Author Topic: HELP Royal Enfield 1960 Constellation wont start  (Read 485 times)

0 Members and 1 Guest are viewing this topic.

stewlane

  • Scooter
  • **
  • Posts: 12
  • Karma: 0
on: October 22, 2022, 12:41:33 pm
Hi all, just purchased a 1960 Constellation with Wassell electronic ignition and it won't start, please could someone give their thoughts or ideas

the following has been checked and is correct.

1. new gel battery, voltage 12.8
2. Fuel reaching both carbs and floods when button depressed and both carb operating freely with throttle.
3. new E5 unleaded fuel in tank
4. good strong blue spark from both spark plugs
5. polarity of Wassell stator cables correct.
6. no air filter fitted to Amal 376,s
7. good compression.

cheers n.g


Adrian II

  • Grand Gearhead
  • *****
  • Posts: 3,651
  • Karma: 1
  • Sharing my ignorance with anyone who needs it
Reply #1 on: October 22, 2022, 02:08:48 pm
Blocked pilot jets? I'm assuming whoever fitted the ignition timed it correctly and fitted the spark plug leads to the correct plugs!

A.
Grumpy Brit still seeking 500 AVL Bullet perfection! Will let you know if I get anywhere near...


AzCal Retred

  • Chennai Wrencher
  • Grand Gearhead
  • *****
  • Posts: 5,496
  • Karma: 0
  • a journey of a thousand li starts under one's feet
Reply #2 on: October 22, 2022, 06:30:58 pm
Didn't another gent here find that his camshafts had been installed incorrectly phased, which led to much tooth gnashing? If this is a "new to you" machine and you didn't personally do the assembly maybe worth a look...
A trifecta of Pre-Unit Bullets: a Red Deluxe 500, a Green Standard 500, and a Black ES 350.


stewlane

  • Scooter
  • **
  • Posts: 12
  • Karma: 0
Reply #3 on: October 22, 2022, 07:29:59 pm
Hello , the bike has a twin spark coil and fires the same time on both leads,

if the carburettor pilot jet was blocked wouldnt it start but not stay running?


Adrian II

  • Grand Gearhead
  • *****
  • Posts: 3,651
  • Karma: 1
  • Sharing my ignorance with anyone who needs it
Reply #4 on: October 22, 2022, 10:04:07 pm
So I'm guessing it's a "wasted spark" ignition. When you kick the engine over unsuccessfully a few times, is there any trace of fuel on the spark plugs when you take them out? Sounds like the fuel is going into the carb float chambers but not to the staring circuits. This assumes no air leaks where the carbs are bolted on.

A.
Grumpy Brit still seeking 500 AVL Bullet perfection! Will let you know if I get anywhere near...


AzCal Retred

  • Chennai Wrencher
  • Grand Gearhead
  • *****
  • Posts: 5,496
  • Karma: 0
  • a journey of a thousand li starts under one's feet
Reply #5 on: October 22, 2022, 10:05:56 pm
I assume you've never seen/heard this machine run?

The distributor is 1/2 crank speed, so the Wassel has to have two pick ups, unless it is driven off the crankshaft? In any event the timing needs to be verified.

Does it even try to run on starter fluid?

In any event it's a pushrod 4-stroke. If it has 90 PSI or more compression, spark at about the right time, it has to run on starter fluid. So either the cams are mis-installed or the spark timing is waaay off. Gap some new plugs to 0.015" - 0.020" and try on starter fluid.

If it isn't even trying to start, then it's time to put some numbers to the guesswork.

First - put some real numbers to the compression. Record cranking PSI on each cylinder with a wide open throttle. 90 PSI or more is good, maybe balanced within 5 PSI or so side to side is real good

Next - find a helper and a timing light, pop off the primary cover, mark TDC, and see where the spark is really happening. Anywhere near TDC and it should either backfire or try to run. If it's not, make it happen.

If it's all good and still nothing, find/make a degree wheel & attach to the rotor. Pull the rocker covers and "rough 'n ready" degree the cam if you don't have a dial gauge. Exhaust opens maybe 10 degrees before BDC, closes just after TDC. Intake will open just before TDC, likely close just after BDC. Record opening & closing degree numbers for both cylinders. Measure max valve lift as best you can, should be the same for both intakes and both exhausts, maybe 0.3" - 0.5" depending on the cams. Others here have actual numbers if you can find a dial gauge.

If the cam timing is at least close, spark timing is close, compression numbers are in the ballpark, it HAS to run on starting fluid. AFTER you hear it pop & run a bit, the then carb is the hold up. Get the jet/needle numbers from some else running that same carb, compare to your carbs jetting.


A trifecta of Pre-Unit Bullets: a Red Deluxe 500, a Green Standard 500, and a Black ES 350.


stewlane

  • Scooter
  • **
  • Posts: 12
  • Karma: 0
Reply #6 on: October 23, 2022, 05:30:53 pm
Thanks Adrian and Azcal , i will try your suggestions and keep you informed.


stewlane

  • Scooter
  • **
  • Posts: 12
  • Karma: 0
Reply #7 on: October 25, 2022, 09:06:22 pm
Looks like the timing is totally out!

Would someone  know in degrees what the fully advanced angle btdc would be for setting up the electronic wassell ignition?


Adrian II

  • Grand Gearhead
  • *****
  • Posts: 3,651
  • Karma: 1
  • Sharing my ignorance with anyone who needs it
Reply #8 on: October 25, 2022, 10:16:36 pm
I'm assuming the fully advanced figure should be the same for points + coil, magneto or electronic. The workshop manual gives a linear figure of between 3/8" and 7/16" BTDC fully advanced, or 1/32" BTDC fully retarded.

The 700 twins have the same bore and stroke as the 350 Bullet, timing in degrees for the Bullets is 32° BTDC fully advanced - probably a good place to start, and you can adjust to optimise.

Free manual to download here:

https://accessories.hitchcocksmotorcycles.com/Workshop-Manuals-To-Download

A.
Grumpy Brit still seeking 500 AVL Bullet perfection! Will let you know if I get anywhere near...


stewlane

  • Scooter
  • **
  • Posts: 12
  • Karma: 0
Reply #9 on: October 25, 2022, 10:25:35 pm
Thank you