Healthy Head?

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morsim

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Exhaust was blowin' white (& maybe slight light blue). Thought it might be blown head gasket - but it looks fine.
Found two bend push rods upon taking off valve cover.
What's the next step here? Anything look immediately wrong with this here engine? If not, what's the next step, and if yes, ditto. :)

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Total cleanup and check block for flatness. Take the head to the machine shop and have cleaned, flatness checked and get a valve job. Check spring pressures and valve guides.
 
So Ima guessing you didn't do a cooling system pressure test, nor a compression test, nor a leakdown test .
In which case, I for one can't help you.
At this point, I think you kindof shot yourself in the foot. IDK how you can pressure-test the block, in-frame. Send the head out for a pressure test but if it come back A-ok, Ima guessing the engine will need to come out for further testing.
The two bent pushrods are pointing to valves stuck in the guides, so the head is gonna need work ..... if it passes the pressure test.

I hope you are aware that the products of combustion are energy and water, so under certain circumstances, seeing steam, white-smoke, or even water dripping out of the tail pipe is normal.
 
Take a fingernail and scrape it up the side of the cylinders all the way out the top. If you can catch your fingernail on the ridge at the top, the bore is worn enough it needs boring. If you can catch your nail on the ridge really BAD, it's wore slam out, and while rebuilding the head will help "a little" you'll basically be throwing money in the fire without seeing to the short block.
 
ch1ll said:
Total cleanup and check block for flatness. Take the head to the machine shop and have cleaned, flatness checked and get a valve job. Check spring pressures and valve guides.
Click to expand...
Thanks. Gonna bring it over to the machine shop tomorrow.

RustyRatRod said:
Take a fingernail and scrape it up the side of the cylinders all the way out the top. If you can catch your fingernail on the ridge at the top, the bore is worn enough it needs boring. If you can catch your nail on the ridge really BAD, it's wore slam out, and while rebuilding the head will help "a little" you'll basically be throwing money in the fire without seeing to the short block.
Click to expand...
I gotta say it looks worse than reality in the images. Fingernail test proved alright for most cylinders. Got some more buildup at the ridge of cylinder #3 than the others but even so, while it does catch, it's relatively easy to scrape by...
How's about cleaning the innards of the cylinders themselves? Got a whole bunch of free floating carbon excess & coolant in there (that I'm hoping just spilled in while removing head)...

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Soak the coolant up with paper towels the best you can. Leave the carbon be.

Can you see cross hatching from honing in the cylinders?

How many miles on that engine?
 
ch1ll said:
Soak the coolant up with paper towels the best you can. Leave the carbon be.

Can you see cross hatching from honing in the cylinders?

How many miles on that engine?
Click to expand...
It's loose carbon though.
Will check for cross hatching tomorrow.
About 75k mi on the engine.
 
morsim said:
Thanks. Gonna bring it over to the machine shop tomorrow.


I gotta say it looks worse than reality in the images. Fingernail test proved alright for most cylinders. Got some more buildup at the ridge of cylinder #3 than the others but even so, while it does catch, it's relatively easy to scrape by...
How's about cleaning the innards of the cylinders themselves? Got a whole bunch of free floating carbon excess & coolant in there (that I'm hoping just spilled in while removing head)...

View attachment 1716294782

View attachment 1716294783
Click to expand...
Yes, the carbon buildup always makes it look bad.
 
ch1ll said:
Soak the coolant up with paper towels the best you can. Leave the carbon be.

Can you see cross hatching from honing in the cylinders?

How many miles on that engine?
Click to expand...
Here's a peek inside + a quick cleanup view of all cylinders

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Hard to tell in those pictures. You definitely need to make sure the deck is flat and clean out the tapped holes.
 
Is it safe to spray brake cleaner into the cylinders and use compressed air to blow out all the loose crap near the ringlands? Or is that a no-no since it risks just pushing things deeper into there..?
 
