Logo
FULL SITE MENU

Valve train noise 318

M

mattv

Contributing Member
Hey guys,

I have noticed on my starboard engine that when I first start it for the day you can hear a loud clacking from the valve train until it builds oil pressure. Any ideas?

Thanks,

Matt
 
unfortunately, the 318 does not have adjustable valves. the noise can be caused by a weak lifter, or a cam lobe that is stating to wear. replacing the lifters is a very easy on the 318 and can be done easily with basic hand tools in a couple of hours. make sure you are not confusining valve rattle with rod knock.......
 
All,

Thanks for the replies, fresh oil and filters the day before I posted this. It has been going on for a while now and definetly goes away once the pressure is up. It happened last year and changing the oil made it stop... For a while anyway
 
Mine does that as well. The important thing is to avoid reving the motor before the noise goes away.

Jeff

PS: If you drop in a set of new lifters, be sure to use the correct break in lube on them, and be prepared to let the motor high idle (2,000 rpms) for several minutes at start up (or the new lifters will fail, taking the cam lobe with them).
 
I too have lots of lifter noise. I mixed up a batch of engine "cleaner" by adding some ATF and Marvel to the oil. Ran this for a while with a new filter to clean and then changed the oil and replaced a qt with Marvel. Works well, much quieter. I have never been a big believer in additives but it seems to help in this case. Lots of oil/filter changes with high detergents to clean. Helps.
 
Most of the above Plus maybe pull a tappet cover on that cyl bank & measure total valve or pushrod travel at full lift compaired to the others...if it settles after a few seconds its probably tired lifter internals ... this is confirmed with your comment : "went away after earlier fresh oil changes but comes back)
If not too keen on delving further with more costs Add Some RESTORE engine additive along with Can of STP with 30-40 Pennzoil
A lash cap temporarily fitted to soft lifter valve top might lessen noise quicker on start-up & if so points more towards a Cam lobe wearing beyond toterance along with High bleed-down lifter

Whats the engines total hours ?

Cheers
Tara2
NZ
 
Most of the above Plus maybe pull a tappet cover on that cyl bank & measure total valve or pushrod travel at full lift compaired to the others...if it settles after a few seconds its probably tired lifter internals ... this is confirmed with your comment : "went away after earlier fresh oil changes but comes back)
If not too keen on delving further with more costs Add Some RESTORE engine additive along with Can of STP with 30-40 Pennzoil
A lash cap temporarily fitted to soft lifter valve top might lessen noise quicker on start-up & if so points more towards a Cam lobe wearing beyond toterance along with High bleed-down lifter

Whats the engines total hours ?

Cheers
Tara2
NZ
 
I had the same noise. I removed the covers and cranked down on all (I believe it's 5) bolts that hold down the rocker assembly. The specs are 30fp. But that was not tight enough. Tighten as tight as u can (without breaking the bolt). Then change the oil. Mine quieted down right away! But I still get a little clatter during warm up, then it goes away when shes warm. Like Jeff said take it easy on her when she's cold, and keep changing that oil. What oil? That's a whole other thread!!!
 
I will give that a shot but it normally does quite down as soon as the oil pressure comes up. I have in the past been using delo 30w but recently switched to rotella 15/40w I have not been able to get to the boat in weeks due to work and family stuff... Have not even taken her out since march and that was for a haul out, if you can't tell I'm depressed over it. Thanks for the advice I will get back to you with the results
 
Back
Top