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Discussion Starter · #1 ·
Hi to all

I just bought a 99 grand touring and It starts fine. after a couple of minutes it sounds like its not running on all 3 cylinders and under load it backfires through the exhaust. also the rave vale on the cylinder closest to clutch is leaking at gasket where it attaches to engine. any ideas on what could be the problem. and could the rave valve cause this problem? thanks
 

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I would start by unscrewing the plug wire ends from the plug wires and trim the end of the wires with side cutters. Do the same at the coil end of the wires. They unscrew from the coils. Trim the ends put a dab of dielectric grease on the ends and screw them back together. Buy all three rave valve gaskets. They are cheap. Pull rave's off clean the blades and reassemble. This is all cheap and easy maintenance work You're backfire is caused by you're dead hole firing intermittently and is very hard on the crank. It could also lead to a bent rod as the piston try's to compress raw fuel in the combustion chamber. That should fix you're issues. I would pull the carb rack off as well needles and seats are $45 per carb bowl gaskets are cheap. This gives you a chance to make sure its setup right . I go through carbs on anything i buy as well as part of routine maintenance. All this can be done in about 3 hours with minimal tools. If you take it in for work it will cost you a lot. If you need anymore help just ask . That's what the forum's are designed for.
 

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Discussion Starter · #4 ·
Rebuilt the rave valves, adjusted fuel air mixture screws back to factory settings. Noticed that the plugs are BR8ES and factory specs are BR9ES. also plug wires are new as well as plugs. have spark and fuel just not firing. could it be bad gas? Any imput at this point would be very helpful. Might have to wait until spring and do carb rebuild drain gas and start fresh. dont want to damage engine and really dont want to bring to shop.thanks
 

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As i said rebuild carbs. Drain all fuel pour in fresh. When you have the carbs off it would be in your best interest to check carb boots as well as reeds because you're already there. Carb boot gaskets are cheap too. use new ones dont use silicone. After using br9es to fine tune carbs i use iridium br9eix plugs they are easier on the coils and not so prone to fouling. Ofcourse if everything is set up to factory specs it should not be an issue to begin with.
 
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