how to valve lash adjust merc 5.7

bolo78910

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i lent my manual out and stil didnt get it back , so i need a few info help from you guys,

on the rapido engine i have not hit wot as yet but so far it is kicking azzzz lol

only thing i notice is that the valves are rattiling and need adjustment.

i was told to take the valve cover of start with the # cilinder turn the crank ant both valves are close on at tdc, then adjust as to the roatation of the engine, or adjust one side first.

is there a way to adjust with the engine running?/ i know that is messy but i have a solution for that,

i now have the enging at about 3700 rpm lots of power, for a heavy boat carver montego 26 i am impress so far

thanks for any info
 

Don S

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Re: how to valve lash adjust merc 5.7

only thing i notice is that the valves are rattiling and need adjustment
.

Make very sure your oil level is not overful. To much oil will areate the oil and the lifters will start to collaps and they will be noisy.

What year is your engine, and I will post a link to the proper manual for your engine. Then, you will always have it.
 

bolo78910

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Re: how to valve lash adjust merc 5.7

don thanks i dont have the serial number at hand toight, but i think rapido said it was from 1987 to about 1991 0r 1992 u ask me for it a while back i posted it, but i dont know how to pull those past post.

at first the oil was a little over full i just change the oil two days ago and it is dead on .
 

bolo78910

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Re: how to valve lash adjust merc 5.7

don thanks , i have an up date here from day one when first start the engine i heard a small knocking sound from the engine, which i thought was the valve lash need adjust.

today the mechanic said it was not the valve , the knocking is coming from the internal of the engine, with the engine running he pulls one plug at a time to be sure one of the cilinder is not the fault,

the the knock seems to be on the port side. with the valve cover of i notice cilinder # 5 and # 7 those was spewing oil like a pipe, the rest was normal. is that a problem??

last i spoce to the builder who said maybe the crank is touching on something in the oil pan, your thought guy,

oil pressure is perfect,
 

bolo78910

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Re: how to valve lash adjust merc 5.7

just bumping this up a bit here guys.

sopose the wrong oil pan is install on this engine, would it cause that kind of lower end knock.
i reuse the old oil pan from the old engine, the pan has no rust or dent , but who knows it might be faulty, i need all the info i can get before i haul the boat and pull the oil pan off. engine has all the power in the world . oil presure is great. what the hell is going on. help here guys, i am almost broken hart like freeboytoney, just kidding,
 

J JACKSON

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Re: how to valve lash adjust merc 5.7

we used to have a oil pan on our race car that would hit the crank when ever we reinstalled it but as soon as it started it for the first time it would move the pan that fraction of a inch and it wouldn't hit again. i wouldn't think you would have that problem unless you are running after market rods or crankshaft. one thing you can try is removing the dip stick it could be hitting.
 

bolo78910

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Re: how to valve lash adjust merc 5.7

thanks this , engine sopose to have the extra horse power cam so who knows.

i just need some more info , rapido said he would replace it but i must make sure something is not hitting inside the oil pan, the engine also hav a heavy virbration even in nutral .
 

bolo78910

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Re: how to valve lash adjust merc 5.7

i am leaving on a fishing trip in boston tonight hopefull when i get back i might have some info on this thanks
 

Coors

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Re: how to valve lash adjust merc 5.7

Are the other rocker arms getting oil? besides the 2 ones you said?
 

bolo78910

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Re: how to valve lash adjust merc 5.7

there seems there are oil on both sides , but port side is flowing way way more oil, on idle number 5 and 7 cilinder are sewing oil about a 7,8,9, inches high. all the other cilinders on idle was not spewing but if i rev it a little oil will come out some but still not as hight as five and seven cil. should i check the the lifters again to make sure all is getting oil??
 

Don S

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Re: how to valve lash adjust merc 5.7

I think you need to contact the engine builder.
 

bolo78910

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Re: how to valve lash adjust merc 5.7

thanks don, i did contact him , he said to take out the plugs, make sure no water is in the cilinders, also to recharge oil system my pulling the ditributor and install the special tool an prime the engine again, dont know if that make sense, because i did all of that before i start the engine in the first place.

i am just disapointed right now
 

Coors

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Re: how to valve lash adjust merc 5.7

Sometimes, some rockers just dribble for a while, while others squirt; Tapping the squirters with a hammer, lowers the piston, in the lifter, and stops it for 30 seconds, maybe.
Then others start the squirt.
If oil pressure is ok, then trash in other lifters; push rods; gunky rocker arms.
They all should start random squirting. Re-priming won't help.
 

bolo78910

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Re: how to valve lash adjust merc 5.7

this is a newly rebuilt engine not even break in as yet, so i gess parts should be at least clean properly before install, as i am saying i am very upset right now, thanks for the coment guys. today i went back and adjust the rockers one more time, the engine dosent have that bad knock as before , took it out for a ride and it has all the power i can ask for, i just hope with some more hours on her it might work itself into a good runner.
 
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