What is with all the dropped valve seats?

[Jeff_K]

I keep seeing more and more new threads pop up about dropped valve seats. Is this an inevitable problem? or is it mainly seen in trucks that have run high egts. Can they be checked in any way without removing the head? What can be done to eliminate this problem?

 

[JFaughn]

One of the ways I use to look for problems in the valve train is , after removing the valve cover , rotate the eng. by hand , watching the valves go up & down , what your looking for is a differance in length of movment , they should all start at the same highth & go into the head the same depth , if not then its time to look deaper , there can be a lot of reasonds , worn cam lobe , bad lifter , the seat problem , ect.
As for the seats dropping out of the Cummins eng. I can not say .

 

[EXSTROKER]

I think I might have one too :{

 

[LEPage]

I think I might have one too :{

If I had any good reason to think I had one, I'd be finding out for sure. The way I found mine (southbound on I-75 @ 78mph towing & it all came unwound) SUCKS! Photos of damage at: http://pictures.aol.com/ap/myAlbums.do

 

[Udaloy]

Hey LEPage, post your pictures on TDR. Your link doesn't work because I'm not an AOL member, and do not want to be.

 

[LEPage]

Hey LEPage, post your pictures on TDR. Your link doesn't work because I'm not an AOL member, and do not want to be.

It appears that I am to computer stupid to do that. It keeps telling me they are to large... any ideas?

 

[cclark746]

we thank you for the pics and the comments on the pics but i think alot of us are looking for some real answers and real facts on why this happens is it related to running high egts is it related to a certain aftermarket modd are is it just one of those things that happens to people like me and nobody else because you have the worst possible luck known to man.

thanks

 

[RustyJC]

Interference fit valve seats can be something of a black art. If they are assembled with too little interference fit, they can drop out when cold. If they have too much interference fit, they can fail under compressive hoop stress, buckle, and drop out when the engine warms up. If the engine operates such that the valve seat temperatures get too hot, the valve seat will grow and fail under compressive hoop stress just as if it had too much interference fit.



Rusty

 

[Gary - K7GLD]

It appears that I am to computer stupid to do that. It keeps telling me they are to large... any ideas?

This board has pic size/resolution limits - for resizing photos to meet TDR requirements, try an Internet search on "irfan". That will provide pointers to allow you to download a FREE picture editing program loaded with features, including resizing.



Another option some of us use to allow the larger pictures needed for some subjects, or better visual presentation of critical details, is one of the off-site picture hosting sites, such as ImageShack - these are also free, and allow vastly larger and better detailed photos - and then a pointer to that site can be included in posts here and the picture displayed - like this:



#ad

 

[jwilliams3]

LEpage,

Go to www.photobucket.com you can upload them there for free then post the IMG IMG link (that will allow us to see the pictures on this thread).

 

[EXSTROKER]

wen it happens what can it sound like, and power, smoke,noise

 

[LEPage]

When mine went, I really didn't hear much. Thought I heard a tapping noise, which by looking at the piston was contact with the valve that was being held open by the seat that came out. There's no mistaking the extreme amonts of white smoke that was blowing out the exhaust. It built pressure in the crankcase, blew the breather hose off & smoked me out of the cab, also. When I shut it down I had Amsoil running out the exhaust like it was bleeding to death.

 

[LEPage]

Try this link & see if it works for my photos: http://pictures.aol.com/galleries/larryepage520

 

[jwilliams3]

Thanks for posting those pictures.

 

[jglasgow]

Those pictures look exactly like my valve seat and piston.

John

 

[betterthanstock]

When mine went, I really didn't hear much. Thought I heard a tapping noise, which by looking at the piston was contact with the valve that was being held open by the seat that came out. There's no mistaking the extreme amonts of white smoke that was blowing out the exhaust. It built pressure in the crankcase, blew the breather hose off & smoked me out of the cab, also. When I shut it down I had Amsoil running out the exhaust like it was bleeding to death.

You have 6 cracked pistons, but how many dropped seats?



It seems to me you had excessive temperatures, and with the TST you gave it a little too much timing, then added fuel with the EDGE, which makes it look like the EGT is OK, but the actual heat and pressure of combustion is too much. Saved a couple gallons of fuel, but costs you a lot more now.....



I would check the connecting rods for bending or cracks. And if the cracks are caused by knocking, the cylinders and the head may have some cracks too.

Looks like it's cheaper to put in a low mile engine.

 

[TowPro]

anybody have this problem on a stock truck?

 

[Morse]

I've had a very noticeable tick on my 05 for a couple months. . Is this something I should be concerned with much?