When bolts loosen up...

[Andrew Mace]

Trying to track some rear-end noise and vibration last week (SEE: Parts rant! Part II), I’d discovered that three of the four nuts and bolts holding the LH driveshaft flange to the differential flange on my '62 Herald were slightly loose. At the time, I simply tightened the three (the fourth didn’t seem to need tightening) and made a mental note to pick up some new nyloc nuts. I did that today and set about replacing all four nylocs. In process of doing so, I spotted what looked like a hairline crack on the differential flange, borne out by the fact that the flange actually wiggled a bit as I touched it. I knew this was NOT a good thing, and it was likely the reason that some vibration had returned. I also knew that there was probably no option but to replace the inner axle/flange assembly complete.

I undid all four bolts, the rear radius rod bolt, and I started to remove the big nyloc on the lower shock mount. For some reason, it was being very difficult…right up to the moment that the threaded stud snapped off. (Of course, that’s an integral part of the vertical link, so now I’ve no choice but to replace the vertical link. That will prove to be a challenge, since the bolt seems rather nicely seized, and the link doesn’t seem to want to pivot much. Oh boy.)

At least the top bolt through the spring eye came out without drama, and I got the drive axle out of the way enough to remove the inner axle, revealing the picture you see here:

It’s hard to say for sure, but I suspect that the strain of the three loose bolts was enough to stress-crack the flange around the one bolt that had still held tight. It’s a moot point, though, since the damage is done and bits need to be replaced. There’s just one slight problem: the differential currently in the Herald is from a 1970 Spitfire, which means it has the small flange but the thicker stub axle. Naturally, it wouldn’t have been a typical earlier Herald/Spitfire differential with the smaller stub axles; I’ve plenty of those. Somewhere in the barn is – or should be – one other small flange/thick stub axle differential. All I need to do is find it. It’s either that, or I grab one of the earlier differentials, pull this one out, pull off the front mount that I’d put on it to mount to the early-style chassis, bolt it all back up and hope that whatever diff. I choose is a decent one!

Oh, and this is the only car I have running at the moment, so I hope I can somehow get this all done tomorrow…if it doesn’t rain too much. Figuring it would be a quick job – I should know better after over 40 years of playing with these cars – I didn’t bother to drive it into the barn to work on it. Instead, it’s sitting in the middle of my driveway....

 

[lbcs_r_fun]

For a quick fix cut a backing plate out of steel plate, using the flange as a template, drill the four holes and off you go, that is, until you find another.

 

[HerronScott]

Sorry to hear about your problems Andy. I almost dread working on any of the DD cars these days since it's always in the driveway given my lack of a work garage (I'd be happy with a barn!).

Hope you can resolve it quickly and if you need any Spitfire parts let me know but mine are all going to be 1968 or earlier.

Scott

 

[TomMull]

It’s hard to say for sure, but I suspect that the strain of the three loose bolts was enough to stress-crack the flange around the one bolt that had still held tight. It’s a moot point, though, since the damage is done and bits need to be replaced.

Moot but interesting (at least to me as I don't have to fix it). The old chicken or the egg. Properly torqued bolts and nuts do not usually come loose. Possibly somehow misaligned or perhaps a piece of debris underneath at one time? Good luck finding the spare. Any chance the old one could be tiged and trued up? Tom

 

[Andrew Mace]

Moot but interesting (at least to me as I don't have to fix it). The old chicken or the egg. Properly torqued bolts and nuts do not usually come loose. Possibly somehow misaligned or perhaps a piece of debris underneath at one time?

I was surprised myself. In the 40-odd years I've been playing with these cars, I can honestly say this is the first time I've ever had nylocs loosen up. Yes, they had been reused several times, but they still had enough "life" in them that they could NOT easily be turned by hand until the threads were through the nylon insert. I almost wonder if the differential flange had fatiqued and cracked first, causing the other bolts to appear loose?

The more I (over)think about this, I suppose it's possible that there was additional strain due to the fact that the vertical link on the drive axle does seem to be rather seized up and NOT pivoting properly?

Any chance the old one could be tiged and trued up? Tom

Interesting thought. I'm sure it's possible, but I don't know if it's worth the effort. I'll save the old bits as "trophies" if nothing else, but I might ask my welder friends about it just for fun! It is a shame, since the rest of the assembly is in pristine condition.

