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That certainly explains why the valve margins are clean in your post 23.
The valves have been kissing themselves.
Are all the valves like this, are they all the same, some worse than others, or some not worn at all?
I would find it hard to believe they are all like this. How on earth the engine ran at all without snapping valves off.
What valve stem seal was fitted?
Looks like it had a bad combination of valve guide material, and NO lubrication past a positive valve stem seal, which viton is very good at.
Ultimately the valve stem seals would have let oil through, the engine would have been a heavy smoker, since the seal would have pulled out of round while the engine was running.
It would come down to the cylinder head manufacturer's choice of guide material as the cause.
That certainly explains why the valve margins are clean in your post 23.
The valves have been kissing themselves.
Are all the valves like this, are they all the same, some worse than others, or some not worn at all?
I would find it hard to believe they are all like this. How on earth the engine ran at all without snapping valves off.
What valve stem seal was fitted?
Looks like it had a bad combination of valve guide material, and NO lubrication past a positive valve stem seal, which viton is very good at.
Ultimately the valve stem seals would have let oil through, the engine would have been a heavy smoker, since the seal would have pulled out of round while the engine was running.
It would come down to the cylinder head manufacturer's choice of guide material as the cause.
Gary
Hello Gary.
All valves are not like N°7 exhaust I show you in the video. 2 or 3 others are like that. All others have minimal wears but out of normal wear.
Every intake valves are full of burn oil and some exhaust too (but not all).
Viton valve stem seals were installed and when you look at them upper lips are damaged.
You're right.... my engine was smoking a bit before disassembled it but what I most found was excessive oil consumption.
Well what I'm going to do is to replace valve guides (#9704 Edelbrock ref - for FE heads), do a seat job. My machine shop is going to check valves and if they are ok he will do a valve job.
I am sure the Edelbrock family would like to know about this.
I don't see this as an assembly problem.
Considering not one other member here including one FE expert (Brent Lykins) has seen this happen with this type of guide, points to a metallurgy issue, when your guide batch was made.
Or perhaps number of cold starts versus run-time at operating temp.
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
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Quote:
Originally Posted by Gaz64
Considering not one other member here including one FE expert (Brent Lykins) has seen this happen with this type of guide, points to a metallurgy issue, when your guide batch was made.
Or perhaps number of cold starts versus run-time at operating temp.
Oliver, is there a stamping on the outside of the valve guide that is visible? For instance, the Edelbrock guides (which it is said you do not have) often have the number 39-1119 on the outside. Of course the inside diameter of that particular Edelbrock guide is already too big for an 11/32" valve. But it would be interesting to know if your guides have an identifying stamp.
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