Dealing with seized items

Technical Miscellaneous and universal issues
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Hi all,

I thought I’d share experience gained from dismantling my 1989 Mille GT. I had lots of fun with items that were seized solid.

First and most difficult was the bolt that holds the timing chest cover into the frame. It sits just behind the front wheel and so gets all sorts of road crud thrown onto it. It’s a well-known problem area - and these covers are very difficult to get hold of, so you don’t want to break them. So - first, I tried just using a breaker bar on the nut at the end (easy) and the head of the bolt. I gave up here because I was frightened that the head would shear off. I tried a rattle gun, which often works, and then my SDS drill, on non-rotating hammer mode at the other end. No movement whatsoever. I spend the thinking time dismantling lots of other bits and bobs, and once I’d removed everything apart from the frame itself, I worked out that I could hinge the frame over the engine. I’d already tried heat, heat/quench, penetrating oil, acetone, ACF50 on the bolt, but all to no avail. I’d watched about 20 YouTube videos on this sort of thing, but to be honest, they weren’t very helpful.

Next step was to remove the gearbox (with the frame hinged over the engine, this was fairly easy), and then I undid all of the timing chest cover screws, (including the two that were hidden!) and pulled the engine back. So now I had just the cover and the frame. So, next, I did as thorough a clean as possible of the 4 places where the bolt interfaced with the cover. The outer edges were almost impossible to get to, but the bolt is exposed for the centre portion, so I focussed on cleaning out the ‘slot’ and filled it with penetrating oil and let it soak. Still… no movement whatsoever!

We’re now into the Sunday of the third weekend working on this b******!

Next, blowtorch on everything - getting it nice and hot, and then I tried again with the breaker bar, hanging off it not really caring any more whether the head sheared off. There was the tiniest of movements and so I reversed it, and then spend about half an hour moving it one way and the other until I could turn it - very stiffly - through a whole rotation. I then tried whacking the threaded end of the bolt, but it was still too tight to move at all. I figured that maybe the middle section of the bolt had corroded, making it too big to go through the casting. So, I cleaned that up as best I could and tried again. No movement, still!

Last resort… I asked my long-suffering wife for help. This is what we did:

  • More penetrating oil
    More heat
    I got the bolt very slowly turning (it still needed the breaker bar, as it was very stiff)
    She hammered the threaded end of the bolt as I turned it

Hurrah! We had some lateral movement! Although I had to file down the end of the bolt where the hammering had spread it, it only took about another half-hour before it was out!

Next, the post-mortem. I could see quite clearly traces of copper grease on the bolt, so someone in the past had done the right thing as a preventative measure. But the bolt’s a tight fit and so I guess that the copper wasn’t actually where it needed to be. So, it’s probably worth loosening the bolt every year or two, just so that you know that you cam remove it if you need to. My take-out on the removal itself though is that heat really works, and you have to be prepared to use quite a bit of brute force. Also - and this is probably significant - I realised that if the part you’re trying to free is covered in dirt or grease, then that will effectively seal the thing so that your penetrating oil (or whatever) can’t get in. So, I think the cleaning really helped. It’s hard to over-heat if you’re just using a butane blow-torch, so don’t be too worried about over-heating things (but you might destroy any adjacent seals, and paint finishes will suffer). When you get to the end piece, celebrate when you get even the slightest movement - you’re on the home straight! back-and forth movement will get you there.

My last piece of advice is to stick with it! Change your approach if it’s not working, and know that you can win.

There’s plenty more - but that’s for another time.

Nick

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Part 2: Engine bits and bobs

Whilst I was thinking about the timing chest cover, I started dismantling the engine, starting with the cylinder heads. I’d firmly recommend reading the archive at My Old tractor - it’s full of really useful information. https://www.thisoldtractor.com/guzzitech.dk/gb_en_complex-technical.htm For the engine strip it’s worth reading both the account without pictures, and the one with pictures. There’s lots of embedded information there such as hints about what works, and also torque values.

So - breaker bar in hand, I set about the head bolts, having already taken off rocker arms, etc. five out of the six came out without any problems :slight_smile:.

