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Starting my b97 43lx gen merc engine

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boaterrob

New member
"My cold start procedure on my

"My cold start procedure on my 2 brl. engine of 3 full throttle pumps and 1/3 crack works every time, and if I let it warm up above about 2000 rpms for 30 sec. to a minute, I can bring it to idle of about 400 to 500 and have no troubles. After the warm-up, I can start it with the throttle in idle and it starts right up. The problem comes if for any reason it stops running during the first cold start up. Like if I didn't crack the throttle enough or pull it back too quick and it dies. Once it's died on that first attempt, I can't figure out how to get it re-started. If I use the cold start proc. again, it just cranks and doesn't fire. If I just crack the throttle and try to jockey it around to get it to fire, no good. If I try to start it from idle position, no go. I feel like I'm flooding it, but I don't know how to get it to start when it's in between cold and warm. After all the different start attepts, it usually starts at or near throttle idle after 10 or 15 minutes of trying everything else. Am I flooding the engine? anyone have a good precedure for start if it starts and then dies on the first cold start?"
 
"I would rebuild the carb, che

"I would rebuild the carb, check the choke operation and give it a thorough ignition tuneup, changing worn parts and fuel filters as needed. Clean the flame arrester. You should be able to give the throttle 1/3 of a pump stroke and start it right away. Make sure you use a 1/4" thick carb base gasket and not the thin one in the carb kit."
 
"Thanks Jeff,
would you pump

"Thanks Jeff,
would you pump it once and then crack the throttle? Does the one full pump reset the choke?"
 
"Thanks Guy,
The carb was sup

"Thanks Guy,
The carb was supposed to have been rebuilt about 2 years ago. The boat is new to me this summer. It starts and runs great all other times. I don't know for sure that I have tried just a 1/3 stroke and turn it again. I think my first instinct has been to do the cold start proc. again because it had only been running for a few seconds. Would that be flooding it at that point?"
 
"Sounds to me like your choke

"Sounds to me like your choke is open too much when you first start, and/or it opens too quicky with its bimetal heater unit.
I would check its operation when cold.
Before starting it should be completely closed.
Just after starting it should open to about a 1/8" gap; no more.
Then it should slowly open fully within 3-5 minutes after starting.

Rod"
 
"I thought the 4.3 LX was a 4

"I thought the 4.3 LX was a 4 bbl Weber carb? That is what my 1996 4.3LX had on it.
Regardless, the above applies.

Rod"
 
I put on a reman. carb on my 4

I put on a reman. carb on my 4.3L two years ago and just rebuilt it two weeks ago. Runs better now than ever. The 1/4" base gasket is the key on a 2 BBL carb; very important!! I give the throttle a 1/3 stroke and leave it. Starts immediately.
 
Forgot to say that I set the a

Forgot to say that I set the accellerator pump for the longest pump stroke. Doesn't hesitate anymore.
 
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