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4V head Disassembly
#1
Hey,

I got the 4V heads off the Cleveland. They are 73 heads on a 72 block. Looks like 2.04 valves. Haven't measured them yet but I think 73 heads have 2V valving. Not sure what I should do. I am replacing the rockers due to wear. It had a valve job 10K ago before I owned the car. The springs look good. Lots of carbon on the valves. I'm thinking of taking everything apart and inspect / clean. I ran the car two years ago after it sat for 6 years unregistered. I only ran it for the summer and then started tearing it down. A couple of questions.

If I replace the rockers do I have to replace the rods too? They look fine but not sure. I am going to put the springs back in the same locations along with the rods if I reuse them. I will replace the head bolts as suggested.

If I strip everything off whats the best way to clean up the heads getting ready to paint?. I bought some Gunk degreaser. Any problem washing these heads down with degreaser? Pressure washer or not?

My buddy want me to get a triple valve job on the heads but I think it's too much for me to handle $ at this point.

Also if the valves look good how should I clean them. Any reason I should replace if they look good. I think the answer is go with stainless but not sure.

Thanks for the help!

Chasing Rust
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#2
I'd plan on replacing them with new 1 piece, 1 groove valves anyway. One of the main failure modes of the Cleveland is dropping a valve from the multi groove keepers letting go, or the head popping off the original valves.

1973 Mach 1 Q code 351 4V, 9A paint, standard interior, 3.50 rear, C6 trans.
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#3
Pictures of the heads, top and bottom would help.

How much is a valve job these days?

I think everyone's idea of a valve job is different. Didn't they replace the springs and valves at that time?

How do you know you don't already have a "3 angle" valve job:

[Image: 3anglevalvejobtj3.jpg]

Not even I recommend keeping 2 pieces valves. Confirm you have a one piece valve and then you can use a drill and a brass wire brush on the valves to remove the carbon.

Wash the heads with whatever you like. I don't see pressure washer as a necessity. Just make sure to oil them down after(Most use WD-40, I use Kano KROIL).

I don't know how to test a pushrod. But if it had 50k plus miles on it, I would replace it...but remember this pushrod fact-- size does matter...down to .010 even.

[Image: 11jmcuc.png]
351C Bold Manners, Brash Attitude
Favorite Teams: Michigan Wolverines and Whoever Is Playing Ohio State.

When I drive past a herd of cows, the cows MOO at me
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#4
If I understand correctly the stock valves were two sections welded together? Is there a way to test the springs?

Chasing Rust
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#5
Darren 72;105672 Wrote:If I understand correctly the stock valves were two sections welded together? Is there a way to test the springs?

That's correct. I would never put heads back together with the stock, two-piece valves. There are gruesome stories with gory pics on this site that clearly depict what can happen with stock two-piece valves.

If you Google it, you can find some info, I've never tested the springs myself.

Doc

[Image: 6y14ea.jpg]

Project started 8-7-10
Completed: All new suspension, rebuilt 351C H Code bored .030 over with mild cam and intake, new 3.50 TracLok, custom exhaust system
Current "mini-project": interior upgrade Undecided
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#6
Most valves are a 2 piece design where the head and stem are friction welded together. Most of the failures of stock valves are not the result of the weld breaking, it is a result of the valve keepers not holding the multi groove valve stems. When the keepers let go the valve drops and makes quite a mess. I would not hesitate to run a good set of 2 piece valves with single groove stems and keepers. True 1 piece valves are very expensive due to the amount of material cut away in production.

My 2 cents worth.

Jeff T.

Low buck, touring style, '73 Convertible "rolling restoration", 351c, 2v heads with a shave and a haircut, Performer intake, Holley 650(ish), roller rockers, screw in studs, guideplates, stainless valves, Duraspark / Motorsports MSD, T-5 conversion. 1-1/8" front, 3/4" rear swaybars KYB shocks and some home brewed subframe connectors. Future plans; JGC steering box, Cobra brakes and... paint, interior, etc.

When I die I want to die like grandpa, peacefully in my sleep... not screaming, like his passenger.

[Image: 1_12_09_14_10_15_11.png]
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#7
Three angle valve job is NOT necessary.
Checking the margin on the new (or existing if they're replacement single groove valves) valve/seat interface is more important IMO.
You can remove the carbon with a wire wheel on a bench grinder.
If they're THAT crusty with that low (10K) mileage, do figure out WHY they are so... It would sure make me wonder. Bad seals/guides/ring sealing???

Think of the pushrod question this way:
Using the old pushrods with new rockers is like slipping your feet into someone else's used shoes.
They just don't fit yer feet right.

Same goes for the pushrods. They have a wear pattern into the old rockers already... a pattern that will wear itself into your nice new rockers.

Sure, they'll work, but...

Pete - MotoArts Decals and Signs
'71 Sportsroof 351C-4V/4-speed - FINALLY under construction - no, wait, on hold again...
'90 Mustang 7-Up 5.0 ragtop, rolling beater
'66 Sunbeam Tiger Mk.IA, survivor
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#8
droptop73;105763 Wrote:I would not hesitate to run a good set of 2 piece valves with single groove stems and keepers.

Neither would I. In fact, that is what I have now. Not because I am cheap...well actually it is. It get's back to that a*** thing.

But I won't be blaming anyone else for my decision.

[Image: 11jmcuc.png]
351C Bold Manners, Brash Attitude
Favorite Teams: Michigan Wolverines and Whoever Is Playing Ohio State.

When I drive past a herd of cows, the cows MOO at me
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#9
Dont waste your money replacing head bolts unless they are rusty or damaged.
I have reused hundreds of head bolts and they will be fine, only the newer cars use torque to yield fasteners that are one time use.
You can also reuse the pushrods if money is tight, there are less forgiving things that should be changed.
Do change the valves if they are Ford 2 piece or multi grove keeper style.
Why did the rockers only wear out? Was it tapping or had play on the valves, maybe the cam flattened a lobe, which is more commom these days.
You will need a valve job with the new valves and check or resurface the heads,

[Image: mustangnight010.jpg]
1972 Mustang Convertible 351C 4V
1966 Ford Galaxie 7 litre-4speed

Jorge
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