I was under the impression that the Dodge nuts were locking as well. Every other turbocharged vehicle I've owned or serviced has had locking nuts on the turbo, and yes, I've dealt with a number of gasket blow outs due to nuts backing off (never on a CTD thankfully).

 

yes i dont know what a crimp style lock nut is.
The vehicle is a 1990 thomas school bus. It did not come with lock washers on it i was adding them myself because i have a bunch of them at home already.

 

it is on a bus, but i meant i have some lock washers at the house, i am gonna add those under the nutz to make sure they dont vibrate loose and wreck my replacement gasket, I will find out as soon as i finish polishing/painting my valve covers, bolt back up my exhaust and weld on a bracket, and buy a battery for the beast.

 

I'm talking about the kind of nut that they crimp one end to make make the bolt have to push through, creating a very strong bond between in the process.

 

oh weird. yes i am going to use split ring lock washers under the nuts so that there is constant pressure to avoid them becoming loose and rotating off due to the vibration.

thanks for posting the pic though

 

well i wrangled a gasket from the local "Diesel parts of Carolina" and here it is.
my question is, and this may be dumb, but which side does the ribbed side face?
raised portion facing turbo impellor? or raised portion facing down into exhaust manifold?

as a reward for you helping i submit these photos of my polished valve cover tops with gold sides, VHT metallic engine enamel with duplicolor high temp clear over it.
followed a thread on diesel bombers, went with a satin rather than mirror finish because I am a busy guy and mirror takes twice as long as "shiny"

 

That "rib" is designed to crush to make a seal. That being said, it doesn't much matter which way it's turned, as it will be crushed either way.

 

I would use prevailing torque lock nuts rather than lock washers.
Some of the Jap engines use a very strong spring under the nut to keep the manifold tight.

 

That is essentially what the lock washer does. It pushes out to keep tension on the nut, which will be tourqed and lock tighted down.
I am doing it. And I it loosens up I will be sure to update this thread.
Thanks for the suggestion I just already have all the tasteless I need to wrap this up.

 

the lock washer WILL lose its tension under heat

 

What also happens with the expansion and contraction of the manifold the torque gets too high and bulges the lock washer out.
It basically becomes a flat washer.

 

well you guys have seriously bummed me out. The fact is that the new gasket has been installed and it is all tourqued down and everything.
seeing as how it is now crushed in there i am going to run it with the locktight and the m12 lock washers and see what happens. This is a recriational vehicle and not a DD.
next time i take a long trip i will pick up a new gasket and some of those crazy nuts to have on hand in case it does back out. but i am not going to undo my setup because it may fatige and fail in 10,000 miles because i would need to use a new gasket to be sure of a good seal. also because i have only driven the bus maybe 7 or 8K in the 2 years i have had it

Anyone know offhand where to get those nuts or what size/pitch they are?

 

This is getting entirely too complicated. Run what you have, check the torque periodically. You can loosen the flange, the gasket will reseal. I've done several turbo swaps, all with the factory flange nuts, and none have come loose. I wouldn't be in a rush to go change out something that hasn't failed yet, and has a very good chance of not failing.

 

There we go, thanks for some suggestion based on experience, I am gonna run the original nuts with the lock washers and report back how it goes after my next long haul.

 

so just to update the bolts and nutz i used seem to be holding fine on keeping everything together and the new gasket seaed the turbo up well.

I can here it whirring back there but maybe that is just because i deleted to old rusty muffler and now it is nothing but 4" straight out to the pavement. ?? not sure. ill double check those nuts next time i am back there but to date it has been fine and i have driven it on a few highway trips, short but def. full temp full speed.