Helicoils How To... (And How Not To!)

I got home today to find my Helicoil kit waiting on the doorstep. I threaded the alloy rear oil seal housing at the weekend and decided it'd be a better idea to repair it rather than buy a new one and risk threading that too! It's cost efficient too, a new housing would've been £20 whereas the Helicoil kit was £15! I got my kit from Chronos Engineering because they sell kits that contain everything you need so you don't have to spend ages searching for obscure size drill bits.

The kits are specific to a certain bolt size and contain around 25 Helicoils, a drill bit, a tap, an allen key, an insertion tool and a small drift all in a nice blue case!

So here's the problem. Basically a classic case of Triumph using the wrong fastener in the wrong place. The alloy is really very soft and it would have been better if Triumph had used a UNC thread like they did on some other alloy parts such as the intake manifold. Instead they used a UNF thread on both this and on the engine front sealing block.

First thing to do was to drill the threads out. I checked the depth of the holes and wrapped a bit of tape round the drill bit from the kit so I didn't go too deep! The alloy was very soft and drilled nice and easily.

The next stage of the process is to thread the hole for the Helicoil insert. The kit comes with the tap but you'll need a tap wrench if you haven't already got one. I borrowed a tap holder from my Clarke Imperial tap and die kit and that worked a treat. With tapping it's always best to take it slow and keep the tap well oiled but when the metal is as soft as this, you can go pretty rapidly!

Once the hole is tapped to the bottom you can remove the tap and run it through a few times. I cleaned the swarf out with light oil from an aerosol to clear it.

Inserting the Helicoil is very straightforward. It's basically a spiral of metal that has a small 'tang' sticking into the middle at the bottom. To fit it you use an insertion tool that is basically a drift with a slot in the end which engages with the tang on the Helicoil. The one in my kit has a depth stop so you can sink the coil down to a set depth. This is secured using a grub screw and the allen key from the kit.

With the Helicoil in place, all you need to do is knock the tang off. The tang is weakened and should knock off pretty easily using the drift from the kit.

This worked well for me on one of the holes but not on the other! On the one hole the drift didn't seem to knock the tang of very cleanly. The last thread ended up sticking out slightly and when I screwed in a bolt it seemed to push the thread down underneath the bolt. This meant that the bolt wouldn't screw fully home and left the Helicoil in a right mess! I had to get it out!

I thought this would be near impossible but it was actually fairly straightforward. You've just got to bend out the top thread until you can get a pair of pliers on it and then the whole thing will unscrew just as easily as it went in. Once the mangled Helicoil was out, I cleaned up the threads again and fitted a new Helicoil. This time I snapped the tang off by gently wiggling the insertion tool forwards and backwards. This worked a treat and after running the Helicoil through with a tap I was happy that the job was done!

Clutch Stuff

I might as well rename my blog 'Will's POR15 blog'! I've been using huge amounts of the stuff over the last month! Firstly there was my alloy bellhousing which I painted inside and out, then there was the clutch release lever and then finally the gearbox casing which I painted up to match. The grey doesn't seem to go on quite as well as the black but the finish is very good all the same.

Once the bellhousing was painted I refitted the steel insert that the release bearing carrier slides on. After doing this I realised that something wasn't quite right. Canley Classics website describes the insert as 'Part 122566 - Bellhousing Centre Her/Spit (Scroll Type)' but when I took it off there wasn't any kind of oil seal on there! Fortunately the situation was easy to solve with a later type bellhousing centre that takes an oil seal.

While I was there I thought I'd renew the slave cylinder pushrod and the pin that holds it in the release arm. Incredibly, there was more than 2mm of wear in these two parts! The new pushrod was a bit fat and needed the attention of a bench grinder but was otherwise easy to fit. Once I'd done that I tried to fit the release lever into the bellhousing and ran into another problem!

Basically, the clutch release lever just wouldn't move smoothly over the bellhousing centre. This seemed to be due to the inside of the bellhousing being slightly cast wrongly. I have to say that the general quality of the alloy bellhousing is pretty poor and I suspected when I first saw it that it might need some 'altering'. In the end though, I decided to just grind a bit off the bottom of the release arm instead. This gave the necessary clearance and the throwout sleeve on the arm now slides smoothly like it should!

