X Head Assembly & Installation - Comments Requested

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WSUTARD

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As some of you know, I am in the process of a minor rebuild of my 340. The project has turned into something way more than my capabilities but with the help here I have managed to get to the final assembly stage.

I originally thought I had a head gasket leak so I removed my x heads and had them cleaned and checked by my local machine shop. They came back with A+ marks, flat as can be and no cracks.

The heads have the valves still in place but the rockers removed. They were nice enough to tie off the ends of the rocker shaft so all the rockers are in their original place.

I am going to check the block for flatness prior to installing the heads.

I will also check the gasket to the head to ensure no passages are being blocked. Then I am going to place the gasket on the block and then the head.

My first question: The FSM says to coat the gaskets with a sealer. Is this necessary? If so, can I use Permatex Gasket Sealer? I have this already.

Second question: The FSM states 95 ft-lbs as the final torque spec. Is this correct? I know some things were misprinted in the FSM. I understand the torque sequence.

Third question: Are the heads "driver" and "passenger" ? Or does it not matter?

Forth question: I am using a thinner gasket to pump up the compression a little. The new gasket will be about .02 to .03 thinner. Will this force me to make adjustments to the push rods, arms or valves?
 
What head gaskets are you using? Some guys use copper coat, I just had the heads off my 340 and used felpro 1008 gaskets with no copper coat and I have no leaks. I have heard of guys having trouble sealing the thinner mr. gasket 1121's, your deck and heads need to be nice and flat. I was going to use a set but didn't want to chance a leak. 95lbs sounds right to me, I usually do it in stages, 50-70-95. There is no right or left head, they are all the same, your rocker arms do need to be put on correctly though, notch down on both, driver side notch should be pointed toward the front, passenger side notch toward the back. As far as far pushrods being affected by the thinner head gaskets, with that small of a difference, I doubt it but may want to double check.
 
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gtsdude said:
What head gaskets are you using? Some guys use copper coat, I just had the heads off my 340 and used felpro 1008 gaskets with no copper coat and I have no leaks. I have heard of guys having trouble sealing the thinner mr. gasket 1021's, your deck and heads need to be nice and flat. I was going to use a set but didn't want to chance a leak. 95lbs sounds right to me, I usually do it in stages, 50-70-95. There is no right or left head, they are all the same, your rocker arms do need to be put on correctly though, notch down on both, driver side notch should be pointed toward the front, passenger side notch toward the back. As far as far pushrods being affected by the thinner head gaskets, with that small of a difference, I doubt it but may want to double check.
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I plan to use Mr Gasket 1121g because it's thinner. I just checked my deck and it is flat as can be.

Stupidly I order 1 head gasket. Now I have to try to find one locally which will be a pain.

Also, I thought the machine shop would have removed the residual gasket markings but they didn't. Should I work at removing the gasket marks or just not care? I can feel them on the head.
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I have used those gasket numerous time and have never coated them with anything....That FSM is old...Things have changed....Clean the hell out of the block deck and cylinder head surface.
 
70aarcuda said:
I have used those gasket numerous time and have never coated them with anything....That FSM is old...Things have changed....Clean the hell out of the block deck and cylinder head surface.
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Got it. Thanks. Block is clean, will work on cleaning the heads.

I should go back to the machine shop and ask then what I paid for, since the surface isn't clean.
 
I would scrape the heads down. Also anytime i have heads off I give the valves a tuneup/newfie grind to relap them.
Following along with your buold
 
4spdragtop said:
I would scrape the heads down. Also anytime i have heads off I give the valves a tuneup/newfie grind to relap them.
Following along with your buold
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Your going to have to explain what you mean by tuneup/newfie grind.
 
