exactly what I was told would happen. If your worried cut the filter open and have a look. You should do that anyway after the first few hours. The filter will have a lot more dirt and particles in it even after only 2-3 hours than you would normaly see, but should be relatively clean.
Tim
 
its normal

My first 10 hours was the same 215 check my baffles and found some air leak in the side and the temp drop to 200, then when the engine break in the temp goes to 190.




I saw the same thing on my engine, some say its due to the absence of carbon on the piston tops. Makes sense to me, and after about 8-10 hours it dropped like 20 degrees on my engine, which is exactly what I was told would happen. If your worried cut the filter open and have a look. You should do that anyway after the first few hours. The filter will have a lot more dirt and particles in it even after only 2-3 hours than you would normaly see, but should be relatively clean.
Tim
 
heat

I agree with David...............keep it above 2400 RPM and don't worry too much about it until your oil temperature reaches 230 degrees. The lubricating ability of the oil deminishes at about 245 to 250 degrees. 230 degrees is a safe margin, but run it as hard as you can to keep it below 230 degrees. You won't be sorry.
 
What break in procedure does Lycon recommend? Call them if you have any questions.

215f does not seem unreasonable to me for break in.

I'm following the Lycoming Break-In procedure to the letter.
These temps are a tad bit too high for ambient winter temps around 40 degrees.
Something is wrong, and I must trouble shoot it until I find the problem...
Thanks for the advice...
 
Thanks guys for all the responses on my "high oil temp problem". You've all been inspirational during the last couple sleepless nights.
What I've concluded from this discussion, is not to worry too much unless the oil temp exceeds 230. Secondly, continue running it hard throughout the break-in with the hope that it will come down naturally...

I'm still not convinced it's operating right and I'm going to check three things...

1) Confirm oil Temp Gauge accuracy
2) Confirm vernatherm is working and
3) Confirm there's no blockage in the oil cooler hoses

This engine always ran exceptionally cool, even during hot summer temps.
Now, in cool ambient temperatures, the oil temps are excessive (215/220) at 4000 ft. cruise,
24 mp 2500 rpm, full rich... In fact after landing, during taxi, it shot up to 225 and I shut the engine down and had to manually tow pull my poor 4 back to the hangar by hand...this after hearing a "knocking" sound from the engine...

I've checked the baffling and it's fine, sealed well. Air flow to the cooler is good and the hoses are all tight (I will check for blockage though).

Could it be that I have a bad batch of 50 weight mineral oil? Does mineral oil cool less than Ashless Dispersant?
 
Check your grounds

Calibrating the OT is a good idea, do the CHT's while your at it, but it sounds like the consensus is your numbers are not out of line for a new engine. There's no point in doing any other trouble shooting until you know the gauge is accurate and you have 10 or so hours on it.
You might want to check your grounds if you find it out of calibration, small errors can make a significant change on a sender and if a ground was put in a new location or was not connected properly when the engine was reinstalled it could cause a bad reading.
Cut the filter open also. If you have experience looking at filter elements in the past just know a fresh engine will show more dirt than normal and some fine ring and cylinder grindings, so it will look worse than normal after the first 5-10 hours, but should still be pretty clean, no or few big flakes. If in doubt show it to someone, but I think you will sleep better after seeing what's in the filter.
Tim
 
water boils at 212

Remember that the water boils at 212 ?F so if you have that temperature all the water or condensation that can reach your engine boils and corrotion goes out so its important to know that lowers temps are not always a engine saver.





Calibrating the OT is a good idea, do the CHT's while your at it, but it sounds like the consensus is your numbers are not out of line for a new engine. There's no point in doing any other trouble shooting until you know the gauge is accurate and you have 10 or so hours on it.
You might want to check your grounds if you find it out of calibration, small errors can make a significant change on a sender and if a ground was put in a new location or was not connected properly when the engine was reinstalled it could cause a bad reading.
Cut the filter open also. If you have experience looking at filter elements in the past just know a fresh engine will show more dirt than normal and some fine ring and cylinder grindings, so it will look worse than normal after the first 5-10 hours, but should still be pretty clean, no or few big flakes. If in doubt show it to someone, but I think you will sleep better after seeing what's in the filter.
Tim
 
heat

Lella,

Do your due diligence and put your mind at ease. I certainly don't blame you. Your high oil temperature is a very common thing for a new engine. Keep it below 230 and fly the puddin' out of it. I'm sure in the very near future the temperature will drop all at once and your oil consumption will drop as well. At that point, your rings will be seated and you can enjoy the airplane for another 2000 hours. Good luck.
 
Also, don't be in a big hurry to switch from the mineral oil. Keep running it till you know it is broken in....
 
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