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nzjetboating.com Forums => Tech Library => Topic started by: JohnR on October 20, 2016, 15:04:29 PM

Title: Lexus oil temp
Post by: JohnR on October 20, 2016, 15:04:29 PM
Hey guys. My lexus is running arround 120 -130 degrees C oil temp at wot. Is this okay and is my setup plummed properly. Has brand new 82 degree thermostat with the jibbler still in. Thanks in advance
Title: Re: Lexus oil temp
Post by: Matthewf/Norbert/TuiDog on October 20, 2016, 15:11:41 PM
sounds about right with no oil cooler  b>
Title: Re: Lexus oil temp
Post by: Hacky on October 22, 2016, 20:48:11 PM
I once experimented with different oils and which gave me a varied oil temperature range. The oil I ended up with seemed to top at 130 deg with no oil cooler. other oils just kept getting hotter. They were all well respected oils in there day. I now only use a quality synthetic oil which handles heat a bit better than mineral oil.. At 150 deg I would use an oil cooler but don't then run the oil too cool.  B))T B))T B))T
Title: Re: Lexus oil temp
Post by: Brebner on October 22, 2016, 21:30:04 PM
Your mixer is not right water go's in the thermostat and out where your mixer mounted the thermostat opens to let cold water in to the engine
Title: Re: Lexus oil temp
Post by: Ross Goldsack - JBNZ Immediate Past President on October 22, 2016, 21:38:10 PM
Your cooling system has very little effect on oil temp. Without an oil cooler my Chev will run at a water temp of 80c and oil temp can get up to 140c.
Title: Re: Lexus oil temp
Post by: JohnR on October 22, 2016, 21:56:10 PM
Lazybone should i hook a water temp guage up and biff the oil temp guage away so i cannot see it and problem fixed )1
Title: Re: Lexus oil temp
Post by: Ross Goldsack - JBNZ Immediate Past President on October 22, 2016, 22:03:59 PM
Quote
Lazybone should i hook a water temp guage up and biff the oil temp guage away so i cannot see it and problem fixed )1
l-l water temp gauge are good.
Quote
do you rekon a lower thermostat will not help?
Nar it won't change a thing. The rule of thumb is optimum max oil temp is about 20 - 30 degrees above water temp. ie water temp @ 85 oil at 110.
Different oils will run at different temps......so I'm told. And sometimes dropping a couple of hundred RPM will let the oil temp come down a bit.
Title: Re: Lexus oil temp
Post by: Ross Goldsack - JBNZ Immediate Past President on October 22, 2016, 22:21:38 PM
oil at 140 while only pulling 3800 RPM does sound very hot! Can you borrow another gauge to check? Just to make sure you do have a oil temp problem.
It is measuring in Celsius Eh?
Title: Re: Lexus oil temp
Post by: JohnR on October 22, 2016, 22:24:01 PM
Yup its defiantly in celcius and ive used a infared lazer to confirm. Itl go to150 degrees at 4000rpm after a while.
Title: Re: Lexus oil temp
Post by: Hacky on October 22, 2016, 22:50:05 PM
I think most people don't realise how hot there oil gets in a boat as they mostly don't have an oil temp gauge. Engines seem to survive fairly well in spite of the oil temp. In cars the air flow past the sump is greatly responsible for maintaining a reasonable oil temp, which isn't there in boats. The question is....... to install a cooler and make sure the engine has the best possible chance of survival under extreme conditions, or..... no cooler and take the chance that it will be ok like most do and they seem to survive any way.  The million dollar question.
Title: Re: Lexus oil temp
Post by: Brebner on October 22, 2016, 23:02:58 PM
On later engines the thermostat opens to let cold water in and not hot water out like in the Hamilton manual run a 15mm s/s pipe in a u in your sump as an oil cooler plumb to with the heater hoses were on your Lexus
 
Title: Re: Lexus oil temp
Post by: Matthewf/Norbert/TuiDog on October 23, 2016, 00:44:47 AM
now you are saying 150c! thats a lot more than 120-130!
most modern cars, petrol and diesel will run oil at about 120-130 when working hardish


using a IR Laser gun is inaccurate! p>  they are hopeless and could be giving big errors.

