Logo
FULL SITE MENU

2017 Honda BF60 Temp alarm

G

Goneagain4

New member
Newbie member, just joined the site. Hoping to get some help on neighbor's engine.

Pontoon boat with the Honda 60 4 stroke on it, approx 225 hours. Original owner since new. At 3000 RPM or higher, the temp alarm sounds and lights up red. It has the round gauge with the green oil light on while running, temp warning, check engine light. Keep it below 3000 rpm and it goes all day with no alarm.

Since he had not done any maintenance, here is what I did:
1. Changed oil and filter. Changed foot oil with new o ring seals.
2. Replaced complete water pump kit, cup, impeller, housing, etc, OEM kit.
3. Replaced thermostat, OEM.
4. Replaced temp sending sensor, OEM.
5. Removed/inspected O2 sensor, spark plugs. Plugs look normal, all 3 plus the sensor are clean.
6. Replaced fuel/water separator, no water or debris in filter. Engine fuel filter is clean, float at bottom of filter.
7. Repaired starter brushes, that was done first when it would not turn over.

Don't think it is a true overheat. You can keep your hand on the thermostat housing when the alarm goes off and engine block does not feel overly hot. Switch it off and restart and everything is normal again until you exceed 3000rpm. Tried to use infrared temp but unit was not working. Telltell shoots good stream. Engine runs smooth, have not done compression check but plugs look good and power output is normal.

I think the issue is also load related. Only alarms when in gear under load, neutral at 3000 rpm and it does not alarm. The alarm will go off even before engine has a chance to warm up good. Start it, idle for a couple minutes, go to 3000 and it alarms after about 10 seconds. Shut off, restart, good until you exceed 3000 again. Does not require cool down to reset alarm. Neighbor says ongoing problem started at 4000 rpm but now is down to 3000rpm.

The engine is clean, used in fresh water and kept on cradle when not in use. I'm the only one that has worked on it so far but I'm running out of ideas. Any help here would be appreciated!
 
Hi,

What a great neighbor!

I don't know but I seem to recall something similar going on in a couple of posts on this site and it had something to do with the oxygen sensor. I know some Honda O2 sensors have given problems but I don't work on these so I don't have any specifics to give you or how to properly troubleshoot. Maybe try unplugging it and see what happens??

The only other thing that comes to mind might be the alternator.

You can do a Google search for checking ac ripple at the battery and try that or, unplug the alternator and see if the symptom changes.

Hopefully someone else has better answers.

Good luck.
 
Thanks. We are both old retired guys and he spent 10 days helping me put a new roof on my place. Least I can do is mow his yard sometimes and try to help out with what I can. He has no trailer so I work on his boat with mine under it. Taking it to a repair shop would be really inconvient.

I did try unplugging the temp sensor and 02 sensor. Both times engine started with the alarm on when unplugged. I'll look into the alternator and see if it has any related issues. Battery stays charged fine so I did not suspect anything with the alternator.

I've done all the maintenance I would have done on my motors with the exception of the anodes. Took off the one on the foot to renew the conductivity but anode looked fine.

At this point I've taken all the obvious and less expensive shots and taken care of the necessary maintenance. Even heated the 02 sensor tip when I had it out based on a recommendation that it may have been fouled. The sensor is north of 300.00 so really hate to gamble without definite suspicion it is bad. I cannot locate a poppit or relief valve on the motor or in the schematics. I'd clean that next if I could find one.

I've read that the codes on this engine can be pulled by manipulating the kill switch somehow after shunting a connector under the powerhead. The check engine light is not on so I don't know if any codes are stored. If anyone wants to share that procedure with me I'll try that next. I can scan auto OBDII but I guess boats are not standard connectors.
 
Well....what great NEIGHBORS then!

I have the code procedure shared here by chawk_man, but I too am old and don't even remember working anymore so getting it uploaded from my phone has defeated me.

But that was for the mid 2000 200hp/225hp anyway and I don't know if it would work for your friend's motor.

Here's where you need to really use caution since I really don't know if this has the capacity of damaging the computer if you (or I) get it wrong!

You could have a look under the electronics cover though and see if it has the 4 pin red service connector. The process was simply to use a paper clip and jumper the lime green wire to the black wire then turn ignition to on/run and watch for the blink codes.

A 1 blink code is for.the O2 btw.
 
Got factory manual, went thru several pages of testing. Verified it is a false temp alarm, thermostat housing never got over 140F. Checked codes by shorting diagnostic connector black and lime wires. Cleared codes. Got to MAP Sensor test and it failed. Waiting on new MAP sensor, should have results by end of weekend.
 
Well, I will be interested to see if it turns out that a faulty MAP sensor will cause an overheat alarm. If so, that wouldn't speak well for Honda's engine management "architecture".

Sort of like:"Hey buddy! You've got a problem! So....
.... let us confuse the (bleep) out of you!"

Looking forward to your update and, hopefully, success.
 
I agree, but you just gotta start somewhere and keep testing until you find something. The sensor may not fix the issue but it may be a step in the right direction to isolating something else. I could not figure how the MAP sensor would trigger the temp warning, more like it should turn on the MIL light.
One thing I find interesting on a lot of forum post, you see all these issues put out there for people asking for help on problems. I've noticed that most of these threads just fizzle out and there is really no resolution ever posted. I for one hate things that do not work properly, whatever it is. I'll stay with this Honda problem until I exhaust all possibilities and share what I learn. At least I'm saving my friend from a trip to the dealer so far. I'd hate to be paying for the hours I've spent diagnosing so far.
 
