Valve Stem Seals or Something More?

[pa383mopar]

I am in need of some advice on '67 383 4BBL fully rebuilt 15 years ago with approximately 30,000 since rebuild.

I am seeing a good amount of blue smoke upon startup and lesser amounts of blue smoke until the engine is warm. Once the engine is warm, I don't see any smoke.

I assumed valve stem seals when I saw the smoke on startup, but I am wondering if the seals would also cause smoking until the engine is warmed up. I should also mention that I am hearing a mild knocking (lower pitch sound than lifters) when the car is first started until it is running for about 3 minutes or so. I have looked through as many posts as I could find on the topic as well as other sources. The knocking has led me to discussions on "piston slap" etc. (rebuild included Keith Black hypereutectic forged pistons). I'm not sure if the knocking and smoke issues are related or not. I haven't done a compression test yet, though I understand is may be a good next step. Any and all thoughts and suggestions are appreciated. Thanks in advance.

 

[turbine68rt]

I'm guessing the valve guides themselves could be worn. Btw, your car is one of my all-time favorites whenever I go to Carlisle. Love the color.

 

[oldbee]

Yup, could very well be worn valve guides. Maybe, no bronze inserts were added?

 

[dvw]

I'd swap the seals. Cheap. Not to hard to do in the car.
Doug

 

[R413]

Between wax jobs, nice car!

 

[khryslerkid]

Easy enough to remove a valve cover and inspect the seals. If they are bad it's easy enough to replace them or make the decision to remove the heads and freshen them up. Good luck, nice ride!

 

[66Satellite47]

My '70 383 daily driver was using oil. The dealer replaced the cracked valve seals at 49,500 miles. It helped a lot. But I'm sure the guides would have needed to be done too.

 

[Jerry Hall]

Valve guide seals were a major issue on my original 67 383 Satellite between 67-69. In 69 the dealership actually pulled the heads under the 5 year 50K mile warranty and completely went through them. That was after 3 sets of valve guide seals done without pulling the heads. The original 516 heads were very hard on the seals and wear on the guides. I'm sure my driving habits at 20-21 years old may have been a contributing factor. Tires and valve seals wore about equally.

 

[Don Frelier]

I have hypereutectic pistons in my charger. 25 years old with 30k on it and it's quiet. They aren't noisy like a forged piston. I would suspect something else.

 

[pa383mopar]

Thanks everyone for the suggestions and complements, all are much appreciated.

Do you think the knocking I am hearing when the engine is cold may be related to worn valve guides?

 

[slimt]

Nice Coronet.

 

[slimt]

Thanks everyone for the suggestions and complements, all are much appreciated.

Do you think the knocking I am hearing when the engine is cold may be related to worn valve guides?

I would be looking at a rebuild. Knocking could be wrist pins to rod bearings
Im in the process of redoing the block on mine. Heads are fresh. I figured the heads would correct the issue. In my case. No. Rebuild time.

 

[dadsbee]

Knocking or an exhaust leak that seals itself when the manifolds heat up and expands...

 

[Geoff 2]

I would have thought that if the valve guides are worn, the smoke would get worse, not less, once the engine warms up, because the oil gets thinner with heat & is more easily drawn past the guides.

I would be looking at broken top rings because of insufficient end gap with hypereutectic pistons. But change valve seals first, that is easy.

 

[Mopar Hunter]

My 383 did the same thing on start up, it would burn blue smoke. I removed a valve cover and notice some plastic pieces on the top of the head. I used the rope method and a spring compressor and replaced each of my seals, no more smoke. Not too bad of a job, took me a couple hours for each side.

What weight of oil are you using? When I change my oil for the first after I got my Charger, I used a 50 weight and it knocked. I changed back to the 30 weight and the knocking went away. I’m thinking mine was a lifter tick.

 

[pa383mopar]

My 383 did the same thing on start up, it would burn blue smoke. I removed a valve cover and notice some plastic pieces on the top of the head. I used the rope method and a spring compressor and replaced each of my seals, no more smoke. Not too bad of a job, took me a couple hours for each side.

What weight of oil are you using? When I change my oil for the first after I got my Charger, I used a 50 weight and it knocked. I changed back to the 30 weight and the knocking went away. I’m thinking mine was a lifter tick.

Oil is 10w-30, changed annually with about 2,000 driven per year. The knocking only occurs during the first few minutes after starting cold. Once the engine is warm the knocking disappears. The car runs great otherwise.

 

[MarPar]

Oil is 10w-30, changed annually with about 2,000 driven per year. The knocking only occurs during the first few minutes after starting cold. Once the engine is warm the knocking disappears. The car runs great otherwise.

Lifter pumping up after warm. My 383 Newport does the same thing.

 

[Geoff 2]

[1] Hypereuctic pistons are NOT forged, they are cast.
[2] They are also tight fitted to the bore, piston slap should not occur.
[3] As stated in post #14, noisy piston are likely to be piston damage problem/broken rings, a common problem with HE pistons because builders fail to use the required larger ring gap with the top ring.

 

[pa383mopar]

[1] Hypereuctic pistons are NOT forged, they are cast.
[2] They are also tight fitted to the bore, piston slap should not occur.
[3] As stated in post #14, noisy piston are likely to be piston damage problem/broken rings, a common problem with HE pistons because builders fail to use the required larger ring gap with the top ring.

Thanks Geoff.
You are correct, they are cast, I knew that, yet in my op I typed forged, my mistake.

I appreciate the extra info regarding the piston fit and ring gap. I was not aware of either.

 

[pa383mopar]

Lifter pumping up after warm. My 383 Newport does the same thing.

Thanks MarPar. The knock I hear is lower-tone than lifter tick and lasts a few minutes. I also hear the lifters ticking right after starting, but that disappears after 10 seconds or so as you would expect.