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Pushrod length problem with pics

It sounds like it, they were also referencing someone's 2.5L so maybe they were mixing my motor with their other experience. I didn't get to see it with the valve cover off at the shop. I will call them tomorrow to see when I can pick it up. I don't know if I want to trailer it or not. I drove it there but that doesn't mean anything.
 
Here is a quick method to check preload. The text is from Crane Cams:
Fast and Easy Way to Check Hydraulic Lifter Preload when using Non-Adjustable Rocker Arms

With the cam, hydraulic lifters and pushrods in place, install your rocker arm assembly. Use the prescribed method in your repair manual and torque down all the valve train bolts in the proper sequence. Pick a cylinder that you are going to check. Hand rotate the engine in its normal direction of rotation until both valves are closed. You are on the compression cycle for that cylinder. (At this position the valve springs are at their least amount of tension making the job a little easier to do.)

Wait a few minutes, allowing the lifters to bleed down. Now, lay a rigid straightedge across the cylinder head, supporting it on the surface of the head where the valve cover gasket would go. Using a metal scribe and the straightedge, carefully scribe a line on both pushrods. Now carefully remove the torque from all valve train bolts, removing any pressure from the pushrods. Wait a few minutes for the pushrod seat in the hydraulic lifter to move back to the neutral position. Carefully scribe a new line on both pushrods.

Measure the distance between the two scribe marks, it represents the amount of lifter preload. If the lines are .020" to .060" apart you have proper lifter preload. If the lines are the same or less than .020" apart you have no, or insufficient, preload. If the lines are further apart than .060", you have excessive lifter preload.
Click to expand...

I would also roll the push rods on a sheet of glass to ensure they are straight.

Check the rocker at its pivot point for binding with the rocker body and pivot. Depending on the cam it could bind there.

Check that the valve springs aren't binding at full lift as well as the retainer to valve seal.
 
Well I got the truck back from the shop, the guy said the rockers were all over the place again. I guess I'm going to park it until I can pull the motor again to tear it down to find the noise and have the head looked at to get the proper size pushrods installed. Not looking forward to that again!!
 
No clue, if I have some other type of noise other than the obvious rocker/pushrod issue I should tear it down to investigate. Who knows what cam is in it. It's got a little lope at low idle but that's all I know. I am kicking myself for not getting this squared away before I put it in the truck. I guess I was pushing myself to get it done. Who knows maybe I will not like the parts in the motor and upgrade when it's torn down. I am on the fence on ordering the crane cams pushrod length checker. I can get one problem fixed but if the cam is worn or the valves or anything else it would just be money down the drain since I would buy the pushrods and straighten all the rocker bridges again. I wish I had more knowlege on this front.
 
Do you have a dial indicator and magnetic base? If not, get one.

I don't think the incorrect pushrod length can cause the rockers to do what you say they are doing. I think something is binding.
 
Ok,

So I am going to pull the engine back out and take it to a machine shop to have them tear the engine down to determine the cause of the noise. I wanted them to spec out everything to see what's exactly in it, CR, bore, etc.

So if "you" were to have this done what would you do? I don't know if I want to throw a different cam in it or upgrade the rockers to rollers. I don't know if any other upgrades will/could help. I want to see the C/R to make sure what gas to put in it.

I want it driveable without any adjustments other than normal maintenance. Suggestions welcome.
 
You have members here suggesting something in the valve train binding well without a doubt , and I believe its happening at maximum cam lift , We do have a variety of unknowns here , Being a stroker motor , thats just referring to the crankshaft throw in comparison to the factory crankshaft , due to change of crank throw (length of stroke) there is a good chance the block was decked , 10/20 ??? who knows from what I have read here , apparently the head has had valve guide work , once that was done , valve seat faces would be dressed and valves matched to the seats ,,,, Its unknown how deep the valves were seated into the head and the resulting valve stem height ..... Now lets compound this all by cutting the head to assure a flat surface for the head gasket on both the engine deck as well as the cyl head surface , who knows what was removed 10 / 15 / 20 ....... so we have an unknown valve stem height on the rocker side of the head , a block thats possibly been decked , a head thats possibly been surfaced . resulting in a cyl head sitting an unknown distance closer to the camshaft . 40 thou , 50 tho, who knows ... your rock ers operate at a ratio of 1 to 5 lift as an average , they could be 1to6 or 1to6.5 this is the multiplier after the cam has pushed the pushrod up against the rocker , resulting in the increase of motion on the valve side of the rocker ....... I believe your cams lift with the combination rocker ratio (unknown) is causing the valve to run out of travel in the head , on the valve side of the rocker arm , Thus bending the rocker bridge , you can pay the shop to measure it all , or cheat the system and try a variety of shorter pushrods on one cyl intake and exhaust for fit --- until you are not bending the rocker bridge --- and then reduce the pushrod length by a bit more so as to not have bending happening while high rpm float is going on ....... its the long and short side of a triangle you are working on .
 
