Blackmax 150 won't start.

[Ryanrcer87]

I have tried literally everything I can think of. I usually don't have any issues beyond cleaning the carbs etc but this one is stumping me. I have good spark on all cylinders, compression is 115-120 on all cylinders, carbs cleaned with new gaskets, new fuel lines, new plugs, and fresh gas. Motor will crank if I open carbs and spray a little bit of carb cleaner in them, it will then run just fine I can shut it off and crank it up as normal with no problems. I let it sit overnight with the motor down and try to crank it and the same problem all over again. It turns over an over an over and never fires off, I put a little carb cleaner in and bam no problems the rest of the day. I DONT GET IT!


I have also checked the enrichment valve/choke operation and verified it is letting fuel into the carbs when you push ignition switch in to prime.

any help is greatly appreciated!

 

[racerone]

Advancing throttle for cold start ?---- Pushing the key in while cranking ?

 

[Ryanrcer87]

Yes sir I just don't understand it. I have never had an engine act like this.

 

[redneck joe]

I had a 91 Force that was like that, never did figure it out.

 

[Chris1956]

That sounds just like your enrichener isn't working. You checked to see the fuel run into the lower carbs?

If so, maybe the motor is cranking too slow? Clean up the battery cables, and check 'em for corrosion under the insulation.

 

[Ryanrcer87]

The enrichener is letting fuel through when I push the key in however it does not pour out?? I was thinking since it is gravity fed it would be only a trickle. Thoughts?

 

[Chris1956]

Gee, a trickle will still get the job done, I would think.

 

[444]

Have you done a link and sync? In neutral with the throttle fully up while cranking, IIRC on my 1978 175hp the carbs don't open and engine speed is controlled by the timing advance lever. I wonder if yours is not linked properly with the throttle controls?

 

[Ryanrcer87]

Interesting! How to I make sure it is synced correctly? I have tried cranking with throttle forward with no luck. But my carbs were open when I did this.

i would be interested in learning more about this. I can't figure this thing out and it is starting to weigh on me!

 

[444]

The process is in your service manual and needs to be done any time a carb is removed. It's a step by step process to dial in all the linkages so all 3 carbs and the timing advance lever are properly synchronized. After a few wasted trips to the lake trying to get my 175 to run right I learned not to bother hooking the trailer without having done a link and sync if I have pulled a carb.

 

[Ryanrcer87]

Does anyone have a copy of the service manual for a 82 Blackmax 150?

 

[Chris1956]

You should be able to find one online. Try the boatinfo web site. All ADI V6 motors should be pretty much the same for lnk and synch specs.