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Head Gasket leak

73-Cudah2

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Well after doing some digging around I found that the exhaust valve is made like that. I think I will still send the heads in and have them check them over for a crack / surface level and valve job if the other 2 check out ok.

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73-Cudah2

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I have been looking around in Minnesota for a engine machine shop. Does anyone have a place in Minnesota
they recommend or they have used? Thanks.
 

73-Cudah2

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Can someone tell me if 340 OEM valve covers fit all 340's up to 69-73 Cuda?

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Xcudame

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All small block LA valve covers will fit all LA small blocks. So you're good to go even if they're not 100% restoration correct.
 

73-Cudah2

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Thank you Xcudame. Not sure I'll use them I'm still looking for the correct year for the 340.
 

73-Cudah2

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I have another question for the 1973 Cuda 340. I am going to replace the valve seals
and pulled off the old ones but can't seem to find the exact make of the ones I have.
there is a small spring on the bottom side around the valve guide for both intake and exhaust ones and a small sleeve around the valve it self.

One kit I saw had 2 different types one for exhaust and one for intake? Thank confused me. Are they different valve stem seals on the 1973 340?

Here are some pictures on the #1 cylinder exhaust and intake they are all the same.
The online order ones look different for intake? they don't seem to fit around the valve guide like the exhaust ones?
Thanks for your reply's.

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73-Cudah2

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I did have the heads Magnaflux tested they are good also for compression. I think the problem was the water passage through the timing chain cover. The fuel pump opening was thick coolant but that was the only location of that. I ended up buying a new timing cover.
 

Xcudame

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The valve seals you removed are not stock. Look kinda like Mahle/Clevite seals. The replacement set look like the typical sets you get. the little umbrella seals go on the exhaust valves and the "bigger" ones go on the intake valves. The idea is you want a little oil on the exhaust valve as they get much hotter which is why those seals are a little smaller in height.
 

73-Cudah2

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Thanks JDmopar yes I ended up getting positive vitron seals for all. I have another question if anyone knows. I did a manual lap on all the valves. does anyone know where specs are for
the seat width for intake and exhaust? 30, 45, 60 degree faces.

Thanks for your help!

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73-Cudah2

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I decided to buy valve cutting tools.
will be doing all exhaust and intakes on each head. and lap valves. I found out that I need .080 to .105 seats for intake and .090 - .110 exhaust seats. so I will be working on that. I have also been chasing treads and black Oxide most of the external bolts after cleaning them up. I also picked up from New Way 3 Pilots 3/8 std +1 and -1 the -1 works in my 340 (360) heads. I also ordered Black Oxide for my bolts works great.

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73-Cudah2

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I started to reassemble the 340, I ended up having the heads done they needed a lot of work.
new springs, face cut, valves triple ground.
Installing oil pump and windage tray. Next is the oil pan.
Question: Do you put RTV in the slot end rubber caskets? I have seen some videos that do.
mine didn't have any RTV on them.
I still have to remove carb and clean and paint the intake.
I also have 4 position on the for the pulley to fit on the harmonic balancer. The screws fit in these
(marked by silver lines that line up with Key in crank) with no issue. Does anyone see a problem if not in the original position?
Thanks for your input.

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Xcudame

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Yes, put RTV on the ends of the rubber gaskets. Most will be squished out, but it will help prevent oil leaks! Mopars can be made not to leak oil much easier than Shivvies and Phords! 😀
 

JDMopar

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I put Ultra Black under the entire surface of the gasket, in between the rubber gaskets and the pan where they seal. I make sure to get plenty under the corners at the top of the U. Just try not to goop too much real close to the holes in the pan where the nubs on the gasket poke thru the pan. If you get it on the tips of the nubs as they start thru the holes, it makes them too slippery to grab them with pliers to pop them in deep enough to seat. Check your gaskets and pan to see if the pan/gasket has a larger indention for the square part of the gasket to rest in. If so, make sure to turn the gasket accordingly.
 

Ricks72Chlgr440

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I started to reassemble the 340, I ended up having the heads done they needed a lot of work.
new springs, face cut, valves triple ground.
Installing oil pump and windage tray. Next is the oil pan.
Question: Do you put RTV in the slot end rubber caskets? I have seen some videos that do.
mine didn't have any RTV on them.
I still have to remove carb and clean and paint the intake.
I also have 4 position on the for the pulley to fit on the harmonic balancer. The screws fit in these
(marked by silver lines that line up with Key in crank) with no issue. Does anyone see a problem if not in the original position?
Thanks for your input.

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Lookin good! I absolutely love the old thermoquad carbs. Think you'll have a great running engine for many years.
 

73-Cudah2

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Question on Harmonic Damper touching the timing cover? Do you think is will move once it's warmed up
running the engine? I mean the rubber between the 2 parts to straighten it out? It looks like one side is in a little to the timing marks and the rotate it and the other side ( 180 degrees ) it's out from the timing marks ( See Pictures ).
The Damper has a few cracks in the rubber that I can see from that back, should it be replaced/Rebuilt?
The Damper key and timing mark are still true with each other.
Thank you for your input.

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Ricks72Chlgr440

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Question on Harmonic Damper touching the timing cover? Do you think is will move once it's warmed up
running the engine? I mean the rubber between the 2 parts to straighten it out? It looks like one side is in a little to the timing marks and the rotate it and the other side ( 180 degrees ) it's out from the timing marks ( See Pictures ).
The Damper has a few cracks in the rubber that I can see from that back, should it be replaced/Rebuilt?
The Damper key and timing mark are still true with each other.
Thank you for your input.

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I would replace the damper. I don't believe they can be rebuilt. The rubber goes bad after so many years and can cause issues. Better to do it now while you're doing your work on the engine.
 
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