carb sync question

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Plastermaster
Posts: 2762
Joined: Sun Sep 30, 2001 12:01 am

carb sync question

Post by Plastermaster »

When I last installed my carbs after doing some maintenance on them, I made sure they were in sync. What I noticed as unnusual was that even though they were all within 1 increment on the synchometer, #4 sounds different. It makes a CH,CH,CH sound like when a kid imitates a steam train. Not the rithym but just the CH or SH sound. Its runs great, and both sides of the engine are within 10 deg CHT. Air bleed screw is closed as is vacume port. I checked compression about a week ago on 2 and 4 (1&3 are a pain to reach with the guage) and both were 163-165. Any ideas? I am wondering if a valve is not closing all the way. That would suprise me though as I checked the valves a couple weeks ago, and they have not budged in 7K miles.

BTW the engine has 1 year on it now and has been running flawlessly except for fuel related problems, but that is just that. The carbs and tank have been frustrating, but when the problems are worked out you really get to experience the perfection of this power plant. Race ballance isnt really apreciated if 1 cylinder is off a little due to carburation. When the intake is ballanced I get the experience of how flawless the long block is. The engine itself has been a blast. Like they say, "Pay now and cry once" Actually I didn't even cry once. Ive been smiling ever since I sent Jake back his proposal 17 months ago.

Any idea on the choo choo sound?

Thanks,
Ron