Forgot to add,
Seafoam and like cleaners work pretty good, you can just poor it down the carb at high idle or feed it through a vacuum line. A good quality fuel clean would help also. Don't expect a total tune up from a can, you are still going to to put in some time there!
Hows the oil look? Does your engine have a oil filter? Don't go adding oil cleaners unless you are willing to pull the pan, you can make it worse with cleaners since most don't have a filter. The crap all settles at the bottom of the pan, unless you dig it out, the cleaners just loosen and circulate it back through. Fuel is kinda of the same way, be prepared to change filters often if using a fuel system cleaner. Fuel differs from oil as you have the ability to catch the impurities in a filter.
I have seen the top end engine cleaners where you dump them end and shut off the engine. It coats and cleans while setting. Then you go run it fairly hard to blow it out. A high idle and a cup of water works really good an heavy carbon build up. Slowly poor it in while running at high idle. The water turns to steam and washes the carbon out, don't drown it or you can have a tough time restarting. It will let you know how much to poor in. You can also use a vacuum hose to feed water in, meter it down and go for a long heavy footed drive. Pull a long hill in a higher gear to really work the engine while feeding in water, the higher heat will steam clean the tops of the pistons.
Joe
