water temp gauge

[canman]

hi everyone . i am going to buy a water temp gauge for my 1990 140 horse johnson . what i need to is where the sensor goes . i know where the gauge goes , but not to sure where to install the sensor . thanks .

 

[wavrider]

Re: water temp gauge

the ones I have seen installed have been on the #1 cylinder. starboard head seems to run warmer than the port.

Pay close attention to detail on the measurent/clearance reccomended from the manufacture as this will provide accurate readings.

 

[Silvertip]

Re: water temp gauge

There are several types of sensors and before you buy the gauge, make darn sure you know what you are buying. Outboards run much cooler than I/Os which are auto engines so the gauges and senders are different. A temp gauge intended for I/O's is generally calibrated 120 - 250 degrees give or take a little on the high end. If you attempted to use that gauge on an outboard the needle would hardly ever get off the 120 peg. What has happened is that temp gauges from teleflex for example have a dial calibrated C-N-H (cold, normal, hot) which is really useful (might as well have an idiot light). There are a few gauges calibrated 60 - 220 which are ideal. You have to look around but they are still available. So whatever gauge you buy, you need a sender to match. Now to your question.

There are also a couple different senders. One type is mounted on the cylinder head of the engine with the bracket held in place by one of the head bolts. The other type screws into an unused port that places it in contact with the water in the water jacket. Other than what I've explained, its a matter of following the directions.

 

[ezeke]

Re: water temp gauge

The loopers like yours have tapped blind holes already prepared on the cylinder heads for you to place the sender in. Just be sure to provide thermal compound for good heat transfer and good electrical ground. In other words, don't use pipe compound or tape.

 

[Silvertip]

Re: water temp gauge

This is what it looks like on my Merc.

 

[emdsapmgr]

Re: water temp gauge

My 91 60 hp Johnson had a factory tapped, flat-bottomed hole in the head, designed for an aftermarket temp sender. Teleflex makes a number of senders, including the one I bought. It looked a lot like the Merc one in the pic above. Is only 3/4" of 1" high and maybe 3/8" around. Small. Flat on the tip. When screwed into the hole, the sender tip bottoms on the flat part of the hole. Nice. Be sure the gauge matches the sender, and Silvertips comment on the temg gauge ranges is worth noting. Check Teleflex's website.

 

[Silvertip]

Re: water temp gauge

And those look like this:

 

[ezeke]

Re: water temp gauge

The only temperature gauges that I have on my boats are OMC/BRP kits. They work well and come with everything that you need - including instructions.

 

[CharlestonMako]

Re: water temp gauge

I am not trying to hijack your thread, but I am trying to do the same thing (get temp/tach/etc gauges working in an 88? Johnson 140). I was referred here by a ClassicMako member, to try and figure this out. All the information I have been given says that these motors already have temperature information coming out through the harness or a wire cut off through under the cowling. Is this incorrect? It seems much simpler just to buy the turnkey package with the screw in sensor. Does anyone know where to buy the entire package? Thanks.

 

[ezeke]

Re: water temp gauge

The only stock temperature information source is the switch on the cylinder heads of your engine. The port switch has a on/off tan wire that sounds the horn at the helm when you overheat and a black and white wire that controls the powerpack functions of QuikStart and S.L.O.W. none of that informtion is in a form that will give you a heads-up.

The starboard switch is strictly on or off and has only the tan wire. By the time the horn sounds, the engine is already nearly hot enough to boil water, which is why many have added the temperature gauges.

You can buy the aftermarket kits here at iboats or the OMC/BRP OEM kits from any local parts dealer, or online at this link: http://shop2.evinrude.com/ext/index.aspx?s1=8dcb6c8c1adbf5ad955286e026c798c6

BTW, I recommend that you don't guess on the application - get help from an authorized outboard service department.

 

[CharlestonMako]

Re: water temp gauge

ezeke,

Thanks, thats just what i needed to know... now i really feel like i am taking over your thread (sorry canman), but maybe this will help you too. Will this gauge work for our engines?

http://www.iboats.com/Water_Temp_Ki....248019--**********.721665966--view_id.169211

This is the one that would match my other gauges (dont know about canman's). And it comes with a Teleflex "J-sender". Anyone familiar with it? Is this the one that will crew into the already tapped threads in our blocks? It doesn?t say the temp range, does anyone know if it is right for an outboard (ie lower temps than I/O). Also, do you think the idiot proof, "Cold/hot", is enough? Thanks for the help... and again, i hate to butt in, but why start another thread for almost identical info... Thanks.

 

[ezeke]

Re: water temp gauge

The J sender notation just says you have to use a J sender with that gauge for it to work right. Since the correct sender is in the kit, if you buy the whole kit you will get the correct sender for the gauge.

