Well, I've had enough of this 440 Mystery Motor

[moparedtn]

I see your point with a replacement engine. But unless if you are there every step of the build process, the chance of having a Monday or Friday motor could come back and suprise you, not that any of us want that to happen, but it could. Hate to see you go through this again for some other weird problem. If it was mine Id work with what i have and go from there. I like to figure out the "proverbial" puzzle per se.

Yessir, but in my case two other factors outweigh the curiosity factor:
time and money, both of which are in precious supply here.

 

[moparedtn]

Ed, at the risk of getting some hate mail my way .
here is my 2 cents.
If I recall the past posts you have a decent compression reading bottom end ? 135/140ish.
not top fuel readings for sure but useable.
Me, I was/am one of your 2 votes for replace but have one more idea. I may be wrong but I think your main goal was to just get the X up and running decent.
Why not just get a set of uncut/ recon stock heads , 452s , 906s , ect but stone stock, stock push rods, springs, rockers and shafts. The new cam/lifters was a question as to condition after this last round. so just use the regular old 440 mag grind that will work fine with the stock heads / valve train/ new cam bearings if needed. just put her back together like ma mopar did , take your 350/375 hp and motor off for the summer. a set of stock recon heads , cam kit & bearings, push rods and gaskets will be less cost than the replacement engine and you know it will all work fine together as long as the pistons are under the deck a bit.

Yep, cylinders all were within 5psi or so around 130.
If not for the fact the previous set of heads (that now sit on my shelf) also had issues (remember the bent pushrod and such?) , I'd tend to agree with you.
Those were with the stock rockers/shafts, pushrods, etc.
If I were to go fetch yet another set of heads + replace cam bearings (pulling out engine to do so, right?) + replace cam, pushrods & lifters again - well heck, might as well just get one rebuilt at that point. Same difference.

 

[Garys1969RR]

First thing to do, Ed, is use the scientific method. Step 1) Identify the problem. I know you have been trying to do this, but throwing parts at it in hopes that will fix it gets expensive, time consuming, and laborious. And most of those things, we do not have alot of. HAHA. Heck, I'm tempted to get on a plane and fly down there and fix it for you! Really! Or at least give it the good ole college try! How far are you from the nearest major airport?

 

[BeatersRus]

Yessir, but in my case two other factors outweigh the curiosity factor:
time and money, both of which are in precious supply here.

seems like another option would be to snag a 383 from one of these members and drive on that while you piece together a better 440?
i see a lot of guys take out perfectly good 383`s...
its a weekend job to swap.

 

[miller]

Yessir, but in my case two other factors outweigh the curiosity factor:
time and money, both of which are in precious supply here.

Believe me...fully understand. And can understand how frustrating a motor can get, when things don't fall into place.

But, you might as well understand, even another set of heads might not be a fix. Not unless you know where the block's deck height is. Anybody know a way to measure deck height, with just the heads off? I don't. Heck, for all I know, the thing is bone stock. Though, from the bolt hole line-up, says no.
You said stock parts off the valve train, when you changed cam?

If stock head gasket thickness is known, just a little checking might tell. Earlier gaskets are .020...don't know for sure on your 'later' motor, but could be. Getting that down, and finding why the bolt holes don't line up, could be simple, maybe even a simple fix.
Something is there. What? And making sure of the tappet thing.

Just trying to look this thing clear. Take it slow, best of luck.

 

[moparedtn]

First thing to do, Ed, is use the scientific method. Step 1) Identify the problem. I know you have been trying to do this, but throwing parts at it in hopes that will fix it gets expensive, time consuming, and laborious. And most of those things, we do not have alot of. HAHA. Heck, I'm tempted to get on a plane and fly down there and fix it for you! Really! Or at least give it the good ole college try! How far are you from the nearest major airport?

About an hour.
I do appreciate the thought.

 

[moparedtn]

seems like another option would be to snag a 383 from one of these members and drive on that while you piece together a better 440?
i see a lot of guys take out perfectly good 383`s...
its a weekend job to swap.

Yeah but no.
Doing this once. I'll be darned lucky if I get to do that much.

 

[moparedtn]

Believe me...fully understand. And can understand how frustrating a motor can get, when things don't fall into place.

But, you might as well understand, even another set of heads might not be a fix. Not unless you know where the block's deck height is. Anybody know a way to measure deck height, with just the heads off? I don't. Heck, for all I know, the thing is bone stock. Though, from the bolt hole line-up, says no.
You said stock parts off the valve train, when you changed cam?

If stock head gasket thickness is known, just a little checking might tell. Earlier gaskets are .020...don't know for sure on your 'later' motor, but could be. Getting that down, and finding why the bolt holes don't line up, could be simple, maybe even a simple fix.
Something is there. What? And making sure of the tappet thing.

Just trying to look this thing clear. Take it slow, best of luck.

One thing I'm not entertaining is just another head swap.
I have no reason to doubt that these are "bad". Machined for sure, but not bad.

Yes, these are the stock rockers and shafts that I spent some time cleaning spotless. No reason to doubt them, either, unless one or some are slightly bent.
I saw nothing wrong, but that doesn't mean anything.