Remove the valve springs and lap the valves to the seats.
Put valve in its orig spot with valve grinding compound and rotate back and forth a few times. Helps seal them up. About an hour labor and $8 valve grinding compound.
You can use a drill in the retainer end of the valve. Check out youtube. Better description there lol.
WSUTARD said:
Your going to have to explain what you mean by tuneup/newfie grind.
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Looking at your heads they are a little rough on the last mill job, take your finger nail and run it over your head surface and see if you feel the bumps in the grind marks. I have a milled flat piece of aluminum that I put a sticky back DA disk on and run it over the head. Start with 220 and you will see the high spots then finish with 320, just makes it better for the thinner gaskets. I also use copper coat on the thin gaskets and the MLS gaskets.
 
Oh ya, don't use a stiff wire wheel it cuts the metal!
 
brian6pac said:
Looking at your heads they are a little rough on the last mill job, take your finger nail and run it over your head surface and see if you feel the bumps in the grind marks. I have a milled flat piece of aluminum that I put a sticky back DA disk on and run it over the head. Start with 220 and you will see the high spots then finish with 320, just makes it better for the thinner gaskets. I also use copper coat on the thin gaskets and the MLS gaskets.
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Yep, I can feel the ridges. Guessing it isn't supposed to be that way. Darn, more work.
 
WSUTARD said:
My first question: The FSM says to coat the gaskets with a sealer. Is this necessary? If so, can I use Permatex Gasket Sealer? I have this already.

Second question: The FSM states 95 ft-lbs as the final torque spec. Is this correct? I know some things were misprinted in the FSM. I understand the torque sequence.

Third question: Are the heads "driver" and "passenger" ? Or does it not matter?

Forth question: I am using a thinner gasket to pump up the compression a little. The new gasket will be about .02 to .03 thinner. Will this force me to make adjustments to the push rods, arms or valves?
Click to expand...

Current gasket tech has no need for coating them unless there a copper or bear steel.

95 ft. pounds sound right. Do it in 3 steps. 79-80-95.

The heads are interchangeable from side to side, as well as the gaskets.

No adjustments needed with a Hyd. Cam. The Hyd. lifter is designed to be flexable like this.
 
WSUTARD said:
Yep, I can feel the ridges. Guessing it isn't supposed to be that way. Darn, more work.
Click to expand...
If you do like brian6pac said, then you need a known very flat and stiff piece of metal to use as a backer for the sandpaper. Sanding without this can result in more low and high spots than you started with; without it, you have no control where the sandpaper is digging in. Having tiny ridges like what appears i the pix is not a big issue on this level of rebuild IMHO; heads seal up well all the time with tiny ridges on the surfaces. Head and block flatness are the first and biggest concern for you. (Which is what I think brian6pac was really getting at, with looking for high spots.)

If you use a gasket sealer, what you show in the original post is not what you want. You want a can of spray-on Copper-Coat. The 1121G gasket has a sealing surface on it, so you should be good without sealer, but it won't hurt to add a very even, light coat of Copper-Coat.
 
Do you know how many times the head bolts have been reused, retorqued ? They do fatigue. New head bolts might be a wise investment.
All too often what was thought to be a head gasket water leak turns out to be a intake gasket failure ( although you didn't say water leak ).
Minor head milling effects intake gasket fitment and we don't know how much milling has been done to antique heads. Aftermarket aluminum intakes may add to the misfit, possible gasket failure. So... Pay just as much attention to the intake gasket choice and fitment, as the head gaskets. Good luck with it.
 
nm9stheham said:
If you do like brian6pac said, then you need a known very flat and stiff piece of metal to use as a backer for the sandpaper. Sanding without this can result in more low and high spots than you started with; without it, you have no control where the sandpaper is digging in. Having tiny ridges like what appears i the pix is not a big issue on this level of rebuild IMHO; heads seal up well all the time with tiny ridges on the surfaces. Head and block flatness are the first and biggest concern for you. (Which is what I think brian6pac was really getting at, with looking for high spots.)

If you use a gasket sealer, what you show in the original post is not what you want. You want a can of spray-on Copper-Coat. The 1121G gasket has a sealing surface on it, so you should be good without sealer, but it won't hurt to add a very even, light coat of Copper-Coat.
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I was going to use a sander like this. 17 in. Auto Body Hand Sander

However, I would rather not if I don't have to.

