First let me say these rods look great!
The instructions inclosed must be missing some information.
They state T rods include new nuts and bolts, these use the "*one use" 12 point cap screws. *per Snyder's catalog
The instructions show 45FP torque with .001 to .002 clearance. My beam type torque wrench was showing over 75 FP before the bolt started to turn right out of the box. Wouldn't that use up the "one use" right there?
I may be the only one that has not had to deal with a 12 point (or not) in the past so it was a trip to the machinist to get help as the only socket that fit was a 3/8 12 point but it was loose.
(That's what he told me to use so maybe adding a note would be good)
Do I treat these like insert type bearings and just set the clearance or do I treat them like babbitt bearings and fit them to the crank? (crank turned for .020 under) The first rod I did as normal for babbitt rod but the more I got thinking about it wondered if I was doing it right. The 2ed rod I just fit right out of box and got .0015 with full shims. That is where I stopped to ask this.
What is the correct torque? If these are to be torqued to 45(?) what can I torque them to safely for set up so as not to have to replace the bolts?
Maybe a note for people that have never done new or rebabbitted rods that the flash between the two half's needs to be cleaned up before use.
All the engines I have done so far have been rebabbitted old rods with nuts and bolts so this is new water for me and maybe other future customers buying these rods.
Just curious, do the bolt heads have ARP stamped in them? If by chance they do, they are NOT one time use bolts.
Why in the world would they put a single use bolt on a T rod knowing full well you have to reset them some times? Order bolts everytime you need to set rods?
Seems a bit strange.
I understand when we rebuild a 100 year old engine the old rod bolts have really been thru alot and replacement is not a bad idea, but with 1 use bolts?
I have these rods. Love them... I needed .017" so i bought 0.020" and had them pin bored to size. The bolts were hellofa tight to loosen.... But I put them on with the shims that came with them and because of the one use thing... A dab of loctite.
So far so good. I tightened them about as tight as they were when I got them FYI.
Hope this helps
I thought it was the nuts which are "one use."
p.s. -- You can use ordinary nuts to do all the fitting, then use the lock nuts for final assembly.
They throw the bolts and nuts away when they re - babbit the rods. You keep using them until next rebuild. So the bolts and nuts are "one use".
I threw the nuts away and used an aircraft castellated nut (torqued to 35 lb - ft if you insist on using a torque wrench).
45 lb - ft is a LOT for those tiny bolts.
You set clearance by removing shims until the rod cannot be moved fore and aft on the crank with a tap from a light hammer. After each rod is installed you need to check that the engine still can be turned using the hand crank. If not, it is too tight.
Clamp the big end of the rod in a vise when loosening the nuts from the uninstalled rods or you will ruin the rods.
How about some photos?
Are the rods being discussed newly made?
Can they take Babbitt?
Do they have a floating piston pin?
Ron the Coilman
These are the rods and bolts I am talking about:
12 point cap screw
I will look for the APR number.
What often happens at Snyders is a product being offered that solves a non existent problem. I had no idea there was such a thing as a new Model T connecting rod. I've heard of original connecting rods failing, but those failures were a result of bad mechanics doing dumb things.
Original Model T con rods are ridiculously reliable if rebabbited properly after magnuflux inspection and straightening. I suspect the originals will prove to be more reliable than these new ones. Very scary stuff here. I bet they are forged in China, which does not guarantee failure, but it scares the crap out of me.
Royce you brought up the 1 thing I forgot about. The castle nut.With a cotter pin that is better to me than a lock nut of any kind.A lock nut could give you a false impression of torque I guess would be the word to use.
And a question that may amount to thread drift.
Why not make a aluminum rod similar to what is in a Briggs or Kohler engine? Turn the crank to a exact size, and order the rods for that size already cut to fit with correct oil clearance and put in and go?
Part of the picture is availability and cost of core light rods. The cores I have for this job are the heavy rods. The guys I checked with wanted $25 each for the light rods, add in shipping to send the rods in plus time to run around getting the rods these seemed a better deal plus they have built in oil dippers.
There is no lock nut, it's a 12 point cap screw with the threads being smaller then the shank. I don't see any numbers on them. That's another piece of information that is lacking, what are the bolts, what is a part number so I can get them local and not have to order them. I think the new Model A are made the same way.
They look like a Chinese copy of an ARP or SPS rod bolt for small block Chevy. They use an interference fit nut and the stretch of the bolt needs to be measured with a stretch gage. A torque spec is not appropriate.
