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What have you done today with your Austin Seven
The engine on my RP was rebuilt professionally only 1000 miles (but about ten years) ago. When I got it the car had covered only 300 miles or so since the rebuild. It developed a major oil leak which I tracked down to the Austin square headed 5/16 BSF special bolt that locates the camshaft bush. I lifted the block slightly so I could remove the bolt with a view to reinstalling it with some sealant. Having inspected it and observed the absence of much thread in the crankcase I shall remove the camshaft and redrill the bush and tap it to take a 5/16 cap head bolt which I'll seal with a Dowty washer..

I can see how the original installation when the engine was built at Austin's would work, with good threads in the crankcase and a tight hole in the bush to take the pin, there would be no movement at all. The little bit of wear that must have been present when the engine was rebuilt has allowed the camshaft's tendency to work forward to bear on the pin, which you can see is bent, and so erode the threads in the crankcase leading to my "gusher".

Interested to know how others address this problem.


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I'm surprised if the axial forces generated by the cam gear alone have bent the screw Colin. Are you sure someone hasn't tried to remove the shaft with the screw still in place?

It's important to limit end float here, and while the mod you describe should get you going again you need enough crankcase thread left to anchor the bush firmly in place. Before now I've drilled these holes oversize, plugged, re-drilled and tapped, creating a brand new thread (carefully positioned of course). If not too bad you may be able to open out a size larger instead. But this is a job difficult to do in situ I think.
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I don't know what others have done. I am assuming the pin has been bent by the movement of the camshaft since it seems unlikely that anyone rebuilding the engine would use a pin in this state and I don't think the previous owner ever had the engine apart after the rebuild. On my other car I had to replace a cam gear and in that case I tapped a new oversize thread through the crankcase and the bush with the engine in the car. It was fiddly but easy enough with a decent extension on the tap.
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Had there been a copper washer under the bolt head, it would provide a very crude backlash adjustment for the camshaft bearing - I did say crude !
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Well there was a fibre washer, which I think counts as even cruder!
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I think it unlikely that the pin would bend so badly simply from the cam gear loading Colin, far more likely that as Chris suggests it has received a good solid clout at some point. Tapping the cam bush and using a Dowty washer is without doubt an excellent solution, most bushes these days have some wear in the locating hole, any movement at this point will simply allow the cam to kick back and forward exaggerating the problem, causing further wear and leaks.
Black Art Enthusiast
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Here in the Colonies I had a similar situation with a 1930 American Austin motor that created a destructive problem at the dynamo. The cam bushing was able to move forward enough to destroy the fiber gear on the back of the dynamo. The repair consisted of centering the locating hole in the bushing with the hole in the crankcase. Use a long drill bit drill both the crankcase and partially into the bushing (block was not removed). Bushing was then removed to complete drilling the hole. Bushing was then put back into position  making certain the holes were lined up. Hole was then tapped for an Allen head bolt of the correct depth. The bushing needed to be removed again to get the new threads  to the bottom of the hole. Again the bushing was reinstalled, aligned and then the bolt was installed to complete the repair. Sealant was applied to the threads.  Repair has been working for the past 350 miles.
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What I did this evening couldn't be photographed as it was intentionally well after dark. Having fitted new reflectors in the two forward facing lights allowed  in the Measham regs, twenty miles or so of seeing what they are like. The weather gods could not have provided better test conditions, rain, sleet, some very thick mist  as well as glimpses of starlight. Great improvement. Now the driver will be able to more or less see what road we are proceeding along. Whether it is the intended route is another matter.
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As it's a bright dry day I went up to the garage and started Mathildeux up for the first time in a month. I do wish that the starting handle was still available to turn the engine over a few times but it started on the third pull of the rod. A quick 5 mile spin round the block (country lanes that is) until it was too cool to continue.
The Punch Bowl at Marton-cum-Grafton (see previous posts)

  https://www.austinsevenfriends.co.uk/for...l#pid38135

should be having their first Saturday of the month  classic gathering next Saturday so if the forecast for a dry and sunny/warm/overcast/not freezing week holds I'll be there.
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I must admit that since my trip to Santiago de Compostella in the RP it hasn't ventured out much. Neither have I, but that was mainly due to a spell in hospital and a period of convalescence. I have however been "busy" with other matters when able.

My daily runabout is a 1995 Citroen C15 van which I have owned for the past 10 years or so. The last "Contrôle Technique" raised a couple of issued that would need sorting for the next time, one of which was that the steering rack was badly worn and needed replacement. I had looked at the possibility of buying a refurbished rack but even so they weren't cheap (like me). The problem was solved one day earlier this year when for another reason I had to visit my local "garagiste" and I noticed another C15 in his yard. After asking what he was doing with it I learnt that is was scheduled to be scrapped because of various issues including a lack of documentation. I had a quick look at it and saw that the steering rack was good, with no wear. How much do you want for the van, I asked. Dunno, what're you offering? How about 100€ says I. OK no peroblem. I'll bring it round this afternoon - it turned out that the van was a runner, but the gearbox was "tired" as were the drive shafts, and some other bits.
Anyway, I got myself a complete 2004 C15 van for 100€ and the plan was to strip it for spares and scrap the shell. This is what I bought:

[Image: 20190729-144901.jpg]

That was back in early October and the van was driven into the garage and slowly stripped of its parts. About a week into the strip, a courier from UPS called with a parcel and enquired if I wanted to sell the seats. I didn't because they were better than I already had, but the engine and gearbox (minus starter motor and alternator) were there, for 100€. Done, says he. It's for my father in law. He came back a couple of days later and paid cash. Cushty. I now had a load of C15 spares for free!

After taking it all to bits, the front subframe and steering rack were reconditioned ready to fit into the other C15, but what to do with the rest. Flash of inspiration - I'll make a trailer out of the back half and dump the rest. Here it is:

[Image: 20191224-145457-resized.jpg]

So now I have a C22.5 = C15 plus C7.5... Smile Handy for all those jobs around the house:

[Image: 20191229-135614-resized.jpg]

Apologies to all those skilled metal bashers out there, but it works and all it cost me was 120€ for the tow hitch, jockey wheel, steelwork and paint. Don't you just love it when a plan comes together!

On other matters closer to the thread, I checked the oil in the Austin and it was fine. The horn still works too.
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