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Need help with parts.

aussiewannabee69

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Have finally ripped the 346 heads off my block that has been sitting quite a while and I need help finding replacement parts.
Before everyone chimes in and tells me I need aluminium heads, I already know that, but I'm lucky to still have this car after my recent divorce. So that being said my original plan has gone out the window for now and I just want to rebuild what I can on this engine to get it going.

It's a1973 block but dated 1972? Is that right?
The intake is a 6 pack.
How do I go about finding the correct stem seals etc. If there's anything I can do to help these heads; I did watch a clip of someone milling the stems down to fit a better type of seal, but that was on 452s. These are 346s. Are they similar?
 
Photos of head and block. Does everything look stock?

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Aluminum heads will always be available and they can be installed in a weekend.
I'm strictly self taught, shade tree, but it looks like it was running good enough to drive around.
 
Looks pretty well stock to me, especially since it is still running steel shim head gaskets. I can't see from the pix, but those look like plain umbrella seals to me... really self explanatory once you get it apart. There are much better options now, but a machinist would need to explain what he can offer. If you are wanting to stay on the cheap, like really on the cheap, you can certainly take it apart yourself, lap in the valves and put new seals on and call it good!! Just look for excess slop, and damaged valves, seats, etc. while you have it down to know if you must go deeper.

BTW, any big block cast iron head is going to be the same scenario when it comes to cutting guides to fit different style seals.
 
Need to pull the heads apart. Get the springs tested along with getting the valves, guides, and seats evaluated. Then the castings should be cleaned along with magnaflux for cracks. Once you have that done you can go from there.
 
Put this in the "it's good info to have later category" Bring a cylinder up to TDC and measure how far down the piston is... You can get surprisingly accurate info by using a feeler gauge and a straight edge.... You should be able to get within a few thousands... Write it down so it's available in the future.....

Looks to me like the springs have been upgraded...

Seals are the same on 356's as a 452.... For what your doing I wouldn't hesitate to put fresh umbrella seals on it....

You should check the guides & do a solvent test to see how the valves are sealing...

Solvent test consists of leveling the chambers and pouring solvent in them to see if they hold or leak.. Hopefully they hold... If not you probably need to address it & then we start talking about cost vs value...
 
Those heads are not the best, it is true. But we get it, often we have to just use what we got. Used sets of the 346 heads go for about $100/pair. Keep this in mind before spending too much on them by taking them to a head shop for service.

I don't believe those heads, OEM, even had stainless valves or hardened valve seats. So if you're going down the road of having work done to these heads, consider buying better heads (906/915) that will flow better, last longer, and (potentially) give you more horsepower.

Valve guide seals are often included in an engine gasket set, so if you're going to be buying the head and intake manifold gaskets as a set, you may be getting the valve guide seals in the kit.

Just about any auto parts store is going to be able to get you the right valve guide seals, if that is all you're replacing. Just the valve guide seals are like... under $10 for a FelPro set. You'll need the spring compressor tool(s) to change them. I don't believe the exhaust valve guide seal is all that critical.
 
Lots of good advice.
The springs and retainers look like decent upgrades.
That coupled with the exhaust ports looking heavily ported, makes a guy think someone was trying to achieve something.
I'd clean up some intake ports and look for signs of porting.
 
Lots of good advice.
The springs and retainers look like decent upgrades.
That coupled with the exhaust ports looking heavily ported, makes a guy think someone was trying to achieve something.
I'd clean up some intake ports and look for signs of porting.
100% Agree... Can't believe I missed that... I saw dirty old castings & made an assumption... We see how that worked out....
 
Lay a straight edge across the valve tips and see if they are even. That is a good sign if the exhaust valves are receding or not. Then solvent test for excessive leaks, lap valves if pretty good. Install new umbrella seals and run them. If you take them to a machine shop I doubt you'll get out of there for less than $500 and I'm not even talking for a valve grind. Shop time costs money and spending money on iron heads is wasting money not spending it.
Most of us learned our lesson on this years ago. I know I did, I hand ported a set of 915's, installed bigger valves etc. and spent more than a new set of Edelbrocks (not what I would choose now) in the end.
 
If you have machinist straight edge, or if you don't, you should solvent clean the heads and take them to a shop and have them at least measure the flatness of the deck surface to make sure you don't have a surface a gasket won't seal.

As Wild said, looks like aftermarket springs and if the guides are not horribly shot, umbrella seals are fine. If the guides are really bad, then no seals will do much good.
 
Put this in the "it's good info to have later category" Bring a cylinder up to TDC and measure how far down the piston is... You can get surprisingly accurate info by using a feeler gauge and a straight edge.... You should be able to get within a few thousands... Write it down so it's available in the future.....

Looks to me like the springs have been upgraded...

Seals are the same on 356's as a 452.... For what your doing I wouldn't hesitate to put fresh umbrella seals on it....

You should check the guides & do a solvent test to see how the valves are sealing...

Solvent test consists of leveling the chambers and pouring solvent in them to see if they hold or leak.. Hopefully they hold... If not you probably need to address it & then we start talking about cost vs value...
Thanks for the info! I will give the solvent test a crack.
 
Lots of good advice.
The springs and retainers look like decent upgrades.
That coupled with the exhaust ports looking heavily ported, makes a guy think someone was trying to achieve something.
I'd clean up some intake ports and look for signs of porting.
Cheers mate. Good eye! Here's another few pics. So I could possibly use the springs again if going well. Does the yellow and blue markings signify anything?
The piston in this pic is at TDC. Looks a long way down?
Oil in one of the intakes. Would that be that part of the head gasket that was leaking?
When turning by hand it still feels like it has decent compression even with one head off. Have to wait till each piston pushes the air through to keep rolling.

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Lots of good advice.
The springs and retainers look like decent upgrades.
That coupled with the exhaust ports looking heavily ported, makes a guy think someone was trying to achieve something.
I'd clean up some intake ports and look for signs of porting.

Yup.
Looks like Crane springs and retainers to me.
 
Bought a valve spring compressor but its worthless. So I ended up making one that actually worked ok. That's the worst of the valves. Only 2 of the valves had a shim between the spring and the head. Are they all meant to have one?

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Looks like some porting done in the intakes. The exhaust valves look rooted. Quite a bit of oil around the intake valves, is that normal?

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Now that I have the heads torn down, can I soak them in vinegar?
I've had really good results with cleaning parts with a vinegar soak.
 
Oil around the intake valves could be seals or guides, but it also could be from the lower intake gasket sucking oil from the valley.
 
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