The manuals can be misleading. I was aligning the pistons to the ignition position and tightened the lifters until they were stationary. After rotating them 270 degrees, I noticed through my precision gauge that the valve opened, even though it should have remained completely closed for proper compression. When the lifters stop moving, you need to rotate them between 60 and 90 degrees and then test the engine. Please correct me if I am wrong.
There is an easier way. I don’t follow the manuals, I chase the firing order and adjust both valves on a cylinder when it’s at TDC on compression stroke. I did a video on the method.
For lifters there are assembly lubes that are supposed to help with cam break in. On new lifters I use these break in lubes. On the 3.0 for new cam and lifters do not idle the engine low when first starting. Get it running and keep the idle 1800-2000 rpm. This helps unload the very tips of the cam lobes using the momentum of the lifter.
I did another video on how I adjust valves. I only used the method in this video because the manual explains it this way. I think my way is much better and faster. Mercruiser 3.0 3(c) - Easier Way To Adjust Valves!! ua-cam.com/video/1A7mteNPCxc/v-deo.html
@@Molly-hk2rk there is no point in soaking lifters in oil. All it does is make a mess. Since the 3.0 is a flat tappet camshaft you do need to use assemble lube on the lifter face and can lobe when installing lifters. Just put a few drops of oil all around the lifter body and assembly lube and install the lifter. Without oil pressure around the lifter oil will not enter the lifter body even if they are soaked in oil. When you prime the engine with with a drill it will fill the lifters with oil at that time. Also do not run the engine at idle during first run. It needs to run 1500-2000 rpm for 20 minutes to break in the camshaft. This is critical to having the camshaft last.
Great Video! Do I use a sealant on the head gasket, or install the gasket dry? The Seloc manual says to apply perfect seal to both sides of the gasket, but the Mahle head gasket kit says the head gasket is designed to be installed dry, unless recommended by the manufacturer. The kit (HS5719W) includes a packet of JV7 aluminum silicone sealant. thanks for your advice! Keep up the videos!
I’m at top dead center on a 99 Bayliner with 3.0 merc and #4 rocker arms are moving-not the front rockers like in your video…where do I start?? Thank you
Nevermind. I’m a dummy. I need to rotate the engine until it’s tdc on #1. Trying to figure out how to do that as the engine is in the boat and front motor mount has crank/harmonic balancer inaccessible and can’t use the belt because alternator belt tensioner bolts to exhaust manifold which is off 🙄
I labeled the rods as they came out but do I have to spin the motor to adjust? Can I just run down the nut til rod doesn’t spin plus 3/4 turn all in one shot? I didn’t move the shaft since I took it apart, can I tighten all 8 and call it good?
No, You can only adjust valves when that cylinders piston is rising or falling to/from Top Dead Center in a 180 degree window around the firing stroke. Any other time the valves are being moved by the camshaft and there will be no play in the valve. The point of adjusting valves is to remove the “play” when the valves are at rest. You need to watch my video on adjusting valves by chasing the firing order. Watch this video: ua-cam.com/video/1A7mteNPCxc/v-deo.html
The mercruiser manual (not clymer) literally says to torque these to 22 ft lb. But it never gets there. I had to tighten them based on when I started losing compression in the cylinder, but when I achieved max compression, the rockers seemed a little too loose. And I swear I can hear them slapping around when running engine. What does this mean?
That’s because you’re looking at the wrong page in the Mercruiser manual. Page 3A-18 of the factory 3.0 manual explains how to adjust valves with the engine not running and it’s exactly how I’ve shown in the commented video. Page 3A-25 (same manual) says to torque them down to 20 ft. lbs. If you do this you’ll cause the valve to open permanently and engine won’t run and it’s possible you could pull the rocker arm stud partially out of the head. You’ve discovered one of the numerous errors in these manuals. You have to use prior experience and judgement when using the Mercruiser manuals to rebuild these engines. They are full of errors. The errors I encounter the most are in the engine specs for clearances. They move decimal points around a lot and get service and production clearances mixed up a lot too. This comment has inspired me to do a video about this issue.
The rings on a piston start about 1/4” below the top. Since the rings are doing most of the wear a ridge will form 1/4” below the top of the bore on a used engine. With the piston down in the bore, if you can feel a ridge with a finger nail or feeler gauge the bore is worn. As a matter of fact if the ridge is very pronounced you have to use a ridge reamer to get the pistons out.
Thank you for your video! One question that i have is, after i did everything you said and did the 3/4 move. Some of them were still lose, i could kind of rotate them when i turned around the engine once, so what i did was i tightend them again and did another 3/4 on them. Is it ok to do so or do i have to readjust them again?
I would do it again. The three-quarter turn is supposed to put the lifter in its 50% preloaded condition. If you turn it another, you just took all the play out of it. The spinning pushrod method isn’t always foolproof. Sometimes it’s hard to tell when there’s drag on it. In those situation‘s, I look at the lifter and watch for movement of the plunger. As soon as I see any movement at all that’s when I know the lash is zero and I can then turn three-quarter turn.
