What temps are you guys runnin

[1968Droptop]

I was reading Statue's post about his 460 and saw some chat about temps. What temps should I see ? I was told to keep the inlet valve (gate style) adjusted to keep the temps around 170 (ish). I was also told that you can have too much water pressure running through the engine. Is this right or wrong ? I've closed my inlet valve somewhat to bring my temp up. Now that I've read some of your posts, I'm thinking this may be incorrect ? I was corrected earlier about oil coolers (thought you wanted to warm up the oil), and now I'm wondering if I should just have my inlet valve WFO ?

[455Rocket]

I run mine at about 150 to 170 ... by adjusting the gate valve you were talking about. This is cool in relative terms, my truck runs at 180 to 210 for example
When I had my engine rebuilt the guy who did it told me about a test he did on the dyno w/ water temps (He raced a Eliminator Daytona) He said that (at the HP he was running) for every 10 degree difference there was a 10 HP gain... I don't remember the temp range though
I've heard about high H20 pressure problems but are unfamiliar w/ the issues it causes specifically.

[SmokinLowriderSS]

Well, first off, you do not wan tto overpressure your cooling system. A jet pump CAN put out over 300 PSI at full throttle. Never put anything restrictive in the water flow OUT of the system. Enough said there.
I'm running 170 deg at idle, even in the hottest part of summer, in 80+ degree water. Things may change this year as my cooling system route has changed due to the jacketed headers I am now running.
In my old system, Niccson log manifolds (exhaust), lake water ran thru the manifolds, both cooling them and pre-heating the water to the engine. That flowed to the front of my block, thru the engine, out the t-stat cover (no t-stat) and out the back of my exhausts to the lake. Engine idled fully hot 170 deg F, cruised on plane, pulled tubes, skii'd, ran WFO, 140 deg F maximum. Cold water in the spring would lower this about 10 to 15 degrees F. Ran this way since 1978, when new. The valve on mine is only aprox 2 turns from fully CLOSED with 5/8" lines upstream of the valve, all the same size.
You should get SOME heat in the motor, helps it run better, smoother idle, less wear on some moving parts, less thermal expansion/contraction under sudden loads. The trick is to NOT heat your fuel/air mixture charges any more than you absolutely have to. Warm engine, cold mixture charge, happy engine.
Oil temps are a completely different animal, and IMO have very little to do with engine coolant temperatures. Oil temps are much more regulated by stress on the oil from bearing loads (particularly from high rpm shear forces). An oil temp IMO should be tried to be kept below 250 deg F. Pure synthetics give some flexibility here on the temp tolerance, maybe to as high as 300 deg for short periods. Over 200 does help keep water (moisture) that has condensed inside the engine steamed out of the oil.

[n8dawg]

My boat when idleing for a period of time gets up to 150-160. Thats on a 90+ day at the river. When cruzing, temp drops to 120-130. I will tell you what happened to me one time. I had 4 adults, one dog, a 12x12 easy up, and a full huge ice chest in the boat. Driving up to big river from lost lake the temp started to climb past 200. My rookie ass opened the valve aaaalot. Oh yea the temp came down and when I got home and checked the oil it was a milky mess! Ended up blowing out the head gaskets, and the water pump cover gasket. On a good note, cleaned everything up and now it runs like a champ!
The valve is now opened about 3/4 of a turn, thanks to people on these forums.
Late,
Nate
my .02 :rolleyes:

[Not Twice]

Hey guys, not a professional here but there is a big difference between and closed cooling system pressurized (car or truck 180) and an open cooling system non-pressurized in a jet boat. First of all the in an open system the inlet water is probably 50 to 70 degrees when it enters the motor, and to have it measuring 160 to 180 when it exits the motor, that tells me that the motor is running way to hot. That water is only in there for a few seconds to get that hot. In a closed system all of the water stays relatively hot, the radiator does cool it off but the water reentering the motor is already hot. In addition a pressurized cooling system is just that, there is water everywhere in the motor, so you will not develop a hot spot or pocket of air. When you are running an open system, the water takes the path of less resistance and you may not be filling all of the spots of the motor and develop a air pocket. My water pressure gauge reads 5 to 7 lbs at idle and up to 20 lbs at wot. Water temp never seems to get over 150 even on hot days.

