cudak888: 1972 Q-code - cam failure pictures

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Hack mechanics use multiple gaskets and spacers to help isolate the carburetor from manifold heat. Cooler carbs mean cooler fuel, less opportunity for heat related issues. I guess that makes me a "hack" mechanic!! :D
That's what they make spacers for ;)

-Kurt

 
Dumb question: are you sure that the pushrod pretzels were due to your attempts to fire the motor?

Could it be they are the reason it was partially disassembled when you bought it?

BTW: neat find!

 
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Most likely misses timing chain jumped mister timing gears, kinda explains the distributor being off. Bent valves usually accompany the twisted pushrods. I would look at everything twice.
Timing chain appears to be new - it's not a stock unit. My bet is that it was put on the wrong key slot. We'll see.

-Kurt


Some other info: It has double springs on the heads. Can't see the timing marks yet, and I'm not dressed to tear into it now.

That said, I've got an engine stand, but no engine hoist - yet. That shall change, as I don't trust ANYTHING about Jethro the Rebuilder's motor at this point. I'm going to do a few things while it is still in the car, but if it doesn't pass a leak-down test, this engine is coming OUT. No telling what rings they put in it either.

-Kurt
I have a set of pushrods and probably a set of rocker arms you can have for free.

im 20 minutes south of you.

Timing didn't do that for sure, valve may have been stuck or rocker arm broke, or valve hit piston.

Let me know if I can help.

3xx-726-324six

Jorge

 
Dumb question: are you sure that the pushrod pretzels were due to your attempts to fire the motor?

Could it be they are the reason it was partially disassembled when you bought it?
Good point. No idea, really, though the owner claims to have run the engine previously.

The valves bind when trying to turn the engine over by hand, so the timing has jumped in one form or another.

Kurt I have a Holley 750 DP rebuilt if your interested

I have some room on the price

http://www.7173mustangs.com/thread-holley-750-double-pumper
Won't need a new carb for a while, Q. Something tells me that I'll be spending that much in gaskets :p

I have a set of pushrods and probably a set of rocker arms you can have for free.

im 20 minutes south of you.

Timing didn't do that for sure, valve may have been stuck or rocker arm broke, or valve hit piston.

Let me know if I can help.

3xx-726-324six

Jorge
I'll take you up on that. Will call tomorrow.

Rocker arms are fine. Valves hit the pistons, and they still are if you try to turn it over.

-Kurt

 
Rocker arms are fine. Valves hit the pistons, and they still are if you try to turn it over.

-Kurt
The pushrods are to long for the installed cam..head setup..the valve heights could be wrong..You need to start from square 1..I would pull the heads measure them to see if they have been shaved..see whats going on..It is obvious that a stock pushrod length isn't going to work..The yokel that built worked on the motor probably installed the cam with the stock length pushrods..common mistake..You can't just throw a higher lift cam in with out verifying the correct installed valve heights & the correct length pushrods so the valves don't hit the pistons

 
The pushrods are to long for the installed cam..
Going to pull one that isn't bent and measure it. Should be stock pushrods though; cam is a Comp 268H, P/N 32-221-3. Comp Cams specs 8.412" rods for it - stock length.

-Kurt


Rods are just shy of 214mm; my guess by squinting between the lines is around 213.6mm or 213.7mm - which is 8.409" through 8.413".

Close enough to 8.412" in my book. Sure isn't the slightly smaller 8.400" size.

-Kurt

 
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The pushrods are to long for the installed cam..
Going to pull one that isn't bent and measure it. Should be stock pushrods though; cam is a Comp 268H, P/N 32-221-3. Comp Cams specs 8.412" rods for it - stock length.

-Kurt


Rods are just shy of 214mm; my guess by squinting between the lines is around 213.6mm or 213.7mm - which is 8.409" through 8.413".

Close enough to 8.412" in my book. Sure isn't the slightly smaller 8.400" size.

-Kurt
Right.. but if the heads or block were milled...Or new valves installed..valve seats..etc.That changes everything..Not to mention if pistons were done..Ya just don't know with out pulling a head to see..Lots of variables that can change the length required..Who even knows if thats the cam thats in there with out profiling it ..Not only that you need to see if you got lucky & only bent a pushrod..There may be a cracked damaged piston under there too..Just trying to save you some grief..It's only a few more bolts to pull the head..

 
Timing marks lined up.

