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.
Hi Gareth, your right that it is not the standard BSP size, as everything (normally) over nominal 1" is 11TPI.
I presume the inclusive thread angle is 55 degrees?.
Is the Outlet a threaded insert, or part of a Casting?. I'm wondering if they machine cut the thread to a special size.
A picture would be good if you can provide one.
Hi Richard I'll dig a photo out when I'm next at the unit. It is part of the casting.
10 hours ago, expeatfarmer said:
Some of the threads on mG2 137 were like that , they turned out to be what are known as "cycle " threads from the bicycle manufacturing industry. Which would fit with 137 having a Sturmey Archer engine.
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.
3 hours ago, Wristpin said:
Very unlikely to be Cycle Thread in that diameter. No reference table for Cycle Thread goes any where near 2" .
My guess would be a manufacturer's special.
That's what I'm fearing, can't see why they would use a special thread.
12 hours ago, wurzel said:
is it female or male your after you may have to cut your own
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.
if you google 19tpi it comes up as 1/4 bsp its either a none standard thread or a different tpi count
cheers nick
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
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.
Hmm sounds like there's a few things it could be, I'm beginning to wonder if it would be easier just to drop in a replacement engine...
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.
Though the breaks are not working yet, I can fix these easily enough. One issue I have is I think the carb has seen better days, probably needs a new set of parts or replacing. It has been cleaned out thoroughly by my friend who restores classic cars, and the engine runs but it has a sweet spot at fairly high revs, and doesn't run well at all above or below. Also under load it splutters sometimes. But still, I am happy it runs and I will look forward to using it more
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.
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.
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.
Very nice, the finishing touch(es) !!
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.
Howard Gem G206, The earliest one left?
in Step by Step restoration
Posted
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.