Newbie ???? Mercury 850 Thunderbold Outboard..

I have a older Mercury 850 Thunderbolt and just got it back out of the shop? They replaced the choke on it and the Merc cranked with beauty, but today I was trolling for say a hour and it took 5-7 minutes for the Motor to finally crank? Does this sound like a Carb issue or timing possibly? I would appreciate any info I just got it out of the shop from failing on me and being towed off the lake due to the bad choke. Thanks for any reply or suggestions I have heard that particular motor is very cold natured. Thanks,

Tim

Was the throttle up lever all the way open? Merc love lots of throttle to fire up. Also, the black plastic chokes on some of these carbs tend to distort over time so that they don't seal tightly. Finally, you need to check the choke solenoid to determine if it's working correctly.

Jeff

fastjeff said:

Was the throttle up lever all the way open? Merc love lots of throttle to fire up. Also, the black plastic chokes on some of these carbs tend to distort over time so that they don't seal tightly. Finally, you need to check the choke solenoid to determine if it's working correctly.

Jeff

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Thanks for your reply Jeff I had the throttle in the up position and tried the down position. I have to push the key in for the Choke to engage and it was just replaced last time at the shop. I will check that choke solenoid again the new choke may have quit working. Thanks for your reply..

Tim

Are you pushing AND holding the the choke engaged while cranking ?-------------Have you had instructions on how to start this motor ?---There is no such thing as a " cold natured " motor in my opinion.

put an inductive timing light in the boat and make sure you have fire when it fails....you dont want to work on a fuel problem when the problem is fire or vice versa...

agree with racer....if you got fuel and fire and the motor is turning above 350 rpm then 5-7 minutes is wrong...

racerone said:

Are you pushing AND holding the the choke engaged while cranking ?-------------Have you had instructions on how to start this motor ?---There is no such thing as a " cold natured " motor in my opinion.

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Thanks for your reply I was pushing in the Choke while I was cranking and had the idle lever up in the highest position. Thanks,
Tim

papyson said:

agree with racer....if you got fuel and fire and the motor is turning above 350 rpm then 5-7 minutes is wrong...

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I had the choke Solenoid Replaced the last time it was in the shop. The old Motor ran beautifully with muffs and fired great the first two time on the water, but after we fished for say a hour in temps 30-40 (air) she didn't want to fire back up quickly.