Looks and sounds like the head wants enough work that you'll want it properly rebuilt, including guides and hard exhaust seats. Careful-careful; putting a nice, good-sealing head atop an old bottom end is a sure-fire recipe for an oil burner de luxe (pulls oil past worn rings/bore), and this engine was already beginning to smoke, so you'd be smart to refurbish the whole engine. This will involve the usual thorough cleaning (inside and out—there's probably quite a bit of rust and mud in the coolant passages) and extensive careful measurement to determine what-all is needed to bring it up to snuff.

There is a great deal of low-hanging fruit in the form of parts and assembly tricks and techniques to wind up with a better result. For example, the camshaft and its bearings are wear items, so take the opportunity to get a № 2106R camshaft from Oregon Cam—that's the Dutra RV-10RDP, which brings a really nice improvement in driveability on a street-driven car without the drawbacks and hassles of most of the more widely advertised "upgrade" cams for the Slant-6. You'll find plenty of build and parts advice here and on slantsix.org.
 
@slantsixdan got er back from the shop. Opted not to do a full head rebuilt since I'm on a tight money & time budget and because there wasn't any overheating I'm gonna take the gamble for now and stick w/ the old block... We'll get em another time (hopefully won't need to tho :thumbsup:)

Now, head's back on after some fighting to seat it both sides down properly. Whew.
Next I plan to put the rocker back on tomorrow and test her out.
How should I be ensuring the rocker (and it's associated components) are properly lubed for the first post-"rebuild" dry run since the valve cover will be off for testing?
 
So what all was done to the head?
 
RustyRatRod said:
So what all was done to the head?
Click to expand...
Cleaned by the shop and apparently painted blue? Unless that's the original paint... Possibly resurfaced since it is clean although wasn't shiny.
Did a visual on valve seals and nothing seems cracked at first glance, though I've seen videos of people changing those seals with the head attached - so I figure it's not time sensitive. Just wanted to get the head back on in my time crunch...


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No, it hasn't been surfaced. Good luck with it.
 
morsim said:
:eek: thx. Will need it.


Whatcha say?
Click to expand...
Pour some STP oil treatment on everything up top. I don't understand what you're expecting to change, because you haven't changed a thing. A lot of work for nothing.
 
morsim said:
@slantsixdanOpted not to do a full head rebuilt (…) because there wasn't any overheating
Click to expand...

Err…huh? The one doesn't follow from the other.


morsim said:
How should I be ensuring the rocker (and it's associated components) are properly lubed for the first post-"rebuild" dry run
Click to expand...

This is not a thing you have to worry about. Just start the engine and watch for oil to be dribbling out the nose of each rocker arm within a short time after startup. If not, things weren't cleaned up enough when the head was off.

Do not purchase STP oil "treatment" or any other such goo. It is unnecessary and not beneficial in any way; all it does is waste your money.

Did a visual on valve seals and nothing seems cracked
Click to expand...
They easily stop doing their job without visible cracks.

people changing those seals with the head attached
Click to expand...
The easy way is described here.
 
Wow, quite comprehensive. Thank you Dan. I will report back after following your process.
 
junkyardhero said:
did you ever ascertain *why* the two pushrods were bent?
Click to expand...
Negative. Although I did notice that after coming back from the shop (forgot to test before), most of the valve springs were (with two-thumbed effort) compressible by hand - except the ones that had bent pushrods attached to em (+ a couple others that I may have just not pressed hard enough on)... Go figure!

If I'm not mistaken, I see that the process in Dan's guide should fix stuck valves too, so I'll have to try it out.
 
Hmm thinking back, I did the thumb pushdown test from the side top part of the spring and not from the little round metal part where the rocker arm meets, so maybe my test didn't actually tell much...
Being my first rodeo I'm really a bit clueless on testing. Would love to hear your input.

P.S. I wasn't actually getting any symptoms of bad valve seals to begin with which is why I decided not to pay much attention to it while I had the head off. It was not blowing the smoke on deceleration or on initial start (see my other post).
 
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