Overheating alarm question

cdory25 · Posted: Tue Feb 18, 2014 8:18 pm Post subject: Overheating alarm question

I'm hoping this has happened to someone else so they can help me figure this out. As I prepare for a lengthy journey traveling 100+ miles south on the St. Johns river to the St. Johns River gathering in a week, I remembered a problem I have had since I've owned Blues Cruiser.

After cruising above 4k rpm for a while (sometimes you just gotta get somewhere) the hot engine alarm comes on (light next to the key) making an awful, annoying and loud noise (beep, beep, beep...) The only way to stop it is to turn off the motor and wait 5 minutes or more.

The motor (Honda 135) doesn't appear overly hot and the 'pee hole' is clear and flowing normally. The motor has 500+ hours on it and was serviced last summer including a new water pump impeller. I could disconnect the alarm but don't want to risk damage to the Honda. Any ideas? I don't have time to take it in for a repair and still do the float next weekend.

Thanks!
John

BrentB · Posted: Tue Feb 18, 2014 8:41 pm Post subject:

How many thermostats does it have and when were they last replaced? I am thinking it is the thermostats or a sensor
m2cw

T.R. Bauer · Posted: Tue Feb 18, 2014 8:59 pm Post subject:

I think your motor could be having a sensor issue. Normally when and if they really do overheat you know it. But, I'm not sure that when the alarm goes off the temperature is actually high enough to call it a real overheating condition - just getting close. Checking the thermostat never hurts either and it could be partially stuck closed.

cdory25 · Posted: Tue Feb 18, 2014 9:00 pm Post subject:

Possibly. That's what I'm hoping a knowledgeable C-Brat can tell me.

BrentB · Posted: Tue Feb 18, 2014 9:06 pm Post subject:

I bought Yamaha Diagnostic Software and cables to pull codes from the ECM. Has anyone scanned it for codes?

DaveS · Posted: Tue Feb 18, 2014 9:07 pm Post subject:

I vote Thermostat. I keep a spare on board and it only takes 15 minutes to change it out. Laughing

cdory25 · Posted: Tue Feb 18, 2014 10:20 pm Post subject:

thataway · Posted: Tue Feb 18, 2014 10:35 pm Post subject:

Most likely a Thermostat, but also there may be salt build up. Do you always rinse the motor with fresh water after each salt water use? I would not ignore the alarm. Also a IR therometer should be part of the kit, to check the temps.

cdory25 · Posted: Tue Feb 18, 2014 11:17 pm Post subject:

texasair · Posted: Tue Feb 18, 2014 11:44 pm Post subject:

May not be the motor. I had an intermittent hard to find overheating alarm.

Turns out it was not the motor at all. Problem was in the controls located in the shifter and throttle.

DaveS · Posted: Wed Feb 19, 2014 2:23 am Post subject:

DaveS · Posted: Wed Feb 19, 2014 2:27 am Post subject:

cdory25 · Posted: Wed Feb 19, 2014 9:43 am Post subject:

BrentB · Posted: Wed Feb 19, 2014 11:38 am Post subject:

Here is a kit
http://www.brpdiagnostics.com/honda-dr-h-outboard-diagnostic/

There may be others but you can search the web for them

I would invest in a set of Honda factory manuals, too

m2cw is replace all thermostats first

Oh and the gas gauge has suddenly stopped working, probably because I didn't have a full tank last time it was stored.

I would suscept a loose connection at the meter or tank , blown fuse or a bad ground

I purchase parts locally and on the net
Boats.net and BOE at http://www.boemarine.com/categories/honda-engines-gens-pumps/outboard-parts.html

sale Honda parts (both have online diagrams) but I would contact a local dealer first for a couple reasons....... they work on the OBs on a regular basis thus knowledgable and they have sevice or tech bulletins which are invaluable sources of information but I dont access to them .. second I am not a master mechanic sometimes it is money well spent to have a pro perform the work ....folks like Marc at Wefings, Les Lampman, Matt Gurnsey at Kitsap are on the list and freely provide keen insights and good service with peace of mind

best

cdory25 · Posted: Wed Feb 19, 2014 12:59 pm Post subject:

I talked to the BJ at First Coast Marine in St. Augustine and he thinks that replacing the thermostats, that's right, there's two of them, at $70 is the cheapest fix and I should be able to DIY. If that doesn't fix it then it would pretty much have to be the sensor. They will be in Monday so thanks to all for your help! Maybe I'll try a wax thermometer after to be safe...St. Johns gathering next weekend!

Thanks!
John