Unrestored 102 SD (Naval?)

[Beagle2]

Sorry to resurrect this prehistoric thread but I've finally found the time to (almost) get the SD working

My main difficulty was setting the ignition timing as there was no dimple or timing mark.

I calculated at the piston position for the spark and used a depth gauge in the bore to set the points. Not quite as accurate as I hoped and took some trial and error to get her started.

The engine will fire up nicely but then cuts out after a second or so.

I'm using the starting technique on the main site FAQ

I have managed to get continuous running but only if I start with a very small throttle opening. If I open throttle it cuts out. Sounded ok when running though.

• There is a good spark
  
  Fuel is fresh and at 10:1 ratio
  
  Carb leaks a bit but seems ok
  
  Fuel lines all clean
  
  Cap screw open
  
  Good compression (similar to other Seagulls I've owned)
  
  Correct height in test wheelie bin

Any ideas why it only runs for a second anyone?

I think I'll try different ignition settings next weekend.

I've set the plug and points to 20 thou. Do these older engines need something different?

[Stelios_Rjk]

Oyster's picture shows the correct position of the back plate.



You could also check the jets, maybe there is one blocked.

Some experiments on the points gap may reveal something. Try gradually changes from 10 to 30 thou.

[JERSEYMAN]

Sounds like a carb issue

[kevinemery]

I was sorting through a box of bits at the weekend and found an identical throttle lever, was not sure where it came from or if it was from a Seagull.
Let me know if you need one.

Kevin

[Beagle2]

Thanks for your quick responces guys. Good to be back Seagulling

I'll have a look at the jets at the weekend. Fingers crossed!

@Kevin, thanks for the offer but I already have the correct brass one


Cheers

[kevinemery]

No problem, looks like its already found a home.

[kevinemery]

Just remembered, I had trouble about 3 years ago getting a 102 running and bought the service manual from John.
It tells you how to set up the carb, had it up and running in no time.
Regards
Kevin

[Collector Inspector]

Seems to be sorted aye?

B

[Beagle2]

Hello, I took the carb off last night, you could see light through both jets. However I passed a thin brissel through each for good measure. I think you can now see more light through them, although it may be optismitic imagination.

I forgot to add, the float chamber is continually overflowing. Would this affect running or just waste fuel?

The float is fine and the needle seems to seal ok. Obvoiusly something isn't right though. I'll try reseating the end of the float needle using grinding paste and possibly cutting a lower indent for the float stop. Hopefully this should help a bit.

All jobs for the weekend. I'll let you know how it goes

Thanks

[Stelios_Rjk]

When I clean jets I usually dip them in a solvent such as acetone overnight. The next day with napkins or soft copper wire in case there are still deposits. I then dry them and usually I can clearly see the holes. If not I repeat. Compressed air also helps to dry them or to remove deposits.

The continues leak from the bowl is a matter. The float stands in a wrong position on the needle? Bent needle? Goo in the float bowl? Stuck button? A hole and some fuel inside the float?
All these things could be reasons for trouble.

I have also seen that the wire used on electrics that consists of many thin copper wires acts as a brush for the internal of the jets.


I hope this helps.




Cheers,
S

[phil]

If the float chamber is overflowing, something is preventing the float needle from closing properly. Most common bad seat or leaking float. Making another groove on the needle does not sound like a good plan.

[Oyster 49]

If the float bowl is overflowing then the needle is not shutting off the fuel supply. So either the needle valve is leaking, and/or the float is sticking down. I've had both of those on my SD. Check that the needle is true, and make sure the float actually floats! Also make sure the float bowl is as upright as possible.

Don't alter the height of the float, all that will do is change the fuel level and either cause richness or underfueling.

[Beagle2]

Hello, I've stripped the carb fully now.

The float body was fairly clean and the float passed all tests.

I noticed the needle has two indents to set the float height. Is this normal? And which one should I use for the SD?

The sealing end and seat area look fine.

[JERSEYMAN]

I am not sure if its the photo but the seating end of the needle looks shot, it has to be perfect if it's to seat

[Beagle2]

Here's a slightly better pic.

It seems blemish free.

Any idea on which grove to use for the float?