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Discussion Starter #1
I've been trying to read up on this, I don't have this issue, but I do have a high mileage 6.1 and I'm afraid it's one of those things that just happens. Is it? What can be done to prevent it? What's the main thing that causes it? I know over heating does it, is there anything else I should be proactive and change or maintain?


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have the seats re-inforced.
Usually overheating, but a number of things can cause overheating.

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Are they located on the block or head?


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The seat inserts are in the cylinder head.

The common ones to drop are the intake side.

One of the things - after a hard run, let the engine idle for a time before shutting down.

Much of the time (police department fleets) noted that if the vehicle had been run hard on a pursuit, then shut engine off, if the engine "misfired" on re-start, it was likely a dropped valve seat insert.

(this prevents the valve from closing fully). If the engine is shut off immediately, it may preclude having the valve head to break off or have pieces of the valve break off and cause damage to piston or cylinder walls.
 

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Like hal said, they are in the head and usually intake side.

I'd replace valvetrain components if your doing that too

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Discussion Starter #6
Like hal said, they are in the head and usually intake side.

I'd replace valvetrain components if your doing that too

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Ah I see, which valvetrain components would that be? I'm pretty much lost in the sauce beyond my heads lol I don't know what much of that is.


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Discussion Starter #7
The seat inserts are in the cylinder head.



The common ones to drop are the intake side.



One of the things - after a hard run, let the engine idle for a time before shutting down.



Much of the time (police department fleets) noted that if the vehicle had been run hard on a pursuit, then shut engine off, if the engine "misfired" on re-start, it was likely a dropped valve seat insert.



(this prevents the valve from closing fully). If the engine is shut off immediately, it may preclude having the valve head to break off or have pieces of the valve break off and cause damage to piston or cylinder walls.


That's interesting I didn't know that! Would long drives count as running it hard?


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You don't HAVE TO.. But if youve got the cash and want to take advantage of the downtime and labor (if paying someone to do the job)

Valve terrain includes but not limited to;
valves, lifters, pushrods, rocker arms, springs

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I think my P0305 OBD code (#5 cylinder misfire) recently was due to this as well. No history of any overheating issues either. In my case I had to replace the entire cylinder head! I agree completely with allowing ample time for engine temps to reduce and stabilize after any spirited driving and before turning the engine off. A good practice in general. We do it as a matter of procedure in helicopters.
 

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That's interesting I didn't know that! Would long drives count as running it hard?


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a characterize "hard driving"

runs down the track for 1/4mi or 1/8mi

running high rpm at low vehicle speeds (burnouts, repeated acceleration runs)

and if running high mph runs and shutting engine down during that run, vs. driving at lower speeds and allowing to idle for internal components to cool to more typical operating temperatures
 

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Don't ever allow it to overheat.

I haven't had it happen in a 6.1 but I suspect it happened in the 4.7 in my Ram 1500 truck. Had a crack in the radiator I didn't know about and leaked enough antifreeze to where it couldn't circulate. It was 8F out but the engine overheated very fast. Alarms were going off and the dash was all lit up. Was about to pull over when all of a sudden, antifreeze hit the pump and started circulating again. Cooled down immediately.

I drove it to Walmart and got some distilled water and antifreeze and filled it up. Stopped where I was working that day with no issues. Drove it to get lunch with no issues. Drove it home with no issues. Went to move it from my driveway to the road a couple hours later and it was running super rough. Showed compression issues in two cylinders. Back when this happened, I searched for a long time a I could find nobody else on the internet who had this happen. I finally came across a post from a mechanic who bought one cheap because it was running rough. Popped off the valve covers and an exhaust rocker had fallen off. Popped it back in and all was well.

I took off my valve covers and sure enough, two exhaust rockers had fallen off. Popped them back in and the problem was resolved. I can only suspect that the valve seats had unseated and reseated partially or partially unseated and finally caused the rockers to fall off either when I shut it down when I got home or started it up to move it.

Anyway, that was 9 years ago and it has never happened again. I scoped the cylinders a few years ago and saw no signs of damage to the seats and they were all fully seated.
 

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have the seats re-inforced.
Usually overheating, but a number of things can cause overheating.

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Never heard of having valve seats re-enforced. Also never new this was a fairly common problem, at least on the Dodge motors. Tell me, how do you go about re-enforcing the valve seats. Aren't they typically just pressed in?
 

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Never heard of having valve seats re-enforced. Also never new this was a fairly common problem, at least on the Dodge motors. Tell me, how do you go about re-enforcing the valve seats. Aren't they typically just pressed in?
Yes they are just pressed in you are correct.

Reinforced might have been the wrong word. I kept the eagle heads on the motor, at the time of the build when the heads were off the Builder suggested that i have the valve seats stamped.
From my understanding this gives better retention on the valve seats and will prevent drop in case of an over heat.




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Discussion Starter #17
Don't ever allow it to overheat.

I haven't had it happen in a 6.1 but I suspect it happened in the 4.7 in my Ram 1500 truck. Had a crack in the radiator I didn't know about and leaked enough antifreeze to where it couldn't circulate. It was 8F out but the engine overheated very fast. Alarms were going off and the dash was all lit up. Was about to pull over when all of a sudden, antifreeze hit the pump and started circulating again. Cooled down immediately.

I drove it to Walmart and got some distilled water and antifreeze and filled it up. Stopped where I was working that day with no issues. Drove it to get lunch with no issues. Drove it home with no issues. Went to move it from my driveway to the road a couple hours later and it was running super rough. Showed compression issues in two cylinders. Back when this happened, I searched for a long time a I could find nobody else on the internet who had this happen. I finally came across a post from a mechanic who bought one cheap because it was running rough. Popped off the valve covers and an exhaust rocker had fallen off. Popped it back in and all was well.

I took off my valve covers and sure enough, two exhaust rockers had fallen off. Popped them back in and the problem was resolved. I can only suspect that the valve seats had unseated and reseated partially or partially unseated and finally caused the rockers to fall off either when I shut it down when I got home or started it up to move it.

Anyway, that was 9 years ago and it has never happened again. I scoped the cylinders a few years ago and saw no signs of damage to the seats and they were all fully seated.


When I didn't know better, (19) with my new 6.1 I let it redline when a mechanic shop put the wrong coolant in it to see what MPH the car over heated at. I never did it again but I'm sure that wasn't at all good for my internals. No dropped valve seats though. I guess I got lucky. I think I'm gonna start by replacing my heads soon anyway.


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Because of the two dissimilar metals, the aluminum heats up faster than the iron seat. The rule of thumb on press fit is .006 interference fit. Seats do drop out, but this is an extremely rare situation. some of you said you're going to replace your heads, I don't see anything being gained by this, in fact you might get a head that has less press-fit and they could fall out. Your old heads are proven, if nothing has happened over the thousands of miles you've put on them, Don't worry about it. Drive it hard, have fun!. overheating is the main cause of dropping a seat, simple way to prevent it..... Don't overheat it.
 

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There is a procedure, that I have used on Volkswagen heads in the past. Volkswagen engines being air-cooled the seats Dropout regularly. The way to mitigate this, is to install a new seat, sink the seat about .030, and hammer it with the next size seat driver. This will put kind of a crimp over the top of the seat and we'll keep it from falling out sometimes.......but not always.
 

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frequently, another process that OEMs use it freezing the seat inserts (they shirk down in dimension) and press them into the head. When at ambient temps the seat insert expands and this helps keep it secured in place.
 
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