HELP with enigine temp!!!!

[Budman13]

I have a 2006 21 ft. lightining with a 502 chevy marin power engine with 500 hp. The hottest i have seen the temp guage is about 110. I believe it should run about 170 to 190, is this right? Does this cuase any powerloss or damage. The boat is factory set no changes. Should this be corrected if so how?

[BrendellaJet]

Lots of jets run that way. What are you running for exhaust? Do you know what your water pressure(in the block) is at now? More than likely you could turn down the water pressure from the jet and increase temps. How does it measure if you've been on it hard for a few minutes? Idling?

[Squirtcha?]

Don't sweat it. Lots of em have run that way for years.........mine included.

[Budman13]

The temp basically stays the same no matter what. It never goes above 110. I have ran the boat for two seasons and have never seen it above that. I'm trying to get all the performance out of the motor I can so I was wondering if the temp would help. I have lightning through tansom headers on the engine. I don't know the water pressure from the pump or through the block or how to adjust that. Help in that area could be useful. Thanks for any info.

[cyclone]

The temp basically stays the same no matter what. It never goes above 110. I have ran the boat for two seasons and have never seen it above that. I'm trying to get all the performance out of the motor I can so I was wondering if the temp would help. I have lightning through tansom headers on the engine. I don't know the water pressure from the pump or through the block or how to adjust that. Help in that area could be useful. Thanks for any info.
Running the engine at a hotter temp will not increase performance.

[1968Droptop]

Is 110* the lowest your gauge reads ? If so then it might not even be that warm. Some peeps like 'em ice cold, some like 'em a little warmer. Personal preference, nothing more.

[Squirtcha?]

The temp basically stays the same no matter what. It never goes above 110. I have ran the boat for two seasons and have never seen it above that.
If you idle for a while it should come up to about 140-150 degrees. You might want to check your wiring and/or gauge and sender to make sure its working right.
Still..........Provided you don't have any problems with water in your oil I really wouldn't worry about it. It'll be less prone to detonation at the cooler temp. That's at least part of the reason these guys are able to run their big pony motors on pump gas.

[4trax]

I had the same ?'s about my engine and here is what the engine builder ( Bob Kamp Owner of K-Motion racing ) replied with.
Water should be warmed to 140 degrees.
180 to 200 degrees wide open.
Bob Kamp
4trax wrote:
I was just wondering when you built this engine. Did you know it
was going to be used in a jetboat? If so what temperature did you
assume the boat engine would be running? Cause the way this guy had
it plumbed in is the water was not being preheated. I was told that
this is hard on engines because of thermal shock so I'm plumbing it so
the water gets preheated before entering the block. Was just wondering
if this would be ok or better for the engine or was it built to run
cold like 100' to 110' degrees. I was told it would better to get it up to
atleast 140' to 160. Idling around and 180' at wide open throttle.
So there you have it from a engine builder.

[Boostedballs]

don't overlook the fact that some marine gauges and atomotive gauges use different resistance ranges. I tried a GM sender on my olds 455 and it said I was around 110deg. Then I changed to a marine sender and my temps showed 180deg. So I hooked up my thermocouple lead to the thermostat housing and it read almost dead nuts 180deg.
I think the senders for boats are 140-240ohms, or something like that. The easiest way to check, of course, is the palm method. If you can hold your hand on it, it's probably less than 160deg.

[Squirtcha?]

I had the same ?'s about my engine and here is what the engine builder ( Bob Kamp Owner of K-Motion racing ) replied with.
Water should be warmed to 140 degrees.
180 to 200 degrees wide open.
Bob Kamp
4trax wrote:
I was just wondering when you built this engine. Did you know it
was going to be used in a jetboat? If so what temperature did you
assume the boat engine would be running? Cause the way this guy had
it plumbed in is the water was not being preheated. I was told that
this is hard on engines because of thermal shock so I'm plumbing it so
the water gets preheated before entering the block. Was just wondering
if this would be ok or better for the engine or was it built to run
cold like 100' to 110' degrees. I was told it would better to get it up to
atleast 140' to 160. Idling around and 180' at wide open throttle.
So there you have it from a engine builder.
Something doesn't seem right about that statement. Your water temps are going to go down at WOT rather than up. You're running more water through the block due to the increased pressure/volume from the pump and it'll be cooler unless you're running a bypass valve or thermostat setup.
Also if they're susceptible to "thermal shock" why am I still running the original motor (1976) without any problems whatsoever? I'm not pre-heating the water and I don't use a thermostat, or even a bypass valve and mine's doing just fine. The motor has only been rebuilt one time and it was because I wanted more power, not because anything failed from "thermal shock" or any other reason. I can about guarantee that had I not done the rebuild it would still be running.
No matter who says what...........I won't be changing around my cooling setup. If it ain't broke..............
Heck the OEM setup for boats with headers is the most basic you can get, and there are lots and lots of em out there built in the 70's still running around the lakes and rivers like that.
Do a search. This is by far one of the most discussed jetboat topics (also a pet peeve of mine). It's been done to death.