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mercruiser 470 new lifters question?

S

Skylar

Member
I have a question about the mercruiser 470 lifters. I cant find the collapse tool to collapse the lifters fully down before setting the valves . My question is if I where to but new lifters would they all ready be collapsed this is probably a dump question but I was wondering ? And also would the new lifters have to go in a specific order?
 
When they refer to collapsed in the torque instructions they typically mean...........

While you tighten down the rocker arm nut, you spin the push rod gently, As you continue to tighten (before torquing) The oil will be forced out and then the plunger spring will need to be collapsed also. If the lifter is full of oil this can take up to 20 minutes or more for all the oil to be forced out. Also it can take less.

So continuing to tighten the nut while spinning the rod and at some pint the rod will or should become more difficult to spin but should still spin.

Also make sure everything is oiled up. DO NOT DO THIS DRY!!

Due to the design of the 470/Ford big block head, you can only tighten the rocker arm nut so much and once that occurs it should be bottomed out. (push rod length is specific) so if you have the rods in the correct locations you should be ok.

Now simply torque to spec.
 
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you torque everything down first having each piston at TDC compression, then collapse the lifter fully to measure the gap, then pick the correct length pushrod
 
I am saying if you use all the original parts, A new exact replacement OEM head gasket and the head has not been milled to flatten then and all the same push rods then No special tools.

If any of the push rods have been replaced they must be matched in length or you will need the special tool to adjust the gap.

If the head was milled and say .020" was removed to flatten it then you need the tool or a tool with the same dimension to set the gap.

If the head gasket is not OEM specified (thinner or thicker) the you will need to set the gap.
 
Skylar, technically these are hydraulic "Cam Followers" (aka "lifter" in an old and misnomer fashion).

Regardless of engine make, the adjustment is made to effectively set the cam follow "plunger" depth...... (it is not actually a valve adjustment, per 'se!)

The goal is to set the hydraulic "plunger" to a near "half travel" depth while the Exh or Int valve is fully closed.
This gives the plunger some compensative value!
IOW..... this gives the cam follower an ability to "self adjust" (these were originally referred to as "self adjusting" tappets in the early automotive years).

What is being described as "collapsed" is indeed the plunger being "bottomed out".
There is a check valve and a mild spring underneath each cam follower plunger.
In order to bring the plunger to the bottom of it's travel, the hydraulic oil cushion must be relieved.
(as Jack explained... this can require some time.)

In answer to your question.... Yes, brand new cam followers would be easier to deal with as they would only be lightly lubricated!

While the cam follower plunger is in this bottomed out position, the prescribed "gap" between the valve stem and rocker arm tip is to insure that the actual plunger depth has been achieved.

This is a little bit different procedure than what we would use for a more conventional Gasoline Marine Engine adjustment...... such as a GM SBC.

If you will follow the procedure spelled out by Bt Doctur, you can't go wrong!



.
 
most start with the exaust valve ,then 2 intake valves, then 2 exaust valves, then 2 intake valve, and then 1 exaust valve

Consider that once the intake opens and closes that cylinder is on its compression stroke with both valves closed.
Simply rotate the motor untill an intake opens and closes , and adjust that cylinder and move on to the next cylinder the same way.
 
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Well what I ment was how do I know what valves are which the diagram doesn't show
What valves are what like intake... exaust ....which is.valve 1 intake....2 exhaust I don't know where to start lol sorry for the noob questions I know how to turn a wrench lol its just valves get the best of me
 
Going from left to right exaust, intake, exaust, intake, exaust ,intake, exaust , intake
Going left to right #1,#2, #3, #4
 
Skylar said:
Well what I ment was how do I know what valves are which the diagram doesn't show
What valves are what like intake... exaust ....which is.valve 1 intake....2 exhaust I don't know where to start lol sorry for the noob questions I know how to turn a wrench lol its just valves get the best of me
Click to expand...

Based on this response I would suggest finding someone who knows more than just being able to turn a wrench....have that person teach you what to do in person instead of trying to learn from a forum post. This is something that requires specific training or extensive experience. You should not attemp this alone if you cannot identify an intake valve vs a exhaust valve. What you are asking is basic engine 101.....sounds like you dont have this....
Not trying to be mean here but i think you need assistance from someone in person.

Also try youtube...
 
Well now i understand the way btdoctor explained it it would go like this from left to right
#1 exhaust # 2 intake #3 exhaust # 4 intake #5 exhaust # 6 intake # 7 exhaust # 8 intake it would go in that order from left to right is that correct?
 
Well now i understand the way btdoctor explained it it would go like this from left to right
#1 exhaust # 2 intake #3 exhaust # 4 intake #5 exhaust # 6 intake # 7 exhaust # 8 intake it would go in that order from left to right is that correct?
 
I have one more question if I have a cylinder head that has a 4 barrel intake and a 2 barrel intake are the bolt-holes the same pattern and will it work my question is are the intakes different
 
I am saying if you use all the original parts, A new exact replacement OEM head gasket and the head has not been milled to flatten then and all the same push rods then No special tools.
 
Skylar said:
I have one more question if I have a cylinder head that has a 4 barrel intake and a 2 barrel intake are the bolt-holes the same pattern and will it work my question is are the intakes different
Click to expand...

Same holes, a 2 or 4 barrel intake will bolt up to the head
 
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