[xs ultra]

I'm running 454, water temp is always cold ,like 105 at the river.no valve in or out , and it was plump that way new.I would worry about air pocket also if the water was restricted coming in. Just my .02 .I had another boat which was plumb the same way and no problems.

[BigBlockBaja]

Im running about 175 to 200 through a thermostat kit. Works great.

[RCB19]

120-125* on the guage. But that is not necessarily the "True" temp of the engine but merely how much heat that the water has absorbed before it exits the engine. Run as much water as you can through the motor but controll the pressure with a regulator.

[1978 Rogers]

between 140 & 180. hotter when idling for a while.

[El Prosecutor]

I just rebuilt my pump and took it out for the first time this weekend - I was amazed at how little it took to keep the temp down in the 130-170 range. I have a gate valve setup that came with the boat, and it only has to be open about 3/4 of a turn. Any more than that and the temp doesn't even register on the guage, which goes down to 100. I have a mild 455 setup, and the boat has run on this cooling system apparently for years without busting gaskets. I guess if it aint broke. . .

[Squirtin Thunder]

I am very lucky to get around 140 cruising during the summer. On a long hard run I may see about 170 but that whould be a WOT pass of about 15miles or so. I am not controlling the inlet with a gate or ball valve but a by-pass with a gate valve, this way I only get about half the presure. I am also running 3/4" dump lines plus wet headers with lots of water.

[Devilman]

I was reading Statue's post about his 460 and saw some chat about temps. What temps should I see ? I was told to keep the inlet valve (gate style) adjusted to keep the temps around 170 (ish). I was also told that you can have too much water pressure running through the engine. Is this right or wrong ? I've closed my inlet valve somewhat to bring my temp up. Now that I've read some of your posts, I'm thinking this may be incorrect ? I was corrected earlier about oil coolers (thought you wanted to warm up the oil), and now I'm wondering if I should just have my inlet valve WFO ?
About 120-130, all the time with a 460 Ford. Idling, cruising, haulin ass, loaded boat, or empty boat, it don't matter. I have a ball valve on the line feeding the engine, prolly 3/4 of the way opened. Haven't had any problems with condensation or milky oil either. Some people say that its running too cool, but I figure, if it ain't broke don't fix it.

[Big Proppa]

my blown 468 never reaches 120 which is what my gauge starts at - I guess it runs about 110

[El Prosecutor]

Hey guys, not a professional here but there is a big difference between and closed cooling system pressurized (car or truck 180) and an open cooling system non-pressurized in a jet boat. First of all the in an open system the inlet water is probably 50 to 70 degrees when it enters the motor, and to have it measuring 160 to 180 when it exits the motor, that tells me that the motor is running way to hot. That water is only in there for a few seconds to get that hot. In a closed system all of the water stays relatively hot, the radiator does cool it off but the water reentering the motor is already hot. .
Yeahbut it doesn't matter why or how the water reaches that temperature, it only matters that there is a constant bath of sufficiently cool water to cool the engine :idea: . You are right that the engine temp is probably higher than the water temp, but in your hypo the engine is still constantly being cooled by water that is < 180 degrees.

[460 jus getn it]

my 460 runs at 150 at idle in the dead of summer, 110 crusing....

[centerhill condor]

I worried quite a bit about water temp.. the boat was from texas and only got warm when it was 90'f and 90%humid. also you read all the time about guys overheating the engine and not running warm enough for max efficiency or oil performance etc. so I searched and did the manual valve closing thing.. 3/4 open from fully closed did well. my concern was too hot at idle and not warm enough at cruising to wot and a wide temp rise between the two.
so, i bought the performance jet water bypass system to regulate the incoming water pressure to 14 psig and installed a 160 'f thermostat with two 3/16" holes drilled on either side of the thermostat valve. works great 160 at idle and 160 at wot and about 130-140 cruising with out the large temp swings and best of all I no longer watch the temp gauge with trepidation.
by a good set up and be done with it so that you can do what you purchased the boat to do; enjoy!
I've posted a link that goes into much greater detail and recommend the company for the product listed.
http://www.performancejet.com/techtalk.htm

[maxwedge]

Couldn't really tell you what temp the engine runs because some previous owner (idiot) installed my water temp sender so that it basically measures the temp of the water in the left side exhaust log. At least I know if the logs are running too hot. :D Guess I'll be fixing that too this winter.

