1986 Black Max 175 Bogs out

[hmatt1125]

I have 1986 black max that when I put the throttle down it doesn't want to go but will eventually get up and go. Takes about 20+ sec. I have replaced the starter boxes and noticed that there were a couple of wires that corroded from the idle stabilizer that I spliced and fixed (I assume). It helped with the idle which it should but I was wondering if there is a spark enhancer that is suppose to be there? The guy who owned it before me rebuilt the entire engine so he claims although I can say that he showed me the bills as evidence and he is a mechanic (30+ years). I didnt know if he might of left it off?? Any advice of why it might be bogging out? Thanks

 

[j_martin]

Re: 1986 Black Max 175 Bogs out

What the heck is a starter box? Is that near the mufler bearing?

There are many tune items that could be off. If it has good compression, then one or more of those items is the problem.

The sequence is
Check compression
Check carburetors (go through them, clean them up, and set any adjustments.)
Check fuel pump and fuel hoses, internal and external
Check for spark
Examine bleed hose routing and condition. Check bleed valves.
Do a formal link n sync, which is the linkage adjustment and timing procedure.

Then you can start troubleshooting, but you probably won't have to.

If you want to stab at it, bog is usually caused either by lean idle mixture, or premature throttle pickup.

hope it helps
John

 

[hmatt1125]

Re: 1986 Black Max 175 Bogs out

Thanks John

The starter boxes- best way to describe them would be similar to a distributor. 2 boxes back to back with wiring on each post.

I did some reading last night and was wondering with the making it richer or leaner would i have to get a different size of screw Main Jet/Idle Jet/Vent Jet;with a smaller or larger orifice?

It runs great when not in gear but when put in gear it struggles. I will check the carbs.

Thanks Again

 

[j_martin]

Re: 1986 Black Max 175 Bogs out

Thanks John

The starter boxes- best way to describe them would be similar to a distributor. 2 boxes back to back with wiring on each post.

I did some reading last night and was wondering with the making it richer or leaner would i have to get a different size of screw Main Jet/Idle Jet/Vent Jet;with a smaller or larger orifice?

It runs great when not in gear but when put in gear it struggles. I will check the carbs.

Thanks Again

If you want people to know what you're talking about, those parts are called switchboxes.

Your best bet would be to get serious and go through the sequence I described above.

Without compression, the motor is mechanically sick
With compression, there's a bunch of things that all have to happen right, and in the right sequence. Start with clean fuel and adequate spark, and go from there.

It takes 3 cylinders and about a gallon/hour of fuel to make it sound good on the muffs. It takes all 6 and 16 gallon/hour to actually run.

Carb jetting is fixed. Don't change them unless there's a reason, like high altitude operation, and then be sure it's factory specs.

hope it helps
John