One of the sleeve nuts (they’re down a hole under tough-to-remove caps) wouldn’t budge. In trying, I broke my 3/8" to 1/2" socket drive adaptor. It sort of tore apart. Interesting, but annoying as well! So, having bought another one, I tried it with the rattle driver - it eventually came out - but be warned about working at this very hard - I managed to distort the threaded hole that the (essential) cover screw fits. Sort of luckily, I’d planned to replace the head because it had some broken fins, but it would have been really annoying if I’d wanted to use it! I should have worked harder at trying to free the sleeve nut as the My Old Tractor archive material suggested.

Apart from that, the engine strip wasn’t too bad - at least in terms of seized nuts and bolts. You just have to be prepared to get very, very dirty! It’s incredible how filthy everything was - and I’d tried to clean as I went.

OK - more another time.

Nick

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This doesn’t go on for ever - but I thought my wheel experience might be worth sharing…

My wheels have akront rims and stainless spokes. Didn’t look as thought they’d had much attention since they were new. Lots of authentic patina, if you like. Anyway, I was pleased to have them.

Looking at these from closer than about 5 yards, they’re spoiled by having steel nipples (where the spokes join the rims). They were probably galvanised back in the day, but now they were just blobs of rust, so I thought I could just replace them with nickel plated brass ones. Foolish child - what was I thinking? They were double-corroded - dissimilar metal corrosion between nipple and rim, and plain rust between nipple and spoke thread. threads of the spokes.

After about 5 minutes, I realised that some of the spokes would end up being damaged, and so decided it was probably worth re-lacing the wheels with new spokes. But I really did need to get samples out so that I could measure them in order to place orders for new ones. It took me a whole day of working at the least bad of them before I managed to get the nipple ends of three free. A couple of the nipples were actually shiny plated, so these were the ones I tackled. I didn’t manage to save any nipples at all.

NExt morning I just took a disc cutter to the 38 other spokes on the rear wheel. So now I had rim and hub separate. The rim ends needed heat and a bit of briute force to free the nipple from the rim, and then they fell out. Only took a morning, those 38. But at the hub end (which ought to have been easy!), the spokes were completely locked solid in the hub. I worked out eventually that to free them needed:

  1. A squirt of penetrating oil
  2. Grip the spoke with locking pliers (VERY tightly)
  3. Heat the hub with a blow-torch until the penetrating oil disappered into the interstice between spoke and hub
  4. Twist the spoke hard, at which stage there was a little puff of white smoke and I could twist it in the hole.
  5. Work at it for a few minutes, until it would move length-wise. This usually meant that I had to hammer on the locking pliers before it would move.

I did manage to forget that the cut-off spokes were sharp as razors - had a nasty cut (now healed). But that rear wheel took me about 5 hours.

The front hum was easier. I think my technique was honed by that stage! Fo about an hour and a half later, I had 2 hubs, 2 rims and a carrier-bag full of cut-off spokes.

… only to discover, on examination, that the rear rim was cracked, between the nipple holes. B****r!

Anyway - the lesson here is penetrating oil, plenty of heat, appropriately directed force and sticking at it.

Getting the bearings out of the brake disc/ bearing carriers was pretty straightforward - just plenty of heat, and a whack on the bearing spacer via a block of wood with a hammer.

That’s about it. I don’t want to remember any more siezed objects!

Cheers,

Nick

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… and then there was the exhaust studs.

Actually, not too tricky. I’m more used to heating things up nice and hot now. So, 3 of the 4 came away quite nicely. All I did was back up a couple of nuts onto the studs, and then heated them up before I wound them out.

the 4th was a right b****er though - the stud itself snapped between the two nuts. So, I took it to an engine services place in Bath (Hurley engines and garden machinery), where it waited for an hour or two amongst the lawnmowers before they took it out. I have no idea how they did it, but presume they probably have an induction stud heater, since they didn’t leave any witness marks on the stud and it came back to me loosely assembled into the threaded hole. (£18, so reasonably cheap - and much less stgress than working on it for hours!)

I think that’s it for now.

