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Help? 2 new issues - Carb sync, no consistent vacuum on one cylinder & a broken bolt!


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Hi Guy and Gal experts,

 

I had another frustrating day turning wrenches on my Arizona 1986 Venture Royale. AZZI is still fighting me compared to my other Venture's which have been happy to be fixed up and tuned. Anyway I have 2 questions/issues that I would like to get your advice on:

 

1. I attempted to sync the carbs today with my trusty Carbtune meter. I have synced my other Ventures many times and it is usually a piece of cake.....but AZZI threw me a curve ball as usual. The front left cylinder does not appear to have consistent vacuum, and that happens to be the cylinder that does not have an adjustment screw and is usually the baseline to align all the other cylinder to. For the life of me I can't seem to find a vacuum leak that would be an easy cause for this behaviour so I'm worried it is something bigger. All remaining cylinders show proper levels on the carbtune and adjust just fine with the adjustment screws. What the heck could be causing this????? Here is a youtube video showing what my carbtune meter is showing with the front left cylinder being the trouble maker. Any insight would be much appreciated!

 

 

2. While attempting to replace the leaking valve cover gaskets I got the very bad surprise that the previous owner had broken one of the valve cover bolts off and simply glued the head of the broken bolt into the rubber bushing that surrounds these bolts in the valve cover. Now I know why the valve cover gasket was leaking so bad on the rear cylinders!!!:doh: How the heck can I extract the broken piece since I can't access it while the motor is in the bike and I don't want to have to pull the motor if I can avoid it. Can I simple unbolt the bracket/cam retainer that the bolt is snapped off in so I can work on extracting the broken bolt at the bench, or would this cause me more problems by messing with that while it is in the bike with limited access and ability to torque it properly upon reinstallation? Sorry I don't have a picture of my broken bolt situation, but here is a pic of the head and the bearing bracket I'm thinking of removing so I can work on extracting the broken bolt without removing the engine. I'm really surprised that the PO could even snap a valve cover bolt as they actually have a thread limit to how far they can actually be turned in before they bottom out!

 

Screen Shot 2016-03-29 at 10.05.05 PM.pngScreen Shot 2016-03-29 at 10.19.27 PM.jpg

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Your left cylinder butterfly is open. Seen this happen lots of times. You need to start from scratch making sure that the butterfly is fully closed to start with.

The bolt is not torqued into the bearing cap so maybe easily removed with a pick,,, maybe,,,, try it. Seeing as the bolt shoulder seats there should be no pressure on the threads. If not, take out the cap, remove the bolt, and re-install. Torque as close as you can to specs.

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your no vacuum could be cause by a clogged vacuum passage. You might try to shotgun the carb with some carb cleaner. Here is a link to a PDF that talks about doing it on a Vmax which of course will work on our bikes also.

http://v4musclebike.com/forums/showthread.php?t=7696

I have done it to mine with a vacuum issue and is does work.

Good luck.

Rick F.

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On the sync, the reason you have low vacuum on #2 is because you started with the idle adjustment too high and ended up bringing the idle down by choking the other cylinders. #2's adjustment is the one you start with, then you adjust the others to it. At where you are at, what I would do is lower the idle on the wheel under the bracket. If you do it slightly you should be able to keep it running with less vacuum showing on #2, which will bring the gage up and then start adjusting the others again, as their throttle plates will be closed too much, causing their gage readings to be even higher.. If my memory serves me correctly, once you start getting the #2 better, you will have to go to #1 and move it until it brings the idle up some. Once you get #2 and #1 reading close, then work on the others.

Randy

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I agree with Randy

 

Back off on ONE. That should start to create a balance on the left side (1&2)

 

Then back off on FOUR. That should start to create a balance from the RIGHT side to the LEFT side. At this point you can simply proceed with the normal sync sequence.

 

1 to 2 then 3 to 4 then 4 to 2. Just remember Back to Front (both sides) then Right front to Left

 

 

On the sync, the reason you have low vacuum on #2 is because you started with the idle adjustment too high and ended up bringing the idle down by choking the other cylinders. #2's adjustment is the one you start with, then you adjust the others to it. At where you are at, what I would do is lower the idle on the wheel under the bracket. If you do it slightly you should be able to keep it running with less vacuum showing on #2, which will bring the gage up and then start adjusting the others again, as their throttle plates will be closed too much, causing their gage readings to be even higher.. If my memory serves me correctly, once you start getting the #2 better, you will have to go to #1 and move it until it brings the idle up some. Once you get #2 and #1 reading close, then work on the others.

Randy

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I would first try to turn the broken screw out with a pick or anything else you can get on it. Many people have been able to tease the broken bolt out of there.

If that does not work, then since the cap you are showing is the outside cap, I would first rotate the engine so the cam lobes are pointed up. This way there is no valve spring pressure trying to bend the camshaft or mess with your torque settings. You should be able to get to those bolts with a torque wrench.

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