While I was in a painting frame of mind I painted the engine back plate and the drivers side floor in POR15. The drivers side floor is a mess and has a couple of plates welded on and a few tiny holes. I'm aiming to replace this in the near future but for the time being I just want to stop it getting worse so painting is the answer!

I did actually buy an alloy engine backplate but I don't think I'm going to use it. I've heard tales of the alloy ones cracking around the bottom bolt holes and I sure as hell can't be bothered to sort that out in the future so I'll be sticking with steel!

I've had one slight hitch with the engine this week. I was just fitting the renewed rear oil seal to the back of the sump when I stripped the threads in the alloy housing. This was a right pain because my brother came to visit this weekend and I had hoped to have the gearbox and engine ready to go back together. It'll have to wait now until I've helicoiled the threads. I've not done this before but it looks straightforward enough. I've ordered a kit from the eBay shop of Chronos Engineering. Hopefully that'll arrive in the week and I'll be back on track next weekend!

Gearbox out!

This week has been a busy one! I started the week by fitting one of those 'Stant' lever radiator caps. This is straightforward enough but, if you're thinking of fitting one, you need to get a few things right. Firstly, the pressure rating has to be right (13lbs) and, secondly, it has to fit under the bonnet! I checked this very carefully before dropping the bonnet down for the first time!

The next job was a big one! The gearbox needed to come out so I could replace the engine's rear oil seal. I won't bore you to death with the details of how I got the gearbox out but it did involve a hell of a lot of brute force, wood and jacks. Believe it or not, I did it all on my own too!

The oil leak had made one hell of a mess. The inside of the bellhousing, bottom of the gearbox and the underside of the car were absolutely caked in oil and dirt!

The standard cast iron bellhousing weighs nearly as much as a chest freezer! I bought an alloy replacement from Moss last year and started preparing it to fit. It's not the best casting I've ever seen but I think it'll do. I've painted it inside and out and I've gone for grey POR15 this time to show up any oil leaks! It's a very similar colour to my workshop floor!

The seats are looking good. I've bought another seat foam set from Owen at Park Lane Classics. I haven't had time to do any more work on them though. I'm waiting till the gearbox is out of the way and my workshop is less dirty before I start work on them again!

Progress In The Last 6 Days...

I've been working far too hard at work this year! I can't carry more that 5 days over to the next financial year so I've had to take four days off this week! It's been nice spending some time on the car and I've got a good number of the little jobs done.

On Saturday I had 'fun' with the water pump. I fitted this last week but I thought I'd better tighten up the nuts properly. You can't get a socket on these because of the pulley so I used one of my ratchet spanners. This was going well right up until I did up the last nut. I felt the nut tighten and then suddenly slip. I was gutted! My first thought was that I'd stripped the thread in the alloy water pump housing. Fortunately, I was lucky and it was just the stud! I couldn't get the stud off in situ so I had to remove the water pump.

I got a new stud in and made myself a new gasket. If you've never made a gasket you should try it! It's really easy and it saves loads of time. You can use card from a cornflake packet if you're desperate but the pukka stuff, which I use, is 'Flexoid' paper. It's really cheap on eBay and it can really get you out of a jam! All you need to do is trace around an existing gasket or place the paper over the flange and rub it over with a dirty finger to highlight the edges and then cut it out. You can make the holes by hammering a bolt into the paper. Easy!


Anyway, once I'd smeared a bit of Loctite 5926 gasket sealant on the faces I started bolting the water pump back in. This was all going well right up to the point where something threaded again! I couldn't believe it! This time it was the nut! I got a replacement and gave that a go. This time the stud threaded!

Something was definitely going on here! Once I looked into it, it was obvious what the problem was - the studs were too short! There weren't enough threads of the stud in the nut to take the torque of tightening. Once I'd realised that (and made another new gasket and found some longer studs) I was back in business. Sorted!

On Sunday I went to Stoneleigh. It was a brief visit again for me this year but I saw a few familiar faces and met a few new ones. There was loads of stuff for sale and I saw quite a few bargains. I really, really, wanted the mint bonnet that was for sale at £180 but I just couldn't have got it home in the back of my Golf! Instead I settled for picking up a few useful nuts and bolts!

On Monday I got my Nippon Denso alternator fitted. I'm still figuring out how the hell I'm going to wire this up but at least it's physically fitted in the car. I used a Canleys fitting kit. It was good but I'm going to replace the adjusting plate with a couple of rod ends in the near future.


