Thanks for the vids. Your info was perfect for my 1988 Mercury Classic Fifty 45hp with WMA-7b's. Rebuilt the carbs and fuel pump. For those of you with the SAME Mercury setup, the initial idle screw adjustment should be about 1 1/4 turns out from lightly seated. Fine tuning should be done IN THE WATER (not just hooked up to the hose) AT IDLE SPEED (700-800 RPM) and IN FORWARD GEAR. These conditions add additional drag, so the carbs must compensate. The procedure (alternate CARB1, CARB2, CARB1, CARB2, ....) is to back the idle screw out (counterclockwise, counting turns as you go) BY 1/8 TURNS until the engine bogs down due to a RICH condition, then tighten (clockwise, counting again) by 1/8 turns until the engine stutters/backfires from a LEAN condition, then back out (counterclockwise) 1/4 to 1/2 turn. You should end up near the initial setting in the 1 to 1 1/2 turn range. The 1/4 to 1/2 turn gets you to a happy medium and allows for having enough fuel available for quick acceleration and for safety (see WARNING). You should end up near the initial setting in the 1 to 1 1/2 turn range. WARNING: If there is error, the error should be on the side of making the engine run RICH, otherwise a LEAN condition could not provide enough engine lubrication and BURN IT UP! Your responsibility...don't come crying to me!
Appreciate you watching my video and your comprehensive instructions on how to set the idle! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
Justin Finley Appreciate you watching my video and your nice comment! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
I purchased a used 1997 Mercury 40 with this same exact carb (currently not running). When I took the carb apart mine didn’t have the internal gasket on the bottom of the fuel bowl in either carb. Would the missing gasket cause it not to run? I can tell someone has been in the carb before because the top carb float is newer. Thanks for the video!!!
Thanks for watching my video Absolutely! For my 1996 Mercury 40HP 2 Stroke, there are two things to make them go in synch. First is the shaft between them. It needs to be set so that they both open and close their butterfly valve's at the same time. You can see that by looking in the throat of the carbs. Then you just need to set the mixture screws at the same point for both. Best, The Sailor.
+Brennan Urbaniak Look for Permatex #2, non-hardening form-a-gasket sealant. You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
Thanks for watching my video! Correct. Check the space underneath the float for what I mentioned in the video. You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
brian robinson Thanks for watching my video and your informative comment! It can only help the community! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
Thanks for watching my video! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscibe for the latest! Best, The Sailor.
Six years later and your video has helped me with my float problems. Thank you very much.
Thanks for the vids. Your info was perfect for my 1988 Mercury Classic Fifty 45hp with WMA-7b's. Rebuilt the carbs and fuel pump.
For those of you with the SAME Mercury setup, the initial idle screw adjustment should be about 1 1/4 turns out from lightly seated. Fine tuning should be done IN THE WATER (not just hooked up to the hose) AT IDLE SPEED (700-800 RPM) and IN FORWARD GEAR. These conditions add additional drag, so the carbs must compensate. The procedure (alternate CARB1, CARB2, CARB1, CARB2, ....) is to back the idle screw out (counterclockwise, counting turns as you go) BY 1/8 TURNS until the engine bogs down due to a RICH condition, then tighten (clockwise, counting again) by 1/8 turns until the engine stutters/backfires from a LEAN condition, then back out (counterclockwise) 1/4 to 1/2 turn. You should end up near the initial setting in the 1 to 1 1/2 turn range. The 1/4 to 1/2 turn gets you to a happy medium and allows for having enough fuel available for quick acceleration and for safety (see WARNING). You should end up near the initial setting in the 1 to 1 1/2 turn range. WARNING: If there is error, the error should be on the side of making the engine run RICH, otherwise a LEAN condition could not provide enough engine lubrication and BURN IT UP! Your responsibility...don't come crying to me!
Appreciate you watching my video and your comprehensive instructions on how to set the idle! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
Thanks, good info
Justin Finley Appreciate you watching my video and your nice comment! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
I purchased a used 1997 Mercury 40 with this same exact carb (currently not running). When I took the carb apart mine didn’t have the internal gasket on the bottom of the fuel bowl in either carb. Would the missing gasket cause it not to run? I can tell someone has been in the carb before because the top carb float is newer. Thanks for the video!!!
Where did you replacement float for this carb?
Hello
thanks for nice video!
maybe you know how is necessary to make carbs synchronization on Mercury 40hp 96 2 stroke???
Thanks for watching my video Absolutely! For my 1996 Mercury 40HP 2 Stroke, there are two things to make them go in synch. First is the shaft between them. It needs to be set so that they both open and close their butterfly valve's at the same time. You can see that by looking in the throat of the carbs. Then you just need to set the mixture screws at the same point for both. Best, The Sailor.
What type of sealant are you using. I don't recognize that label locally. Thank you.
+Brennan Urbaniak Look for Permatex #2, non-hardening form-a-gasket sealant. You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
so you adjust from the carb flange to the dead top not the corner just below.... of the float(upside down)
Thanks for watching my video! Correct. Check the space underneath the float for what I mentioned in the video. You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
Whatever you do don't break the bottom bowl screw "high speed jet". Can't get them. Mercury has obsoleted many parts.
brian robinson Thanks for watching my video and your informative comment! It can only help the community! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscribe for the latest! Best, The Sailor.
Sealant is a mistake, ethanal breaks it bown and then sealant particals end up in jets . No sealant required, NFG!
Thanks for watching my video! You may like my other videos. Just type Lsailor1 in the UA-cam search bar. Like them? Subscibe for the latest! Best, The Sailor.