Valve adjustment on a Mercruiser 3.7 aka 470

artificialreef

Chief Petty Officer
Joined
Feb 21, 2009
Messages
504
Hello again Friends. Things going great with my basket case purchase. Twin 470's no less. (didnt read these forums before i bought but got lucky and it has all the upgrades) Got both motors running (rehabed the impellars and replaced a flapper, had to drill out broken bolts on the exhaust in an impossible position) after rebuilding one carb, 2 complete tune up kits and fluid changes. They are both running cool. One has a loud tap that i am hoping for a valve adjustment. I know these are adjusted by changing the push rod lengths. My question is?

1. How do you know what size it came from the factory with?

I know when i purchase i will be aware of what they are and they are probably even labeled. But
I guess its maybe a stupid newb question, i could buy several sizes and start with the shortest but would like to know how you pros start off.
I know how to set the motor to check the correct valves.

question 2. Lets say the valve gap checks out. I will hope the tapping is not a connecting rod letting loose. Would a second possibility be a lifter beat to sh*t?


question 3 How hard is to change a lifter on one of these gems? I know rtm. Just a quick reply on this one would be cool.

Thank you for all your thoughtful assistance getting me this far.
 

Pete104

Lieutenant
Joined
Apr 30, 2011
Messages
1,439
Re: Valve adjustment on a Mercruiser 3.7 aka 470

You might have a casting plug, in the head, corroded thru that is making the "tappet" noise. Those big ford heads have a couple of them.
 

wrestling coach

Petty Officer 1st Class
Joined
Jun 27, 2011
Messages
210
Re: Valve adjustment on a Mercruiser 3.7 aka 470

You might have a casting plug, in the head, corroded thru that is making the "tappet" noise. Those big ford heads have a couple of them.

Pete,
Could you explain a little further.

Dennis
 

artificialreef

Chief Petty Officer
Joined
Feb 21, 2009
Messages
504
Re: Valve adjustment on a Mercruiser 3.7 aka 470

To clarify, question 1 and the rest were referring to the push rod length. You lost me Pete.
 

artificialreef

Chief Petty Officer
Joined
Feb 21, 2009
Messages
504
Re: Valve adjustment on a Mercruiser 3.7 aka 470

I finally found a lifter compression tool. Looking at the link stonyloam attached. Can anyone tell me what lengths the dyed and undied pushrods are? I will probably like to purchase several of the longest 2 since i think its a safe bet i wont need the shortest 2.
options are
no dye
red
blue
yellow
thank you for your help. I am very close to getting this planter wet.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Valve adjustment on a Mercruiser 3.7 aka 470

Here ya go, right out of the OEM service manual.

Untitled4.jpg
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
Re: Valve adjustment on a Mercruiser 3.7 aka 470

If you have the tool, I would put them in and check the lengths first, then buy pushrods if necessary. I think you can get them from your Ford dealer, would probably be less expensive.
 
Top