Nick

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Hi nick HM. Just joined the MG club and reading through a few things on the club website. Well done on your report of seized threads.
I worked for an engineering company in Hull, Yorkshire in the 1980’s and got to do field thread repair work in the area- broken studs, helicoiling and thread rolling.
Lorry cylinider head bolts where a really tough metal to drill out, a rotten job when a few need doing.
Your best bit of advice was to periodically remove fasteners and lube them up with an anti-seize so they don’t seize up in the first place!
It’s not always a good idea using stainless steel bolts to replace cadmium plated ones, simply because they can seize up due to corrosion according to the dissimilar metals (according to the electrode potential series). Stainless steel bolts are harder to drill out compared to mild steel ones.
Hey I’ve got a snapped stud in my alternator cover still to remove.

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Hi Fairytale - and thanks for reading. I really wrote the piece as a cathartic activity, having spent so much time hanging off fasteners and worrying about damaging the bits I was taking apart. It was definitely a strong learning process, and I’m now far more confident. But, as you say, it does seem very important to periodically remove and lube. But I also see that even anti-seize isn’t a complete answer - win some places, it had formed a barrier against the penetrating oil I was using.

This bike is now mostly back together - another thing I’ve learned is that it’s possibly not a great idea to sort everything at once (though in places I was sort of forced to). I think in time I’ll write a ‘putting it all together’ report. That’ll be fun. But I’ll only do that when it’s running properly and has a MOT.

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Did the first ride yesterday with my new battery in. Did a 3-4 mile circle. Stopped the engine outside my house. It restarted fine. Got cocky, went a a straight line for 2 miles, did a U turn and it stopped. Wouldn’t restart. After several tries it ran on one cylinder to get me back home…

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Welcome to the club, then:>>>

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Excellent thread.
Well done and a v useful reminder to loosen me bolt off, it has been a while
:+1:

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Interesting tales of difficult and downright bloody awful studs/nuts etc that refuse to shift. After 40yrs in engineering the most helpful penetrating fluid we ever found in our workshops was diesel, not only does it stink but it will creep down the most rusted of bolt holes, if you can overnight soak theres not much it wont loosen and then attack with heat :+1:

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Bulldog BDX is the new king of lubrication and for unseizing studs and nuts. Wonderful product , you can look for it online and see reviews

Gino

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Great advice. Heat and patience win the day. A 50/50 mix of ATF and perfume free acetone (nail varnish remover) works well as a freeing agent.
Seized front engine bolts are legendary in Guzzi world.
This is the time of year when Guzzisti check and lubricate them. I pack the centre section of the cover with grease and clean it out & replace at the winter at service.

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Well worth putting your observations to date and on the rebuild into an article for Gambalunga. Plenty of interest in these projects particularly developing confidence in having a go.

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Thanks for your useful thoughts. I’ve one new one - keep it simple!

I had a numberplate screw that had sheared. Thought I’d use an Easy-out (or wharever they’re called now). That’s a tricky ‘drill a hole and then use the tool’ that relies on it gripping the hole - it has a coarse left-hand thread, so when you ‘unscrew’ the tool, it actually burrows in and grabs the hole you drilled.

BUT - the simple solution was to use a Dremel tool to cut a slot in the shank that was left and then unscrew with a flat-head screwdriver. It worked like a dream, and only took a couple of minutes. So - always try the simplest solutions first.

By the way, I did try using Diesel, ATF (auto transmision fluid) and acetone on the engine bolt, but it didn’t get through - probably because there was sufficient residual guck to prevent it penetrating. Maybe I could/ should have given it longer and/ or scraped out as much as I could with a pin. Either way, you just have to keep trying!

Good luck to all and any who have to deal with siezed fasteners - they to take some tenacity! I must say, though - for siezed exhause studs, the induction heater solution (in my case, via paying for the stud to be removed) seemed an ideal way of applying heat - it seemed to take them no time at all. So, paying someone else for their expertise seems also a solution!

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+1 on induction heaters. A lot cheaper than trying to find a replacement cylinder head should other approaches go awry👍

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Possibly talking ———— I have encountered this , it occurred to me that the bolt should be a stud ? Ie remove one nut n tighten the other, effectively a puller with considerable force ie tons so high tensile stud required with slightly extra thread Borge ends ?

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