@@moccasinmarine Update, i did it exactly like you said, worked perfectly after 30 seconds of starting. One question: can i remove the golden filter that is in the carborator?
Either buy new or just run them anyway. The pushrods are not really a concern. The lifters are the serious issue with this type camshaft. If you mix up used lifters the engine won’t last.
@@alexpaun3153 if you mixed up lifters then definitely you need new lifters. I have a video showing pushrods spinning as engine runs. The lifters are supposed to spin to wear evenly. If not they’ll wear at one spot and not last long.
Yes you don’t torque them down. The nuts are friction nuts. They won’t back off on their own. You remove the play (you can’t always tell play from rotating pushrod; any change in pushrod twist tension is a sign play is out; they sometimes still rotate easily) and then turn 3/4 turn more (1 turn on V8s).
@@moccasinmarine Very important detail, I noticed that the instructions from the book can be confusing. Just because after the play has been removed doesn't mean that you can't spin the push rod with a little more effort. I was reading it before as if you had to absolutely take out all the ability to spin the rod which would actually cause it to be too tight.
If you are referring to the pushrods it’s not critical that they go back in the same hole. What is critical is the lifters that ride on the camshaft. If you reuse the camshaft the lifters must go back on the same camshaft lobe. The cam and lifters form a wear pattern from rubbing together for years and once that wear pattern is established the parts must be assembled in the same location they were removed from. The pushrods aren’t as critical but I still put them back in the same location as well.
Nice Job! Thank you for your time.
He never posted the link for the manual
The manuals can be misleading. I was aligning the pistons to the ignition position and tightened the lifters until they were stationary. After rotating them 270 degrees, I noticed through my precision gauge that the valve opened, even though it should have remained completely closed for proper compression. When the lifters stop moving, you need to rotate them between 60 and 90 degrees and then test the engine. Please correct me if I am wrong.
There is an easier way. I don’t follow the manuals, I chase the firing order and adjust both valves on a cylinder when it’s at TDC on compression stroke. I did a video on the method.
Great video buddy. Oil wise what do you do with lifters? I’ve rebuilt my boat engine using your channel
For lifters there are assembly lubes that are supposed to help with cam break in. On new lifters I use these break in lubes. On the 3.0 for new cam and lifters do not idle the engine low when first starting. Get it running and keep the idle 1800-2000 rpm. This helps unload the very tips of the cam lobes using the momentum of the lifter.
Great video thanks for the info!
I did another video on how I adjust valves. I only used the method in this video because the manual explains it this way. I think my way is much better and faster.
Mercruiser 3.0 3(c) - Easier Way To Adjust Valves!!
ua-cam.com/video/1A7mteNPCxc/v-deo.html
@moccasinmarine I have brand new lifters to install and set the rockers In a motor I just had rebuilt. Do I presoak the lifters in oil?
@@Molly-hk2rk there is no point in soaking lifters in oil. All it does is make a mess. Since the 3.0 is a flat tappet camshaft you do need to use assemble lube on the lifter face and can lobe when installing lifters. Just put a few drops of oil all around the lifter body and assembly lube and install the lifter. Without oil pressure around the lifter oil will not enter the lifter body even if they are soaked in oil. When you prime the engine with with a drill it will fill the lifters with oil at that time. Also do not run the engine at idle during first run. It needs to run 1500-2000 rpm for 20 minutes to break in the camshaft. This is critical to having the camshaft last.
Great Video! Do I use a sealant on the head gasket, or install the gasket dry? The Seloc manual says to apply perfect seal to both sides of the gasket, but the Mahle head gasket kit says the head gasket is designed to be installed dry, unless recommended by the manufacturer. The kit (HS5719W) includes a packet of JV7 aluminum silicone sealant. thanks for your advice! Keep up the videos!
Install head gasket dry. Modern gaskets have a coating from factory
How did you arrive at tightening the rockers down before your adjustment??
Not sure I understand your question.
thank you for the video.
I’m at top dead center on a 99 Bayliner with 3.0 merc and #4 rocker arms are moving-not the front rockers like in your video…where do I start?? Thank you
I don’t know if it’s number 4 but it’s at the opposite end of the block than the front (closest to the water pump).
Nevermind. I’m a dummy. I need to rotate the engine until it’s tdc on #1. Trying to figure out how to do that as the engine is in the boat and front motor mount has crank/harmonic balancer inaccessible and can’t use the belt because alternator belt tensioner bolts to exhaust manifold which is off 🙄
Your only option is to bump the engine with the starter to get it to TDC on #1
I labeled the rods as they came out but do I have to spin the motor to adjust? Can I just run down the nut til rod doesn’t spin plus 3/4 turn all in one shot? I didn’t move the shaft since I took it apart, can I tighten all 8 and call it good?
No, You can only adjust valves when that cylinders piston is rising or falling to/from Top Dead Center in a 180 degree window around the firing stroke. Any other time the valves are being moved by the camshaft and there will be no play in the valve. The point of adjusting valves is to remove the “play” when the valves are at rest. You need to watch my video on adjusting valves by chasing the firing order. Watch this video:
ua-cam.com/video/1A7mteNPCxc/v-deo.html
hello mate, can i use this procedure to adjust Valves in a s10 2.5 iron duke?
