Yamaha 70hp alarm buzzer

Fugley01

Cadet
Joined
Jul 21, 2009
Messages
9
Took the kids fishing in my 87 Tracker with 87 Yam. 70hp yesterday. This is the first time I have had this boat on the water. I picked it up to replace an older tiller model. I premixed the fuel as I am not sure if the oil injection is working properly.
Went accross the lake @ 3/4 throttle no problem. Shut down to rig fishing lines then started trolling. almost immediatly the alarm started (oil or temp ) I shut the motor down and restarted it but the alarm was still sounding. I sped up a bit and the alarm stopped but couln't get any rpm's must have activated the limiter. When I got home I checked the thermostat and tried it in hot water and it opened fine. Should I replace the impeller (pump kit)? I also tried testing the thermal resistor on the cyl. head but couldn't get a reading with my ohm meter unless it was set to meg scale. Should I replace the sensor as well? Maybe I'm still missing something. I believe the boat sat for ot least a season without being used.

TIA

Mike.
 
Last edited:

DMSOUTH

Cadet
Joined
Nov 19, 2007
Messages
27
Re: Yamaha 70hp alarm buzzer

Was it peeing? First place I would start is with the water pump.....
 

Fugley01

Cadet
Joined
Jul 21, 2009
Messages
9
Re: Yamaha 70hp alarm buzzer

There was water coming from the telltale, the boat has a water pressure gauge but it isn't hooked up. I'm not sure if it uses a tube or if it uses wiring as the sending unit was removed and the port in the head has been plugged.
I have read on various forums that the Yamaha triples have a tendancy of their water passages blocking up with crud.
Being in central Canada, ( Thunder Bay) I don't believe it has ever been in salt water. The tach isn't working yet (parts on order) so I don't know what the actual rpm's were when the limiter kicked in, but I was trolling at the time.
Is there a chance that the thermistor is buggered and there isn't a problem with the cooling system? I'm ordering a pump kit, thermostat and thermistor anyway, as I don't know when it was last serviced.

Thanks

Mike.
 

Profittakr

Seaman Apprentice
Joined
Aug 24, 2009
Messages
38
Re: Yamaha 70hp alarm buzzer

This sounds like a similar problem to what I had happen to me on my '88 70hp Yamaha last weekend. (see my post) Please let me know how you have made out with this. I too have checked the thermostat but that was fine. I did not get an alarm but after investigation it looks like someone had spliced wires previously and maybe connection was not good. Buzzer if functional now but have not had it on water to retest. My tach also not accurate so I don't know the correct rpms but it cut to about 1/3 to 1/2 throttle - ran smooth but no high rpm. Hopefully this weekend will retest on water.

Please let me know what you have found, if anything.
 

BaileyFish

Cadet
Joined
Jan 8, 2006
Messages
17
Re: Yamaha 70hp alarm buzzer

Just finished mine up 90/hp Yamaha similar issues. Check popit, tstat, water pump... most likely I think it's the water pump... but this would be a good time to run through the full system and the tstat and poppit are pretty easy to check for peace of mind.

Andrew
 

Profittakr

Seaman Apprentice
Joined
Aug 24, 2009
Messages
38
Re: Yamaha 70hp alarm buzzer

I have checked t-stat and temp sensor and both are working fine. No poppet on 70hp.
How long did it take you to go through the water pump and install new impeller?
Also, I have tested the ground circuit on the oil level tank and it is good but I cannot figure out how to remove the oil level guage unit from the oil tank. It looks like it is just a rubber stopper holding it in there but I for the life of me cannot get it out without destroying the tank or the top of the unit. Anyone knowhow to remove it?
Any way to test if oil injection if REALLY working? I have not been premixing and have had no issues so I don't suspect that but just want to be sure. I assume if it was not working the engine would have siezed by now.
 

divinginn

Petty Officer 3rd Class
Joined
Aug 12, 2007
Messages
77
Re: Yamaha 70hp alarm buzzer

My 40 was buzzing,it turned out to be a impeller. You can check the oil pump by pulling one of the oil line off that come from the pump while running,the manual will tell you how much oil should be coming out. Do you have oil in the tank? it will buzz when it gets to 1/4 tank,you can also read the light codes on the front of the motor,you need a manual to tell what they mean.
 