On Tuesday I spent the day fixing the brakes on my Golf. The pads had seriously worn down with all the miles I'd been doing for work. In one case the friction material was down to 1.38mm! I decided to replace both the discs and pads as the discs had a massive groove around the edge because they seemed to be slightly oversize. I ordered replacement parts from Euro Car Parts and set about doing the job. It was all going swimmingly until I realised that the drivers side caliper wasn't sliding properly. Unfortunately the metal sleeve that the caliper slides on was seized solid on the caliper bolt and I had to destroy it to separate the two. Amazingly, my local VW dealers had the part in stock and I managed to get it back together on Wednesday morning!


On Wednesday afternoon I decided to finish off my anti roll bar links. I made my own out of rod ends from McGills Motorsport. There was a bit of work needed to get them fitted. I needed to drill out a sleeve to make a spacer and source some longer bolts for the wishbone end. Drilling out the sleeves was easy thanks to an 11mm cobalt drill bit from Namrick! Sourcing the longer bolts was tricky though. I couldn't find any online and eventually I had to get out the Yellow Pages. This worked out nicely and I turned some up at Nutters Fastenings in Nechells, Birmingham, which is just a few miles from where I work.


This morning I got another nice new part in the post. This time it was an alloy pulley from Rimmers. I'd heard bad things about alloy pulleys in the past. Apparently they used to be all alloy, which resulted in the keyway wearing out because of the softer material. The Rimmers one has a steel sleeve in the middle bolted to an alloy outer. Another bonus is that the bolts look like they might be handy for mounting a timing wheel if I ever want to move to a Megajolt set up in the future!

Engine Valances - Finished!

Fun with POR15!

POR15 is a really tough finish paint that is a great way to finish off loads of underbonnet parts. It leaves a very glossy and durable finish but requires a bit of care to apply. This is my quick guide to using POR15 and getting the best results!

Firstly, if you're painting something really smooth (like these aluminium radiator valances), you're going to have to rough the surface up a bit. I used a fairly fine sanding block which just took the shine off the metal without leaving any deep scratches. Once that's done you need to degrease using POR15's own degreaser. This is called 'Marine Clean' and is a vaguely greenish liquid that you dilute with water and coat the part with. This normally comes in a screw top bottle but I have prediluted mine and decanted it into an old spray bottle. After leaving to soak for a while, wash off the part with plain water.

The next stage of the process requires the use of 'Metal Ready'. This is another POR15 product and is basically a blue liquid that seems to etch the metal slightly. I guess that this contains phosphoric acid but I don't know for sure! You need to keep the surface of the part wet for a minimum of 15 minutes. Again, I have decanted mine into a spray bottle to make this easier. After 15 minutes or so you need to wash the piece again to clean off any residue.

The etched surface is slightly grey and sometimes a bit 'powdery'. This is OK! You are now ready to move on to the next stage...

You now need to be quite organised to avoid making a mess. I'd advise you to use plenty of newspaper over your workbench as it's going to be near impossible to clean up if it all goes wrong when you're pouring it! Get your brushes ready and also have some cling film and a jam jar ready. It's also wise to wear gloves because this stuff is pretty difficult to get off!

So, what you need to do is to open the tin of POR15 very carefully and either pour it or use a coffee scoop to transfer it into the jam jar. It is VERY important that you cover the tin with the cling film before you put the lid back on. If you don't you'll have to use water pump pliers to rip the lid off - trust me on this! Now you're ready to paint.

I strongly recommend using a foam brush. The POR15 starter kit comes with one or you can buy a pack of 20 for £5 off eBay. This will help minimise brushstrokes and will look neater. It goes on pretty easily. Don't stress too much if it looks a bit 'brushstrokey' as it seems to level really nicely after about 15-20 minutes. If you have paint left over in the jam jar you can seal it with cling film and use it later. Stored like this it seems be usable for a few days before it drys out.

And there we go! It should be touch dry in around an hour. Unfortunately one of the disadvantages of POR15 is that it's not UV resistant. Apparently it discolours and turns brown with prolonged exposure to sunlight but won't actually fail. In order to prevent discolouration you can use another POR15 product which is resistant to UV, such as 'Blackcote', which is what I have used here.

