MILD THUNDER

iTrader: (3)

Id have to disagree. Oil Thermostats are affordable, and mine come into play every time my boat is used. Before I added them, the oil would NEVER heat up. Maybe im a bit slow, but the fix for that, in my opinion, wasn't adding a smaller oil cooler. So I added oil thermostats. Now, I get on plane, cruise at 3k for a little bit, and temps will rise to 180 and sit there. I could stand on the engines all day, and they never exceed 210, because my oil cooler is capable of keeping up. This is a Merc racing thermostat. I think the guys at Mercury knew a thing or two about oil temps. Theres a reason the element begins to open at 180, and is fully open at 210, and not set to open at 250*. The Keith Eickert, Canton, and several other thermostats are all within that operating range. None are setup open at 220-230+, because, they don't want the oil temp up there. Same reason mercury uses a water thermostat of 143* per say, because they don't want the water temp at 220.

IMO, there is absolutely nothing positive gained, by running oil temperatures of 250+ degrees, especially a non synthetic oil, in an endurance engine. Remember the old Castrol commercials about ''Thermal Breakdown'', there is such a thing.

lightning jet

I have oil thermostats on the cat and it runs at 210 to 230 unless I'm beating on it then I have seen 250 thats at 6300 130+ mph for a few miles ,back her down to 4000 and the oil goes right back in line I like to see at least 212 at some point that way you are sure there is no condensation left as water boils at 212.

The high oil temp happens in our drag boat when we pleasure boat with its 1000 hp blower jet boat that just doesn't have the water flow to keep up with oil,inercooler and motor its all fed of one # 10 line..........I know put a drag tube on it but that is DRAG lol

MILD THUNDER

iTrader: (3)

What kind of cooler are you running on the Cat?

lightning jet

3" x14" for the motors and 2x6 bundle on the trannys 632" tall deck darts five stage dry sumps 900hp spinning 132 gear dry six drives

mike tkach

iTrader: (3)

i have to agree with mild,if you are seeing oil temp above 235 either your cooler is not big enough or you are not flowing enough water through it.at 250 deg the oil is starting to break down,when that happens the oil looses it,s ability to properly lubricate,now the oil really gets hot from the xtra friction from poor lubrication.at this point even if you go to idle the oil has been comprimised and needs to be changed.we must remember that the oil also absorbes heat not just the water.the multi weight oils will break down sooner than straight weight oil because of the friction modifyers.

minxguy

Oil starts to oxidize as soon as you open the bottle and expose it to air. This is why manufactures also have a time element for oil changes.

If you don't believe this, pour oil into an open container and over time it will get darker.

The high temp to start worrying about oil is 300 F.

At this temp the oil start to oxidize at a much faster rate so it useful life is shortened. How much, that I can't tell you. But it won't be "dead" in 2 hours of use.The more you exceed 300 the oil life degrades almost exponentially

This will include synthetics, but the impact is less sever for synthetics because they can live at higher temps longer. But given the time, the end results will be the same.

Ken.

mike tkach

iTrader: (3)

if you see 300 deg you have a real problem,i would never run any engine until i see 300 deg,imo that would be crazy.

MILD THUNDER

iTrader: (3)

I agree. Synthetics do not suffer from breakdown like a dino oil. A 20w50 dino, is made from a base stock 20 weight. When the viscosity improvers break down, it will act like a straight 20. Plus synthetics do better with heat over a long period of time. We don't run our engines for 10 seconds down a track. If your oil is getting in the 220+ range for extended periods, Id rather have the synthetic in their.

I have been running 20W50 Valvoline Racing synthetic in my engines. I don't plan to switch back to dino oil anytime soon. Heres a quote from a redline oil guy

Some products are far more stable than others. You didn't list what actually viscosity that you are using, so its hard to tell what's going on. The fact that you are checking motor oil temp is the first battle, as relatively few teams are watching it closely.

Dry sump or wet sump?

We have customers that run the oils well above 280, but it's not something we recommend. You should be aiming to run around 220 to 230f. If you get toward 240 or 250, you look into how its being cooled. 260 or 270? You need to make some changes, in our eyes.

Again, I don't know what you're using, If you're going to look into Red Line, you should start with our 40WT Race. It's an ester-based 15W40 multigrade with lots of antiwear (ZDDP). Remember that going heavier isn't always best when trying to lower its temps, as a thicker fluid can trap heat.

Also considering a way to vent heat out from under the hood. That can make a dramatic drop in oil temp.

Hope that helps,
Cameron Evans
Red Line Oil

lightning jet

I like the quote MILD it looks familiar lol the kitty run's 220-230 at a cruise of 70mph to 90mph /3200 rpm to 4000 rpm we run brad penn in all are motors and found the oil temps went down with this oil and it contains all the GOOD nasty stuff that the big three are taking out oil (zinc and phosphorus) yes i'm running rollers but like to keep the little wheels rolling not sliding .......... ten pound's per thousand,this might be old school but it works for me and trust me we beet the tar out of every motor in the fleet

minxguy

I have personally seen oil temps peg a gauge the had a max temp of 345 F in a dwarf car running a Yamaha FJ1200 engine.

The engine layout was poor as very little air made it to the rear most cylinders.

Never had an engine problem as the oil was changed every practice/race.

It is all relative, oil will work at high temps, but depending on the oil, it won't work for long periods of time.

Don't forget, oil is tested at 100C for viscosity qualification.

Ken