Read this before you swap...

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pishta

pishta

I know I'm right....
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Ok, what is up with new hemi valve seats falling out of the heads???? My buddy has a 300C 5.7 hemi. Has about 65K on it and it dropped a valve seat about 2 months ago. Drove it, stopped for gas got back in and started it, motor made an awful noise and power was way down. Took it into the dealership and they mechanic knew what happened even before the story was over. And the kicker: The warranty doesn't cover it because it is an "unlubricated part". What the H? So $1600 later (and a 90 day warranty on the new head) he is back on the road with a car that he doesnt really trust anymore as the mechanic told him "it can happen at any time". So, he calls me a few minutes ago after driving about 20 miles..it happened again! He is hoping its the warranty head or else he is out another $1600 and will unload the car after its fixed. He loves the car, but hates the valve seats! Its all over the place on the internet, but the consumer reports says its a good car. look here http://dodgeforum.com/forum/3rd-gen-ram-tech/197085-hemi-valve-problem.html and other places...Why would they just fall out, could you do something to the new heads seats before you install them?
 
"UN-OILED PART?????????" ("unlubricated part")

Time to add oil squirter's!!!!!
 
blah blah blah this has come up before. I call bs I need pictures. I've yet to see actual proof and have 3 hemis apart in my garage 2 high mileage(1 busted rod one spun bearings) 1 was 10000 kms on it and have yet to see any evidence of valve seats going anywhere.
 
The only time I saw seats fail was when the engine was over heated and cause the heads to expand.
 
First time I have heard about it. First question would be why wouldnt they replace both heads? Not much more work since you are already there. Sorry for his misfortune.
 
the exact thing happened with chrysler when they were making there own hemi gen II hemi heads... seats were FALLING out of them... greg has two motors to prove it...

this was before they signed to have Eddy make there heads... and for the money they charge just get the stage V's...
 
That's exactly what happened to the engine I bought before I got it. They thought that a ring land chipped, but after looking it over closer when I bought it I noticed half of the valve seat was missing. The main issue is just that they are aluminum heads with hardened steel (or whatever material) seats, so thermal expansion can be a issue. Like was mentioned earlier, I think it only really tends to happen when they get too hot. My engine was supposedly out of a police car, so I can buy that. I'll see if I have a decent picture. I know I have one of the beat up head, but not specifically of the valve seat.

And even though the issue may be all over the net, it's probably more than likely because it's on the only issues these engine tend to have. However, there are over a million Hemis already on the road, so what percentage does it really affect is the question. Hardly anyone ever gets online to praise stuff, they only post when things go bad, so if you look up issues for any particular car/engine you'll really only ever see the worst things people have to say. They also say Hemis like to spit rods out the block, but if you look that up almost every instance involves sucking in water (rainy day, big puddle, etc.).
 
i have personally seen a case where the valve seats have fallen out into the combustion chamber. last year one came in "5.7 hemi". 2 cyl on one side and 1 on the other. i have heard others talk about it also.
 
Just out of curiousity I did a google search. Looks like this happens, not allot, but it happens.

Sounds like it causes the valve to hang open and hit the piston (among other bad things).

This is one thread, more threads about this are out there.

http://speedtalk.com/forum/viewtopic.php?f=1&t=15456
 

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Haha, yep, that's pretty much exactly what mine looked like on the inside. Those little pieces of metal beat up the piston and head pretty bad.
 
Yes i have seen this be4. A lot of 4.7 have this problem, The 4.7 and the 5.7 come from the same company.So i asked a local machine shop. He told me that they take a hole punch and a hammer and go around the outside of the seat. He tells me that it helps make psi around the seat. Don't know if it really works but he hasn't had one back yet...
 
4.7 and 5.7 having a problem, my Jasper rep said they are putting new seats in and fitting them tighter. Also metal fragments get into the intakes, You have to replace or clean for warranty on these engines
 
4dr4ever said:
blah blah blah this has come up before. I call bs I need pictures. I've yet to see actual proof and have 3 hemis apart in my garage 2 high mileage(1 busted rod one spun bearings) 1 was 10000 kms on it and have yet to see any evidence of valve seats going anywhere.
Click to expand...

Uhh, still calling "BS" on this? C'mon.....need more pics? Ill get a few from him. I like the idea of peening the edges, that is what I suggested to him, but didnt know it was a "working" practice.
 
