88 150hp black max hard to start

[duhn]

I have a hard time starting it when it is cold. Sometimes I can run the battery down before it starts.

I have checked the enrichener and it clicks. I pumped the bulb and then removed the bottom hose and pushed in the key and fuel would spurt out with every click. Is it supposed to spurt or be a constant flow?

Another question I have is, with everything all hooked up, are you supposed to see the fuel going into the carbs when the key is pushed in? or is such a small amount that it can't be seen?

Thanks

 

[Barnacle_Bill]

Re: 88 150hp black max hard to start

Those older Mercs are notorius for that. Turn the key on then push it in and hold it while counting to 10 slowly. Then start normally.

 

[j_martin]

Re: 88 150hp black max hard to start

I've found on mine that you need to hold the enricher for about 10 seconds, which will dump most of the fuel from the top carb bowl into the throat of the bottom 2. Then, while holding the enricher in, crank it.

When you figure out the right combination for your engine, it should start within 2 seconds.

1. If you're wearing down your battery, you're also hurting the starter motor. It's strictly a short run motor, and overheats quickly.

2. If it doesn't start within 10 seconds, quit cranking, reprime, and rethink your approach.

3. Starting technique is heavily dependent on weather. It can vary a lot.

Hope it helps
John

 

[duhn]

Re: 88 150hp black max hard to start

Thanks for the info.

My question still has not been answered yet. When the key is pushed in, is it supposed to be a constant flow? or is it supposed to be a spurt of fuel everytime the enrichener clicks? I can push the key in and hold it for as long as I want and it will only give it just a shot of fuel when it clicks.

I am assuming that there is supposed to be a constant flow with the key pushed in. Both responses tell me to hold the key in for 10 seconds. If there isn't a constant flow, is the enrichener valve bad?

Thanks
Devin

 

[hkeiner]

Re: 88 150hp black max hard to start

The fuel flows from the enrichener continuously while the key is pushed in. However, the total amount that flows is limited to what is in the top carb, and that is dependent on squeezing the bulb until firm before activating the enrichener.


The below info may help you confirm the proper operation of the enrichener.

 

[j_martin]

Re: 88 150hp black max hard to start

To clarify

The enricher just connects a small line from the bottom of the top carb's float bowl to inlet ports, also small, right behind the throttle plates on the carbs.

If the engine is sitting still, it dribbles fuel from the top carb float bowl into the bottom two intakes, just behind the throttle plate.

If the engine is cranking, or running, intake vacuum will pull fuel into all 3 carbs behind the throttle plates, and the fuel pump will keep the top float chamber full.

That's why you have to hold it awhile before you start, to get enough prime into the manifold to make a difference, and also hold it while you're cranking, to further enrich it, and begin enrichening the top 2 cylinders.

It's a pretty crude system, sorta like starting up a 1950's tractor, but it works.

hope it helps
John

 

[BQUICK]

Re: 88 150hp black max hard to start

How do you adjust it? My 84 Black Max has a spring loaded knurled knob on top of the valve/solenoid.

 

[j_martin]

Re: 88 150hp black max hard to start

No adjustment. The knob on some of the early ones is just a manual operator.