Teleflex has a great service department even though they don't retail the units directly. If you contact them and tell them what you are doing, I believe that they will give you the specifics that you need. http://ww2.tflx.com/contact.html

 

[canman]

Re: water temp gauge

hi everyone . i am glad my post could help a few people . right now i am looking at afoot of snow , so it will be quite awhile before i do anything . thanks for all your help .

 

[CharlestonMako]

Re: water temp gauge

Too bad about the snow... down in charleston SC, its been 65 and sunny (dont mean to rub it in), so I've been getting a lot of work done.

It seems like the best bet for me is a crew in type sender right into the block in the pre-drilled/tapped holes. Canman... is that what youve decided? the only thing i am concerned about is this comment:

A temp gauge intended for I/O's is generally calibrated 120 - 250 degrees give or take a little on the high end. If you attempted to use that gauge on an outboard the needle would hardly ever get off the 120 peg.

I talked to the teleflex tech support, and he recomended a gauge calibrated in 120, 140, 160, 200, and 220 increments (the gauge in the same series as currently on my console). I also spoke a guy who said i can expect 140deg cruising temps and 160deg idleing temps (i have no idea), which would make the above gauge seem ideal. Silvertip seems to disagree with them... or am i reading this wrong? Will a gauge calibrated at 120 lower end be useless to an outboard? Canman, what gauge did you decide on? thanks

 

[ezeke]

Re: water temp gauge

To CharlestonMako:

The 160 Idle and 140 running temperature ranges are exactly the ranges that my 1988 140 runs in. My system should be the same as yours.

I would expect that the Starboard side would be slightly different, but I don't have a switch to check it - maybe someday....

As soon as the engine is started, it goes into QuikStart which advances the throttle. When the temperature reaches 96 degrees, Quikstart kicks out and you feel it. Shortly after that the temperature of the water reaching the thermostats from inside the engine reaches 140+/- degrees and the thermostats begin to open and close. From that point on, the temperature on the gauge should stay somewhere between 120 and 180 all of the time. I don't see a problem with a wider range of temperature on the gauge, but I also don't see the necessity for it.

The main thing for me is knowing that I not in the overheat danger area, and knowing that my thermostats are not stuck open, causing the engine to run cold. Big bore loopers don't like running cold.

In other words I get used to where the gauges are reading and would be aware of a change, just like I read the gauges in my car.

 

[CharlestonMako]

Re: water temp gauge

ezeke, wow, that is exactly the information I was looking for... thank you. I am quickly realizing that this site is as valuable a resource as ClassicMako.com.

One more quick question and I think It will be time to buy/install some parts. Are you using a screw in type sender right into the unused threaded hole next to the cylinder? If not, If I use one can I expect to get around the same temps as you, without much decrease in accuracy/reliability? It is just hard for me to believe that this type sender could accurately measure the interior water temp? but I guess it does. Thanks a lot!

 

[Silvertip]

Re: water temp gauge

In my view the COLD-NORMAL-HOT calibration is useless because NORMAL (center of the gauge) may be normal for one engine but not another. I much prefer a gauge calibrated with real numbers on so I know how hot NORMAL is.

 

[ezeke]

Re: water temp gauge

To CharlestonMako:​

I was assuming that we were addressing the conversation that you had with teleflex. If that is the reference then I would use the prepared tapped hole on the cylinder head. I would probably use the tapped hole on any gauge of that type.​

Some of the forum members have installed gauges for each cylinder head and some have wired two senders and a switch so that they can read either cylinder head from one gauge.

The looper cylinder heads have a water cavity cast inside them, the tapped hole is cast into the water cavity. The face of the cylinder head is in constant contact with the water that is circulating through the engine. It is about as close to the water as you can be without having the sender actually in the water.​

 

[CharlestonMako]

Re: water temp gauge

ezeke, I was also talking about the sensor recommended by Teleflex. It sounds like that is the one for me? thanks. What kind of wire is typically run from the sender to gauge for this type of data application? I am assuming maybe 16AWG marine stranded wire?

Silvertip, I agree about the ?Cold/Normal/Hot? gauges. The one I am looking at is not labeled per say, but according to the Teleflex guy, the graduations on the gauge DO correspond to the specific temperatures listed in my post above? so you just have to memorize them if you want to know the temperature value numerically. With this in mind, would this gauge meet your standards?

 

[canman]

Re: water temp gauge

hi everyone . the gauge i was looking at starts at 60 degrees and goes up to 220 degrees and comes with a screw in sender . the motor i bought is still at the dealers . i have to take the boat to him the end of april and they will install the motor and set it up for me . the motor was just rebuilt . right now i am trying to get my snow blower to go .