Mercruiser 3.0 Valve Adjustment Video

Small video showing the procedure of adjusting the rockers arms on Mercruiser 3.0 engine. This will work on any Mercruiser engine as far as adjusting the arms but wont be in the same order...

[@markkennedy9264]

Best video ever explained properly give it a 10

[@hvn57me]

Man that was the best and greatest help for a guy who isn't rich and have a shop at 125.00 an hour do it. Already got ripped off for buying this boat so your ability to consider not everyone is a mechanic by going a step further I was able to do it myself. Thanks man!

[@CCPANHEAD]

Sharing which valves can be adjusted by cylinder and I or E is a huge time saver! Looks like a couple of people don't clearly understand how hydraulic lifters work, Thanks again.

[@Snacks3]

Wonderful! After searching forum after forum I found this great tutorial! I too recently purchased a vintage 1980 Rinkerbuilt with Mercruiser 3.0 and on our first outing, the valves started clanging. I'll post 2 videos responses showing my boat making the sound in case this would help anyone. Thans again!

[@jeremyrowe4339]

Thanks man, you cleared so much up for me. Mine is backfiring and will not start think its valves or distributor timing. Thanks man

[@bradc6985]

Aviation tech here, Great video thank you! On the water right now doing this adjustment without manual.

[@Speedy123youknowme]

Best help I have found even 12 years later all the marine mechanics over complicate it

[@gregmcmahan1745]

very nice video to help adjust the vales on 3.0

[@johnburkett7960]

This worked perfect!!! thanks

[@theunderthaker1726]

hey, arround 9min you talk about what is inlet and what is outlet. pretty easy. almoust every engine in the world turns clock wise. so if you turn youre engine over you'll see that the rocker arms from 1 cilinder move one by one. now if you follow the engine working cyclus( 1 inlet, 2 compression, 3 ignition, 4 exhaust) it means that the exhaust valve rocker always moves first and then the inlet valve rocker. kind regards. erwin

[@ryan95240]

Thanks it was a big help

[@jeremyrowe4339]

OMG thank you! The mercruiser book was so confusing!

[@manrod15]

Nice. Thank you for sharing.

[@chrissyn83]

great video i have just rebuilt a 3.0 my first rebuild. The only thing my manual says a full turn not 3/4 i have the mercruiser manual. I need to do this but dont have the remote start switch so i need to fig out how to rotate it with out the remote start but thanks it was a great vid

[@markhuffman64]

great video

[@mgrocki]

Hi. great video! i'm having trouble taking my valve cover off. I removed the 5 screws that held the cover on, but didnt take the plate that holds the shift cable off. Did you move this plate soley for that clearance issue and to "make room"? or is the plate doing a 2nd job and actually holding down the valve cover? Because my real issue that i ran into was this... after taking the 5 screws off, the valve cover didnt budge! I'm thinking its because the gasket is sticking/ "gluing" the cover down? i tried tapping the cover with a rubber mallet to loosen it up, but that didnt do anything. In your video, the valve cover came right out. If you have the time, let me know your thoughts, thanks!

[@samiam1150]

Another method is to find TDC for #1 and adjust those valves. Rotate the engine one full turn and adjust the next pair of valves in the firing order. Continue to rotate the engine one full turn and adjust the valves on the third cylinder in the firing order and one final revolution for the fourth cylinder in the firing order. In that way you don't have to know which valves are intake and which are exhaust. Works every time it's tried with no room for error.

[@dfb1111]

Exactly, that is how I do it also.

[@khalifahs371]

Good night pls explain better for me pls

[@dabbtime2897]

@@khalifahs371 this one fires in 1-3-4-2, so here the first cylinder is at Top dead center in firing mode. you can adjust both valves on the first cylinder. rotate the crank a full rotation and the 3rd cylinder is in firing order next because 1-3-4-2. adjust cylinder 3 valves. turn the crank again a full rotation for cylinder 4, adjust valves, turn the crank again full rotation and adjust the number 2 cylinder valves.

[@dabbtime2897]

another way of seeing which cylinder is going to fire is watch the valves. Turn the crank, look for the valves that won't move because they're staying shut for the combustion(firing). A million ways to skin a cat

[@dangbrewer1]

Thank you my brother

[@kamik306]

great video! thanks! :D

[@ArturSiewierski]

Great video! On a new lifter, are you able to squeeze them in when pushing on push rods? Mine are very hard to push but I've seen on cars that the lifters can be squeezed in by hand. Just want to know if I need to change them or not

[@victoryanda3538]

I am thinking of undertaking this job as the video explains it so well. I take it the spark plugs need to be removed before cranking to get oil going? Also how do I rotate 360° after adjusting first set of valves? I don't have external starter but would use key ignition. Thanks for advice.

[@TwoWheelRocco]

Great Job..

[@nort9889]

thanks a lot!

[@joseacd01]

Thank you

[@pierre-lucchiasson2508]

Parfait merci bcp 🤙

[@hakkitomanbay1019]

Thank you so much for the instructions! Extremely helpful and good video. I have been looking for the manual for this engine. Where did you get yours? any ideas? Thanks

[@vuch9208]

Thanks for this video! I have a 1994 Mercrusier 3.0 litre. My issue is that when the boat is cold it runs and sounds good. After 3-5 minutes at full throttle I get some popping. I'll back the throttle down to no wake, the popping goes away and I hear a ticking that lasts for about five minutes and then it goes away. If I throttle up again, the popping will come back repeating the cycle. The problem started with a sudden bogging down while pulling a tuber. I think I had bad gas with ethanol. I started using non ethanol fuel, put a can of seafoam with each 5 gallon can of non ethanol gas. I replaced the fuel filter at the base of the engine and cleaned the filter inside the carb. I replaced the spark plugs and by this time the bogging was gone but the popping was still there and then I noticed the ticking at no wake. I changed the ignition coil but the problem persists. I will change the distributor cap, rotor and spark plug wires tomorrow after getting them from the marina who had to order them. It that doesn't fix the problem, what should I address next? Thanks for your help!