You would be better off using this universal method.
ua-cam.com/video/1A7mteNPCxc/v-deo.html
The mercruiser manual (not clymer) literally says to torque these to 22 ft lb. But it never gets there. I had to tighten them based on when I started losing compression in the cylinder, but when I achieved max compression, the rockers seemed a little too loose. And I swear I can hear them slapping around when running engine. What does this mean?
That’s because you’re looking at the wrong page in the Mercruiser manual. Page 3A-18 of the factory 3.0 manual explains how to adjust valves with the engine not running and it’s exactly how I’ve shown in the commented video. Page 3A-25 (same manual) says to torque them down to 20 ft. lbs. If you do this you’ll cause the valve to open permanently and engine won’t run and it’s possible you could pull the rocker arm stud partially out of the head. You’ve discovered one of the numerous errors in these manuals. You have to use prior experience and judgement when using the Mercruiser manuals to rebuild these engines. They are full of errors. The errors I encounter the most are in the engine specs for clearances. They move decimal points around a lot and get service and production clearances mixed up a lot too. This comment has inspired me to do a video about this issue.
@@moccasinmarine lucky for me, I didn't push it that far. 😅
what is bolt and thread size you used for turning crank ?
3/8 of an inch fine thread. The bolts are in the harmonic bouncer not the crankshaft. The crankshaft does not have a hole in the center.
How do I know if a cylinder walls to far gone to be ok
The rings on a piston start about 1/4” below the top. Since the rings are doing most of the wear a ridge will form 1/4” below the top of the bore on a used engine. With the piston down in the bore, if you can feel a ridge with a finger nail or feeler gauge the bore is worn. As a matter of fact if the ridge is very pronounced you have to use a ridge reamer to get the pistons out.
What size where those bolts you used to turn the engine
3/8” fine thread. 3 come with a harmonic balancer removal tool.
Thank you for your video! One question that i have is, after i did everything you said and did the 3/4 move. Some of them were still lose, i could kind of rotate them when i turned around the engine once, so what i did was i tightend them again and did another 3/4 on them. Is it ok to do so or do i have to readjust them again?
I would do it again. The three-quarter turn is supposed to put the lifter in its 50% preloaded condition. If you turn it another, you just took all the play out of it. The spinning pushrod method isn’t always foolproof. Sometimes it’s hard to tell when there’s drag on it. In those situation‘s, I look at the lifter and watch for movement of the plunger. As soon as I see any movement at all that’s when I know the lash is zero and I can then turn three-quarter turn.
@@moccasinmarine Thank you for the fast response! will do it again.
@@moccasinmarine Update, i did it exactly like you said, worked perfectly after 30 seconds of starting.
One question: can i remove the golden filter that is in the carborator?
@@pooyayousefi582 filters are there for a purpose. You might could run it for a short time without a filter but I would replace it soon
@@moccasinmarine Thank you kindly for the info! I bought a new one.
If I mixed the push rods , what can I do now to fit them correctly?
Either buy new or just run them anyway. The pushrods are not really a concern. The lifters are the serious issue with this type camshaft. If you mix up used lifters the engine won’t last.
@@moccasinmarine so new rods and new lifters ideally.
@@moccasinmarine so new rods and new lifters ideally.
@@alexpaun3153 if you mixed up lifters then definitely you need new lifters. I have a video showing pushrods spinning as engine runs. The lifters are supposed to spin to wear evenly. If not they’ll wear at one spot and not last long.
@@moccasinmarine block is not stripped . I only removed the top of the engine at this moment. Can I contact you for some private help ?
So, there is no need for a torque wrench when doing the valve adjustment? Just tighten to remove lash, then 3/4 turn?
Yes you don’t torque them down. The nuts are friction nuts. They won’t back off on their own. You remove the play (you can’t always tell play from rotating pushrod; any change in pushrod twist tension is a sign play is out; they sometimes still rotate easily) and then turn 3/4 turn more (1 turn on V8s).
@@moccasinmarine Very important detail, I noticed that the instructions from the book can be confusing. Just because after the play has been removed doesn't mean that you can't spin the push rod with a little more effort. I was reading it before as if you had to absolutely take out all the ability to spin the rod which would actually cause it to be too tight.
Io ne ho due che i meccanici della zona non riescono a farli andare😢😢😢
I don’t know your language. What language is this and I’ll translate.
Well I pulled the rods not knowing they had to go back to the same place 🤦🏻♂️
If you are referring to the pushrods it’s not critical that they go back in the same hole. What is critical is the lifters that ride on the camshaft. If you reuse the camshaft the lifters must go back on the same camshaft lobe. The cam and lifters form a wear pattern from rubbing together for years and once that wear pattern is established the parts must be assembled in the same location they were removed from. The pushrods aren’t as critical but I still put them back in the same location as well.
What do I do if I didn't number the lifters or rods
@@clarencevela-vm9wlif you can’t make a very good guess, then you’ll need a new camshaft and new lifters.