Head Studs for 7.3 IDI

[BIG DAVE]

where can i find some head stud's for my 7.3 IDI and what head gasket's should i run and should i coat them, and with what

Thanks, Dave

 

[icanfixall]

ARP is the only company that has a stud that will fit our motor. Its actually just around 3/8 inch longer than needed but it works fine. Lots of us are using them. They don't advertise them as a set either. The part number is AR7.000-1lb. The 12 point nuts are ARN 12-1 and the washers are ARW 78 N.. I have used the Felpro gaskets without ever having a leaker. You can use a spray on called Hilomar. Just a little will work fine. Others have used it for years and never had a leaker. I haven't tried it yet but plan to on my next buildup. Follow the torqueing instructions and use the ARP Molly Lube. If you try 30 wt motor oil your torque will need be 30% higher at 130 lbs instead of 100 lbs. Thats a big differance to me in your muscle power. The ARP molly lube is a great friction reducer.

 

[TBigLug]

Can you still pull the heads with the motor in the truck after you install studs?

 

[typ4]

NO

 

[Devilish]

On the topic of these bolt I have some questions.
1. Since these bolts are too long, is multiple washers used to make up the difference?
2. Does the threaded part of the bolt hit the bottom of the block holes?
3. If not, has anyone tried chamfering or countersinking the holes a little to bring the
stud down more?
4. Didn't someone in the past use studs purchased at Caterpillar on their engine?

 

[seawalkersee]

You can throw the heads on, screw in the studs, and then add the washers and nuts though. Extra step, but makes it possible.

SWS

 

[franklin2]

On the topic of these bolt I have some questions.
1. Since these bolts are too long, is multiple washers used to make up the difference?
2. Does the threaded part of the bolt hit the bottom of the block holes?
3. If not, has anyone tried chamfering or countersinking the holes a little to bring the
stud down more?
4. Didn't someone in the past use studs purchased at Caterpillar on their engine?

1. These are studs not bolts, so it doesn't matter that they are a little too long.

 

[icanfixall]

These studs fit. They stick up out of the nuts just a little too far. On my motor the inside of the deep socket bottomed out and rolled the top thread unless I kept the socket perfectly lined up. No you can't use 2 washers. The bottom threads have the chamfer and that will bottom out in the block like its supposed to. Franklin... Yes it does matter if the studs are too long. They are not threaded all the way down the shaft of the stud and the top thread is 1/2x20 and the bottom is 1/2x13. I placed my heads on the block first. Then I installed the studs using a allen socket to speed things up and get them tight in the block. Others installed the studs, then the heads. Its up to you as to how you do this step. About the only way you could remove the heads when studs are installed is to lift the cab up off the frame about 6 inches. Even then it will really be a tuff job and not worth the extra work... If you have a lathe just cut off about 1/4 inch off the top fine threads and they wont be an installation socket issue like I had.

 

[typ4]

Isnt this pretty. They fit like they were made for it. I personally would not coat the gasket because most of them come with a film on them anyway.

 

[RLDSL]

I prefer the Victor Reinz gaskets coated with a few light coats of spray hylomar on each side. Reinz has done more work on modern diesel engine head gasket design and makes all the head gaskets for all those high tech European diesels, including the ones winning all those races, and they coat the things with Hylomar ( a little trick they picked up from us mechanics but only factory ones come pre coated where the engines are being assembled on site.

I would be curious to see if anyone ever got anywhere with having MLS gaskets made for these things by Cometic. That would be the bees knees,( most of the high compression European diesels switched to a MLS gasket at the dealer level a number of years ago, but for some reason it never caught on for these things but you would have to have a near mirror finish on the heads and block decks for those things to seat. The spec is a lot smoother than a lot of shops can provide.

Felpro is consumer grade stuff . I only use their stuff in emergencies and never for head gaskets.

Hylomar is some great stuff especially in temperature extremes, when metal deforms and you get small gaps, the Hylomar stretches and forms a curtain to retain fluids until the engine can warm up and the parts can find their proper shape, then the Hylomar finds it's way back into place. There is a reason that the stuff is the factory sealant on Rolls Royce jet aircraft engines ( the racing version that comes in the spray can is the same as the aerograde version, it just has not had to go through certification so it's a little less expensive)

 

[sassyrel]

These studs fit. They stick up out of the nuts just a little too far. On my motor the inside of the deep socket bottomed out and rolled the top thread unless I kept the socket perfectly lined up. No you can't use 2 washers. The bottom threads have the chamfer and that will bottom out in the block like its supposed to. Franklin... Yes it does matter if the studs are too long. They are not threaded all the way down the shaft of the stud and the top thread is 1/2x20 and the bottom is 1/2x13. I placed my heads on the block first. Then I installed the studs using a allen socket to speed things up and get them tight in the block. Others installed the studs, then the heads. Its up to you as to how you do this step. About the only way you could remove the heads when studs are installed is to lift the cab up off the frame about 6 inches. Even then it will really be a tuff job and not worth the extra work... If you have a lathe just cut off about 1/4 inch off the top fine threads and they wont be an installation socket issue like I had.

studs bottom out????? i was told if you do that--its liable to crack the block at the bottom,,and continue up???

 

[typ4]

They dont bottom out, they go in to the last thread on the stud and the block threads are way recessed to prevent stress risers on the deck.

I used corteco gaskets on my last assembly and they had a white translucent sealer factory applied, may have been hylomar. no problems in 35k hard hot miles.

 

[BIG DAVE]

Thank you guy's one's agen OB come's thow

 

[BIG DAVE]

anyone know a good web. site for them?

 

[Clydesdale]

gary, (icanfixall)what are the dyno #'s on your truck?

What would a thread be w/o a hijack....?