Sniderah
Cadet
- Joined
- Jun 10, 2008
- Messages
- 7
I have a 1988 135hp Mercury motor (white Mercury - Ser# B334320) on an 18' Searay Seville. I have had an on-going intermittent problem for the last 5 years where the alarm will beep (beep, beep, beep...) sometimes at initial start-up or while running but it is only intermittent. When this occurs I have verified the proper level in the oil reservoir tank on the motor. I have taken it in for service 2 or 3 times and have been told that there is no problem. It is an intermittent issue so is hard to diagnose. The motor runs fine, smokes and maintains 140 F without a problem. I have read all of the posts on this forum related to this issue. This year I hope to figure it out. Here is what I have done this year:
- replaced the oil float switch in the engine oil reservoir tank. After installation, turning the key would give a constant beep. I disconnected/reconnected the water temperature switch, cleaned the terminals at terminal block 14 (insulated), verified the operation of the new oil float switch. This seemed to work. Now turning the key gave 2 beeps to indicate that the alarm circuit was working. I ran the motor in my driveway on the hose. Motor ran well for a bit and then started beeping (beep..beep..beep). Coincident with this alarm beeping, the tachometer needle was going up and down erratically.
- I read a thread that indicated that the tachometer could be a problem. Recommendation was to rotate the cylinder # selector on the back of the tachometer to clean up the contacts. I did this and sure enough turning the key gave the 2 beeps to indicate proper alarm operation. I ran it on the hose again and it seemed to do the trick. Problem solved.
- The next day I checked again and turning the key would give no beeps. I connected the round alarm unit to ground on the tan/blue wire, it sounded correctly. I then cleaned the terminal connections where the oil float, alarm module and rotation sensor are grounded to the engine. Worked again... turning the key gave the 2 beeps to indicate proper alarm operation. Problem solved.
- the next day I checked again and turning the key would give no beeps. I raised the motor up and down, opened up the cowl and then got a constant beep when turning the key. I opened up the clamp that holds the bundle of wires going into the engine and wiggled and tried to identify any obvious wiring issues. I disconnected the 8-pin plug at the engine pulled back the wire loom into the boat and uncovered the bundle of wires to check further back in the boat. I reconnected the 8-pin connector and turning the key would give a constant beep.
Essentially, every time I turn the key (without starting the engine), I will either have no beeps, a constant beep or 2 beeps (proper operation), however, there doesn't seem to be any way to identify cause and effect.
I have a new tachometer on order and I plan to install it this weekend, but I would appreciate any advice on what other diagnostic steps I should take. Another poster had similar problems and resolved his problem by replacing the trigger. I don't understand the electrical circuit well enough to understand how the trigger would be impacting on the alarm circuit and I am not sure if I should tackle replacing it myself.
Any help would be very much appreciated. I don't mind taking it in for service, but I am not confident that they will have the time and interest to diagnose it properly. Thanks.
- replaced the oil float switch in the engine oil reservoir tank. After installation, turning the key would give a constant beep. I disconnected/reconnected the water temperature switch, cleaned the terminals at terminal block 14 (insulated), verified the operation of the new oil float switch. This seemed to work. Now turning the key gave 2 beeps to indicate that the alarm circuit was working. I ran the motor in my driveway on the hose. Motor ran well for a bit and then started beeping (beep..beep..beep). Coincident with this alarm beeping, the tachometer needle was going up and down erratically.
- I read a thread that indicated that the tachometer could be a problem. Recommendation was to rotate the cylinder # selector on the back of the tachometer to clean up the contacts. I did this and sure enough turning the key gave the 2 beeps to indicate proper alarm operation. I ran it on the hose again and it seemed to do the trick. Problem solved.
- The next day I checked again and turning the key would give no beeps. I connected the round alarm unit to ground on the tan/blue wire, it sounded correctly. I then cleaned the terminal connections where the oil float, alarm module and rotation sensor are grounded to the engine. Worked again... turning the key gave the 2 beeps to indicate proper alarm operation. Problem solved.
- the next day I checked again and turning the key would give no beeps. I raised the motor up and down, opened up the cowl and then got a constant beep when turning the key. I opened up the clamp that holds the bundle of wires going into the engine and wiggled and tried to identify any obvious wiring issues. I disconnected the 8-pin plug at the engine pulled back the wire loom into the boat and uncovered the bundle of wires to check further back in the boat. I reconnected the 8-pin connector and turning the key would give a constant beep.
Essentially, every time I turn the key (without starting the engine), I will either have no beeps, a constant beep or 2 beeps (proper operation), however, there doesn't seem to be any way to identify cause and effect.
I have a new tachometer on order and I plan to install it this weekend, but I would appreciate any advice on what other diagnostic steps I should take. Another poster had similar problems and resolved his problem by replacing the trigger. I don't understand the electrical circuit well enough to understand how the trigger would be impacting on the alarm circuit and I am not sure if I should tackle replacing it myself.
Any help would be very much appreciated. I don't mind taking it in for service, but I am not confident that they will have the time and interest to diagnose it properly. Thanks.