I'm waiting on the second 1121g to arrive so I have some time anyway.
 
You don't want some thing with a soft back, you need something solid so it will knock off the high spots. Just a light pressure and good paper and the high spots show up and It does not have to be super smooth. It's more critical on a aluminum head as they expand more and if it has a rough surface it will wear out the gasket.
 
WSUTARD said:
For intake I am using Fel-Pro 1213. Fel-Pro 1213 Intake Manifold Gasket Set https://www.amazon.com/dp/B000CNNHQ4/ref=cm_sw_r_cp_api_ylu2ybEEJW6YW

Is there something better?

I don't mind getting new bolts. Can I use grade 8 for a place lice fastenal?
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Although that link didn't work.. I do like the Felpro print-a-seal gaskets. I add RTV in some places like at the 4 corner water ports. I couldn't buy gaskets through Amazon, ebay or any mail order. Who knows what quality I might receive. If I buy from a local part store I at least know they were properly stored and handled. Some online sellers may have ancient stock stored in mini warehouses, poorly stacked, walked on, who knows?
As for head bolts... I buy a set of head bolts, Summit, Jegs, RockAuto, wherever is the best price. I don't expect hard parts like bolts to arrive damaged.
 
Being they are graphite gaskets dont use any sealer just clean surface with brake clean dont go sanding.Also the clean valves in the first cyl is that from cleaning or did it come off that way? Being that clean thats possible where the water leak was. Is there a chamber on both sides that clean?
 
joec said:
Being they are graphite gaskets dont use any sealer just clean surface with brake clean dont go sanding.Also the clean valves in the first cyl is that from cleaning or did it come off that way? Being that clean thats possible where the water leak was. Is there a chamber on both sides that clean?
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Not sure what you are referencing in the pics. All the valves are identical in person. Here is what they used to look like.
IMG_1368.JPG
 
Usually the cyl that leaks water will be cleaner than the rest . Water is a good carbon remover.In the picture the third from the right looks kind of different but cant really tell.Notice the exh valve.
 
WSUTARD said:
I don't mind getting new bolts. Can I use grade 8 for a place lice fastenal?
Click to expand...
No get the proper head bolts. The shanks have specific shapes. There is one head bolt hole on each side that has to have a narrowed shank to make sure the proper oil flow gets to the head; that flow actually goes around the shank of that specific head bolt in each head on its way to the rocker shaft.
 
When the local shop inspected your heads, did they say anything about the surface roughness? If not, I personally would not bother. There is a certain range of average roughness (Ra) that is acceptable. (For example, 60 to 100 is the range recommended by Felpro for their Permatorque on iron heads.)

I bet some guys here could run their thumbnail over the surface and get an idea of the Ra from long experience. (But I know I couldn't.) It is about impossible to assess simply from an internet pix.
 
nm9stheham said:
No get the proper head bolts. The shanks have specific shapes. There is one head bolt hole on each side that has to have a narrowed shank to make sure the proper oil flow gets to the head; that flow actually goes around the shank of that specific head bolt in each head on its way to the rocker shaft.
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$80+ for bolts? Am I finding the correct ones? Head Studs / Bolts / Washers or http://www.classicindustries.com/product/mopar/parts/mn2088.html/

nm9stheham said:
When the local shop inspected your heads, did they say anything about the surface roughness? If not, I personally would not bother. There is a certain range of average roughness (Ra) that is acceptable. (For example, 60 to 100 is the range recommended by Felpro for their Permatorque on iron heads.)

I bet some guys here could run their thumbnail over the surface and get an idea of the Ra from long experience. (But I know I couldn't.) It is about impossible to assess simply from an internet pix.
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They said the heads were in A+ shape. I didn't inquire further. The shop is well known around here for quality work so I trust their judgement. I just wish that "cleaning the heads" to them meant clean up the mating surface.
 
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