Tried pulling the lifters, and found a couple that are mushroomed/burred. This was the worst one that I could pull:

8xivcl.jpg


One or two of the other lifters won't come out by hand. More burring. Going to pull them from the bottom to prevent damage to the lifter bores.

Anyone want to bet that these yokels didn't bother to break in the cam, thereby burring the lifters - causing them to bind in their bores when fully extended - with the end result being Don's off-color Mother Goose story about Mr. Piston Stud, Ms. Valve, and Limpy the Pushrod?

Looks as if it's my opportunity to return the thing to a stock cam...provided anything has survived; preferably the lifter bores.

Right.. but if the heads or block were milled...Or new valves installed..valve seats..etc.That changes everything..Not to mention if pistons were done..Ya just don't know with out pulling a head to see..Lots of variables that can change the length required..Who even knows if thats the cam thats in there with out profiling it ..Not only that you need to see if you got lucky & only bent a pushrod..There may be a cracked damaged piston under there too..Just trying to save you some grief..It's only a few more bolts to pull the head..
Agreed. I'm this far already.

Just the same, I'm going to do a leak down test beforehand, just so I have some data on each valve and the rings.

-Kurt

 
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Nice..Man every corner you turn you keep finding more & more..I'm thinking these guys attempted a cam swap top end rebuild that didn't have the results as expected rofl...A easy way to get the lifters out from the bottom is to get a piece of pvc pipe the diameter of the cam..cut a rectangular hole in a section..get a telescoping magnet..Insert the pipe..into the cam journals..rotate to line up the rectangular hole with the lifter bore..insert magnet..push lifter into the hole in pipe where magnet is waiting..pull out..A great stock cam is the 72 Q code cam I have the part number grind..available from rock auto..


Kurt,

Btw..I have most of a gasket set here left over from the motor I just built..

You can have if you want just pay the shipping

IMG_0251.JPG

 
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Nice..Man every corner you turn you keep finding more & more..I'm thinking these guys attempted a cam swap top end rebuild that didn't have the results as expected rofl...A easy way to get the lifters out from the bottom is to get a piece of pvc pipe the diameter of the cam..cut a rectangular hole in a section..get a telescoping magnet..Insert the pipe..into the cam journals..rotate to line up the rectangular hole with the lifter bore..insert magnet..push lifter into the hole in pipe where magnet is waiting..pull out..A great stock cam is the 72 Q code cam I have the part number grind..available from rock auto..
As I said, welcome to Hack the Hick and Jethro Bodine Engine Rebuilds, Inkorporated. I should have figured they screwed up everything inside when I kept finding everything done wrong outside.

Incidentally, are 351W and 351C lifters the same overall length? Part searches seem to indicate they are one and the same. About the only thing that appears to have been put in right is the timing chain, which - thankfully - appears to be intact with less than 1/4" deflection.

I assume the PVC trick is done with the lifters retained upwards from the top, correct?

EDIT: Yep, I'll take you up on the gaskets! Will PM.

-Kurt

 
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result being Don's off-color Mother Goose story about Mr. Piston Stud, Ms. Valve, and Limpy the Pushrod?

You considered that joke "off-color"

 
I'll off the color of this thread. That thing's f*&^%$ up. Plan on pulling it and completely going though it.
NOW that's colorful , reminds me of forum days gone by :p

 
Well, I hate to disappoint you fellows, but I pulled the passenger's side head today (pictures tomorrow; too dark by the time I finished - had to pull it out with the header and half of the rotted exhaust due to stuck bolts), and cylinders #2 and #3 - which had notably bent pushrods - don't have marks. Cylinder #4 is fine too.

Cylinder #1 has three small nicks - but in the center of the piston. The carbon deposits in that cylinder are a bit oily. Head gasket leak?

Valves don't show any nicks at all - but the intake ports are clearly marked "FORD." Ugh. Stock two-piecers. More stuff to spend on...

-Kurt

 
So I guess I need to understand how a backfire creates that kind of damage on 2 different cylinders.
Born lucky, I guess - but I doubt it was the backfire.

Perhaps the original Ford valves are sticking in their stems from when the P/O replaced the springs? Binding valve guides when hot (or just binding, period)?

I might remove one of the springs on the troublesome valve just to see how it feels by hand. There's a shop in Hialeah that I trust for cylinder head work - Dad used them countless times for diesel cylinder heads, always top-notch - I might have them do a more thorough inspection.

-Kurt

 
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