Yeah, I have gotten used to not seeing any resolutions posted. I think the majority are because the owner can't find one and simply gives up, sells the rig and really can't stand to even think about it any longer. I can sympathize with that.

I try to help people here but it's obvious that I don't have most of the answers needed. I try to just get the thought process going and be willing to discuss the problem. But many just want a quick, easy fix to their issue and, if they don't get it, they move on to another site and never come back.

That's why folks that are willing to follow through and tell us the results...good or bad...are so valuable to me. I came here to learn myself and that's how I gain knowledge.
 
I am following your thread with interest. i have a thread going here on my bf30. My motor will not run for more than a minute with the temp sensor plugged in. I have tested the sensor, thermostat and all connections to cdi. I am currently waiting on a new sensor.

i had this issue occur after putting the boat in service after storage. The boat also had a carb issue. Which was made much more complicated by this safe mode (if thats what it is) issue.
 
Okay, BF60 alarm over 3000 RPM, temp light comes on, correct? This sounds like a water pressure issue. You can't disconnect sensors to experiment on EFI motors, they alarm instantly. They don't log codes for overheat or oil pressure alerts either. Couple of things to check. Firstly, are you certain the water pump grommet is properly fitted at the outlet? Remove the plastic water jacket cover on the port side to get access to the internal anodes, that is the one the thermostat sits in. At the bottom of the water jacket there is a slotted hole which can get blocked by sand, weed or other debris, make sure it's clean by using compressed air to blow out visible passages. Also check the passages behind the thermostat are clear too, they can also get blocked. Do this first and let me know what you find. Don't stuff around changing sensor, the issue is an overheat at high rpm due to insufgicient water flow.
 
iang6766, I think you are dead right. I have been wrong diagnosing this problem from the start. I don't like being wrong, but I was. I overlooked the obvious.
Worked on motor today. Put new MAP sensor in, no change. Not surprised. Got better angle with laser temp gauge, registered 180, too hot at sensor base. Pulled thermostat and temp sensor. Used air compressor with thin outlet and got gobs of crud out of thermostat area and temp sensor hole. The more I blew, the more small particles came out. Tried flush connector with hose. Nothing came out with flush hose. Really surprised because my Yamahas all flow hard on hose flush. Owner told me he never flushed motor. Put vinegar in thermostat area, then more compressed air. More junk came out. Put motor in water and ran it with no sensor or thermostat. Great flow from water pump, it is pumping as expected since it is new.
OK- lots of crud came from block, still no flush water from hose thru block or thermostat. That is bothering me. Put boat in water, ran down river 5000 rpm, no overheat after 15 minutes.

Problem is close to being solved! Looks like I will continue cleaning the block passages until I get good flow thru head area from hose flush.
My main problem is that I overlooked the obvious. My bad. Never overlook the obvious when troubleshooting.
I'll continue cleaning the block this weekend. Sunday I'll post if I got the hose flushing satisfactory. I suspect between the water quality in my area and maybe smaller cooling passages in the Honda, corrosion is the issue.

I'll remove side cover and clean passages as suggested if I can't get hose flush to work. Thanks for the suggestion, it looks spot on!!!!
 
Goneagain4 said:
iang6766, I think you are dead right. I have been wrong diagnosing this problem from the start. I don't like being wrong, but I was. I overlooked the obvious.
Worked on motor today. Put new MAP sensor in, no change. Not surprised. Got better angle with laser temp gauge, registered 180, too hot at sensor base. Pulled thermostat and temp sensor. Used air compressor with thin outlet and got gobs of crud out of thermostat area and temp sensor hole. The more I blew, the more small particles came out. Tried flush connector with hose. Nothing came out with flush hose. Really surprised because my Yamahas all flow hard on hose flush. Owner told me he never flushed motor. Put vinegar in thermostat area, then more compressed air. More junk came out. Put motor in water and ran it with no sensor or thermostat. Great flow from water pump, it is pumping as expected since it is new.
OK- lots of crud came from block, still no flush water from hose thru block or thermostat. That is bothering me. Put boat in water, ran down river 5000 rpm, no overheat after 15 minutes.

Problem is close to being solved! Looks like I will continue cleaning the block passages until I get good flow thru head area from hose flush.
My main problem is that I overlooked the obvious. My bad. Never overlook the obvious when troubleshooting.
I'll continue cleaning the block this weekend. Sunday I'll post if I got the hose flushing satisfactory. I suspect between the water quality in my area and maybe smaller cooling passages in the Honda, corrosion is the issue.

I'll remove side cover and clean passages as suggested if I can't get hose flush to work. Thanks for the suggestion, it looks spot on!!!!
Click to expand...
Problem solved!

Removed side cover thermostat housing (Thanks iang6766!). Cleaned and flushed. Minor debris came out. Hose flush still not working so I removed the starboard side mid-cowling to gain access to flush tube. Removed tube. Started poking with a stiff weedeater line but would go more than about 3" in. Kept poking until it finally broke though and pushed it in about 6-8 inches. Got some calcuim/scale out. Hooked up hose, did a 5 minute flush with thermostat housing back on but thermostat out. Put everything back together and put boat in water. Ran 10 miles, half of that at 5000 RPM. No overheat, everything normal. Instructed owner to use flush with hose once a month. Everyone is happy, think we will be OK now!
 
Something wierd on the thread, took 2 days to post and had to do the quote to finally post the last message. Well, anyway, fixed and done!
 
Back
Top