rounce Posted September 18, 2012 Share #1 Posted September 18, 2012 I bought an 87 venture royale this spring that has been stored for two years. The owner said that the carbs were redone before it was put away.( Cost him 750$ .. I didn't see the bill) Anyway, I brought it home and have been playing with it ever since. There was fuel problems and I finally got the bike running. I put in seafoam, and naphtha and it starts up and runs not too bad.. but I think it is not firing on all cylinders. I hooked up my carbtune and I get no response from cylinder # 1 left rear . No vacuum at all. When started it up this morning, I checked the exhausts and the left rear got hot very quickly and the other three got slightly warm in the time I ran it. I checked for vacuum after changing the lines to the carbtune with the same result as before. I have just pulled the plug and it was slightly damp and somewhat black. This is where I am at now. What should I do now? Any specific tests , and order to help trace down the problem(s)? Help! Link to comment Share on other sites More sharing options...
bongobobny Posted September 18, 2012 Share #2 Posted September 18, 2012 OK slightlyu damp suggests fuel is getting there but no ignition. This can be a multitude of things from corroded connection, bad coil or coil wire, or plugs. I would inspect both ends of the coil wires for any signs of corrosion as well as the coil ends. Put brand new plugs in as these engines can eat plugs. You may want to consider new wires especially if they are the original 25 year old ones! I would also recommend a compression test to see the condition of the rings and valves. Even though the carbs werre supposedly rebuilt, setting around for a couple of years ie enough to foul them up again. Also rebuilt does not necessarily mean rebuilt right!! Were they reassembled correctly, were they tuned?? All these things can come into play. You mentioned fuel problems, what kind of fuel problems?? You may need a new fuel filter, a tank flush, drain the carbs, etc... Link to comment Share on other sites More sharing options...
dingy Posted September 19, 2012 Share #3 Posted September 19, 2012 I hooked up my carbtune and I get no response from cylinder # 1 left rear . No vacuum at all. Call me crazy (don't think your hitting virgin territory though) but I would think you should get a vacuum reading even if the cylinder isn't firing. The cylinder should still pull a vacuum when the intake valve opens and the piston travels downward. It wouldn't show a vacuum if there were a leak at the intake manifold to head, the lower carb to intake manifold boot, head gasket compromised, or a valve not operating. The valve not working could be either valve. Exhaust valve could not be closing, or intake may not be opening. Or even with a cylinder rupture, but that would be readily apparent. Gary Link to comment Share on other sites More sharing options...
rounce Posted September 19, 2012 Author Share #4 Posted September 19, 2012 Call me crazy... I was checking the cylinder that I thought was dead and it showed compression. I then looked at the front left cylinder and the plug was not connected! I then looked on the right side and the front plug was not connected as well! The right rear was connected. All the plugs were changed out , wires recut at the plugs . It started well, but the # 1 cylinder got hotter and that cylinder still showed no vacuum unless the motor was revved up a bit. Is it still a carb problem, a valve problem or? Link to comment Share on other sites More sharing options...
friesman Posted September 19, 2012 Share #5 Posted September 19, 2012 Have you double checked all the vacuum lines? Mybe you have an open line sucking air that wont let the vacuum build up. My 85 had a leak this spring and it ran like crap when I found a plastic t-connector broken apart allowing it to suck a ton of air. Brian Link to comment Share on other sites More sharing options...
tz89 Posted September 19, 2012 Share #6 Posted September 19, 2012 Maybe a homemade stethoscope might help. Get some tubing and listen for air leaks. Link to comment Share on other sites More sharing options...
Mel Posted September 19, 2012 Share #7 Posted September 19, 2012 Not sure on these carburetors, but on others I've worked on, the idle adjustment is seperate from high speed adjustment. If the idle adjustment is way off on one carb, or there is some kind of internal problem, you may not get a vacuum reading at idle, only at a faster speed as the slide opens up. If all four spark plugs are now connected and firing properly, it may run pretty good at speed, but need the carbs adjusted at idle to get them balanced. Seafoam, Seafoam, Seafoam, and a good tune-up. Hard to tell after it sat for two years. Link to comment Share on other sites More sharing options...
bongobobny Posted September 19, 2012 Share #8 Posted September 19, 2012 Nah! You have a major leak on your carb throat or the base manifold. Those manifold tubes can develop cracks, the gaskets under them can develop leaks, and the head surface develops all sorts of corrosion. Found this out when I replaced all 4 of my intake necks... Link to comment Share on other sites More sharing options...
Venturous Randy Posted September 19, 2012 Share #9 Posted September 19, 2012 When you are doing a compression check, are you opening the throttle to let air in? To me, you should also open the slides, as that would also imped proper air flow to get a proper compression reading. If you had an intake valve stuck and not closing, you would have constant back firing through that carb if the spark plug was firing. RandyA Link to comment Share on other sites More sharing options...
rounce Posted September 20, 2012 Author Share #10 Posted September 20, 2012 Hold the phone! I went back to square one. The # 1 cylinder that I thought was suspect was getting warm, an the exhaust hot while the other three was not getting hot. So, I checked the other cylinders for spark with another spark plug and the spark was very good. I did this in turn separately with the same result. But there was no change in the way the way the engine ran. AHA! I pulled the spark wire on the #1 cylinder and the bike would not run. I then replaced the wire, and pulled the other three and the bike ran with little or no difference. Conlusion?The suspected # 1 cylinder was running and the other three were not . Now what? Its been an education! Please chime in! Link to comment Share on other sites More sharing options...
Bob Myers Posted September 20, 2012 Share #11 Posted September 20, 2012 a good carb synch would be a great place to start. If it comes"on" when revved a little then at least one is set way low. Possibly POP thought he was cranking the idle up and turned the screw used to synch that carb to the one beside it. Easily done, don't question my source on this knowledge. Link to comment Share on other sites More sharing options...
friesman Posted September 20, 2012 Share #12 Posted September 20, 2012 when ya get it figured out and ya need a carbtune youre welcome to borrow mine. I am in the south end of Regina right by Southland mall. Brian Link to comment Share on other sites More sharing options...
az1103 Posted September 21, 2012 Share #13 Posted September 21, 2012 Stored for two years is the key......Rebuild those carbs and you won't recognize the bike. Link to comment Share on other sites More sharing options...
rounce Posted September 27, 2012 Author Share #14 Posted September 27, 2012 Thanks for the help and suggestions. I haven't pulled the carburetors yet but it is on the agenda before snow flies. I'll keep you posted. I did put in a new fuel filter.... what a chore , mostly of my own making. I think it runs a bit better... Once again, thanks! Link to comment Share on other sites More sharing options...
MiCarl Posted September 27, 2012 Share #15 Posted September 27, 2012 Way out of sync will cause this problem. #1 is way open and the others are closed so not running. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now