View Full Version : Mercury Tech 200EFI operating temp?
While idling up no wake areas this summer at around 1000 RPM's , water temp upper 70's, is close to 180 degrees temp on the gauge sound normal. If I back off a bit it will drop. What should the temps be at under various idle and speeds? Thanks for listening, Craig :D:thumbsup:
olmo40
09-26-2009, 06:07 PM
Around 140 is normal ,180 is getting towards hot.
Can you hold your hand under the tell tale ?
Are the connections on your guage tight ?
How long since you changes impeller and checked cooling system?
Is your over heat alarm hooked up also check sensor on the motor .
Remember not all guages read the same ,
Around 140 is normal ,180 is getting towards hot.
Can you hold your hand under the tell tale ?
Are the connections on your guage tight ?
How long since you changes impeller and checked cooling system?
Is your over heat alarm hooked up also check sensor on the motor .
Remember not all guages read the same ,
Next time out and it reads over 140 while idling at a grand I will get up and reach back to feel the tell tale water. I have read somewhere that you could actually catch some of the water there and check with a good thermometer such as a kitchen one. Is that true? This is on a new boat with my engine from the old boat and it read this way then also. Last year I had a bunch of mods done (200HP drop on powerhead, reeds, etc.) and I always have the water impeller changed each season. I hope the marina that did all the mods hooked up the overheat alarm. How can I test for that? I had a bunch of stuff removed like the 2 small black boxes and the oil pump. I have read where guys check the poppet for obstructions. How do you do that? How do ya check the thermostats. Where is the sensor on the motor you referred to? Sorry for all the questions, I am trying to learn all this stuff myself so that I can troubleshoot without having to always rely on the marina. Thanks a bunch, Craig :thumbsup:
mach351
09-27-2009, 07:26 AM
You may have the wrong temp sender for your guage. I went through this years ago when I had bought new merc guages and hooked my temp to the stock sending unit in the head - it however needed to be hooked the small brass screw in sensor common in hp applications. It would show just like your saying - HOT - but really wasn't.
Look up your guage and see what sender is required.
tlwjkw
09-27-2009, 07:38 AM
I hope the marina that did all the mods hooked up the overheat alarm. How can I test for that? :
Sensor is located on starboard head right below no. 1 spark plug. Has a single tan wire. Follow tha tan wire to tha term block where it connects to tha tan wire coming outta tha harness. Don't take loose. Take a jumper wire and GROUND tha terminations. That should give ya a warning buzzer at tha console.........t
TEXAS20225
09-27-2009, 07:51 AM
you got pistons for the Bridgeport we win Second yesterday C U later:cheers:
You may have the wrong temp sender for your guage. I went through this years ago when I had bought new merc guages and hooked my temp to the stock sending unit in the head - it however needed to be hooked the small brass screw in sensor common in hp applications. It would show just like your saying - HOT - but really wasn't.
Look up your guage and see what sender is required.
I hear ya....the gauge is a Beede and it came in the Allison. thing is, this was happening in the old boat as well. Except the old gauge was not as detailed as this one. I was beginning to get concerned then as well. I will check the back of the gauge again though. Thanks
Sensor is located on starboard head right below no. 1 spark plug. Has a single tan wire. Follow the tan wire to tha term block where it connects to tha tan wire coming outta tha harness. Don't take loose. Take a jumper wire and GROUND tha terminations. That should give ya a warning buzzer at tha console.........t
I'll try that....obviously with the key switch on, right? So just take a wire with a small alligator clip on each end and attach one end to the terminal you mentioned and the other end to the block somewhere? Sorry for the dumb questions. Where can I get a good manual for my Merc. It started as a 1991 XR4 but now has a rebuilt 1997 200HP powerhead. I need to start learning some of these things myself. With a good manual and you guys I should be able to figure some things out myself. thanks for your help!! :thumbsup:
Oh, how abut WOT temps? Are they only determined by lake water and air temp? What's normal. I noticed inthe spring when the air was cold and the water temp around upper 40's that the needle stayed low on the gauge. This summer at WOT it read around the 150 mark.
tlwjkw
09-27-2009, 09:15 AM
Yep and yep. Temps will vary form motor ta motor. T-stats should open around 143 degrees. Tha temp guage you have more than likely reads a metal temp at tha head, just like tha warning sensor. You need ta have a temp set up that reads actual water temp ta get it down ta the real reading. As long as tha buzzer (if its workin') isn't going off you are probably safe.
