ShaneBuss2

Hey guys I still have not got this thing running.

Engine is a Brand New 383 Stroker with Dart Iron Eagle 215cc heads, 580 lift solid roller cam, holley 800 double pumper.

I started the car after installing the engine and it would not idle, only run around 2500 rpms.. I think it's a timing issue.

Well i got to make sure I have the distributor right (not 1 tooth off), and i notice a bent pushrod on the #5 cylinder, i cant remember if it's intake or exhaust ... WTF?!?

I know none of the pushrods were bent before because i checked them. I also know all the valves were open and closed at SOME point because i turned the engine over and verified this beforehand.

I did not set the lash, as this was set by the engine builder.

I guess I need to measure the pushrods and order another one, I'm not sure what length I need.

Any ideas? HOw did i bend a pushrod when i verified all the valves were open at some point and closed at some point! The engine has only run a about 3 minutes total!

Aaron91RS

iTrader: (2)

Do we really need to post the next logical step.

Or should I mention an overlashed engine will barely start and my not even do that

jimmy_mac

you might want to figure out why that pushrod bent. If it is the only one then something freaky is going on with that particular valve. Something is causing extreme stress on that pushrod. You also might want to pull all of them and make sure no others are bent.

I assume since it is solid roller it was very easy for your builder to check valve to piston clearence and it was adequate. So if we assume the piston is not what is impeding the valves travel something else in the spring or rocker arm is causing it. Is the rocker arm slot long enough not to bind on the stud? Is the internal spring broke and binding in the external one? Check these things out before just replacing it and causing more damage. Good luck

ShaneBuss2

I inspected the spring as best i could without removing it. I did remove the rocker arm and it seemed fine.

I guessi will take the spring off and take a better look at it.

I might be missing something but if the valve is definitely closing at some point, is it even possible it's overlashed?

Thanks guys

jimmy_mac

being that this is a solid camshaft and lifters overlashing should not be a problem if a feeler gauge was used. I am pretty sure that is the way to set the lash. It has been about 10 years since I have messed with setting valve lash on a non hydraulic set up and it was a VW not a cheverolet but ye as long as you can fit the right size gauge between the rocker arm tip and the valve you should not be overlashed. Hydraulics are a little trickier due to bleed down in the lifters when the engine is not running.

Someone please correct me if I am wrong about that.

But anyway if you cant find anything apparent binding the springs or somehow impeading the valves motion have someone turn the engine over slowly while you check the clearence between the coils in the springs. If there is none then it is obvious you need taller ones. I can't remember what the actual tolerance is but it is probably on www.compcams.com in there tech articles.

I guess it could be possible you just got a faulty pushrod being that you had this professionally built but I would check for piece of mind anyway.

AlkyIROC

OK I may have missed any previous posts. Lets get some specs here first.

1. .580" lift. What cam grind is this?
2. What springs are being used? Were they set up to the specified install height? Are they capable of going to .580" lift with at least .060" between the coils?
3. What pistons are in the engine?
4. Has the block been decked?
5. What is the compressed height of the head gasket?
6. What rockers are being used and what ratio?
7. Have the heads been checked to allow the increased lift? The valve guides need to be machined down so that the bottom of the spring retainers don't hit the top of the guides. Do they use umbrella or positive lock seals?

There can be a number of reasons that a pushrod is bent. There's an interferance problem somewhere.

If someone else built the engine and all you did was install it and something went wrong, I'd give it back to the engine builder and tell them to fix it. Something wasn't checked properly.

F-BIRD'88

A bent pushrod means interference.

Do not *start this motor or crank the starter again* until this is solved.
If you have a solid lifter cam, you should learn how to properly adjust valve lash ***Yourself*** Its your motor.

You can assume the even thou your motor was "professionally Buildt" Some one F&*&^ed up.

Setting valve lash is easy. You'll need straight pushrods thou.
All you have to do is learn to correctly position the crank to ensure
the valve is fully closed and the lifter is on the back side of the cam lobe.
This is easy, listen up Remove all the spark plugs.
Rotate the motor by hand with the ignition off till the
intake valve of a cylinder just closes (on seat) now adjust that exhaust valve to lash spec with a feeler guage.
Continue rotateing the motor over by hand and when the exhaust valve just starts to open (first motion) adjust that cylinders intake valve.
Repeat for all the cylinders till you're done them all.

