Mercury 200 HP Compression

[spareparts]

hit the cylinders with a can of power tune decarb spray. Let it set over night, cranks it up, blow all the power tune out and recheck your numbers. If the carbs are set up correctly, it should start from cold by just holding the key in while spinning the motor over, once it hits, it will stall, then try to restart, momentarily holding the key switch in, it will start, but try to die out, when it stumbles, bump the key switch in for a sec, it should pick right back up, after about 30 secs it should idle on its own. Let it warm up a bit before putting it under load

[Duke01]

Thanks for the tips regarding the starting sequence. I will try what you have both described. I don't think that I have used a consistent approach regarding pushing the key in while cranking thus far.

I was not aware of Quicksilver Power Tune. Just placed an order.

Thanks again, Duke

[Duke01]

Regarding my starting issue, I have started (without starting fluid) on my last two outings. Pushing in the key three times before turning the key switch, while throttling up a bit with the key in. Now I just need to fine tune the process.

Thanks again...

[spareparts]

Originally Posted by Duke01

Regarding my starting issue, I have started (without starting fluid) on my last two outings. Pushing in the key three times before turning the key switch, while throttling up a bit with the key in. Now I just need to fine tune the process.

Thanks again...

the only time pushing the key does anything is when you are spinning the motor over, or if you just pump ed the primer bulb up good and tight. All pushing the key in does is open a valve that allows fuel to flow in behind the carbs, enriching it. It rely on the fuel pump or residual pressure in the line to push the fuel in. Try holding it in while spinning the motor over

[phatdaddy]

Like Spare said , the ball pressurizes the system and the fuel pump move the fuel. If you haven t change the diaphragms in the pump in a while, might be a good idea to do so.

Pretty cheap and easy to do. I would also use OEM merc parts

[jamesbalog]

Mine always gave me a fit first start of the day and then would run fine the rest of the day with just a bump of the key.

Best way I found of the cold start was make sure the bulb was Hard, advance throttle about 1/3 of the way out of gear and start her up. Might take a few turns of the key but once she fired let her sit that way for a minute or so and then I was good to go.

Another thing I learned if I turned both batteries on she always started quicker.

My compression numbers were 125-130 across all 6 before I lost the 1 cylinder

[Duke01]

Very similar situation for me, tough to start, but never stalls, runs fine, idles fine. I troll with a new Tohatsu 9.8. Good luck on your search for No. 4