And that's it! You're done! One of the common misconceptions about POR15 is that you can't get it off anything. They actually do sell a thinner that you can use to clean brushes etc but it's quite pricey at around £20. That seems pretty expensive when you consider that the starter packs cost around £15 and contain 'Marine Clean'. 'Metal Ready', paint and two brushes! When I get it on my hands I find it comes off easily enough if I wash them straight away. If it dries then it takes a few days to wear off!

Going back together...

I'm slowly getting the engine back together! Just before christmas I recieved an alloy water pump housing from Canley Classics. I was a little bit suprised to see it as I ordered it ages ago and it had been on back order for about a year! Initially I was annoyed that Canleys had just sent it (and billed me) without asking me if I still wanted it, but when I checked my email I found they'd emailed me about a week before and I'd totally missed it so I can't really complain!

As luck would have it I was just about to repaint the waterpump, housing, engine front plate and pulley with POR15. I was tempted to leave the new housing in bare alloy but in the end I thought it'd look better painted. Two coats of POR15 with a top coat of Blackcote and it looks the business! It gives a really deep gloss black. Just compare it to the 'normal' engine enamel on the black in the pics! I'm going to be using a lot more of this stuff in the future! The only thing that is annoying is that it sometimes leaves annoying brushstrokes so you're better off using foam brushes. Look on eBay if you need some - they're £5 for 20!

I had a great idea with the timing cover bolts and screws - I numbered them. This will come in handy the next time I need to take them off!

This is my 'refinished' thermostat cover. Normally there is a number cast into the top. I thought this spoilt the smooth lines so I sanded it off and polished it up. Looks much better!

Seat Straps

I carried on working on the seats this week. One of the first jobs has been to tackle the sagging rubbery seat straps that run across the seat back. These are basically a length of rubbery webbing that is folded over onto itself at each end to trap the seat clip and then stapled into itself with a couple of small plates to dissipate the load. I thought these would be pretty cheap so imagine my surprise when I found out a strap kit was nearly £40! That's for one side too, so £80 to do both seats!



Clearly that was ridiculous, so I set about trying to find a cheaper way. After a bit of research, it turns out that the rubber strapping stuff is called 'Pirelli webbing'. This is available by the metre from upholstery suppliers and is very cheap. I bought mine from a company called 'Skiddaw Upholstery' and it arrived pretty much next day. The stuff they sent was a bit thicker and looked better quality than the original Triumph issue. It was a different colour but then who really cares when it's inside a seat!

The staples and plates can easily be bent out and removed from the old straps and fitted to the new ones. It's really easy and quick and the results are very good. Just remember that the old straps will have stretched a bit, so make the replacements a bit shorter. And that's it - dead easy! About 5m should do both seats and will cost a much more reasonable £11.25 + postage!

Are You Sitting Comfortably?

That's the question I was asking myself. The answer was a resounding 'no'! One of the things I learnt from the Historic Counties Run was that the passenger seat is infinitely more comfortable than the drivers seat! Hardly surprising really - Collapsed foam and ripped vinyl crudely 'retrimmed' in gaffer tape are not the last word in comfort!


I have entered the Club Triumph Round Britain Reliability Run next year and I really wanted to get the seats sorted before then so I got started! My initial thought was to get another set of seats in better condition and swap the drivers side seat base with my knackered one. Taking a closer look at my seats quickly changed my mind. Even the passenger side was completely knackered. Just moving them produced copious amounts of foam breadcrumbs! Even the metal parts of the base were thin and seriously rusted.

I decided the best thing to do would be to get some more seats from eBay and use their guts! Fortunately eBay came up trumps with a set of seats (already partly dismantled!) in Derby. I set off after work on Thursday to pick them up. They guy selling them was building a Rover V8 powered Spitfire which looked like quite a piece of engineering. I had a look at the seats in it too. They were leather and very nice. I had a look at the seats he was selling and, whilst they weren't as nice as the ones he wasn't selling, they were much better condition than mine!




So now I had something to work with I set about stripping down the drivers side seat. The backrest had already been stripped down so all I had to do was strip down the seat base. I found it quite interesting how the seat is constructed. Basically there is a very basic steel seat frame. On top of this goes a steel 'basket' which is constructed in a similar way to a shopping trolley. At the bottom of the basket is a piece of 'millboard' to stop the foam sticking through the bottom of the basket. Attached to the millboard is the sensor for the seat belt warning light. This is then covered with two big lumps of foam. The vinyl then goes over the whole lot and attaches using 'hog rings' to the wire basket. To the uninitiated ' hog rings' are basically a C shaped bit of metal that pierces the vinyl and is then closed with a pair of pliers.