Now you need to verify that you have sufficient valve to piston clearance and retainer to guide clearance.

On #1 cylinder you are going to temorairly re set the valve lash
on both valves to 0 lash.
By using the same method to position the crank and valve train. except this time you'll spin the pushrod in your fingers till it just stops while adjusting the rocker nut. No feeler guage.
Now rotate the motor BY HAND over till you are at 20 deg BTC on the overlap stroke. Be sure your on the overlap stroke.
You'll know because the exhaust valve will be closing as you approch 20 BTC.
When you are at 20 BTC #1 overlap, tighten both the intake valve and the exhaust valve adusting nut 2 full turns and lock it down. Your valves on #1 cylinder will be both open .120" extra now
now rotate the motor over BY HAND past TDC to 20 DEG ATC.
Carefully. If you meet any solid resistance, Stop.....
stop at 20 deg ATC. If it passed this test you have enough .120"
valve to piston clearance.
Now slowly rotate the motor over again two full turns
By hand.
If you meet any solid resistance you have a problem that must be fixed. ( valve/ piston collision, rocker, guide to retainer, guide plates, offset lifters offset rocker, rocker stud, spring coil bind)
Am I missing anything?
Fix it.

If it rotates fine with only the resistance of the valve springs
You have at least .120" of valve to piston clearance and
at least that much clearance everywhere in the valve train.
Now loosen off those two valves and readjust then
as normally by the above method
remember intake closes ( on seat) adjust ex.
Ex opens (first motion) adjust intake valve.

Not too hard eh.
If all this checks out you should be able to restart your motor.
If you don't understand this stuff get some one who does
to help you. before you restart your motor.
After doing this I would do a compression test to see if you bent any valves.

If you get any solid resistance while doing this above test,
your engine builder needs to get in some other line of work.

ShaneBuss2

Here are the exact cam specs.. i was guessing from memory..


242 / 242 @ .050
.567 / .567
110°


I will try what you said... I'm pissed I have to do any of this though, that's why i bought a complete engine from oil pan to intake, and i shouldnt of had to even take the valve covers off!

The builder said to break the engine in, then re set lash.. I know how to set the lash, but he told me it was set when the engine was built. We'll see guys..

Thanks,
Shane

F-BIRD'88

Hopefully all that was wrong was one pushrod was not seated in the lifter when they set your valve lash.
Tat cam is not real big ans shouldn't cause any valve to piston clearance issues, but check it any ways. Only takes a few minutes.

jimmy_mac

Hmm, I don't know about a few minutes. He's gonna have to take the carb, distributor, intake, exhaust headers and any accessories bolted to the heads off. Unless there is another way of checking valve to pistion without removing the heads.

The more I think about it the more I think maybe you need to go talk to your engine builder. I personally like to do as much of my own work as possible, but since you didn't actually put it together you have no way of knowing if it was checked.

Jus bring that pushrod to him. I would think he would want to investigate himself.

F-BIRD'88

jimmy_mac:

If you'll carfully re read my post on checking valve train
interference, you'll find that it is done without dissassembleing
the motor at all other than the valve covers.
By over adjusting th valves by 2 full turns the valves are opened
an additional .120" therefore if you carefully rotate the motor over by hand and every thing clears, you have .120" clearance everywhere in the valvetrain and are good to go. No piston puddy, no dial indicators, soft springs or dississassembly nessessary.
I'know it was a long blurp but..... try it next time

ajm_shorty

yeah your lift is way too high

Ukraine Train

i had a similar problem. when i was installing the new timing set I aligned the crank gear dot to the wrong dot on the cam gear(there was an 'O' and an 'o' lol) so my cam timing was waaaay advanced and my intake valves ran into the pistons and bent my pushrods, one actually broke, but this is only one possibility. i would start by pulling a valve cover and look at your valve springs and see if any of them are binding and if you can, see if the retainers are hitting the vavle guides.

Marshall89ws6

yea make sure u check the springs..... my friend kev just went through 3 cams in 2 months b/c of crap springs on his new heads...... world products is actually reimbursing him for it.

a73camaro

Since you mentioned it was one of the inside cylinders (3,4,5,6) it is possible that the intake bolts are too long, push against the pushrod, and bend it.