All Small Six Swapped my head, engine won't start...

[arc_johniv]

Over this past weekend I was driving my '63 Falcon around when I noticed the temperature rising at an alarming rate. I overheated the engine twice just trying to get home (hit about 250°). Got home, pulled the heads and sure enough... Valves were ghost white.

Rather than doing a valve job on that head. I decided to repurpose the head off my '66 bronco (since the engines are the same 170 and the bronco's getting swapped). Seemed to be a pretty simple bolt on swap with some slight accelerator reworking, but other wise went on fine. Go to fire it up, and the engine sound very slow when cranking. Checked the battery and solenoid, but they seemed right.

I keep trying but the engine won't start. I've got air, fuel, and spark; so my only other thought was compression.

Hooked up a compression guage, and to my suppressed I had 0 pounds on every cylinder! I checked the gauge on another project to make sure it wasn't the guage, and the guage was fine.

The valves and springs are off the bronco, but all the other timing parts are the originals from the falcon. Are the springs heavier from the factory? I took the valve cover off and cranked it so I know they all move and all the valves open...

Planning on pulling the engine and doing an autopsy this weekend unless y'all can think of a simple reason.

Any ideas? Rings got to hot and shattered? Different head design for a later year?

Thanks

 

[pmuller9]

It sounds like the valve are not closing on the valve seat.

Did you use the rocker arm assembly and pushrods from the 1963 head?
Do you have rocker arm to valve stem clearance?

 

[arc_johniv]

It sounds like the valve are not closing on the valve seat.
Do you have tappet clearance?

Refresh me real quick. Is tappet clearance between the rockers and the springs, or between the rockers and the pushrods? Or something completely different?

 

[pmuller9]

Refresh me real quick. Is tappet clearance between the rockers and the springs, or between the rockers and the pushrods? Or something completely different?

It is between the rocker arm tip and the top of the valve stem.
The clearance should be .018"

 

[arc_johniv]

It sounds like the valve are not closing on the valve seat.

Did you use the rocker arm assembly and pushrods from the 1963 head?
Do you have rocker arm to valve stem clearance?

Not sure if they have clearance... I'll check it when I get home. If it's too tight, do I adjust the rocker arms individually or loosen the rocker shaft a bit?

 

[pmuller9]

Did you use the adjustable rocker arm assembly and pushrods from the 1963 head?

 

[arc_johniv]

Did you use the adjustable rocker arm assembly and pushrods from the 1963 head?

Yes, everything except the valves and springs

 

[pmuller9]

Not sure if they have clearance... I'll check it when I get home. If it's too tight, do I adjust the rocker arms individually or loosen the rocker shaft a bit?

You adjust each rocker arm individually.

 

[arc_johniv]

That's it! I went in with a feeler gauge and the socket and found out that every single rocker was way too tight. Loosen them up a bit to 0.018, and now it fires right up! One or two of them seem a little loose, but that's way better than it was earlier. Thank you so much!

 

[bubba22349]

If its an original 1963 or newer engine than it should have the hydraulic lifters in it (that was the First Year for hydraulic lifters in most of the Falcon cars). You will probably have to go through and adjust all them correctly to zero hash and than a full turn tighter. Did you find out what caused the engine to overheat? Good luck