Hey group, got one for your eyes and ears. When my 87 is hot, it does not idle correctly-idle is set around 1100rpm normally-if i crank the idle screw in a half or more turns it will idle but then the revs will go up to around 3200 and stay there (no it won't 'pull down' using it in gear like a lean condition). I've played with the choke under these circumstances to see if there was any change in operation, but no. It starts well, and idles with the choke fine after a few moments. Sync is good, carbs/pilots clean. I have noticed a bit of wetness around the #1 &#4 throttle shaft seal (cannot see #2 0r #3). They do not appear to pull air in around them (used butane)... Ideas?

 

If I got this correct, at 1,100 RPM, the engine won't idle correctly. It tries to die, or goes up or down in RPM, or is just rough. But if you turn the idle speed up with the idle screw on the left, it idles correctly but is too high (3,200). Is that the problem?

If so, the first thing I would check is the pilot screws on all four carbs. I would bottom each screw lightly and back out 2 turns. You need a very, very long, thin screwdriver to get to carbs 2 and 3 pilot screws. If that doesn't do it, you will have to get into the float chambers and check the float levels (9mm). Then take out each slow jet and spray carb cleaner through it. The spray should come out the other end of the jet just like it goes in. If it dribbles out, the jet is clogged.

The manual says that a vacuum leak will also affect idle, as will a plug misfiring, the choke stuck on, dirty fuel filter, synch, and a fuel tank breather tube clogged.

 

How exactly do you set the float level and where are you measuring the 9mm?

 

Carbs were just gone through thats why I was betting against pilots/ vacuum issues. I'll pull them again (damn I'm getting good at this!) and check again.

 

WD-40 will do the same thing. A little more messy.