lifter issue and rock arm registration

[ste80]

good afternoon all; i need your kind support please. in this days i installed my motor heads and i was in about to install valves lifter and i had a big issue.
on manual #18 ( mine is 4.3 lx 1995) and here in the forum i sow that for my model ( with balancer shaft ) i don't have to perform the 0 clerenace on push roads +3/4 of rotation for valves registration but as per manual roket arm need to be closed at right torque ( 27 nm) .

after installation i torque the roket arm at 27 nm but i sow that after one complete revolution valves was opening ( the push roads was not loading the lifter but was bloked so the valves opened as consequence)
i removed the lifter and i sow that i could not push the lifter down.
i disassembled all the lifter and i cleaned in ultrasonic device.




after that installed back the lifter with no oil i can push the spring properlly so i assueme that now i can tight the roket arms at 27 nm without issue ( but i can push quite easyly)

i did also a test, i open again one lifter, i put some small amount of oil inside the lifter before assembling and try again with same resoult of before cleaning ( no compression allowed due to oil )

accordingllhy to what i understud the inside part of the lifter has a no return valves. when motor is on, pressure goes on and oil goes inside the lifter, and gose trought the no returne valves and get the lfter hard just allowing same small movement ( 0,1 mm) to allow thermal compensation.

i need to understand, how i should proceed ? shell i install all lifter totally empty as now tight 27 nm the roket arm and switch on the motor? how the lifter will be filled by oil? i left them on motor oil for 2 days but without pressure the not return valves can not open so oil will not fill them inside.

sorry for long message, i hope i could explain it properlly but which one is the right methid to install this?

ps ( i have installed EFI cams )

 

[alldodge]

Did you rebuild the lifters, as in replacing the seals inside?

If not they could still be ok but would have to run the motor to find out. The lifter needs to be full of oil and I usually place them in a container and let soak in oil overnight.

 

[ste80]

Did you rebuild the lifters, as in replacing the seals inside?

If not they could still be ok but would have to run the motor to find out. The lifter needs to be full of oil and I usually place them in a container and let soak in oil overnight.

Thanks.
I didn't remove the non return valves. I think the seal is there right? is an OR? I still have them outside but i'm woRried that size is in inch and i will not find them here in italy . Do you know size?

I left in a tank of oil for 2 days now but oil will not go over the not return valves (i open one today to check after one full day in oil and oil was not oil where the big spring is (i think you need motor oil pressure tu open the not return valves)
Is that ok? What happen when you switch on motor? Valve nois for some time just to put lifter in pressure? Or ther is another way to do?
Thanks for the help

 

[Lou C]

OK I don't want to add more confusion here but on these engines besides all the other changes like no balance shaft/balance shaft, and pre-Vortec/Vortec heads, there is also this:
adjustable valve train
net lash valve train (non adjustable)
I'm not sure what year they changed from adjustable to non-adjustable but my old 1988 has the adjustable set up where you find zero lash and then go one turn more (GM's specs, some use 3/4 turn).
Make sure you know which system you have first before doing anything.
Here's what the adjustable valve train looks like:
and the non adjustable valve train:
notice that the design of the rocker arm is totally different than the old system....


so post up some pix of your rocker arms so we can see what you have
Mixing and matching on these 4.3s can get very confusing which is why I left mine exactly as it was built, even though I could have picked up some HP by using the Vortec heads.

 

[Lou C]

And from what I was able to find, of the 2 plants making 4.3s, the Tonawanda NY plant (this is where the industrial and marine engines came from) switched to the net lash system in '92, whereas the Romulus Mi. plant didn't switch till '95, and when the change was made, the base circle was changed to 1.260" on all of the cams and a lifter with more travel was used across the board, apparently to provide more latitude for manufacturing tolerances with the "net lash" rockers.
So it's important to know what you have! One way to tell is in addition to the block casting # that is on the bell housing area, the front of the block right where the starboard side head meets the block, has a GM serial #. This will start with a T for Tonawanda or an R for Romulus.

 

[ste80]

OK I don't want to add more confusion here but on these engines besides all the other changes like no balance shaft/balance shaft, and pre-Vortec/Vortec heads, there is also this:
adjustable valve train
net lash valve train (non adjustable)
I'm not sure what year they changed from adjustable to non-adjustable but my old 1988 has the adjustable set up where you find zero lash and then go one turn more (GM's specs, some use 3/4 turn).
Make sure you know which system you have first before doing anything.
Here's what the adjustable valve train looks like:View attachment 405855
and the non adjustable valve train:
notice that the design of the rocker arm is totally different than the old system....
View attachment 405856

so post up some pix of your rocker arms so we can see what you have
Mixing and matching on these 4.3s can get very confusing which is why I left mine exactly as it was built, even though I could have picked up some HP by using the Vortec heads.

Thanks lou as usual for your nice support.
For the roket arm, i would say that it is like your first Picture but i would say that if i look onto manual 18 on first page thay sayd that that manual is for some sn and mine is there. So theorically manual #18 is for my serial n.

