4.3 lifter/rocker clicking sound

Howdy all! I have a 1990 Rinker V190 in excellent condition. The motor runs great, uses no oil and is otherwise in fine shape as well. My only curiosity relates to a faint lifter/rocker arm "clickity" sound. It's on both banks and is not isolated to any particular cylinder. It's a sound that I would imagine coming from a solid lifter motor, but I'm presuming the 4.3 Mercruiser has hydraulic lifters. It's not a big concern. I'm just curious whether this is typical. I'm not the original owner and don't have much history except to say that the engine is immaculate and runs great.

I would suggest you get a Automotive Stethoscope and try to pin point the clicking sound.

Many times, the exhaust flappers loose the rubber edge piece and hit the exhaust down tubes and create a clicking sound which can easily be confused for a lifter noise.

Click on link and look at item 6

It may or mat not be your issue but if it is, it is an easy fix..........Replace them (there is one on each side even though the image shows only one)

https://www.marineengine.com/parts/.../exhaust-system-use-with-4-inch-exhaust-elbow

kghost said:

I would suggest you get a Automotive Stethoscope and try to pin point the clicking sound.

Many times, the exhaust flappers loose the rubber edge piece and hit the exhaust down tubes and create a clicking sound which can easily be confused for a lifter noise.

Click on link and look at item 6

It may or mat not be your issue but if it is, it is an easy fix..........Replace them (there is one on each side even though the image shows only one)

https://www.marineengine.com/parts/.../exhaust-system-use-with-4-inch-exhaust-elbow



View attachment 28398

Click to expand...

Thank you. I will take a look. To the extent that the "flappers" are in need of repair, is there reason for immediate concern and/or damage to the engine?

I also may wind up pulling the valve covers to see what's lurking beneath.

As it turns out upon further inspection, I'm pretty sure the "clicking" sound is coming from the rocker arms under the valve covers. So my original question is in search of and answer. Is some rocker arm clicking typical on the Mercruiser 4.3, particularly if the motor is older (not sure)...OR is it supposed to be oh so quiet in that area? As previously mentioned, the sound is across both banks. No particular single cylinder.

A "little" clicking is NOT normal. All things being good it should be virtually silent

What is your oil pressure? Should be around 40 psi

What oil are you using? What weight? 30w 40w 20-40w......What?

If this clicking has been with the engine since you purchased the boat it is possible the engine may have had some work done to it over the past 20ish years before you bought it. If any head work was done then the rocker arm nut(s) may have been marginally adjusted or possibly loosened.

Do as you suggested and remove one valve cover at a time and put some shop rags at exhaust manifold and head area to absorb oil and start engine, Listen and see if you can pin point the clicking rocker/noise. Carefully observe all the rocker arms looking for any one that may not be moving the same amount as the rest.
Maybe take a video with you phone and post it so we can see and hear.

If you can pin point the noisy rocker arm, tighten the nut 1/8 of a turn and see if it goes away.

If it does not, go 1/8 of a turn more but no more that 1/4 turn in total. If it still does not go away then you may have weak valve spring or a bad lifter-which will require the removal of the intake manifold to access the lifter valley and a lot more work.



Remember, the OEM (STATIC) method is tighten rocker arm nut until push rod just starts to feel resistance while spinning by fingers (Engine NOT running and no intake manifold installed) then tighten nut 1 full turn from that point and you are done. This is done for all 12 rocker arms, Intake and exhaust. This technically puts the lifer plunger in the middle of its travel in the lifter. So you do have some adjust ability, less then or more than the OEM specification. NOTE: there is a well written procedure that must be followed when doing a static adjustment as i described. The engine has to be rotated per instructions in the procedure so you adjust them when appropriate. You cannot simply adjust them all at the same time when doing it statically (Engine not running)

You can also adjust each rocker arm when engine is running, you start with one rocker arm, loosen it until you hear clacking and stop loosening. Then start to tighten slowly until clacking goes away. Once it is gone you tighten 1/4 turn and let engine run for about 60 seconds, then adjust 1/4 turn again and wait again for 60 seconds for engine to recover. Many people only go the total of 1/2 turn but it is OK to go 3/4 to 1 full turn (tightening of rocker nut). Myself and a few others try to go a total of 1/2 to 3/4 turns form zero clacking when running.
You will repeat this for all 12 rocker arms so all are adjusted the same.. It is a messy process adjusting when engine is running as the oil wants to run out of head and onto and down the exhaust manifold.

Try either process and report back.