Difficult to start cold 7.5 merc

[PaulO]

I find I have to squirt fuel up the carby throat to make the engine start.

Once it is going it is fine at idle and in the start position. When it is hot is starts first pull. I can't say the choke helps it any.

I was hoping giving it a run under load might help clear any possible build up on carby bits?

Any ideas? This engine was sitting for eight years.

 

[Texasmark]

Re: Difficult to start cold 7.5 merc

My 7.5 was cold natured also. Ran like a top otherwise and was like that right out of the crate.

Mark

 

[PaulO]

Re: Difficult to start cold 7.5 merc

So Texas, have you done anything to try and fix it or do you just accept it the way it is?

 

[Bubbles Up]

Re: Difficult to start cold 7.5 merc

My 79 7.5 Merc is also quite cantankerous to start, when cold.It starts fine when it is hot.
I ran into a gent at a lake he would actually store his engine next to his furnace,then on the way to the lake he had a silver foil insulation blanket ,using the sun to "preheat the engine" .
I personally don't know if it helped,but I see the theory.

 

[Laddies]

Re: Difficult to start cold 7.5 merc

You have a lean condition could be a idle is set to lean, the choke is not completely closing or the float level is to low. Last but not least if ever thing else is ok nthe rings could be a little sticky so it will need to be soaked with powertune.

 

[Texasmark]

Re: Difficult to start cold 7.5 merc

So Texas, have you done anything to try and fix it or do you just accept it the way it is?

I accepted it. "Don't like to fix it if it ain't broke". Actually most of my outboards have been like that unless I used them every day. Lawmowers with Kohler engines and float type carbs are the same way. If I run them every few days, they start right up. If they sit for a couple of weeks or so, it's grind, grind, grind. On them, I just shoot some starting fluid in them just to save wear and tear on the starter.

On a 2 cycle OB, the only "starting fluid" I would use is Deep Creep, Sea Foam in an aerosol can. It contains lubricating oil which 2 cycles definitely need.

One thing that annoyed me about that engine was the cowling. It was nice and stylish and all, but the hole (notch-whatever) where the starter handle was located was small and awkward for me to get my big fat hand in there......the old late '40's early '50 vintage Johnson had the right idea; put that sucker right out there where you can get your hands on it.

I haven't had the engine for 15 years I guess. Sold it to a collector friend. I ran it on a 12' Lowe Line, Lake John and it would really make that sucker scoot.

Mark

 

[PaulO]

Re: Difficult to start cold 7.5 merc

My engine was difficult to start today. I gave it a couple of hours run. I brought it home , adjusted the tab on the float so it is roughly level with the float metal. I let it stand for 3/4 hour and tried starting it. it went first pull.

I bet it will make a liar of me I will report back at a later
date.

FYI the tab was bent higher than the float frame.