Autumn Rebuild

[pidjones]

The fuel passage seals are not o-rings. They are tall "U" in cross-section. You can find them here: https://newmotorcycleparts.net/fuel_sys ... parts.html
And, I think Randakks carries them, but in Viton (which for this application I would not recommend).

[heli_madken]

Thank you, the carb that was leaking interestingly did have an o-ring.

The nearest size u-ring I can find on the site is URING-4645 which is 6.5mm x 9.5m x 3mm? the seat is approx 10mm in diameter so it should work

The problem now is I am in the UK and cant currently find a supplier over here

[heli_madken]

No luck finding a supplier over here, do you think I could get away with making them out of suitably sized nitrile rubber hose? anyone done this?

[robin1731]

I've done numerous carbs. Used lots of viton rubber. Never had an issue. Even when taken apart after a couple years the rubber was still intact and pliable. Not sure why some keep knocking a known good product.

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[pidjones]

I've done numerous carbs. Used lots of viton rubber. Never had an issue. Even when taken apart after a couple years the rubber was still intact and pliable. Not sure why some keep knocking a known good product.

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Live with it in industry for 40 years. You learn it has places to use (heat, ozone, radiation) and places to avoid use (places that require resilience). I'm sure that I haven't done as many carbs as you, but I have used o-rings my entire professional career for seals that were permitted zero leakage.

[heli_madken]

Randakk's and Viton are out of the question for me, cheapest shipping is $123.33. I am surprised this hasn't come up before, are there any realistic alternatives, if newmotorcycleparts.net wont ship to me I am in trouble

[pidjones]

Randakk's and Viton are out of the question for me, cheapest shipping is $123.33. I am surprised this hasn't come up before, are there any realistic alternatives, if newmotorcycleparts.net wont ship to me I am in trouble

I've read of folks very carefully cutting replacements from tubing. I would very thoroughly leak test the rack (I use isopropyl to avoid gasoline spills indoors) before mounting it back on the bike. Careful checking with mirror and light through the screens for leakage should help.

[ericheath]

Apologies to the purists and real mechanics. In the “Not Recommended Best Practice” category I used two Harbor Freight nitrile orings sandwiched together to provide the thickness needed to seal two of the mentioned ports. Four years later, no leaks.

Your question about cutting your own has merits, but as above, is not recommended. I would even go as far to say you could get some orings of the same thickness but larger diameter and cut them down and superglue them to fit, but I am not sure how whatever glue you used would hold up to constant exposure to gasoline.

Whatever you do, save yourself the headache of removing the carbs repeatedly by using an alternative tank of a litre of fuel hanging six feet above the rack on a bench or somewhere you can view them for leaks.

[heli_madken]

Thank you EricHeath, I dont think I have any choice but to come up with an alternative, newmotorcycleparts.net have taken my money but are not answering my emails or providing any shipping information, the other suppliers I have found are all state side and ridiculously expensive on shipping.

I did get hold of some imperial size o-rings that are just short of 3 mm thick and stand proud of the seat, cant really see why they would not work other than the fact that as the carbs only have two bolting positions the clamping force isnt tremendously great in the seal area.

Like you say I will do some testing to make sure they are effective and give them a go, I have a couple of weeks before I actually mount the carbs to the bike so I will see if anything else turns up

[robin1731]

Thank you EricHeath, I dont think I have any choice but to come up with an alternative, newmotorcycleparts.net have taken my money but are not answering my emails or providing any shipping information, the other suppliers I have found are all state side and ridiculously expensive on shipping.

I did get hold of some imperial size o-rings that are just short of 3 mm thick and stand proud of the seat, cant really see why they would not work other than the fact that as the carbs only have two bolting positions the clamping force isnt tremendously great in the seal area.

Like you say I will do some testing to make sure they are effective and give them a go, I have a couple of weeks before I actually mount the carbs to the bike so I will see if anything else turns up

I sent you a pm. Look at it.

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[heli_madken]

Thanks Robin, I got sorted in the end via Randakks, when I actually placed the order postage dropped to just $15 so all good. I have to say excellent service from Randakks the seals arrived in the UK only a week after placing the order.

Everything is starting to come together now and I am hoping to get the engine back in the frame today!!

Went with the Viton version in the end -

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Nice new plenum seal -

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For some reason the PO took away the complete kick start mechanism, got some second hand parts and replaced. I played with this for about 5 minutes when I got the rear case on, small things as they say -

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Front and rear cases all back together and nice and shiny -

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Starter motor in position, I managed to get some of the shape back into the left front top engine mount which if you recall was just gobbed together with weld -

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[Fred Camper]

Looking like very nice progress. You now have to look for the weld on the motor mount. Nothing wrong with that. That seems to be one thing that happens when they fall on engine guards.

[pidjones]

Very, very nice. I did a crappy aluminum block held with screws to replace a rear one on mine. Luckily, neither are really something that stands out when the engine is mounted.

[heli_madken]

Thanks everyone, I have the engine back in the frame and cylinder heads in place all torqued up. I have the left (viewed when sitting on the bike) cam belt fitted, T1 timing mark used and reference mark on the cam pulley all lined up.

I am a little confused about fitting the right hand belt, according to the Wingovations instructions here http://wingovations.com/fitting-timing-belts/4591392336 the last statement says 'Turn engine to T2 and repeat for the right hand belt.' but none of the other instructions I have found mentions this.

Bearing in mind this engine has been out of the frame and turned over by hand without the heads on, what do I do set it T1 or T2?

[robin1731]

Go back and reread that article. When he says turn to T2 he is talking about setting the tension on the belts. Both belts should be installed with the crank at T1.

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