Hi,I am replacing the head gasket on my 1966 ford Mustang engine and have been told that the hydraulic lifters show some wear and have been told to replace them. I have read that replacing the hydraulic lifters may cause more damage due to the other parts may be worn and have also been told that replacing them may also improve the performance of the engine. Also I have none adjustable rocker arms and here is another question in reference to rocker arms, reinstalling the rocker arms. Since these are nonadjustable all I do is install them a torque them to specification, correct? Is it correct that if your engine has Hydraulic lifters then your engine has nonadjustable rocker arms? And if you wish to install adjustable rocker arms the cam has to changed?Any help appreciatedThanks againRaul
lifters are NOT flat on the end.. they are slightly convex..(== the cam lobes are ground at a slight taper... so the lifter rotates and only touches one small place slightly off center like this...cam lobe\(== lifter see the angled lobe facing verses the convex lifter end..this is sideways.. as its the only way i could type it out.. if you swap lifters... on a used cam.. or change their position.. you will RUN INTO a flat cam soon... as the lifters are broken in to the face ... move them. or install new ones... you take a serious chance of wiping the lobe off the cam... you might want to stick a screw driver or figure out some kind of device to sit down on the lifter with the head off... use a remote starter button to crank the engine over a few turns with your hand on it.. . check each lifters LIFT .. with a few turns of the crank.. if you get one that does not seem to move as much as the others... perhaps its time to swap the cam also.. sorry... this should only take about 10 minutes.. please unplug the wire off the I terminal on the starter solenoid so you don't power up the ignition system where you can get shocked.. you can if you are really worried about the lifters... attempt to get them out with a lifter pulling tool... yep.. they make them... ONE BY ONE>. or drill a block of wood with 12 holes.. 1" or 24MM something the lifters can fit in.. a second block with matching holes and a pair of screws... so you can remove the lifters... place them in order... screw the upper block on to prevent idle hands from inspecting and reordering the lifters... sorry.. i had somebody do that to me... warning. lifters in a block for a long time.. may have a mushroom over the end.. that will tear up the lifter bore if you attempt to remove them... i almost always use strong carb cleaner spray as i work the lifters up and down.. farther and farther never leaving them stuck upward... this spray works the varnish off the sides and allows you to easily remove them.. you can on a clean white work towel .. take the lifters out of your holder and work on them ONE by ONE.. the internals are select fit and MUST NOT BE INTERCHANGED... or you will have issues...cleaning with either brake cleaner or carb spray cleaner... you will want to NOT leave finger prints and use some very thin motor oil to coat them for reassembly.. like 0W-20 weight. do not fill them. this is just a coating.. i leave them dry when i do them but i make sure that my hands are totally clean and dry for reassembly.. so i don't leave fingerprints on the internal piston..lifter preload... on NON adjustable valve train.. is usually accomplished by installed height of the valve stems by measuring before disassembly... and comparing known specs..on assembly... with empty lifters or after applying pressure over several minutes to each to bleed them down... you measure the clearance at the rocker arm tip.... i don't recall the clearance for the straight six motors with the lifter bottomed out.. probably 0.095 to 0.150" at between the top of the valve stem and the tip of the rocker arm.. again holding the lifter bottomed out with a lever on the rocker arm.. i have a picture somewhere..some parts brands carry pushrods in stock lengths... and a few carry them in stock but also -.060" and +.060 lengths ... i usually get these from a US company called elgin engine parts.. melling does not make them for all applications...you can tell i have been thru this a few times...
Hi, been really busy with work.Thanks for the help. I have had the head resurfaced and have not done more than thatagain work.Again thanks for the help!Raul
RaulhIf I were you I would pull the cam out and examine it really close.The lifters will wear, and the cam will wear as the mileage goes up.You didn't say how many miles you have on your engine, but it doesn'ttake much to have a cam wear the lobes. If the engine was low on oil and the load lifters and camshafts have almost instantly wear happens.If your not familiar with it. Have a mechanic look at it.Bob