What is this slight ticking in my engine?

[ryan04]

Hey guys, I've got a 91 bayliner capri with a 3.0L engine, it runs like a top and has never let me down. I bought it two years ago and even then it had the ticking but I didn't use it much until last summer so I never did anything about it, but now I want to fix it. When the engine is running at Idle it has a slight ticking sound, when I rev it up the ticking seems to speed up, when I'm in the water, after certain rev's it seems to go away but come back at lower rev's. Any idea what this might be? Oil is brand new, and full. I adjusted my timing,(it wasn't off but I thought it may help) but it didn't do anything. When I adjust the lean or rich mix of the carb the ticking does get quieter, but then the boat starts to idle rough cause of the setting so I put it back to where she's nice and smooth with the slight ticking comes back. Anyway you get the point any ideas? Thanks

 

[danond]

Re: What is this slight ticking in my engine?

A mechanical tick sound won't be cured by changing the carb settings. It's not a mixture issue.

This can be a number of things. Make sure your plug wires are all seated properly. You may be hearing a spark jumping the gap.

Use a mechanic's stethoscope and you should be able to isolate the sound to a specific area of the engine. Ticking (vs knocking) is typically valvetrain related. Knocking is typically crank/piston related.

If you don't have a mechanic's stethoscope, take a broom handle (without the broom end) or large dowel, touch the far end to the valve cover, then cover then cover the other end of the dowel/handle with your thumb wrapped over the top somewhat like a joystick with a fire button and stick the knuckle of your thumb in your ear until it's plugged. You should hear the internals moving around, and should be able to isolate the tick noise.

 

[n-toe]

Re: What is this slight ticking in my engine?

sounds like valve clatter,,if it runs like a top why tear into it?

 

[danond]

Re: What is this slight ticking in my engine?

sounds like valve clatter,,if it runs like a top why tear into it?

Really?

Figure out what's wrong, then decide what to do. Don't make any assumptions. It's good that you're trying to find and fix the issue.

 

[Maclin]

Re: What is this slight ticking in my engine?

Fuel pump lever play, lifter,spark plug wire shorting, etc... If the noise is really just a tick and is not getting louder or changing tone after each trip then leave it alone. Too many times what has started off as a "I want to make it perfect" quest has turned into driveability problems or worse as bogus theories are worked out.

If it has a stereo, turn it up...

 

[cbavier]

Re: What is this slight ticking in my engine?

ryan If you don't find the ticking source. Run the engine at night in the dark. If it's a spark plug wire or at the distributer. You can see it in the dark real easy. It sounds like a plug wire to me or a cracked distributer cap..

 

[BIGALF]

Re: What is this slight ticking in my engine?

Can you check the fuel pump. Sometimes that makes a sound when it is about to go.

 

[J. Mark]

Re: What is this slight ticking in my engine?

All engines make some degree of mechanical noise. While trying to find the source is a good idea, don't get to worried about it if the sound never changes from trip to trip.

 

[ryan04]

Re: What is this slight ticking in my engine?

Ok so I grabbed a long shaft robertson and stuck it in my ear and poked around the engine when it warmed up at idle. (on the muffs of course) So it sounds like the light ticking is coming from around the cylinder number 3 I believe it is. If your facing the stern it's the third cylinder down the line. I revd it up slightly and stuck the screw driver on it again and it's still ticking from that spot. Again, it's not obnoxious, but it isn't that beautiful marine sound I NEED to hear. I checked the distributor and all plugs are on tight and the cap is in perfect shape. It's definately coming from the engine and not any sort of electrical spark jump or short. So my guess is it could be a noisy lifter???... in which case how do you clean lifters? Thanks

 

[tlihou]

Re: What is this slight ticking in my engine?

Ryan:

Same thing happened to mine last year...right around this time. Same engine, but mine was a '95.

Anyway...we did an oil change and ran some of that detergent stuff through the engine. I forget what it is called but someone on here will know the name.
That did the trick for me. I went out for a rip with the detergent/oil running through the engine and the noise...stopped.

We came back and changed the oil again...pure fresh oil this time. And it ran fine all summer until I traded it in.

Good luck...

 

[dontask]

Re: What is this slight ticking in my engine?

Wear pad on fuel pump arm loose or missing?
Rocker arm mount stud backed off and or loose?
Lifter internal body frozen not allowing auto lash adjustment?
Automatic choke plate bouncing off of limit position?
Timing chain link broken (one of)?
Push rod bent slightly and now lifter is maxed out on adjustment ability?
"Taper grind" on cam shaft lobe worn away and now not rotating
lifter body which increases valve train wear (on that one valve
train)?
Spark jump?
Valve spring failing?
Crankcase/manifold ventilation valve pulsing (if installed).
Does it make the ticking sound still if you TEMPORARILY remove the
fan belt and start it?
Exhaust manifold leak?

 

[dontask]

Re: What is this slight ticking in my engine?

Ryan:

Same thing happened to mine last year...right around this time. Same engine, but mine was a '95.

Anyway...we did an oil change and ran some of that detergent stuff through the engine. I forget what it is called but someone on here will know the name.
That did the trick for me. I went out for a rip with the detergent/oil running through the engine and the noise...stopped.

We came back and changed the oil again...pure fresh oil this time. And it ran fine all summer until I traded it in.

Good luck...

You might have used a product called CD-2 detergent which frees up sludge and carbon on and in lifters.

 

[ryan04]

Re: What is this slight ticking in my engine?

Sounds good I'll run some of that through and see how we go, I'll keep you all posted, thanks for the responses! I have done many a successful repair with all your guys help, thanks.

 

[fr0zenpuck]

Re: What is this slight ticking in my engine?

I like your theory man....turn up the stereo, it could be allot worse!