.030"-.004 rod bearings
 

Did ford or any aftermarket manufacturer, ever make .030" -.004" 81A 6211 full floating rod bearings? I know Ford made .030"-.008", but I'm looking for something a bit smaller on the o/d.
Long story; I'm building an engine and supplied everything to the engine balancing outfit to balance; all nos stuff, apart from the crank which is ground .030 under on the throws. He rings me advising the rods were mismatched weightwise too much, and asked if I had any more. I sent some more, although they were nos, they were a bit rusty in places....In due course he rings me telling me the job is done. When I get there to pick up the job, we're going through everything, it's all good until he says we bead blasted the rods. WTF!!?? i don't believe in bead blasting engine components; if you examine the surface with a microscope you'll observe abrasive material imbedded into the surface, which can potentially come loose and circulate through the engine in the oil doing untold damage, however, the bigger issue in this case is that the big end of the rod is a bearing surface; it rotates/reciprocates on the o/d of the bearing, and is now of a bead blasted texture. I pointed this out to him, he agreed they had stuffed up! So, now they are going to run the big end of each rod through a Sunnen hone to provide a suitable bearing surface. I told him I can allow .001" oversize [don't really want to run even that much, but fear it's going to take more than .001" to clean up the bearing surface].
There is a reason I use nos stuff in my builds...unstressed, and those parts are to factory specs. The only way I can see to remedy this particular situation, is going to be to hone the rods out to a size to suit rod bearings with an oversized o/d. I don't really want to have to hone brand new o/s stock conrods out .008" in order I can achieve factory clearances. I mean, why? brand new rods having to go out to maximum oversize through the incompetence of a 'professional' machine shop.
In my opinion, the only 'real' way to do this job properly, would be to balance up another set of rods to the same specs, as what has already been done. I'm in New Zealand, all the components in this engine have been imported from the USA at considerable expense, including two sets of 21A con rods in order to get a matched set.
Alternatively, import a set of rod bearings that are oversized on the o/d and size the existing rods to suit [which are still contaminated with imbedded abrasive material with the potential of coming loose].
Any helpful comments? Thank you, rant over.

Re: .030"-.004 rod bearings
 

Brian I have had the exact same thing happen with my balancer dude. Only I have found even the NOS 21A rods need resized. I have my own Sunnen rod hone and had sized and polished the rods before taking them to the balancer so I were super pissed. Fortunately he barely touched the polished surface. So I had to resize and repolish them. When I resize NOS rods and when I corrected these rods all I do is take the caps off and hand sand the mating surface on a piece of 180grit sticky that I have stuck to a flat machined surface. It takes very little and NOS rods can be as much as.0015” too big. After hand sanding very carefully and rotating cap end to end during sanding I now resize correctly the wrap 1600 grit wet and dry sand paper around the honing mandrel and polish bearing surface. It’s actually not that big of a deal and doesn’t take long. Hope the helps at least with the blood pressure. lol. Holler at me if you have any questions.

Re: .030"-.004 rod bearings
 

I agree with Tony. As a matter of fact, some of the worst rods I ever used in an engine were NOS ones. (I had to recondition them). I too have a Sunnen hone and I never install any parts in an engine that have not been thoroughly mic’d and checked to be within factory tolerances. I probably have several sets of NOS 21A rods if you need to go that direction.

Re: .030"-.004 rod bearings
 

Yeah, I see no reason to oversize the big ends and then have to use weirdo bearings that are impossible to find.

Have them resized and properly polished (to STD) and be good to go. Also, don't be afraid to go .001 larger on the big end - it helps the bearings float and is not a bad idea in the least.

Re: .030"-.004 rod bearings
 

I would think if you needed a microscope to find grit it wouldn't cause any damage if the floating bearing surface of the rods are cleaned and installed to factory specs. Also if any grit came loose it would be caught in the filter if you are using one. I assume you are using a filter (Air & oil) with how careful you are being. I would use a few swipes of 600-800 grit wet or dry paper and install what I had.

Re: .030"-.004 rod bearings
 

We have all those 2 size od and id bearings.

