1989 Mercruiser 3.0, Ticking noise

natsgrampy

Petty Officer 2nd Class
Joined
Aug 31, 2010
Messages
172
Was out Sunday and as I was cruising fairly slow, About 10 mph, approximately 2000 RPM, with a full boat. I heard a ticking coming from the engine compartment.
I decided to not go out into the sound and pulled onto the beach instead.
I let the engine cool for about an hour while the little ones explored the island.
I checked the oil and it was full, the oil pressure was fine when it started ticking. I checked the tightness of the plug wires.
I started the motor to see if I could isolate the noise. I was not able to recreate the ticking again.
I ran it for about 10 minutes and nothing. We decided to get back in and continue our trip. We spent 2 more hours just cruising around Long Island Sound.
Never heard the ticking again. Either then or at home while on the muffs.

I was wondering about the possible causes. Could it be any of the following?

The drive trimmed too high at higher RPMs?
A loose spark plug wire that I may have pushed back on. I set the timing the previous day and may have accidentally loosened one.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,568
Sounds are so hard to determine where your there listening, even harder from here. It could be as simple as

A loose spark plug wire that I may have pushed back on

Could also be a leaking spark plug wire, causing a spark to a ground. If wires are original might want to change them. Could also be a collapsing lifter, exhaust shutter, something else loose.
 

jhobbs26

Cadet
Joined
Jul 6, 2015
Messages
18
i just purchased a '97 bayliner 3.0LX. When i purchased the motor had not been started in 3 years and at the time of purchase i was not able to start the motor. After getting it home and the old fuel out i started it and it sounded like a noisy lifter. Decided to pull the valve cover off and found that the intake valve rocker arm stud had started to pull out of the head. Not sure if this might be a common problem with these motors or not, but might be something to look at. I've got the head at the machine shop right now getting all new screw in studs installed. Total job with gaskets and machine work is going to cost about $150 and roughly 3 hours of my labor to R&R the head.
 
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