One thing I don't have the luxury of is taking it slow.
That part is beyond my control at this point. I'll be lucky if I get the time to get this done, honestly.

The pushrod checker arrived today. I'll try it out tomorrow and see if I can figure out anything.
Thanks, y'all.

 

[miller]

One thing I'm not entertaining is just another head swap.
I have no reason to doubt that these are "bad". Machined for sure, but not bad.

Understand. Heads not particularly bad...but, thinking about how you have said the motor acts...one last thing comes to mind. Sticking valves, for whatever reason...something you sure can't 'see'.

 

[mopar 3 B]

The pushrod checker should shed more light on things and what is going on. I still do not think the valves are closing completely when the engine is hot and it takes compression to make it run right.

 

[moparedtn]

How much additional should I be using to compensate for the desired lifter pre-load?

 

[miller]

You need to know two things first.

On those 906 heads, were the valves, valve springs already mounted up? The two things you need to know...either way...if the valves are seating good, all the way, and will hold pressure. Next, valve to guide clearance. Exhaust valves need slightly more clearance, since they take direct heat, the flame front. At the very least, using a prybar, or whatever, move each valve through the guides, to see if they will open, and close by
the spring pressure.
If so, the tappets also need to travel freely when compressed, up and down.
Then, your ready to look at push rod pre-load. .020 to .040 usual, or even more, depending on who you talk to. It's measured, from the bottom of the 'cup' retaining clip, to the top surface of the cup.

 

[mopar 3 B]

I would start checking push rod lenght on the cylinder that the plugs look good on first and the fouled ones last. Record the difference in preload and split the difference to obtain the push rod length.

 

[moparedtn]

You need to know two things first.

On those 906 heads, were the valves, valve springs already mounted up? The two things you need to know...either way...if the valves are seating good, all the way, and will hold pressure. Next, valve to guide clearance. Exhaust valves need slightly more clearance, since they take direct heat, the flame front. At the very least, using a prybar, or whatever, move each valve through the guides, to see if they will open, and close by
the spring pressure.
If so, the tappets also need to travel freely when compressed, up and down.
Then, your ready to look at push rod pre-load. .020 to .040 usual, or even more, depending on who you talk to. It's measured, from the bottom of the 'cup' retaining clip, to the top surface of the cup.

When I say they were "fresh from the machine shop", that's exactly what they were - shipped to me from a friend in Indiana direct from a machine shop.
My friend has built engines for decades and the machine shop is his personal favorite, so it comes recommended to say the least.
Bad valves were replaced along with guides and seals and it shows.
They were also decked flat, with a very sharp edge to the mating surfaces.
Beyond that, I've no clue.

I suppose I can pry on rockers to see the valves actually move?
I also need to remember to do a rudimentary "thickness" measurement like was shown in an earlier post.

 

[moparedtn]

I would start checking push rod lenght on the cylinder that the plugs look good on first and the fouled ones last. Record the difference in preload and split the difference to obtain the push rod length.

I'll probably bring timing mark around to TDC and check #1 first, sort of in the old valve adjustment order. Go from there and check a bunch of them.

 

[Garys1969RR]

When it starts missing, pull the plug wires one at a time to see which one is not firing, proceed from there. Maybe check compression on that cylinder ? Have to narrow this down to the bad cyl. Or cylinders.

 

[miller]

When I say they were "fresh from the machine shop", that's exactly what they were - shipped to me from a friend in Indiana direct from a machine shop.

Then, I'd say probably no problems there, including sticking valves.

I know on these things, anything can make 'em not act right, so, at times gotta climb out of the box, and find out why. There's 'something' making the probs, okay?

Another thought, (damn, will he go away! Ha!) is what happened on my last build, 20 years ago. Set it all up, fired off, and ran like a total piece of crap! Beat my brains out, trying to figure out why, checking and re-checking.
Wound up a bad set of 'new' spark plugs, 5 out of 8 had cracks, wouldn't fire right. But, of course, never dreamed it could be.
After the thing actually ran, would get to crap, after getting miles, and many plug changes. Wound up, crummy plug wires! So, you get the idea.

 

[dvw]

I've had "fresh" heads from a big name race builder. One set stuck a valve from a tight guide on the dyno, they never noticed. Another set had guide clearance as loose as .018" (that's right 18 thousandths). This was years ago, never used them again. You can't tell guide clearance with out removing the springs. Tappets will not compress if they have been run and are in good working order unless pressure is held on them a long time. Otherwise they would be bleed down when the valve was open in the motor.
Doug

 

[miller]

I've had "fresh" heads from a big name race builder.

Never had that problem...always do my own.
But, understand not everyone has that option.

 

[BeatersRus]

Yep, cylinders all were within 5psi or so around 130.
If not for the fact the previous set of heads (that now sit on my shelf) also had issues (remember the bent pushrod and such?) , I'd tend to agree with you.
Those were with the stock rockers/shafts, pushrods, etc.
If I were to go fetch yet another set of heads + replace cam bearings (pulling out engine to do so, right?) + replace cam, pushrods & lifters again - well heck, might as well just get one rebuilt at that point. Same difference.

just a thought,and yes its random but
have you checked the lifter valley webbing in the block for cracks?
its rare but ive seen them fail.