Said that i sow here in the forum one Thread were one guys was askin one similar question , he was saying: i did 0 lash, + 3/4 but tourque is too low why? And one replay was: on this motor with shaft balancer you dont have to do 0 lash + 3/4 but torque value.

When i did the mechanical works the mechanic told me same 0 lash+ 3/4 turn but trust me no torque is there so i'm really worry of this.

This is the picture

 

[ste80]

And from what I was able to find, of the 2 plants making 4.3s, the Tonawanda NY plant (this is where the industrial and marine engines came from) switched to the net lash system in '92, whereas the Romulus Mi. plant didn't switch till '95, and when the change was made, the base circle was changed to 1.260" on all of the cams and a lifter with more travel was used across the board, apparently to provide more latitude for manufacturing tolerances with the "net lash" rockers.
So it's important to know what you have! One way to tell is in addition to the block casting # that is on the bell housing area, the front of the block right where the starboard side head meets the block, has a GM serial #. This will start with a T for Tonawanda or an R for Romulus.
View attachment 405857

This is my gm block casting, my head is 181 final

 

[Bondo]

Ayuh,.... Are you doing this with each cylinder turned to Tdc,..??

 

[alldodge]

Cleaning the lifters I'll assume they were not marked so they didn't go back in same hole and same facing position?

All the rocker nuts should go down the same amount. The ones not fully seated need to find out why. Take the lifter back out and check to see if it goes all the way down when pushed.

When that piston is at TDC do the lifters go down the same amount as the rest at TDC?

 

[Lou C]

Ayuh,.... Are you doing this with each cylinder turned to Tdc,..??

Yep you beat me to it, was thinking the same thing after I posted all that above....

 

[Lou C]

If you need it I can scan the procedure out of my OMC shop manual.

 

[Scott Danforth]

1995 should be non-adjustable valve train

 

[ste80]

Ayuh,.... Are you doing this with each cylinder turned to Tdc,..??

yes i did;
before to disassembling the lifter i was working in sequence 1-5 etc etc on tdc, but when i was putin 0 lash and 3/4 revolution i didn't have any torque at all, bolt was loose, i try olso with torque key set to lss than 10 nm but i was far away to that value , so i was thinking that if i have to use this method at least probabily i need some thread locker because like this i'm preatty sure that rocket bolt will loose after first switch on. i will try to post a video later

 

[ste80]

Cleaning the lifters I'll assume they were not marked so they didn't go back in same hole and same facing position?

All the rocker nuts should go down the same amount. The ones not fully seated need to find out why. Take the lifter back out and check to see if it goes all the way down when pushed.

When that piston is at TDC do the lifters go down the same amount as the rest at TDC?

tks;
lifter are markes, you can see the number in first picrture, then i put in the ultrasonic tank with mark on the top and in sequence so i could know where they goes. but anyway when i bought this motor it was already disassembled and lifter were in position, so i don't know ( i doubt) that old owner did this bfore disassembling so i'm not sure he put is same position. anyway, if my understunding is right the fact that they say to put in same position is the fact that they have oil inside so they are tighted for the same lobe of the cam, now that i remove all the oil, when pressure will go inside of the lifter they will be set on right position again ( in touch with lobes)


when you said: All the rocker nuts should go down the same amount; you meen 0 lash + 3/ or 27 nm? there is a big difference, because 0 lash + 3/4 turn, the push road is just little bit inside lifter) with 27 nm the bolt goes to the end of the tread and lifter is cloosed on stud. this what i fpund on manual 18






this is on pg 3a-22 of manual 18

 

[ste80]

Yep you beat me to it, was thinking the same thing after I posted all that above....

yes i do all cilinder in sequence 1-6-5-....

 

[ste80]

i try to upload a video. this is what's happen if i just go 0 lash and 3/4 of revolution. as you can see roket arm is still loose

i did also a check. i installed a dial gauge on top of push road and check the loading of the lifter ( now lifter is justcleaned so emty)
full gap 5 mm more or less
if i do 0 lash and 3/4 of turn, spring is loaded aprox 0,90 mm
if i go to 27 nm as per manual load is 2,35mm

on pag 3A-22 of manual 18 i find this

my is F356529.


mine is t05094lk, but on docs it shuld be lx

 

[Bondo]

i try to upload a video. this is what's happen if i just go 0 lash and 3/4 of revolution. as you can see roket arm is still loose

Ayuh,...... That cylinder doesn't appear to be at Tdc,......

 

[Scott Danforth]

with non-adjustable valve train on the 4.3, just snug up each of the rocker fulcrums to the stop location on the stud. then torque to 20 ft-lb (27 Nm)

you get a better torque reading if each cylinder is brought up to TDC on its own. however with non-adjustable, I just zip them on with the electric burp gun.

 

[Lou C]

Ahh you definitely have the adjustable valve train on that engine but are following the procedure for the non adjustable valve train or so it seems. Now why you have the adjustment valve train? Well the Romulus engine plant didn’t switch to net lash till 1995 you might have an early engine from that year from that assembly plant. In my pix above look for the engine serial #, see if it has a R preceding the number…

 

[Scott Danforth]

adjustable valve train is 3/4 turn from zero lash for each cylinder after each cylinder is brought to TDC (both valves closed)