Threaded Rod vs. Head and/or Manifold Studs
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=132836
Printed Date: 17 Jun 2025 at 5:36pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Threaded Rod vs. Head and/or Manifold Studs
Posted By: MN-Realtor-Farmer
Subject: Threaded Rod vs. Head and/or Manifold Studs
Date Posted: 19 Dec 2016 at 10:51pm
|
Currently working on putting back together my WD, and I noticed that the air intake and exhaust manifold studs are pretty well worn. At my next chance I headed over to my favorite parts supplier's website and found that they were $5 each. That got me thinking. Why can't I use threaded rod cut to length with the appropriate nuts to achieve the same results? Has anyone tried this? What am I not considering here? Theoretically could the same thing be done with the water manifold and the head rods? |
Replies:
Posted By: CrestonM
Date Posted: 19 Dec 2016 at 11:45pm
| I'm thinking head bolts need to be a certain type/strength. "Other" types may stretch easier. |
Posted By: shameless (ne)
Date Posted: 20 Dec 2016 at 12:08am
| I think you'll just strip out that threaded rod. |
Posted By: DougS
Date Posted: 20 Dec 2016 at 5:12am
| If you go with the wrong material you can consider those studs to be seized in the head forever. |
Posted By: Butch(OH)
Date Posted: 20 Dec 2016 at 5:34am
| Go to your neighborhood auto parts place such as Advance,Auto zone etc and look in the Help Parts section for the exhaust manifold hardware kit. You may need a couple kits to have enough of the right ones but included is nice brass nuts, washeers and good quality studs. It will also be cheaper than $5 each |
Posted By: jaybmiller
Date Posted: 20 Dec 2016 at 5:55am
|
When I installed a new manfold gasket on 'Paris', I 'cheated' and used cut down, rethreaded bolts and regular nuts(2 washers though). I know I ain't going to live long enough to complain 'I should have used the correct parts'. Using 'proper' parts would cost about 50 Canucks...I have free bolts and lots of time. Jay ------------- 3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor) Never burn your bridges, unless you can walk on water |
Posted By: LeonR2013
Date Posted: 20 Dec 2016 at 5:56am
| I don't know what they're costing now but you can buy grade 8 all thread rods. They come in 36" lengths and various sizes. I have in the past had problems with brass nuts on exhaust studs so went to stainless. It may have been my fault by over tightening them, but I have had problems with the brass nuts seizing and ruining the stud. I don't why a exhaust pipe stud won't work if you get the right size, and we know they're tough. |
Posted By: bradley6874
Date Posted: 20 Dec 2016 at 6:05am
|
Manifold bolt usually screw in to the block UpTo the end of the threads that shoulder where the treads stop is what seals the ones that screw in to the water jacket all tread WILL leak ------------- You can wash the dirt off the body but you can’t wash the farmer out of the heart and soul |
Posted By: MACK
Date Posted: 20 Dec 2016 at 6:23am
| Stainless steel nuts will seize to bolts then a torch will not cut them off. Best to use a good grade 5 nut. MACK |
Posted By: Allis dave
Date Posted: 20 Dec 2016 at 7:34am
|
Couple things here. Studs like that are usually grade 8 or even 9 which is much stronger. Stud and bolts are also stronger that threaded rod. Say you have a 1/2 bolt, most of the bolt or stud is 1/2 diameter, but when you have threaded rod the threads take away some of the meat. SO now lets say that it's only 7/16 diameter. Grandpa had an old wagon that had the tongue attached using a rod that was threaded on each end. The rod broke one day. He replaced it with threaded rod and he broke it again about once a month, 3 times or so until someone told him to get a solid rod, threaded on both ends. It never broke again. 2nd thing is removing the old studs. You have a fairly good chance of breaking one when trying to remove it. Then you're down to trying to drill it out and hope you don't ruin the hole. If you're going to remove them yourself, make sure to get a stud extractor for the best chance. The machine shop removed mine for about $30 and I bought a new set from DJ's tractors for about $30. Be careful with Steiners. They have good stuff, but can kill you with shipping. Lot's of good sellers on this site. |
Posted By: PaulB
Date Posted: 20 Dec 2016 at 9:34am
|
Even at $5 each that will be cheap compared to the problems you'll have after using all-thread
rod for manifold studs, even worse for head studs. Penny wise and dollar foolish, I'd say. The plating on all-thread is not compatible with the heat that a manifold will encounter, and they are also grade 2 material. Head studs will be grade 5 in older engines at least. ------------- If it was fun to pull in LOW gear, I could have a John Deere. Real pullers don't have speed limits. If you can't make it GO... make it SHINY |
Posted By: Steve in NJ
Date Posted: 20 Dec 2016 at 9:42am
|
Threaded rod is definitely not for high vibration, heat, and clamping force. Use a regular grade 8 stud to do the job. You'll have nothing but nightmares using threaded rod.