[@codexic]

Timing is off or running lean

[@daveking4246]

I know a little late to help I'm sure you gotnit figured out by now but for future reference I've been told if it's bogging and popping 9 out of 10 it's electrical, look at points plugs wires and timing if it's just bogging it's fuel related carb filters fuel pump.....its held true every time I have a problem so far

[@russellk2341]

Hello i had to replace the timimg cover and it dosnt have the timimg mark tab so now what?

[@javierventeoruiz7700]

Hola saludos desde España, a cuántos grados de avance hay que poner el distribuidor gracias

[@stuartwood2677]

I have the same engine and have low compression on cylinder 3. Air is coming out of the carburetor. Could this procedure on cylinder 3 intake valve potentially fix my issue? 50 hour engine that sat in a barn 10+ years. Possibly cylinder 3 intake valve was open during that time and corrosion has set in. Thoughts?

[@AirBoone]

I Have a 91 GM 3.0 is the Valve Intake and Exhaust order the same? Ive read else where that is is IE EI IE EI , But not EI IE EI IE ? can you help??? I have no Compression now.. I belive that they are set to tight now... and possibly not in the correct valve order

[@davidvance8182]

My 3.0 makes that noise too. Did the rocker make the noise quit?

[@jimthao5466]

how do you wire the start engine button?

[@kerryholt7102]

1.E____1 - I_____2 2.I_____3 - E----------------360=4 3.E_____5 - I-----------------360=6 4.I_____7 - E----------------360=8 • Turn motor over to compression stroke, both number 1 and 2 valves closed, make sure crank notch is aligned to 0 on timing tab, proceed to adjust valves 1,2,3,5,7 Going from front of motor towards transom, start by spinning push rod and tighten rocker nut until valve lash is removed “push rod should barely spin rocker arm should not wiggle or have play= zero lash” After zero lash is reached proceed to tighten rocker nut additional ¾ turn • Turn motor 360 degrees, placed crank notch back to 0 on timing tab, proceed to adjust valves 4,6,8 to Zero lash, After zero lash is reached proceed to tighten rocker nut additional ¾ turn • For extra measure, spin motor another 360 and check for zero lash on valves 1,2,3,5,7, spin another 360 and check 4,6,8. I found that 2 of my lifters would leak down and cause the rocker arm to bounce around. Hints the engine noise I kept hearing. Also if your having trouble finding the compression stroke you can turn motor over until mark on crank notch lines up with "0" mark on timing tab, and engine is in No. 1 firing position. This may be determined by placing fingers on No. 1 valve as mark. If valves move as mark comes up to timing tab, engine is in No.4 firing position and should be turned over one more time to reach No. 1 position.

[@mar666cel]

thanks from the netherlands i did my valve just jet whit your perfect video but myn egine is a 1996 tks works the same why exsept for braket myn is on then valve cover ti self thanks !!!

[@iamvictorious1618]

I do not understand when you turn the engine 360 degrees after adjusting the valves as you showed, then what?????? Do I just start the engine?

[@nybdr657]

how do u set the distributor

[@hirvisgarcia5538]

Hydraulic diver loaded or unloaded?

[@dwaynebrewton9482]

Where did you find a online manual?

[@johnwagner9192]

Great Job! But there has to be a better way to do this other than by feel.

[@honeybees1970]

How do you change the fan belt without unbolting the engine

[@claymartin2000]

you cant

[@justinnoneyobidness4629]

Exactly

[@kimjensen3467]

It's possible 👌.. I did mine last year. You just have to push it down between the mount and the pulley, alternatively you can use a flat headed chisel and tap it down carefully, and you're good to go! 👌😊

[@farmgene]

Take off the support bracket for right engine mount, take off front pulley and turn pulley sideways while manipulating the belt through

[@JusTryNc]

If he adjusts them like that the valves will never close all the way you want a little play in the rocker arms

[@ThePCfreak2011]

Justin Gibson wrong

[@JCC1256]

I know this is old but anyway you could share your manual?

[@Snacks3]

Hmmmm... I'm not seeing my video responses.... maybe it takes a little while... You can always check my videos if you don't see them here.

[@RechStorm]

why can't you do all the rocker arms at the same time without rotating the engine 360? I didn't fully understand that

[@SUPAFLYGM3]

If you tighten them all up at the same time some of the valves will be in the wrong position when the piston comes up. You'll have a whole lot of other problems if that happens.

[@latunguley]

OK? What exactley does it mean when you inform us to rotate it 360 degrees? Am the only stupid one here?

[@bengyhernandez4792]

🤣🤣😂🤷‍♂️

[@justinnoneyobidness4629]

You have to get the other cylinders at top dead center to set valve clearance for that cylinder. All the cylinders arent at tdc at the same time hence why you need to rotate the engine to adjust the remaining rockers

[@marissacastaneda9492]

what up

[@markgeralds]

keep adj them valves you will be putting a cam in it the reason you hear valve tapping is the oil your running

[@markgeralds]

this video is so full of it if the nut had backed out that far the rocker arm would be off bs