Profittakr

Seaman Apprentice
Joined
Aug 24, 2009
Messages
38
Re: Yamaha 70hp alarm buzzer

Definitely oil in the tank. Was 1/2 full and I put in the rest I had before I went out and was 3/4 full. Still 3/4 full so I know it is not the quantity of oil. That is why I am wondering if the oil level sensor is at fault. Personally, I think it needs a new impeller. It still streams ok but I know it have been about 5 years since it was done. I just got it myself last year and did not do it. Previous owner says it was about 5 years ago so it is time. Just want to know how much time to budget for the job. Can i do in in 2-3 hours?
Not sure what you mean by 'light codes on the front of the motor'. I don't have any light on the motor, only on the Yamaha multimeter on the dash and they don't indicate anything is wrong.
 

Fugley01

Cadet
Joined
Jul 21, 2009
Messages
9
Re: Yamaha 70hp alarm buzzer

Here is what I have done so far.... I replaced the lighting coil,.....that fixed the no tachometer problem. I replaced the thermostat, temp. sensor and installed a water pump kit. The impeller that was in it looked fine but since it was apart I figured it should be done.
I am not sure, but while I was working on the motor I noticed that a ground wire on the harness to the oil tank was not secured to anything, it was just bouncing around.
The question here is..... if the oil tank ground is bouncing around and making intermittant contact, could this be the reason I got the alarm in the first place? not an overheat but an oil alarm? Before finding the loose ground wire the only oil light I would get when the motor was running was the yellow (3 lamp system) even with a full oil tank. now that the ground is fixed I get the green light. I want to try it out again but I would like to know if anyone can think of anything I may have missed before going out again.

Thanks

Mike.
 

Scott/Tampa

Cadet
Joined
Jul 23, 2007
Messages
14
Re: Yamaha 70hp alarm buzzer

Mike:

This is my first Yamaha. It's a 1986 40hp. It hauls butt...no, I should say it used to haul butt! Did you ever figure out how to get that oil sensor out? I have to take mine out because it is definitely bad. I can't figure out how to get it out. The manual I have does not address this (as usual with these DYI manuals!). There is what appears to be a rubber boot on top where the sensor wires come out. I have tried to lift that boot and it doesn't seem to want to come up/off. I am afraid I will ruin it. Why should this be so difficult? Anybody? Please help...son is beating me up cuz he wants to get out fishing!!!

Scott
Tampa
 

Profittakr

Seaman Apprentice
Joined
Aug 24, 2009
Messages
38
Re: Yamaha 70hp alarm buzzer

I never got the oil stopper out. The guys at the Yamaha shop said it just pulls out but that it is VERY difficult. They said that you could lubricate it with dishsoap or something and let it work its way in and then pull it out. If the soap mixes with the oil you will want to change it out but I would not expect you to use that much soap that that would be a problem.

It turns out that that was not my problem so I did not mess with it any more.
If you keep the oil level full and monitored, you can disconnect the oil sending wire on the starboard side of the motor and should will prevent the computer sending the engine into rpm reduction mode and you should be good to go. Just keep an eye manually on the oil level each outing. BUT, work on getting the system fixed. This would be a temporary solution as I am not one to bypass warning signals as you will burn up your engine if you run out of oil.
Good Luck! Please post back if you ever get the stopper off and tell us how you did it.
 

Scott/Tampa

Cadet
Joined
Jul 23, 2007
Messages
14
Re: Yamaha 70hp alarm buzzer

I am beginning to think that the sensor may be OK. The oil level is about half way down. I am not sure when it is supposed to alert you, but maybe the float is a little messed up. Will let you know when/how I get that assembly loose and out.

Thanks for the quick reply...you guys are all great!

Scott.
 
Top