I dont know how much you want to do yourself , or leave to the machine shop , you need the deck height from the crankshaft and to know how the head is set up .... just an after thought that might save you some $ .... Its a cheap jury rig work around from race car days ... remove the cyl head , just for an increase in measurements/dimensions , add an additional old head gasket to the one on the motor (total 2) , real good tighten down of the head bolts (60%of spec) to give yourself a decent clamp , I would not think they need to be torqued all the way to spec due to the fact they have already been crushed from the initial assembly , remove the coil wire and spark plugs ,,,, get the motor turning with or thru the starter , if its a manual trans .... Even better , make sure you have Oil in the motor and have a friend's vehicle , drag you down the street ....remove valve cover .. check your Rocker bridges for bending ... depending on manufacturer , the added head gasket will be "close not exact' to what may have been removed during block deck and cyl head surfacing , it will not compensate for valve depth when seating into the head , Possibly it will also be close to how much too long your existing pushrods are. now its not going to be a race motor like this , but could give you a bit of correction to the valve train geometry.
 
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really want to get barnyard ... after above and you have shorter pushrods in , get #1 cyl to TDC , so cam is on baselobe , while increasing and decreasing clamp of bridge rocker bolt use a feeler gauge on the valve side of the rocker till you have no clearance , loose rockers are top end power curve , overly tight rockers will affect bottom end of motor power (in thousandths) . crazy adjust patch procedure ... shim rocker bridge by a known thickness till you have about 1/2 turn of bridge bolt for zero clearance between rocker arm and valve stem , Like would be done with a hydraulic lifter adjustment on a running motor , to remove or zero lash the rocker . this will give you tension on the pushrod and get the lifter core off of the retaining spring . You are going to need change the push rod lengths , how you go about finding the correct length .... well its time and or money .
 
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If you are doing a cam base lobe / TDC clearance set up and measuring travel of the rocker in comparison to valve travel by tightening and loosening the rocker bridge bolt , with all the spark plugs out , do #1 cyl , but have the other 5 cyl pushrods all removed , for ease of engine rotation , giving you a better feel for what you are working on removing any tension or possible bind from the other valve train assembly. " """ Do Not By Any Means , Spin the Motor With The "Starter""" , without the pushrods In , You Can pop a Lifter Out of Its Bore . This is all by hand/wrench .
 
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What are the details of the engine? Valve springs, cam shaft, decked, etc? What is your preload set at now?

Something is binding, which you should be able to find yourself. Here is a list of where to check:
-Spring binding at max lift
-spring retainer binding on valve seal/valve guide
-rockers running off of valve tip at max lift (doubtful)
-Retainers hitting rockers (again, doubtful)
-Rockers binding on trunions, easily missed, if need to check with soldering wire
-Rockers/springs binding on valve cover, look for marks on valve cover.
-Push rods binding on head.
 
^^^^

I have no idea what is "IN" the engine, all I know is what year the crank is and head and block. I saw that the windage tray has two washers on it for clearance that's pretty much it. No idea how the block was prepared, cam or other parts. I am going to have the shop tear down the engine to give me measurements on that stuff. The only thing I was wondering is what performance parts I should put back in it after it is pulled apart.

The main concern is the noise it makes when running. I most likely should get new rockers and pushrods and/or lifters if they have been abused. Just looking for advise on if anyone has run roller rockers and if they are a good option for me over the stamped ones. Thanks for all the options for doing it myself, to be honest I just don't know enough to do it myself to feel confident it will last.
 
gradon said:
You should buy Comp Cams' 7704-1 pushrod length checker and see what length pushrods you need. Variables that change with the stroker/engine work are shaved head, decked block, cams with larger/smaller base circles, and rockers. I would not run it from the way your pics look. 96 head/block stock deck height is 9.450-9.456" and pushrod lengths are 9.640-9.660". I ended up using 9.602" pushrods for my 4.6l.
Click to expand...

That is what I ended up using too on my Stroker (4.6)...Plus I use Joe Gibbs HR4 10w30 oil.Bosch distance plus filter.

http://www.drivenracingoil.com/dro/hr-4-synthetic-10w-30.html
But I pay $7 a quart
 
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