Buy a manual (real mercury) for tha 200. Maybe a Merc dealer can order ya one or try ebay..................t
"temp around upper 40's that the needle stayed low on the gauge. This summer at WOT it read around the 150 mark."
Normal and just fine........
Jay Smith
09-27-2009, 09:19 AM
Mach351 is correct make sure your sender is a match to the gauge and ALSO with a temp gun make sure your getting the proper information ... I always check gauge for suspect bad information via a temp gauge before getting aroused...
Jay
i agree, I carry an infrared temp gun in my tool bag. THey sell them at napa and sears amongst other places. good investment, it gives pinpoint readings where ever you aim it.
Yep and yep. Temps will vary form motor ta motor. T-stats should open around 143 degrees. Tha temp guage you have more than likely reads a metal temp at tha head, just like tha warning sensor. You need ta have a temp set up that reads actual water temp ta get it down ta the real reading. As long as tha buzzer (if its workin') isn't going off you are probably safe.
Buy a manual (real mercury) for tha 200. Maybe a Merc dealer can order ya one or try ebay..................t
"temp around upper 40's that the needle stayed low on the gauge. This summer at WOT it read around the 150 mark."
Normal and just fine........
Well, I just checked the overheat buzzer with the jumper wire and it went off. So I know that is working. I may just have my thermostats changed out for a set of new ones. I don't know if the t-stats in there now that came with the powerhead were new or not. Once replaced, can I dunk the old ones in hot water with a good thermometer and monitor the temp of the water and see when and if they open? How do ya get a temp set up that reads actual water temp? Thanks again, I'm learning. Craig :thumbsup:
Mach351 is correct make sure your sender is a match to the gauge and ALSO with a temp gun make sure your getting the proper information ... I always check gauge for suspect bad information via a temp gauge before getting aroused...
Jay
Thanks Jay, I am sure that the sender in the engine is from the Teleflex gauge. The indash gauge that came with the boat is Beede. I will have to check the Beede website and see if there is a compatibility thing or not. As a matter of fact, the gauge originally in the boat when I picked it up was a Faria and when we stopped by the Allison's plant on the way home Mrs Allison gave me a Beede gauge to match the rest.
I'll do as fish suggested and get a temp gun from NAPA. That way I'll know for sure. :thumbsup:
i agree, I carry an infrared temp gun in my tool bag. THey sell them at napa and sears amongst other places. good investment, it gives pinpoint readings where ever you aim it.
Good advice fish....Aiming the gun at the area close to the sensor on the head should give a reading then comparable to the reading at the gauge at the time. Right? Thanks for the help and advice. Craig :thumbsup:
mach351
09-27-2009, 05:36 PM
Yeah, the heat gun is a good idea. That's how I got mine figured out - sitting there idling at the dock the guage showed 150, aimed the gun at it and it said 96! Got the right sender and all is well.
I called Beede instruments today and talked to a guy in Tech. Very friendly and helpful. He stated that the teleflex sending unit will be compatible if the teleflex gauge was one that went form 100 to 240 in temp. Now I gatta call the dealership where I traded in my boat and ask them to look at my gauge to see if it goes to 240. LOL I can't remember??!! Anyway, the tech said that a sending unit from an auto parts store will work and he gave me a bunch of parts numbers for various manufacturers. How bout that! :thumbsup:
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