[HammerDown]

I run the Rex T-Stat setup at 160 degrees +- . It's perfect, AND I also use Jer's one line in two out system...water pressure never goes below 8 lbs or above 12 lbs.
One should NEVER restrict water leaving the block!
PS I also pre filter water prior to entering the block or Header injection lines :rollside:

[396_WAYS_TO_SPIT]

Mine runs at 170@ idle in the summer and 120@wot.......

[Sleek-Jet]

Engine idled fully hot 170 deg F, cruised on plane, pulled tubes, skii'd, ran WFO, 140 deg F maximum. Cold water in the spring would lower this about 10 to 15 degrees F.
Oil temps are a completely different animal, and IMO have very little to do with engine coolant temperatures. Oil temps are much more regulated by stress on the oil from bearing loads (particularly from high rpm shear forces). An oil temp IMO should be tried to be kept below 250 deg F. Pure synthetics give some flexibility here on the temp tolerance, maybe to as high as 300 deg for short periods. Over 200 does help keep water (moisture) that has condensed inside the engine steamed out of the oil.
Ditto on the water temp.
As far as the oil temp... you want at least 220* and preferably a little more as a minimum running temparature, that way the moisture and contaminents are boiled out of the oil. I wouldn't shy away from 250* running mineral oil. I wouldn't even get to excited by 300*. Most oils are still doing their job at these temps. Now if you were seeing 325* or 350* or more, I would be looking at some way to cool the lubricant.
That begs another question, how many of us are running an oil temp guage??

[Devilman]

Ditto on the water temp.
As far as the oil temp... you want at least 220* and preferably a little more as a minimum running temparature, that way the moisture and contaminents are boiled out of the oil. I wouldn't shy away from 250* running mineral oil. I wouldn't even get to excited by 300*. Most oils are still doing their job at these temps. Now if you were seeing 325* or 350* or more, I would be looking at some way to cool the lubricant.
That begs another question, how many of us are running an oil temp guage??
Sine you are running one, where do you have it tied in to get the readings? I have been curious about that myself. Almost seems with an oil temp guage, wouldn't be much need for the water temp....

[Sleek-Jet]

I'm not running one either.... :D :rolleyes:
I've just found it odd that oil temp is probably more important, or at least as important, than water temp... and no one has the guage in the boat.
I've thought about installing one in the lower part of the pan (not really sure if that would work though)... if you had a remote oil filter, you could plump one in there. The rule of thumb is to add 20* temperature rise through the motor to the guage.

[Devilman]

I'm not running one either.... :D :rolleyes:
I've just found it odd that oil temp is probably more important, or at least as important, than water temp... and no one has the guage in the boat.
I've thought about installing one in the lower part of the pan (not really sure if that would work though)... if you had a remote oil filter, you could plump one in there. The rule of thumb is to add 20* temperature rise through the motor to the guage.
Oil temp has been brought up before, with quite a bit of debate if I'm not mistaken. It just makes me think that I may be able to have a better idea of whats going on with the engine, going off oil temp vs. water temp. My water temp gauge works, but the needle just lays there like a dead hobo, so whats the point of that?

[SmokinLowriderSS]

From what I have seen on other threads, oil temps will rise under heavy load (a WFO blast), often rise very high and very quickly. seems to depend a lot on engine power capability, RPM, oil flow volume, & oil capacity. I have never had an oil temp gauge, but will be installing one under the hood (next to the "back-up" mech oil press gauge), not in the dash. This way, I can find out what she does, and monitor it, but I do not feel the need to monitor it constantly. I am not running an 800 HP engine on a circle race but a 500 HP engine at play. 98% of Lowrider's running time is spent cruising or pulling people on the water. 2% may be outrunning someone. I am also only running a 5-qt pan. Since I have made a lot of changes in this old 454, I want to find out what the "new" status quo is and if it is acceptable or not.
IMO, for most of these engines, an OIL temp gauge is secondary to a block WATER temp gauge. For a much stronger, especially a solidly blown engine, I would give them both equal standing.

[Riverat84]

alright everyone. dont yell @ me....my valve is all the way open and i opened my breather to check the oil and there is a sort of foam in the bottom of my breather. should i change the oil and close my valve and mess w/ it while im floating in the river/lake? what am i doing wrong?