You do realize how many Hemi there are running around correct? I Personally know of 15 of them that are in the 9 sec range and have never had and issue, I have owned my Charger with a 5.7 for 6 yrs and have never had and issue. I have owned a stroker and never had an issue, now I own a forged supercharged 6.1 and still don;t have any issues..Not sure why you would start an alert post like this?
 
pishta said:
I like the idea of peening the edges, that is what I suggested to him, but didnt know it was a "working" practice.
Click to expand...

I don't like the idea of peening the edges. The stress and pressure from peening the valve seats may also make the seats "out of round". I ran the head lines in an engine plant and know the tolerances. The roundness for the valve seats is held to 13 microns ( or 0.013 mm). This is a VERY TIGHT tolerance to hold and we had the machine operators for the valve seats check them every 10 - 15 minutes. 1 mm is equal to .040", so take .040" and cut it into 1000 equal pieces and then take 30 of those. It is thinner than the diameter of your hair. Peening them could throw them out of roundness unless you remachine the seats afterwards.

The only reason that the seats would fall out is if they did not get their press fit correct which is determined by the hole size. The hole size tolerance is so tight, you cannot just use a drill and keep it in spec., you have to use a reamer which can hold a tighter tolerance. This is also monitored in the machining line with load cells to monitor the press in load for the seats. They set the limits of the load cells by testing sample parts to determine the acceptable load for a good part. If it allows a bad (not enough press fit/interference) part through, they did not properly establish their limits, or someone opened up the limits on the press in operation for the load cells.

I was involved in a change to the metal that the seats were made of and had to test the new parts to make sure that the limits were acceptable for the new parts vs the old ones. There was a difference in changing the hardness for the seats and we had to establish new load limits.

Bottom line, if they had proper control of their process like they are supposed to, this wouldn't happen. It is the responsibility of the head machining plant, which in this case is in Mexico for the 5.7 L engine, to keep their process under control.

The engine plant that I worked in literally made 1 million heads per year and we never had a problem with the seats falling out.
 
I am not worried. I drive a 04 Ram with a 5.7 every day and have had no issues and my car is getting an 03 5.7.

The guy with the 300C....did he check his cooling system...20 miles would be just enough to overheat the thing again. Most of the issues involving valve seats on aluminum heads has to do with overheating the head. And this is not a new issue. If you overheat an LA engine you crack the head...same on most cast iron engines. Operator error or poor maintenance practices will kill an engine faster than anything. Sometimes you don't know you have an issue until its too late, unfortunately it happens but the majority of these engines are out there still kicking.

My vote as a driver/operator/owner is go late model 5.7/6.1 all day long and put the old stuff for sale for the resto guys!
 
Always the intakes seats. There's a message here. Intake seats need more press fit than exhaust. Why ? Intake seat is weaker, runs much cooler than exhaust seat and therefore won't grow as much when aluminum head does. Best fix is aftermarket seats, that are stronger/higher alloy, with a greater thermal growth, to keep the press fit, when up to operating temp. Local shop gets $8 each for labor to R & R., $'s well spent. This makes a good time to upgrade your 5.7 intakes to 6.1's. Much better/lighter,(hollow) valve and better flow. New ebay take-outs are dirt cheap. Good Luck, ateam.
 
Is this issue related at all to the infamous "Hemi Tick"?
 
Nope, thats pushrod length.
 
That tick can sometimes be attributed to cracked exhaust studs as well, though it will probably be noticeably louder. The earlier studs had an issue with this, and my 06 one even did. One if not two studs broke off right at the head. I got lucky though, that was the first time my screw extractors actually worked like they were supposed to, lol.
 
USCG CHARGER said:
.....Not sure why you would start an alert post like this?
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Because he (who was a professional auto mechanic and is currently an aerospace worker..user error not likely) dropped 2 in a matter of 2 months, just sayin'.....kinda like "look for cracks in '302' heads". Its just an FYI. The more we know, the better. I would play the averages also, 100 in a million sounds good odds to me too. How about this: IF you do the swap and have the heads off, spend 8 bucks a hole and get new intake seats put in for peace of mind, how's that?
 
4dr4ever said:
blah blah blah this has come up before. I call bs I need pictures. I've yet to see actual proof and have 3 hemis apart in my garage 2 high mileage(1 busted rod one spun bearings) 1 was 10000 kms on it and have yet to see any evidence of valve seats going anywhere.
Click to expand...

A friend of mine experienced this very thing, he took it to the dealer, under warranty, and they fixed it.

With only 27000 on the clock.
 
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