3.7 mercruiser valve lash

[ericcarr2000]

Ok, I have been noticing that there seems to be a slight tapping noise coming from the valve cover. Can anyone give me some insight into re-lashing the valves? The motor is a remanufactured, blueprinted 3.7 merc that only has 99 hours on her...

 

[Don S]

Re: 3.7 mercruiser valve lash

Here is the procedure.

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

So they are adjusted with the lifters closed then...Got it, thanks Don.

 

[Don S]

Re: 3.7 mercruiser valve lash

They are CHECKED with the valve closed, not the lifter. Adjustment is done by changing pushrods.

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

All im really looking to do is to check the lash on the valves. theres a few that are just clicking a tad bit is all. Also, where can I get one of these lifter collapsing tools at, Ive checked all over town here?

 

[Eric 3.7LX Alpha 1]

Re: 3.7 mercruiser valve lash

You can check them Don posted the procedure, but you can't tighten the rocker nut more to adjust the lash...

They (the rocker nut) are already tightened down until they stop. Not like a Small Block Chevy engine.

I don't know about the tool, maybe someone else can help you to one

 

[artificialreef]

Re: 3.7 mercruiser valve lash

The collapsing tool is almost impossible to find. I got ahold of one (had to ship from australia)and bought an extra one. Works like a champ. You have to be very careful and patient with it. I bent all my pushrods torqueing on it. I think next time i would rig a balance on it and hang a gallon bucket of paint on it an let gravity do it overnight. Only other alternative is to pull all the lifters and bench bleed them but then you need the side plate gasket and intake manny gasket and more labor. Mine are all adjusted sweet now. The push rods have some cross-references with some easy cheap auto parts i will help you with once you get your lifters collapsed if you cant find merc. I fabbed my own feeler gauge after buying a micrometer. Just ground down some bar steel to the correct thickness. Go- no go gauge.

 

[artificialreef]

Re: 3.7 mercruiser valve lash

The bleed down tool does not come with the go-nogo gauge. Thats why i fabbed one. I bought an expensive 0 to 1 inch mike off the c-list, well it was expensive at one time. I paid 25$ and on my first trip to ace hardware saw a china knock off 0 to 1 inch mike for 19$ that will prob work just fine. Cut a piece of bar steel about 5 inches and grind one side to the go and the other side to the no-go. Its a little tricky to keep it uniform. You may end up screwing up a couple and you have to have a real light touch when you get close. Thats if you cant find that gauge. Or you could have a machine shop make one. I cant see them charging you more than 20$. It would prob be alot more accurate too. Just that i worked in a machine shop when i was a young punk and think i pulled it off.

 

[artificialreef]

Re: 3.7 mercruiser valve lash

Uhhm, before going through all that, any warranty. Why not have the rebuilder fix it?

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

Yeah, the warranty has since lapsed. It did have a year warranty on it....that was a year and a half ago.....And besides that, I ordered it online and installed it myself.....

Uhhm, before going through all that, any warranty. Why not have the rebuilder fix it?

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

So let me get this straight, once the rocker arm nut is torqued down all the way there really is no way of adjusting it at all? Shims could be used to adjust them though correct?

You can check them Don posted the procedure, but you can't tighten the rocker nut more to adjust the lash...

They (the rocker nut) are already tightened down until they stop. Not like a Small Block Chevy engine.

I don't know about the tool, maybe someone else can help you to one

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

They are CHECKED with the valve closed, not the lifter. Adjustment is done by changing pushrods.

Don, so to CHECK them all I have to do is make sure the valve is closed and then do the feeler gauge check then?

 

[Fishermark]

Re: 3.7 mercruiser valve lash

So let me get this straight, once the rocker arm nut is torqued down all the way there really is no way of adjusting it at all? Shims could be used to adjust them though correct?

It's been said a couple of times.... the only "adjustment" is with different push rods - not shims. The push rods come in different lengths.

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

I understand its been said a couple of times, but you must understand where im coming from. I have the rebuilder telling me I can get some shims to "adjust" them also. I know I can get different length push rods to do this adjustment. Im having problems trying to figure out on how to fabricate a lifter collapse tool now....lol....

It's been said a couple of times.... the only "adjustment" is with different push rods - not shims. The push rods come in different lengths.

 

[Don S]

Re: 3.7 mercruiser valve lash

I understand its been said a couple of times, but you must understand where im coming from. I have the rebuilder telling me I can get some shims to "adjust" them also. I know I can get different length push rods to do this adjustment. Im having problems trying to figure out on how to fabricate a lifter collapse tool now....lol....

Then get your "re-builder" to get you those shims, and then you can tell the rest of us about them.

Why isn't your engine re-builder taking care of this problem. If he rebuilt it properly, they shouldn't be loose and needing adjustment.
It could also be a faulty lifter. The pushrod only gets the lifter into a working range. The lifters internal working take care of the final range.
Kind of like how on a GM engine you turn the nut down 3/4 to 1 turn. It just puts the pushrod into a working range.

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

The reason he isn't taking care of the problem is because the warranty is up on the motor, it only had a year warranty on it. He had told me that you can "shim" under the pedestal mount to raise it up instead of having to put longer push rods in...
You mention that it could be a faulty lifter, that's kind of where I was leaning in the beginning...I guess I have to somehow fabricate a lifter compressor tool to be able to check these things....

Then get your "re-builder" to get you those shims, and then you can tell the rest of us about them.

Why isn't your engine re-builder taking care of this problem. If he rebuilt it properly, they shouldn't be loose and needing adjustment.
It could also be a faulty lifter. The pushrod only gets the lifter into a working range. The lifters internal working take care of the final range.
Kind of like how on a GM engine you turn the nut down 3/4 to 1 turn. It just puts the pushrod into a working range.

 

[stonyloam]

Re: 3.7 mercruiser valve lash

He had told me that you can "shim" under the pedestal mount to raise it up instead of having to put longer push rods in...

Hmmmmm seems to me that putting in a shim would be effectively the same as putting in a SHORTER pushrod wouldn't it?

 

[nola mike]

Re: 3.7 mercruiser valve lash

+1 with Terry. Which of course doesn't matter, since AFAIK those shims don't exist...and even if they did, that isn't any easier than replacing the pushrod.
Anywho, here ya go:
http://forums.iboats.com/mercruiser...drives/470-lifter-compressor-tool-469355.html

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

Ok, what im going to do is just replace all the lifters with new ones.....With these being new ones, will they be easier to compress down to be able to torque down the bolts?

 

[ericcarr2000]

Re: 3.7 mercruiser valve lash

+1 with Terry. Which of course doesn't matter, since AFAIK those shims don't exist...and even if they did, that isn't any easier than replacing the pushrod.
Anywho, here ya go:
http://forums.iboats.com/mercruiser...drives/470-lifter-compressor-tool-469355.html

Oh yes they do "exist" FYI...Ford Racing M 6529 A302 Ford Pedestal Rocker Arm Shims | eBay