I have friends who use Eagle and SCAT Chinese rods in their FE Ford engines. They toss the bolts and get good ones from ARP. I use ARP bolts in original Ford rods in my Ford FE engines.
Here are the real ones:
I have found that it is becoming much more difficult to find GOOD caps. So many of them have had too much filed off of them. So then you need to set them up in a milling machine to true them up as usually they have been filed crocked. Now if you try to use them with a standard size crank you need to use a double shim pack to keep from boring the babbitt through back into the steel. It is reaching the stage where I am thinking of making just some caps for my own use. I have also thought about getting some rods investment cast from 4140. Not forged I realize, but at least I will know that they are made from good material and made at a quality foundry. And it is not like the T engine is exactly highly stressed.
I do like the idea of using cap screws instead of bolts and nuts
I haven't checked Mac's but Lang's only carries the NEW rods for insert type bearings. The rods Lang's show in the catalog look the same with the same description for the cap screw.
Well this is another fine mess I have gotten myself into! IN the end it will all work out but for now there are a couple of hurdles to get over.
Don't the new insert bearing rods require pressure oiling? I thought I saw that note in Lang's writeup for the rods.
Yes, for the insert bearing rods, that's how I read it too.
At this point I can't start over, unless there is a recall on this item. I will order a new set of bolts, use the ones that came with the rods for setup then install the new ones for final assembly. I will then anticipate ordering a new set for later adjustments. Or just use low strength thread lock.
I guess I don't understand why you would send a product out with pre-stretched bolts and no information to go on. If the bolts are installed as tight when shipped in the insert type rods, when you go to install them you would need a 2ed set of bolts to do the job also.
Mark take more pictures of the babbitt in the rods, and also of the flanges on the outside of the cap and rod where the babbitt meets the steel.
Will do. I think I know what your thinking. Could it be drill out the threads in the rod and machine a flat for a bolt? I was just looking at them wondering if that would be the way they should be.
The diameter of the hole the machined area the bolt fits into is about .3935 / 10 MM. The machined area of the bolt is approx 9.97 MM. The height of the area the bolts head sit on to center line of rod is;
T .979 new rod .968. A 3/8 fine thread goes into the threads but is lose. Looking at the new rod I don't think there is much you could machine away to give you a flat with (for lack of better word) wall to prevent the bolt from turning locking it in place.
These photos are a little on the dark side even with flash;
Interesting that they use metric bolts. That explains the problem you had with the fit of the socket. So a metric socket should fit correctly. It certainly explains the 45 ft lbs torque.
Why would you want to machine a stress riser notch in your nice new rods. I know here metric bolts are readily available at any good bolt/industrial supply house.
Mark, did you know that the rods have lead Babbitt in them?
Take in account that I have used Timesaver on that rod to fit it to the crank. When you scrape it it is shiny like other rods with tin based babbitt I have seen. But I will look closer.
That was just a passing idea.
It shouldn't change color.
Mark, if the time saver made the inside of the rod look like lead, the part line would be a different color.
Herm: SO, you just thought you could slip that A rod past me? I am still watching. Dan
Y, don't you just get a life Dan.
I knew I should not have used the flash on the "A" side!
You said a "3/8 fine fits loose" and the hole is 10 mm. I've just been through this metric/imperial thing on my milling machine where the wrong one sort of fits
I was just rereading your first posting
1. You said "the flash needs to be cleaned up" if these are the shells that seem to be offered, then by "cleaning them up at the part line" you have just ruined your new shells. Shell bearings are always a bit "proud" at the part line. This ensures that they are squeezed tightly in place when bolted up
2. You mention torquing to 75 ft lbs when they say to torque to 45 ft lbs. Why???
3. Also mentioned is that the socket you bought fit loose. This should not be. If the bolts are metric they need a metric socket
I think these bolts would be a modified shoulder bolt, where the threads are smaller then the body of the bolt.
1 Babbitt bearing not shell/insert
2 That was the torque needed to break the bolt free out of the box.
3 Not metric, tried that. I stuck the metric in because they were some of the only readings on my caliper that made any sense as I don't have a build sheet to go by.
Update on babbitt and bolts.
Talked to Don Snyder. This is the same babbitt they have been using for the past several years with no problems.
The bolt is fine to use for setup. After they have gone through several run/heat cycles then they would need to be replaced in the future when taking up the rods.
Mark, I am sure they have been using the same babbitt, but did you ask him what kind, if he knows?