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With the gearbox rebuilt, it was time to turn my attention to the thrust bearing etc. When new the instruction book said that the engine had to be split from the machine, clutch removed and the bearing greased every hundred hours or so. As you can imagine this didn't happen very often, infact Howard must of had so many complaints about this because after number G501 onwards they went to the trouble of redoing all the castings and moving it inside the box. The operating bars as can be seen were badly worn, again G367 donated better condition parts. As already mentioned somebody had cobbled together a thrust bearing and housing etc that had worn away part of the gearbox shaft. The drawing in the manual didn't show what the housing should look like or even what size the bearing should be so a new assembly was machined from scratch. This was fitted along with a brand new clutch plate as the old one was looking very second hand. The bearing was also packed with "Pecker Grease" to hopefully last a little longer between services. Next stage was to file down some over size key steel to take up a little bit of damage on the clutch locating keyways.

After stripping the box totally, every bearing was found to be shot. What then followed was a couple of weeks work of work as some of bearings were impossible to obtain. Bar one they were all imperial, but the odd one had an imperial centre and width, yet a metric outer?!? The only solution was to make a collar to go over the outside of an imperial one to turn it to metric. The main shaft was badly worn, caused mainly by a home made codged up thrust bearing that somebody had fitted at some point in its life. This is where G 367 proved invaluable as I was able to use the shat out of its gearbox. The bill for the bearings exceeded £300 on their own, if it had been metric it would of been so much cheaper. New seals were also fitted throughout, I had to adapt the housing where the clutch one went as there was nothing commercially available. Once reassembled I initially was panicking as the box was very tight and sounded like a bag a gravel had been thrown in it, this fortunately was rectified by fitting a shim under the main shaft bearing to position the crown wheel in the right place. I had never done a gear box properly before, I just hope it works ok once I fire the old girl up for the first time, otherwise it could be an expensive bang...

Photos of the strip down.

An initial assessment revealed that the machine was missing its magneto, silencer, chain cover, it also had the wrong wheels fitted. Luckily I also own the remains to G367,(pictured Below), another very early Gem but sadly this on is far to gone to ever restore, but ive been able to use it for some of the missing parts. After checking the factory records it was revealed that this example was built on 10/12/1941 and dispatched as part of a pair along with G207 to Trewartha Gregory & Dolge Ltd in Cornwall (they are still trading today) via LMS goods rail on the 15/12/1941.

As this project is nearing completion Ive decided its finally time to share it. This is one of the reasons why work on G621 has been very slow. Back in April I spotted this early Howard Gem on ebay, the photos below was all I had to go on. There was no serial number visable, but I was hopping I was right in thinking it was one of the short gearbox models (the first 400 made had a shorter gearbox and frame due to the clutch thrust bearing being on the outside rather than submerged in oil.) I made an offer as I felt the buy it now price was to high, and about 15 minutes later my bid was accepted. When it arrived back I found the serial number hidden under the rust and was pleasantly suprised to find it was G206, which makes it the 106th Gem ever produced (production started at G101). Ive been researching Gems for many years and prior to this the lowest number I had seen was G357, so at the present this is the earliest known Gem to exist. Realising how important this example is in the history of Gem's I decided to press on with the restoration. I will upload the photos as and when I have time over the next few days.

Hi Richard I'll dig a photo out when I'm next at the unit. It is part of the casting. Thanks for the suggestion, I've been able to identify all the other threads as either bsf or bsw, just drawn a blank with this one. That's what I'm fearing, can't see why they would use a special thread. It's a female thread that I need, I don't posses the skill to cut my own nut unfortunately.

Looks like a giant jigsaw puzzle, Paul. Hope you manage to find all the new parts off your source, otherwise hopefully the damaged cogs will be the same as something else more common. Are the bearings ok? I've just recently rebuilt a gem gearbox and because all the bearings were imperial the bill for them came to over £300 on their own.

This is the problem I'm up against. I've used a very accurate set of thread gauges to arrive at 19 threads per inch. Every chart I've used doesn't seem to make sense. Due to my job I have access to allmost any bsp fittings so it defiantly isnt it. Thank you for your thoughts. I would of thought that jap would of used something off the shelf but I'm dammed if I can work out what.

On a jap engine the exhaust outlet is threaded, it measures 2" or 50mm across the threads and has 19 threads per inch. Can anyone identify what it is please?

Due to a number of reasons including on going health issues I haven't done much to this project for a while, but last night I dropped the main frame off at my local boasters. Just depends how often he goes to the pub as to how long it takes him to do it. Will update the photos when it comes back.

Hi I'm looking for a silencer for a 600cc jap engine as fitted to a Howard gem, ideally the complete thing but just the down pipe and nut would do. Would even buy a complete engine.

I used to have the older version of this and it was useless, but to be fair it was purchased second hand. I can't rememember the make of its replacement at the moment but if you look on here you will see a topic on it. Way in front of the sealey in my opion Just looked it up it was an rtech.

Hi due to unforeseen circumstances my Volvo C70 soft top that's in my avatar is very reluctantly for sale. 95k with full Volvo ( bar one stamp) service history, recent cam belt, 10mths mot. 2.0 automatic. - recent expensive tyres as well. Car comes with full heated leather, electric everything and being Volvo it all works, air con, cruise etc. thought I'd mention it on here before letting the vultures on eBay pick over it. £2000. - an awful lot of car for the money.

The valves are very easy to do, there's guides on google and YouTube, I'd definatley do it as the next job. To be honest it's the first job I do on any small engine, cures about 90% of problems particularly ones that look like fuel as if the valves are pitted the engine can't suck the petrol in properly.

Probably a stupid question but have you reground the valves, particularly the exhaust? The symptoms you list would make me think it's this rather than the carb.

An ex girlfriend of mine took to making silent calls when we split up ( this was years ago), allways with a withheld number, I stopped it by holding the phone over a very large speaker turned up to full volume and pressing answer.

Just picked this up yesterday after a 4 train journey to Dorset. No fancy electronics here. Everything can be fixed in the drive way with a bent paper clip and a hammer. I used to have a couple back in the day when they were common, but now they are virtually extinct. Its the mythical one owner car with only 46k on the clock and 21 dealer stamps in the service book. 99% rust free, no rot at all, even the arches are sound. Almost unbelievable as its 22 years old! Just needs a very thourgh polish to bring the paint up nearly perfect, good on fuel for a 2 litre, I got about 38mpg on the way home which is a lot better than the 18mpg that the Volvo parked next to it does.

I'm very envious of all that space, but you know what would happen if I did, wouldn't be very long till it was full!

I'll be watching this one with interest after seeing your creation at tractor world. Looks a big challenge but well within your capabilities.

I'm not overly familiar with these but are the crankcase seals good? If not then it will not draw fuel properly.

I've seen worse, if you can easily find replacement parts then great I'd go that way, however if you can't, I'd get the valve seats recut and if they come up ok you should be able to have the outlet repaired.

Tonight I painted the wheels in etch primer. As tempting as it was to fill in all the flaws in the castings, I again left it as factory finish.

Here's a sneak peak at my 1946 series 1 gem that the other plate is for. It's hardly ever been used scince new, but was suffering the ravashes of time from living outside in a open ended shed that wasn't big enough to properly house it.

Single plates usually come out at £45-£50 each. Chris did me the 3 for £120. As overall the spend on this machine is on track to be quite low( just an awful lot of time needed) I felt it was worth while spending a bit on taking it back to as close to new as I can get, the originals as can be seen earlier on in this project were badly damaged. The second roteho plate is for another project that I hope to reveal at some point in the next few months.