------------- 39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife |
Posted By: HudCo
Date Posted: 20 Dec 2016 at 10:26am
| my wd got an new manifold and could not get studs from the local parts houses because they were out and couldnt wait a day so i got grade 8 bolts long enought to cut off the heads and threaded to be just like the studs that were being replaced new copper nuts and gaskets and all is well |
Posted By: 79fordblake
Date Posted: 20 Dec 2016 at 12:22pm
| I would just spend the 30 bucks and get the right studs and brass nuts. Unless I absolutely had to for some reason I wouldn't use threaded rod. |
Posted By: steve(ill)
Date Posted: 20 Dec 2016 at 12:34pm
|
Paul is right....... most studs on trucks/ tractors are grade 5.. Head bolts are better... allthread is galvanized grade 2 , cheapest crap you can buy ........ they do make grade 5 threaded rod, but premade studs cant be that much more expensive. ------------- Like them all, but love the "B"s. |
Posted By: Bill_MN
Date Posted: 20 Dec 2016 at 4:09pm
|
Talk to one of the vendors on this website, e.g. Tony's Tractors, OK Tractor, DJS Tractor Parts- most sell a manifold stud kit for the WDs, already the right length/size and they come with brass nuts to prevent seizing. Reasonable price for having all the right hardware in one package and good to support these guys.
------------- 1951 WD #78283, 1918 Case 28x50 Thresher #76738, Case Centennial B 2x16 Plow |
Posted By: LeonR2013
Date Posted: 20 Dec 2016 at 5:52pm
| Well, I guess I didn't make myself entirely clear. Obviously many have had success with the fasteners that they prefer, and obviously I also had success in some of the misfit ways I did things. If you go to the people that specialize in fasteners you can get 8 grade all thread but I don't think you'll save any money. I don't remember what the last ones cost that I used on a gas delivery truck but it was a pretty a healthy price and they did the trick. If you try to thread a 8 grade bolt you can do it, but it will take an awfully good threader or you won't get a good clean job. But you've got the right idea. Do anything you can do to save a buck just for the fun of it. Just use a good product like you will get from the venders on this site. |
Posted By: HudCo
Date Posted: 20 Dec 2016 at 7:49pm
| the studs were meant to bottom in the head to create a good seal in the water jacket |
Posted By: Rltool
Date Posted: 21 Dec 2016 at 6:14am
|
I do like HudCo did with grade 8 bolts. I have a bunch made up. I've tried to find the studs at automotive suppliers. But haven't found them any where the same as or close enough to originals. The cost for a single set isn't to bad considering what you get. The problem is when you multiply it by the number of tractors you need them for. With the heat expansion lower grade mtl studs will stretch. Thru my work I can buy bolts & brass nuts in bulk. Being a machinist & having all the right equipment readily available kinda helps too. I make them with a little more thread to go into the head for better holding. Ray W. |
Posted By: LeonR2013
Date Posted: 21 Dec 2016 at 6:41am
| There's something here I sure don't understand here. I agree 100% with using grade 8 bolts even when I knew the bolt didn't need to be that good. But I don't get the point of using a brass nut if you think you need the clamping force of a grade eight bolt. That being said it was probably my fault that I over tightened the brass nut and ruined it. That's why I preferred the stainless that didn't rust to the stud very bad. They did have a tendency to back off without some kind of lock. But my way is certainly not the only way, and I respect other opinions and ideas. This is a great place to come to get problems solved. |
Posted By: Michael V (NM)
Date Posted: 21 Dec 2016 at 8:32am
| I really wouldn't want to use a grade 8 bolt for the manifolds, because with the heating and cooling, they will still weaken,,,now if ya hafta drill em out,,, ya gots a grade 8 to drill. brass nuts are really easy to cut off or heat em a little any will usually turn loose,,, and also the manifold nuts/bolts only take like 20-30# torque.... |
Posted By: Dakota Dave
Date Posted: 21 Dec 2016 at 8:36am
| If your stripping the brass nut trying to get enough clamping force you've got bigger problems. either your manifold isn't flat or the head requires decking. The brass nuts are sacrificial they are suposed to strip out when there to crowded to get off any other way. The studs can then be cleaned up and resumed. Except usually the engine gets run so long leaking it runes the studs and erodes the head. Then it needs to be removed and decked to get a manifold to seal. |
Posted By: Gary Burnett
Date Posted: 21 Dec 2016 at 8:52am
|
Use the right studs and brass nuts. |
Posted By: desertjoe
Date Posted: 21 Dec 2016 at 9:15am
|
I also do like HudCo,,,,,  |
Posted By: Gerald J.
Date Posted: 21 Dec 2016 at 9:18am
|
Brass nuts can be as strong as steel, but have to be tall nuts. Standard height nuts will be weaker in brass, especially jam nuts that are very short. Just a sturdy brass nut needs more threads in contact with the stud than a steel nut. Gerald J. |
Posted By: JimD
Date Posted: 21 Dec 2016 at 11:24am
|
Our's are on sale right now: http://oktractor.com/zen/index.php?main_page=product_info&cPath=1_15_207&products_id=348" rel="nofollow - http://oktractor.com/zen/index.php?main_page=product_info&cPath=1_15_207&products_id=348 ------------- Owner of http://www.OKtractor.com" rel="nofollow - OKtractor.com PM for an instant response on parts. Open M-F 9-6 Central. We have new and used parts. 877-378-6543 |
Posted By: jange01
Date Posted: 21 Dec 2016 at 11:34am
|
IIRC the correct / original manifold studs are slightly oversize. That is the threads are cut with an adjustable die and made slightly larger for the portion that screws into the head. I believe this is to help aid in sealing off where the studs go into the water jacket. In any case, also use a sealer on the threads into the head. Jim
|
Posted By: LeonR2013
Date Posted: 21 Dec 2016 at 1:23pm
| That should take care of that. And didn't have a falling out over it. Good show. |