Got this 1963 Valiant (slant six) a couple of months ago. (Non-running condition, no info on how long its been siting) . . I poured some fresh gas down the carb, and surprise, a got it running while the gas lasted, didn't sound too bad and t didn't smoke. Fast forward to now.... Been cleaning up the motor, and replacing coil, plugs, new points etc. Today, I pulled the valve cover to get a look.
Wow, it looks pretty bad,. Greasy crusty coating all over. Also , a couple of those hex nuts were loose. (problem??) Should I plan on a top end rebuild, clean up the mess and go from there?
Any and all advice is appreciated. Thank you

If it was not smoking and ran OK, then it is not dead ("I'm not dead yet!" - Monty Python).

I recommend checking/raising torque on the head bolts (70 ft lbs) and rocker shaft bolts (40 ft lbs), AND doing a cold/static valve lash adjustment to 0.012" int and 0.022" exhaust. Change the oil (5 qts) and filter to any modern/cheap oil (synth not required, since it will get dirty fast). I recommend a WIX 51515 filter to catch the bad stuff. After that, run it and drive it some and see how it runs. Check oil and when it gets really dirty, change it again.

I have never done an engine oil flush before, but some people like to do that. I feel that any modern oil should free things up and allow you to see where it's at before proceeding.

Lou

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Home of Slant6-powered fun machines since 1988

The crud that you see is due to the engine oils that were available in the 60’s and 70’s.
In the 80’s and continuing to today engine oil additive packages have improved so that with anything near regular/oe recommended oil change intervals, crud like that does not form.
The crud that you see under the valve cover exists throughout that engine, in the oil pan sides of the block… the risk of not addressing it properly is that some of it will break free and potentially clog the oil pick up screen. That would reduce oil flow through the engine and cause damage.
The only way to really address the crud issue is to pull the engine, take it down to the component level, clean the components, hot tank the block and head.
If you pay attention and keep things organized you do not need to spend a lot of money on new components or machine shop work.
I took the OE motor down from the 68 Barracuda, reused pistons, rings, rod and main bearings. Thrashed that motor for a couple of seasons drag racing it. That motor did fine.
I used a ball brush on a hand drill to put the 45 degree cross hatch back on the cylinder bores. Installed new valve springs, valve stem seals, timing chain, cam bushings and a gasket set.
Had the MS hot tank the block and head, cut the head to raise compression and re cut the OE valves and valve seats.
Was careful to get the same rings back on the same pistons and back in the same hole. Rod and main bearings also went back in the location they came from.
The mains and rods were loose to new specifications by a thou or two.
Bores were out of spec for size and taper.
Ran 15w40 diesel motor oil, it ran fine.

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

I agree about the engine oils. Family has been running /6 daily drivers since 1977. The old Quaker State oils gave us your picture. Lost my Quaker State cheap source, so had to go to Costco, selling only Chevron oil at that time. I was surprised that within 2 years of Chevron, no more rotted leaves inside the valve covers. Never had any oil flow problems that I could detect.
I know that OIL is a hot topic to many. But I'm an old guy and stubborn to change, so I have not gone to synthetics in our daily drivers. Currently I'm using Penzoil, with very little particular research on it, other than local price.

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"Louise", a 1976 Dart Custom project, (now sadly reverted to being just an "organ donor" to our other project Darts.)

My ;61 225 is clean, but it still has the original draft tube

My experience is that if you use some sort of snake oil (engine flush, kerosene, etc.) on a sludged up engine, it will clog passages and cause problems. My neighbor destroyed an AMC six like that, and I destroyed a slant and a V8 doing that. My suggestion, as already stated, check the torque on everything, change the oil and filter, and keep on driving. Maybe a frequent oil change interval for a while. But let the modern oil slowly get rid of the sludge, and not all kablam like a flush gives you.

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If it was easy, everybody would be doing it.

I second that - no flush, just put new oil/filter and drive it. You will just have to see what happens.

Lou

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Home of Slant6-powered fun machines since 1988

I've got a friend who decided to treat his daily driver to a synthetic oil change.. Two weeks later the top end is clattering enough to alarm him.. on start up, but it would get quiet as the oil warmed up..

The filter was plugged and going into bypass...

So on a sludgy engine like that, I would use only conventional oil, and keep an eye on the dipstick, for oil viscosity changes.. and maybe use a larger filter?

I guess I'm the lucky one then? I haven't had a problem!