[SmokinLowriderSS]

Yer running an Olds, maybe Quaker State too? :argue: :p :D :D

[Devilman]

Yer running an Olds, maybe Quaker State too? :argue: :p :D :D
Pretty sure he's runnin a Ford..... :cool:

[Riverat84]

Pretty sure he's runnin a Ford..... :cool:
yeah i am running a ford....(if you guys are talking to me) i hope to god my cooling ducts inside the block arent ruptured or anything...i was thinking of changing the oil someday this week anyhow...

[SANGER-RICH]

I have been running my jet with a 468 for 15 years with the gate valve wide open, temp never gets up enough to barly move the gage, unless ideling for a long time, it runs great, I tried to control the temp by putting a gate valve on the outlet and was able to bring the temp up but blew freeze plugs, so I took the one on the out let off and just use the gate valve for shutting off the water when I leave her in the water all night :rollside:

[Riverat84]

so keeping the engine that cool isnt bad? my engine can barely idle by itself @ 900 rpm....you think i should close the valve a bit and run it warmer? will that thin out the oil a lil more and let it idle by itself? as far as the milky oil, will simply changing the oil fix the problem? thanx for errbody's time.

[RCB19]

so keeping the engine that cool isnt bad? my engine can barely idle by itself @ 900 rpm....you think i should close the valve a bit and run it warmer? will that thin out the oil a lil more and let it idle by itself? as far as the milky oil, will simply changing the oil fix the problem? thanx for errbody's time.
Running your motor on the cool side is not bad but running that valve wide open is bad. You need to controll the inlet pressure with a regulator or a pressure bypass valve. As far as your motor having a hard time idleing it is more than likely water running through your headers at idle. There should be no water entering your headers at idle. That needs to be controlled also.

[Devilman]

yeah i am running a ford....(if you guys are talking to me) i hope to god my cooling ducts inside the block arent ruptured or anything...i was thinking of changing the oil someday this week anyhow...
I wouldn't run that valve wide open. Just don't choke it down too much. How much is too much right?:D I just messed with the valve a bit while out on the water. Mine is a ball valve, about 3/4 open. I tried closing it a bit to bring the engine temp up a bit, next thing you know temp is sitting over 200 at idle. So I had to go back & open it back up a little. Like I mentioned before, my gauge starts at 130 & the needle barely moves if at all. Seems to be doing the trick, as the oil is clean & all that...

[centerhill condor]

man.. water in the oil makes me very nervous... 'cause you don't know if it is from a blown gasket or from too much water flow at idle through the headers.. :mad:
is the oil level a quart too high or do you just have some bubbles on the dipstick? if you have a quart of water in the oil, change oil and go from there. if it is just some bubbles run with it... I have.
I'd go ahead and do any feedwater flow adjustments with this watered down oil.. there's a chance you'll get the engine warm enough to boil off a small amount of water and if you do over heat the oil you were gonna change it anyway, right?
just don't run it soo hard until you have all this figured out. I have a previous post on this thread. I like an automatic water flow control system for a variety of reasons... fix it once and forget it!
good luck!

[centerhill condor]

btw.. nice boat!

[Devilman]

man.. water in the oil makes me very nervous... 'cause you don't know if it is from a blown gasket or from too much water flow at idle through the headers.. :mad:
is the oil level a quart too high or do you just have some bubbles on the dipstick? if you have a quart of water in the oil, change oil and go from there. if it is just some bubbles run with it... I have.
I'd go ahead and do any feedwater flow adjustments with this watered down oil.. there's a chance you'll get the engine warm enough to boil off a small amount of water and if you do over heat the oil you were gonna change it anyway, right?
just don't run it soo hard until you have all this figured out. I have a previous post on this thread. I like an automatic water flow control system for a variety of reasons... fix it once and forget it!
good luck!
Exactly... :cool:

[Riverat84]

Running your motor on the cool side is not bad but running that valve wide open is bad. You need to controll the inlet pressure with a regulator or a pressure bypass valve. As far as your motor having a hard time idleing it is more than likely water running through your headers at idle. There should be no water entering your headers at idle. That needs to be controlled also.
OH HELL NO i do not run watter through the headers at idle....im just thinking its something else...probably my HUGE cam haha

[Riverat84]

btw.. nice boat!
hey thanx man...i dont have a dipstick, just the breather w/ a few milky bubbles in it...actually like white oil in the bottom where it enters the valve cover. ill try getting the engine warmer to check it out...i dont even think i run my engine hard at all...i just love cruisin haha :rollside: