Troubleshooting Head Components

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zmarty27

zmarty27

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Hey gang,

Long story short, I took the head off to change the gasket in order to fix a problematic oil leak. Based on the stamped steel gasket, I don’t think this engine has ever been serviced since its birth in ‘74. As you can see, it’s been running hot for years. I finally got that problem under control prior to head removal. Should I go ahead and buy replacement valves? They look awfully spent to me. Second question is this: upon removal, residual coolant escaped into the block, held in place by the piston. It wasn’t a lot, but certainly enough to worry me. I assume it’ll just smoke like hell for a bit until it’s burned off, right? That’s what I read on the forum, anyway. Anyhow, let me know what you guys think. Manuals and YouTube are only getting me so far. Human interaction is this missing link for me. Thanks!

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I would say a valve-job is in order, & new valves/reconditioned guides as needed, I do NOT mean knurling the guides BTW.
While You're at it, get the head milled .040", that'll recover the extra thickness of the new head gasket(unless You have a new shim one) + bump it closer to where it shoulda been stock. Don't forget to back the rocker adj screws off about a turn, go from there when You've got it together.
Coolant, sop out what You can with paper towels as soon as You can, I usually turn the engine a few times re-wiping the cyl walls each time.
P.S. Always always always check the oil feed hole from the deck up, & from the rear rocker pedestal down, clear & clean w/solvent & compressed air if needed.
 
Head diagnostics would vary by member wouldn't it? (The /6 would have nothing to do with it)

Besides that I'd pull the valves and look at the overall condition of them, you can't see the sealing face or much of the stems while still in the head. And then maybe not til you start trying to machine them on a valve grinder (though more experienced machinists can tell more by just looking at them as to whether they're reusable.)
For the experience I'd pull them, and either bead blast them or run them on a wire wheel for starters and then go from there
 
If you put a nice refurbished head on top of an old bottom end, you run an elevated risk of the engine quickly turning into a heavy smoker (good-sealing head pulls oil past worn rings) and/or finishing off the old bearings in short order. How much of an elevated risk depends on how much wear/how many miles on the bottom end.
 
slantsixdan said:
If you put a nice refurbished head on top of an old bottom end, you run an elevated risk of the engine quickly turning into a heavy smoker (good-sealing head pulls oil past worn rings) and/or finishing off the old bearings in short order. How much of an elevated risk depends on how much wear/how many miles on the bottom end.
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So is there a win in this situation without yanking out the whole motor? I don’t have that time or that money. I just wanted to replace a gasket for Pete’s sake. Lol
 
zmarty27 said:
So is there a win in this situation without yanking out the whole motor? I don’t have that time or that money. I just wanted to replace a gasket for Pete’s sake. Lol
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Chock up the head level, fill each chamber with trans fluid or kerosine, if it leaks past pretty fast, I`d get a valve job done.
I had a high milage engine that needed a valve job, that car went on for another close to another 100k miles on the stock bottom end, and it was a Pinto for crise sakes :rolleyes: :lol:
 
Well, how many miles on this motor? Honestly if it ran fine except for the bum gasket, there's no hard evidence of broken/worn-out parts, and you don't want to do a full rebuild, just clean things up and put them back together.
 
slantsixdan said:
Well, how many miles on this motor? Honestly if it ran fine except for the bum gasket, there's no hard evidence of broken/worn-out parts, and you don't want to do a full rebuild, just clean things up and put them back together.
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It claims 67k, but I’m willing to bet it’s 167k based upon the wear. Besides a timing issue, it ran well. I haven’t removed the springs yet to see how the seals are faring. I had planned on cleaning and lapping the valves since it’s undeniable they need attention. I considered porting, but I’m still reading up on it all.
 
Id replaced those seals no matter what as a bare minimum as they are cheap, not hard to do, and well, you have the dang head off in your hands.
I rarely pull a head and "not" send it thru a machine shop. I'm not saying I have a competition valve job and full port and polish done, but definitely a basic valve job and check for warp at a minimum. Pretty much automatic.
 
volaredon said:
Id replaced those seals no matter what as a bare minimum as they are cheap, not hard to do, and well, you have the dang head off in your hands.
I rarely pull a head and "not" send it thru a machine shop. I'm not saying I have a competition valve job and full port and polish done, but definitely a basic valve job and check for warp at a minimum. Pretty much automatic.
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Kind of my thought on the matter, however, I didn’t know if that would have negative consequences considering I’m not toying with the block/pistons/rings/etc. Curious to know if there is a part number for those seals? I’ve got a parts manual from eBay, but some chunks are missing. I saw on the other forum that parts numbers for a post-‘74 head are listed, but not pre-‘75.
 
Sealed power, fel pro, victor reinz all will have those seals. I doubt they will still be available from Mopar, and if they were they're probably 30+ years old and brittle from being on the shelf so long. Replacing valve guide seals will have no effect on compression or aggravating worn cylinders or rings, etc. a lot of how it turns out (fresh valve job on top of old short block) actually has more to do with how well everything waa maintained prior to this point and how it was treated in the miles it has accumulated than how many miles, etc. just because it has *** number of miles really has little bearing on the situation. How clean (relatively speaking) was the engine when you pulled the head? Ring ridge (behind any ridge that may simply be built up carbon? Score marks up n down cylinders? Any cross hatch still visible? ( Might have to look hard to see)
The most likely engine to all of a sudden start eating oil after a head refresh are those that obviously weren't very well taken care of, heads so full of sludge you can't see the drain back holes for starters, would be a sign that refreshing the head or even just the gasket, without going deeper at the same time.
 
The valve guide seals that fit your engine will actually fit many. There are many engines of all brands that had 3/8 diameter valve stems ...
 
volaredon said:
Sealed power, fel pro, victor reinz all will have those seals. I doubt they will still be available from Mopar, and if they were they're probably 30+ years old and brittle from being on the shelf so long. Replacing valve guide seals will have no effect on compression or aggravating worn cylinders or rings, etc. a lot of how it turns out (fresh valve job on top of old short block) actually has more to do with how well everything waa maintained prior to this point and how it was treated in the miles it has accumulated than how many miles, etc. just because it has *** number of miles really has little bearing on the situation. How clean (relatively speaking) was the engine when you pulled the head? Ring ridge (behind any ridge that may simply be built up carbon? Score marks up n down cylinders? Any cross hatch still visible? ( Might have to look hard to see)
The most likely engine to all of a sudden start eating oil after a head refresh are those that obviously weren't very well taken care of, heads so full of sludge you can't see the drain back holes for starters, would be a sign that refreshing the head or even just the gasket, without going deeper at the same time.
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As you see, the sludge is rather tremendous, but that is apparently a common denominator for many slant owners I’ve come to find out. Lol The same amount of carbon was found on the pistons, but the rings seemed to be in rather good shape.

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That's actually a light layer of sludge. Not too bad, really. With all the work involved, there's no way I'd put that head back on without having it fully reconditioned, including having it milled. I agree about not having the guides knurled. That's a quick fix that really doesn't last any time at all. It'll likely need new guides and maybe even some valves and possibly some seats. Or, you could just slap it back together like Dan said. But then you will have fixed nothing. Your call.
 
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Oh and the coolant leaking into the cylinders when removing the head is perfectly normal. Since the head gasket seals coolant from entering the cylinders, you breach that seal when you remove the head.
 
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Progress so far. Soaking the head today and sending it to the shop sometime this week. Eventually, I’ll give the pistons some TLC.
 
I agree light sludge. Diesel oil is high in detergents. I run that in my cars. Rotella semi-synthetic. Had the intake off my '97 Lesabre a couple of weeks ago. I could see the valve stems. Clean like new. 230K+ on it. Really clean every where else.
 
zmarty27 said:
It claims 67k, but I’m willing to bet it’s 167k based upon the wear. Besides a timing issue, it ran well. I haven’t removed the springs yet to see how the seals are faring. I had planned on cleaning and lapping the valves since it’s undeniable they need attention. I considered porting, but I’m still reading up on it all.
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zmarty27 said:
You guys are awesome. Thanks for all the advice!
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Not that my opinion matters at all since you already have a plan, but just basically wanting to solve the immediate problem without going into a big job I think your thoughts on lapping the valves and replacing stem seals is a good plan.
During that you can decide if it needs more.

Did you ever hear the joke about the guy that took Carters Little Liver pills his whole life?

When he eventually died they had to beat his liver to death with a stick.

That is what spending the money to do a complete head refurbish on that motor reminds me of. :D
 
TrailBeast said:
Not that my opinion matters at all since you already have a plan, but just basically wanting to solve the immediate problem without going into a big job I think your thoughts on lapping the valves and replacing stem seals is a good plan.
During that you can decide if it needs more.

Did you ever hear the joke about the guy that took Carters Little Liver pills his whole life?

When he eventually died they had to beat his liver to death with a stick.

That is what spending the money to do a complete head refurbish on that motor reminds me of. :D
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Mopars have soft valve guides. Mic the stems, then mic the guides. I would really have the guides replaced without all the measuring.
 
Rug_Trucker said:
Mopars have soft valve guides. Mic the stems, then mic the guides. I would really have the guides replaced without all the measuring.
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And then he is in for a valve job.
Both requiring machine shop labor.
At that point might as well get the head resurfaced while it’s there.

I thought he was asking if he could avoid all that cost.

From the looks of the valve and chamber colors, I think he can.
Especially since the rest of the motor is over 100k.
 
If that was in my shop, I'd position the pistons in a manner to be able to pour an inch or little more of clean solvent in each cylinder.
See how long it takes to drain a cylinder.
I wouldn't be surprised if one or two of those lost fluid very quickly, and some way later, some may hold fluid till next day.
Compression test of sorts.
If all are fairly even after a while, hours/overnite, send it.
Draw your own conclusion .
 
inertia said:
If that was in my shop, I'd position the pistons in a manner to be able to pour an inch or little more of clean solvent in each cylinder.
See how long it takes to drain a cylinder.
I wouldn't be surprised if one or two of those lost fluid very quickly, and some way later, some may hold fluid till next day.
Compression test of sorts.
If all are fairly even after a while, hours/overnite, send it.
Draw your own conclusion .
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Would the block deck need to be level so to test the entire circumference?
 
No, I do it on V-8s as well.

Rug_Trucker said:
Would the block deck need to be level so to test the entire circumference?
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It's just to get an idea of ring seal while your doing other stuff.
If you get one that disappears quickly, it's near impossible to do them all at once, so rotate and refill, just noting as you go by.
Ideally they'll hold fluid evenly for a good long while.
If one or 2 disappear, the rest holding, there a good bet it has a broken ring or similar, and let customer know to make a decision.
Nothing worse than doing valve grind, ( which is common at 60k+ miles ) just to put head back on and have it smoke .
It's better to be able to fore-warn with a reason, than look a fool making excuses afterwards.
It was just a habit that proved worthwhile many times over, and often was a broken ring.
Spark plugs should have forwarned anyway.
Mentor taught me that, by the way , I pass that to you .
Thnx Ed, for many things .
 
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