I stripped the seats down and started cleaning up the metal parts. I've recently invested in a new Black and Decker angle grinder (to replace my ancient Clarke model) so I set about the frame and 'basket' with the knotted wire cup brush. Once I'd cleaned them up I set about painting them with POR15. Before painting you need to go over all the parts with 'Marine Clean' to degrease them. I did this in the garden to save getting the workshop too wet! The metal then needs to be coated in 'Metal Ready'. This seems to etch the metal and leaves it covered in zinc and makes it ready for paint. I then painted it with the POR15. This is nasty stuff and I always use gloves and very cheap B&Q brushes because you can't clean this stuff off!


The seat frame just needs another painting session and it's good to go. Unfortunately the 'basket' from the donor seat has come unwelded at one of the joins so this needs to be corrected before I can paint it. My plans for the future involve new straps, new foam and LEATHER! Watch this space!

Oil Seals and Engine Valances

I've been pretty busy at work recently and haven't actually had much time to do anything with the Spitfire. It's spent most of the year stuck in the garage waiting for me to sort out the oil seal problem that became apparent during the HCR!

I finally got around to draining the coolant and getting the timing cover off to see what the problem was last weekend. There wasn't anything too obviously wrong which was a bit annoying but the spring on the seal was a bit mangled and the timing cover was slightly bent. I flattened the cover and sanded it flat. I also stripped the paint of it and gave it a coat of VHT wrinkle paint. I fitted a new seal but I haven't got around to filling it back onto the car yet. With a bit of luck I should have a car that doesn't leak at much oil as a sinking supertanker.

I've also finally got around to finalising my engine valances. I put a lot of effort into making sure these fit perfectly and all that remains is to finish the edges, drill them for brackets and get them powdercoated. I'll try and get that done later in the week!

HCR '09

We did it! My brother and I actually completed the Historic Counties Run! As might have been obvious from my last post's lack of words, things got a bit hectic heading towards the weekend. There was a seemingly endless list of small jobs to be done. This list included replacing a leaky caliper seal, replacing the brake light switch, an oil change, replacing the entire clutch hydraulic system, replacing the throttle cable, adjusting the timing, removing the old starter solenoid, fitting the Nippon Denso starter, fitting 12v sports coil, replacing ballast wire, balancing carbs and refitting the parcel shelf!

I set out from Walsall on the Saturday, planning to meet my brother in Cambridge on the way. I put the hood down and got to Cambridge station about an hour and a half later! With my brother, Henry, on board we headed down to Southwold. It was at this point that that Henry pointed out that he'd never actually driven my car before, so we swapped seats and he got his first experience of classic motoring! We got to Southwold a couple of hours before the 'off' and had a fish and chips on the pier.

The first half of the run was relatively straightforward for us. The only minor hitches were our failure to brim the tanks and pump up the tyres so we had to stop off and do that. We also had a bit of scare when the temperature gauge went off the scale. The engine didn't look or feel hot and the 'tell tales' on the cylinder head and radiator were normal. When I noticed the fuel gauge was also a bit dodgy and the speedo illumination had failed I stopped worrying about it which was just as well because it fixed itself a few hours later!

The second half was more intense. Henry did the graveyard shift while I navigated. Thanks to a sat nav cock up we ended up wasting about half an hour in Hampshire and thanks to a cock up on my part we nearly ended up missing out Shropshire! For me, the Welsh roads were the best part of the whole event. We had a great time keeping up with Phil in the magenta GT6. Annoyingly though we'd developed an leak from the front oil seal which was dripping Duckhams finest all over the front pulley. Unfortunately the pulley was flicking it all over the drivers side brakes. I can now categorically confirm that oiled brakes don't work very well! Fortunately the were still just about good enough to finish the event on and we made it to Newport only a couple of hours late!

The trip back would've been a bit much with the dodgy brakes, so I had to call the AA in the end and we made the journey back on a flatbed. In all honesty I wasn't even sure it'd make the start line so I was absolutely chuffed that we finished the event. We had a great time, drove on some great roads, met some cool people and ended up completely knackered. Next time I'm going to book some time of work afterwards!

More pics on my facebook album here!