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?

 

Jeff,
Anyone is at risk...But I bet if we did a survey of the trucks it has happend to we would find out that many were running excessive EGT's for long periods or spiked really high egt's on trucks that had somewhat low miles...

IMO..

 

Hot- Cold, Hot-Cold I've been told when your pulling or on the throttle don't just bomb in to it and then let your foot off the gas. Example: Going up a hill, running hot, then cut the throttle and coast down the other side. Instead ease back and slowly bring your egt's down before you crest the hill.

 

Stellite seats have been around for ages. I never heard of one coming out if fitted properly. Craig

 

In-cylinder temps and pressure are higher now than ever. CR indicated EGT is not comparable to the older days of 12 and Vp24 engines.

Thermal control is the key. Mitigate that with:

Airflow improvements ( intakes, camshafts, turbo systems, etc )

Jacket water products like Redline Water Wetter, etc to aid in heat transfer of heat from the iron to the coolant

Water injection systems ( cant say enough here, but remember that lots of meth can rasie the in-cylinder temps while lowering the EGT. Use it sparingly )

Oil ( get the highest flash point you can find if you run high power. Typically the syntheitc stuff will have the highest numbers )

In any one day, the chances of a disaster is small. But it is additive and your chances increase with the number of times.

 

Good Info. I don't get much above 1100* anymore with the twins and cam, so I am sure that helps. I have a set of F1 springs to install here shortly and am wondering if it is worth removing the head to check the seats. I really don't want to take the head off if I don't have to...it is a lot of work removing the twins, etc.

 

what are some symptoms of failed seats?

 

I dropped one about a month ago,didnt fall all the way out,the piston shoved the valve and the seat back into the head crooked,had a wicked miss,did some head damage,after further inspection,four others were spinning,had all the exhaust valve seats made .030 bigger and had bronze seats put in and left the exhaust valve seals off for lubrication and to keep the carbon out of there.

 

Hey K, What did all that work run you and how long didi it take? For a daily driver I would hate to be without for long but it sounds like an inportant upgrade, or atleast something I should do when I fire-ring and stud tha head.

 

me and a buddy tore it all apart,sent the head to local machine shop to have the seats done and the one valve and guide fixed,I put new seals and 80# springs and studs in myself,if i would have pushed the issue,it could have been done ina couple of days,but i have other vehicles so I took my time and did some other work to truck.the upgrade info on the seats came from scheid.

 

I hope I dont offend anybody but after seeing the twins plumbing on the Scheid demo in Effingham ,Il that they were proud of I am curious of the quality of work they do. No doubt they have some awesome trucks but that demo just looks terrible. Looks like they took some heavy wall pipe fittings and hacked'em up with a hammer. Sorry so critical guys but if you weld and work with pipe you would agree that is not the work of a qualified proffesional.

 

I would agree with that,but scheids didnt do any of the work,the only person who touches my truck other than me is dusty at HTS