temp gauge

[ferdly1]

i have a 1988 Evinrude 90hp with tilt and trim.. I want to put a temp gauge on my boat. I cant seem to find the thermostat for this motor or any other place to hook up a sensor. I looked at a parts breakdown of the motor and did not see a thermostat there either. Maybe I am missing something. Any suggestions would be appreciated.

 

[Silvertip]

Re: temp gauge

Yes you are. You only need a contact style sender. Thermostat controls engine temp but has nothing to do with adding a temp gauge.

 

[hidef]

Re: temp gauge

See item 78 for the T=Stats

Johnson Midsection Parts for 1988 90hp J90TLCCA Outboard Motor

See Item 35 for the temp switch

Johnson Cylinder & Crankcase Parts for 1988 90hp J90TLCCA Outboard Motor

 

[glenn property of pam]

Re: temp gauge

on my motor I used a 1/4 npt sensor and screwed it in to the side of the block with a little heat transfer paste. There a un-threaded hole that is blanked off in the block top right hand side that the sensor will grip into. Once the sensor is installed just run one wire to the sense on the gauge and daisy chain 12v of another gauge.

 

[ferdly1]

Re: temp gauge

Got it thanks for the help.

 

[ferdly1]

Re: temp gauge

I was gonna post some pictures this site will not let me upload photos. I found 2 places to mount sensor neither one is threaded. I guess I will have to glue it in place. You mentioned heat transfer paste. Is that the same stuff used to hold heat sinks to computer processor chips and would it be able to hold sensor to engine block?

 

[minuteman62-64]

Re: temp gauge

I was gonna post some pictures this site will not let me upload photos. I found 2 places to mount sensor neither one is threaded. I guess I will have to glue it in place. You mentioned heat transfer paste. Is that the same stuff used to hold heat sinks to computer processor chips and would it be able to hold sensor to engine block?

There are two different substances that may be of use. There is a heat transfer grease, that creates a good thermal transfer but has no adhesive capability. There is also a heat transfer epoxy that creates good thermal transfer and is also a good adhesive. I think the epoxy is what you are describing for holding heat sinks to chips.

 

[ferdly1]

Re: temp gauge

where do I get heat transfer epoxy. I have thermal grease thats what I use for computers,it has no adhesive qualities. I called an electronics store and he was clueless on epoxy.

 

[minuteman62-64]

Re: temp gauge

where do I get heat transfer epoxy. I have thermal grease thats what I use for computers,it has no adhesive qualities. I called an electronics store and he was clueless on epoxy.

These folks have it: www.articsilver.com

There is an on-line piece from a guy who used it to install a thermostatic switch on his Honda OBs. I corresponded with the articsilver folks, asking about that sort of application, and got no encouragement. However, it has been done

Here's the info from the poster:
If anyone is interested in installing heat sensors and gauges on their outboard send an e-mail to to me at wdneal@sdrnet.com, and I will send you the writeup with pictures.

He responded to me with his writeup (a Word doc) within a day. I'd attach it here, but it won't copy for some reason.

 

[emdsapmgr]

Re: temp gauge

Most folks mount the contact sender with a special "Z" bracket. Usually a head cover bolt is used to hold the bracket (and sender) tightly to the head. The temp switch mentioned above is just that, an on/off switch. It can't be used to produce a variable voltage output to drive the temp gauge.

 

[ferdly1]

Re: temp gauge

Thanks for the info guys. I tried to take a short cut and as usual that backfired. I ordered a teleflex gauge from ebay and a temp sensor also from ebay. The gauge made it but the sensor is stuck in Michigan somewhere since last wednesday. That is the second order that usps has lost in two months. The postal service needs to find a new line of work. I tried getting automotive contact sensor but it would not work. A boat dealer here sells the whole gauge and sensor as a kit for 100 bucks. Just didnt want to shell out that much cash. Oh the sensor I ordered from ebay did have a z bracket wherever it is now.

 

[glenn property of pam]

Re: temp gauge

minuteman the holes are un-threaded they are slightly bigger than 1/4npt so when the sensor goes in it will bite into the aluminum of the head. (npt threads get wider the further up you go so it goes in then a turn and a half will be enough to hold it). The heat paste is because the end of the sensor will not be touching the end of the hole so the paste makes up the gap and allows heat transfer. This is how my engine is done. On the 70hp I had I made a Z bracket as emdsapmgr suggested.


attached in a pic of the sensor on my 120.

 

[emdsapmgr]

Re: temp gauge

You need to match the temp sender with the gauge, or you will get strange readings. Probably why the automotive one did not work. If they are both Teleflex you should be ok.

 

[ferdly1]

Re: temp gauge

i went to the dealer for sending unit still doesnt work. Could be gauge I guess. When i ground wire going to sending unit gauge pegs. I do have a question. The wire marked ignition on the gauge. I just have 12 volts coming from fuse panel to the ignition post on the gauge. Do i need to hook it up to the purple wire on the ignition switch.

 

[emdsapmgr]

Re: temp gauge

I'd look for another source for power for that gauge. You don't want to put too much load on the ignition switch. The engine system itself uses a small 20 amp fuse. That fuse will take the addition of a tach with no problem. When you get to adding too many other accessories onto the switch, it won't be long before the bilge pump kicks on and the engine fuse will blow. Not a good thing if you want to start it when you are in the middle of the lake. Most dash electrical items need to be fused direct to a main fuse block which will be fused direct to the battery. (not through the ignition switch.)

 

[submariner1980]

Re: temp gauge

IMHO all gauges thru IGNITION switch.
Bilge pump, navigation lights, accessories direct to the battery thru fuse.
I had to use AcuRite Wireless Digital Thermometer on my 70673. Put the probe under hood close to head. Enjoy in watching air temperature and under hood.

 

[ferdly1]

Re: temp gauge

Yes i have it wired thru fuse panel although directions say to wire thru switch. Was just wondering if it made a difference for some unknown reason. I went ahead and ordered a gauge and sensor together. Should have done that from the start, I was just trying to be cheap. Thanks for evryones help and comments. This is a great site. Thanks to this site, gonna try to repaint my boat. Lot of good info here.

 

[ferdly1]

Re: temp gauge

Oh here is something i did want to share. I use my boat exclusively in saltwater,so corrosion and deterioration of electrical components is a constant battle. I just rewired my boat replacing most wires and trying to make most connections as waterproof and corrosion resistant as possible. One thing I did was get a tupperware bowl from dollar tree and put my small fuse panel in side of it. I drilled holes in the side and put in grommets to run wire thru. I also mounted woodenn block using 4200 adhesive under my steering console so i could mount my fuse box setup to it without drilling holes into boat. i did use wood screws to mount box to block. The cover comes off easily providing quick access to fuses and wiring. And i hope it will keep my fuse panel from coroding as this is the second one i have replaced due to corrosion. I have $2.50 in the plastic box and $3.00 in the grommets.