Title: Re: Lexus oil temp
Post by: Ross Goldsack - JBNZ Immediate Past President on October 23, 2016, 08:29:31 AM
now you are saying 150c! thats a lot more than 120-130!
most modern cars, petrol and diesel will run oil at about 120-130 when working hardish


I agree with Matthew. Modern cars run water temps of 90 - 100 degrees C, + 20 - 30 for the oil.
My  2c is in a boat with raw water cooling aim for water at 85 and oil at a MAXIMUM of 125 degrees C, that's foot flat working hard out, at cruise  the water temp should remain static and oil temp drop back to 100 ish.     
Title: Re: Lexus oil temp
Post by: JohnR on October 23, 2016, 08:32:52 AM
My guage is brand new and sender came with guage. Its teed in at the oil filter with the pressure sensor. I played with the temp guage and infared gun on the oil filter over a range of different degrees with the gun pointed at the oil filter and degres was within 5degrees of the guage. Should i take it for a run with the thermostat out. And how come using a lower temp thermostat wont change anything. Is it do do with flow and not temp?
Title: Re: Lexus oil temp
Post by: JohnR on October 23, 2016, 09:22:22 AM
Is this the correct thermostat for a lexus also.
Title: Re: Lexus oil temp
Post by: Brebner on October 23, 2016, 18:10:17 PM
Yes it is move your cold water pipe to the bend that go's to the thermostat housing then that thermostat will act as your mixer and let cold water in when needed and you may need to move your outlets to the same side to get the manifold temperature the same
Title: Re: Lexus oil temp
Post by: JohnR on October 23, 2016, 18:43:01 PM
Done. And fixed. Temp stable between 100 and 125 max. Cheers guys. Much appreciated. Eapecially brebner
Title: Re: Lexus oil temp
Post by: Brebner on October 23, 2016, 18:54:58 PM
Spot on happy to help now you can go back to enjoying boating
Title: Re: Lexus oil temp
Post by: bbs 540 on November 24, 2016, 20:12:11 PM
I was always told oil is 20% of an engines cooling. I like to keep oil between 95-105 celcius. anything over that for any length of time cooks your oil and its additives that keep it stable, so after 20 or so hours its good for bugger all. Easiest way I think is to increase the capacity of your sump. One extra litre of capacity makes a big difference to oils temp without the extra hidden problems of oil coolers, associated fittings, "o" rings, remote oil filters and the like failing. But if you spend most of your time at cruise oil temp won't be a problem, it is only the last 10% that makes everything hot.
Title: Re: Lexus oil temp
Post by: daveb on November 25, 2016, 16:00:17 PM
My old man ran the pipe thru the sump in the early 60s, a lees marine ,papakura, auckland thing and he was a waimak boater in the ol J30 with the hamiltons, mannerings,p philips, j heslop and g davison..quite simply he said it slugded up the sump with thick sh.t..not effecient cooling...then savage came along with proper oil coolers and they don't fail ! go to savage manufacturing..do it once do it right *-)
Title: Re: Lexus oil temp
Post by: JohnR on November 26, 2016, 07:28:09 AM
Ur old man would of been running cold raw water thru his sump. Im running it off the heater hoses so its arround 80 degrees. So it wont get sludged up. I did this because it says to in the hamilton 212 manual.
Title: Re: Lexus oil temp
Post by: daveb on November 26, 2016, 07:44:18 AM
Correct
Title: Re: Lexus oil temp
Post by: Gunnadoo on November 26, 2016, 23:40:41 PM
Hey John have you considered installing a bilge blower? I run same motor as you, on a three stage. I installed one during build initially for safety (get rid of any fuel vapour if around) but I think helps with drawing hot air out(great for warming trigger finger beside outlet in winter when reached destination ;-). I have inlet pipe for mine down low at back of sump, draws air past sump from up front via under floor. I don't have oil temp gauge but.
Title: Re: Lexus oil temp
Post by: Hacky on November 27, 2016, 10:48:09 AM
Hey John have you considered installing a bilge blower? I run same motor as you, on a three stage. I installed one during build initially for safety (get rid of any fuel vapour if around) but I think helps with drawing hot air out(great for warming trigger finger beside outlet in winter when reached destination ;-). I have inlet pipe for mine down low at back of sump, draws air past sump from up front via under floor. I don't have oil temp gauge but.

A carbi would be drawing much more air than an average bilge blower would draw, and they still wouldn't compare to the air flow of a car at 60 kph

The correct way ( but more expensive ) is a thermostatically controlled oil cooler so oil gets hot quick but then maintains the correct temperature.

 B))T B))T B))T