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Cali 850 1973 mistery

cse

cse

Tuned and Synch'ed
Joined
Oct 11, 2010
Messages
34
Location
Portugal
Hello,

This very pretty signora that has just been restaured by it´s proud owner developed a strange problem that has been driving us crazy these past few weeks.
After the restoration the bike started great, worked very well for 2 or 3 rides (about 150Km's) but then it just started to choke and barely made it home.
The bike had a non functioning left cilinder but it idled and the engine had dificullty in revving.
After 1 week of testing, dissassembling cleaning, reassembling carburetors and wiring we found out that there was a bad connection on the turn signals that were connected to the auxiliary headlights wires and the relay was stuck. Fixed it but still not work well. Finally we changed the condenser at it started working well...
The next day it was not working again.
This time the right cilinder was choked, it didn't even idle and the right sparkplug was wet.
Dissassembled the tank and etc.. again and after a thorough inspection we noticed that the choke cable from the right cilinder was stuck out of the distributing box.
Got it right and started working fine, tested it a few times and all seemed fine...
Next day it didn't work well again.
The left cilinder is off and spark plug is dry, the right cilinder works normal, and the engine holds the idle speed but the left cilinder doesn't even get warm.
Only strange simptom is that for what I know the engine should work without the condender but it doesn't, soon as you unplug it the engine dies and won't start.
The points are in the correct clearance and have been tested with another one. Tried 3 diferent condensers, checked carburetor cables and fuel lines, checked wires but can't seem to find the problem.

Luckily the weather has been terrible..

Please reply with known issues to the 1973 850gt california model IMG 2263
 
Had similar running issue with a 72 Eldorado. Problem with carb floats, float needles and seats. Plus the petcocks were messing up. Sometimes fuel would flow, other times it wouldn't. Once petcocks were replaced, floats corrected, and float needle seats were faced all the issues went away. If one spark plug is firing the other should. Look inside the distributor cap for any lines. Those lines may allow the high voltage for the spark plug to go to ground instead of the spark plug. Electricity will take the path of least resistance. BTW, nice looking Eldorado (or European 850 GT). The twin leading front brakes must be nice to have.
 
After many tries we spotted a bad sparkplug on the left cilinder, the spark was not always strong. Changed it for an old one and she works fine.
Must replace the cable plugs that go into the distributor and new sparkplugs again...
Try to post some more photos of the bike.
Thanks.
 
cse said:
After many tries we spotted a bad sparkplug on the left cilinder, the spark was not always strong. Changed it for an old one and she works fine.
Must replace the cable plugs that go into the distributor and new sparkplugs again...
Try to post some more photos of the bike.
Thanks.
Click to expand...


Be sure to use copper/metal wire strand wires. The resistor wires don't seem to work well on an older Guzzi. Old technology seems to work best on these bikes. Also the NGK 90 degree caps work well at the spark plugs.
 
Second what John said - on any guzzi this age I automatically replace the high tension leads and caps with solid wire and NGK caps. The original metal bosch caps are a short waiting to happen and the NGK caps are cheap.

Be aware that the NGK plugs have a changeable resistor (normally 5K). If the resistor is fitted use NON resistor plugs - NGK which I recommend have the R as a suffix. I never fit champions as they are often junk right out of the box - everyone else pretty much seems capable of making decent plugs.

If you don't use a resistor in the caps then use resistor plugs. I mount the condensers per Peter Roper's suggestion on the outside of the distributor cap - they get less hot that way and are easier to swap out. Check for a big blue spark both sides and then start working on the carbs per John's suggestions. Be also careful that the choke cable has some slack in it.
 
One thing about Chris R comment on plugs. I've never had an issue using the resistor caps with resistor plugs. Every bike I've touched seems to do well with both caps and plugs being resistor type. So long as you have a good coil, it shouldn't be an issue.
 
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