Re: .030"-.004 rod bearings
 

From my experience with any thing related to NOS Ford parts especially connecting rods in my opinion what we get are actually original factory rejects. The finished tolerances were not up to the standards for engine assembly at the time of production so these rods were simply put aside. I expect Ford did not destroy these parts. Eventually from that point on these NOS parts began to float around until someone who ends up with the part is finally going to use it. Expecting a nice part but sadly discover that's not the case.
Ronnieroadster

Re: .030"-.004 rod bearings
 

A highly probable scenario. I believe this is possibly the case with NOS French blocks. Myself and another friend that has built several French blocks have found they have substantial core shift so were possibly pushed aside as seconds back in their day of manufacture. Also NOS pistons that were made years ago back and been on the shelf for years always need pin bores honed from being too small in my experience.

Re: .030"-.004 rod bearings
 

On the NOS connecting rods, I found that the ones that were packaged by Ford in cosmoline have tended to be pretty good. But with anything like this, you have to use a precision dial-bore gauge to really check them out. Also, the ones packaged from Ford as a set, tended to have better balance between the set, than loose rods that somebody put into a set.

Re: .030"-.004 rod bearings
 

So maybe that’s what NORS means. New old reject stock. ;)

Re: .030"-.004 rod bearings
 

I never thought of it that way, but seems logical. I'm sure there are goods blocks within the bad. Various guys have used now for going on 30 years.

A few years back, So Cal had that auction where there were literally hundreds of complete French motors. I highly doubt any military would spend time on tearing down a motor to a bare block to rebuild it when they had ready builts waiting to go.

Re: .030"-.004 rod bearings
 

Sometime back I was going to post this question but thought everyone would respond with "dummy use the new stuff". So, I have a 49-53 Merc for a future build. The engine had little ridge, and everything is still std. I have the original rods and nos rods from Barn Find. The used rods would need recon, new rods need checking, and either would eventually get balanced. I'm interested to hear opinions on this. Thanks guys.

Re: .030"-.004 rod bearings
 

If the NOS rods checked OK I would use them over the old, they would be less fatigued.

Re: .030"-.004 rod bearings
 

Thanks for the response. that's what I kinda thought. We'll see if anyone seconds that opinion.

Re: .030"-.004 rod bearings
 

If you can buy or use a set of NOS 49-53 rods, I'd go that route. Obviously have them checked at the shop as well - just to make sure they are in spec for roundness, straightness, etc.. Also, have the engine balanced.

Re: .030"-.004 rod bearings
 

I've never fooled around with the pre-8BA engines, but isn't there a problem with one hole vs. two holes in the rod journals?

Re: .030"-.004 rod bearings
 

You are correct. Using 8BA rods requires using 49-53 crankshaft with two oil holes per rod journal.

Re: .030"-.004 rod bearings
 

Us guys down under are fortunate in many respects inasmuch as our early Fords were sourced from Canada. Canadian engines from 45 onwards, used lock in shell bearings and had double drilled journals to suit, those particular bearings are hard to source these days, but one can run full floaters on those double drilled cranks using 21A or 29A rods to suit. Alternatively 8BA rods and bearings can be used on the 239 cranks.
In my case here, I'm using a 239 double drilled crank, offset ground 1/16" to 1.969" [.030" under 221 journal size]to give me 3 7/8 stroke, and using the corresponding 81A-6211-Q full floating bearings. this will give me a 1/16" 'pop-up' using stock 239 pistons, and I will configure the heads to achieve optimum 'squish'.
My initial post was a bit hasty; I was envisaging a bad scenario, but upon receiving the conrods and measuring them, they are .001" oversize, [don't ask me the dimension- I don't have it now], but I managed to set all the clearances- get everything fitted up nice....
Next job is to redome the heads to suit the pop up and piston dome- these pistons are stock Ford and have the 'pointy' dome- I've made a cutter to suit.
Things we do! whew!

Re: .030"-.004 rod bearings
 

Hey Brian, sounds like a fun project . . . a little sneaky hot-rodding going on there! LOL

Best of luck with your build!

Re: .030"-.004 rod bearings
 

Thanks Dale