 

[TR3driver]

Sorry to hear about your problems, Andy.

You do realize, though, that this is karmic retribution for all the "parts rant" posts?

 

[Andrew Mace]

Sorry to hear about your problems, Andy.

You do realize, though, that this is karmic retribution for all the "parts rant" posts?

Yeah, it's probably that...and the fact that my son commented yesterday on "what a trouper" my Herald has been this past year"! It really has been, carrying me through a tough upstate NY winter as my only transportation and even bussing both him and his sister around a bit when their respective cars died and replacements were sought out!

Funny, though, that both of their previous cars could've been repaired, but both at very high costs. (What a '99 Jetta costs to maintain and repair is horrendous, and while we're keeping the car for now, his '81 Subaru just is very difficult to find parts for here in the Northeast.) By comparison, what it will take to get this Herald back on the road yet again amounts to "pennies" (pence?)!

 

[71MKIV]

in the airplane busnezz, the nyloc portion of the nut is NOT to keep it tight. The torque on the bolt is what's supposed to keep the nut tight. The nyloc part is only there to keep the nut from bouncing around in something important after it has fallen off. Another important thing is for the nyloc part to be effective, you must have at least a thread and a half showing outside the nut. The fact that three of the bolts where loose, and the bolts were still there, the nyloc did their thing. I hear the Triumphs with that style rear suspension get a little squirrelly handling with the axle disconnected.

 

[BRSLimited]

Andy, if you find yourself needed another vertical link and axle I've got several of them here.

 

[Andrew Mace]

Well, as Canned Heat used to say, I'm "back on the road again"! Admittedly, one of the repairs is of a temporary nature; I had to scrounge around for a rear brake hose to use until the one I ordered shows up, hopefully tomorrow. Other than that, thanks to my dwindling but still fairly extensive stock of used bits and pieces, my biggest expense was $14.01 for a five-pack of metal reciprocating saw blades that I needed to cut the bolt holding the vertical links (both the bad one on the good axle and a good one on a bad axle)! I had a trunnion bushing kit that also made do for now (new ones of those are also on their way).

My biggest fear was using the one differential I found. It's early enough to have a drain plug (very nice), but upon opening same only a bit of water drained out. However, everything inside still looked good, so it was filled with EP 90 weight and installed. I panicked briefly when I started to remove the other one, realizing the exhaust system was in the way. But since it was only eight months old, it came apart nicely and was out of the way.

I got everything buttoned up around noontime and took a quick test drive...and all seems well. The diff is quiet and smooth, thankfully, and everything else seems to be what it should be. Ironically, this had all started in replacing some old nyloc bolts on the drive axle flanges. Even more ironic (if that's possible) is the fact that I've now reverted to the old ones. In removing the four new ones I put on, they started rounding off badly. Apparently, they're not quite the quality I thought they'd be, and they're the shorter ones to boot. The old ones appear to match in size the "heavy duty" ones McMaster-Carr shows on their web site, so I think I might be ordering a supply of those unless I can find them locally. (We have one great industrial fastener supply store in the area, but it's a pain to get to and not open weekends.)

Needless to say, I'm a "happy camper" again!

 

[booley]

nice work, I knew you could do it
are you referring to Woodward or Douglas Industrial?

 

[Andrew Mace]

Douglas, in Watervliet. Neat place to visit. My son and I had some fun there last summer when we were putting together his Subaru EA-81 engine. After trolling the Internet for various odd types of Loctite, it turned out they had every conceivable kind of Loctite (and several odd types of PB Blaster) right there on a shelf/wall display!

 

[booley]

Douglas is a cool store, never knew they weren't open Saturdays.
you ever try Woodward (off I90 exit 5) though I can't imagine they'd be open Saturday either...

 

[Andrew Mace]

Hmmm...maybe it was a summer hours thing? I should call, huh? :wink:

Never tried Woodward, but I might just do that as well. Thanks for the tip!

To everyone else: this is how you KNOW you're a hopeless car guy/gal...when you can talk enthusiastically about FASTENER SUPPLIERS! :laugh: