Well finally ordered a set of arp head studs so I can change my turbo again and add some more boost. I ordered them and a set of haisley machine 60 lb springs from a buddy of mine who owns a small diesel shop. I asked him about milling the rockers and he said he's never installed studs with milled rockers and that he has a different method. I was curious as well but he said people would probably die if they found out how to do it so ill find out the secret when I go to pick up the parts.

I plan on installing these studs one at a time without pulling the head but he said the rockers would be loose or removed so it'd be a good time to do springs also. Has anyone done it like this or have any tips? I looked through the sticky on the 60 lb valve spring install and will probably follow that and hopefully not drop a valve in the cylinder

But I also read in there that its a good time to change the valve stem seals? I've heard a little about these but never really seen them or know what they're like or how to change them? Would it be a good idea to change them or how big of a pain are they to change? Also where do I get new ones or what's the cummins part #?

Any tips or advice is appreciated. Thanks

 

Keep in mind there are two kinds of valve stem seals for the 12 valve heads. I can't recall exactly what the difference is but last summer I got the wrong ones, kept my truck down for an extra day.

 

I've been through this the cummins upper end kit comes with the wrong ones. Jimbo will chime in here, He has the correct part number.

 

These are the seals you DON'T want. Cummins should have them but I got these with the upper engine gasket kit and they didn't fit around the valve guide boss. I informed the parts guy at Cummins that they didn't fit and he refunded me the cost but never said they had others. The engine builder I had my head machined at had seals that worked. I guess they're pretty generic.



Cummins P/N: 3921640. Don't forget you need 12!

 

92 Smokinblacky I think since you are doing all this you would be better to go ahead and pull the head and do the head gasket. I'm afraid you will be sorry if you dont.

 

Well the point is trying to get my stock head gasket to last. I've heard of guys studding them one at a time and holding 60 lbs numerous times with no issues. Im gonna do this and run it til the head gasket goes then ill have the head ported and fire ringed. If im gonna pull the head I want to do all that instead of just change the gasket. But right now I don't have the funds nor the time. I gotta have this truck up and runnin ready to go for saturday as I will be pulling at another truck pull, this time with my bigger turbo in the 2.8 class. Sad thing is this stuff probably wont come til wednesday so im already gonna be in a rush.

As far as the valve stem seals, I talked to my buddy again that owns the shop and asked him about them. He said if im not having any oil burning problems (which im not) then not to worry about it. He said he's changed at least 15 sets of springs without changing them and having no problems with them at all. He said that he knows a few guys that changed them and then had more issues. If it ain't broke, don't fix it he said ha ha.

Im still debating on this, with 253k I was thinkin it would be a good idea but after what he said I don't wanna have more issues. It would save me a little time and money right now since im already in a bind and I guess if I did have problems with them after installing springs, I could change em. later.

But I was curious to know what the rough price for 12 new valve stem seals would be and how hard they are to change? Probably easier with the head pulled right? Debatin on if its worth doing now or later when I have issues with them or have the head pulled...

 

I just got my studs yesterday too. I'm not as brave as you though. I'm going to do studs, springs, headgasket o-ringed head, maybe a cam too. I'm also going to switch to the S357 that I have temporarily so I can sell the S362.

 

Those valve seals cost me about 35 bucks from a local auto parts store IIRC. Pretty easy to change too...

 

I have never done them on a diesel, but, it seems to me that you are already doing all the stuff necessary to remove the springs, why not slide on new seals while you're in there? Just my opinion and philosophy of fixing my cars...Mark

 

I would change the headgasket. Reason being it has 253k and is 19 years old. If you knew it had been retorqued every so often then I wouldn't worry about it.

You also say you are adding a bigger turbo.


Idk if this is the wrong thinking but I thought with studs they were locktite in??? If so, when the gasket blows, you would have a harder time changing it as the head needs to be pulled over the studs.

 

The way I look at it is the head is still sealed good now, so why ruin that? Rather im just gonna improve on the clamping force for as long as the head gasket lasts. I know many guys that have done it this way, some with more miles than my truck and gotten good results. I should be seeing only about 50ish lbs of boost with this big turbo as a single and im thinking it should handle it. Talking to my friend again he said studs are simple to pull back out and he said he'd do what I am gonna do. Im gonna try it and see how long it lasts. Gonna test my luck.

 

To install head studs the right way, the cylinder head should be removed and the holes in the block be bottom tapped.