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Stocksick55

Mercrusier 496 air pump

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I have the air pump drain system. I can't get enough pressure to build up to make the green pegs pop out. Some water comes out but it doesn't seem like enough. I sucked up enough sand a few weeks ago to clog the starboard manifold. I got an alarm and my temp was just over 175 on the gauge.  Normally the temp stays below 175. I shut it down and got towed back. I replaced the impeller thinking it would be destroyed but it still looked really good for being 3 years old. I pulled all fresh water hoses and flushed. Boat runs great. 6.5 Psi water pressure at 1,000rpm. I've put 7 hours on it since the incident. I'm not sure why the drain doesn't work now?

I'll also be pulling the drive this winter to replace the trim sender and limit switch. Any tips? looks fairly easy. Do I need  gasket for a Bravo 3? 

2006 256SSi 496 B3

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8 hours ago, Stocksick55 said:

I have the air pump drain system. I can't get enough pressure to build up to make the green pegs pop out. Some water comes out but it doesn't seem like enough. I sucked up enough sand a few weeks ago to clog the starboard manifold. I got an alarm and my temp was just over 175 on the gauge.  Normally the temp stays below 175. I shut it down and got towed back. I replaced the impeller thinking it would be destroyed but it still looked really good for being 3 years old. I pulled all fresh water hoses and flushed. Boat runs great. 6.5 Psi water pressure at 1,000rpm. I've put 7 hours on it since the incident. I'm not sure why the drain doesn't work now?

I'll also be pulling the drive this winter to replace the trim sender and limit switch. Any tips? looks fairly easy. Do I need  gasket for a Bravo 3? 

2006 256SSi 496 B3

Good idea to pull the drive to check u-joints and engine alignment, but no need to do so to replace the trim sender/senders. If your drive has a three wire sender with a flat cover on the port side (digital trim limit) then you can use the retrofit kit which replaces the trim position sensor on the starboard side with a plastic blank cover, and the supplied sender for the port side doubles as both trim limit and trim position. This only works if the existing unit has 3 wires, and connects to the "digital" pigtail located inboard just above the bell housing. If your existing port side sender is two wire then you will need to replace both senders.     Pull the trailing end anchor pin from the trim cylinders which allows the drive to be lowered all the way down to it's mechanical limit. By doing so, a small access slot will appear above the bell and gimbel ring, just big enough to get a 1/4" drive extension, universal joint, and 7/16" short socket in there to remove the 1/4" retaining bolt and cable clamp. Turning the drive full right helps with access too. Inboard, when you disconnect the plug in harness, you will need to attach a pull wire to the old wires, and from outside pull the old wires out and the pull wire through. Tape the new wires together to keep the transom seal properly aligned, and have a helper pull them through with the pull wire while you guide them in from outside. He then keeps a slight tension on the cables (I use a bungee) to keep the cable seal landed, while you re-install the retainer, and bolt. No room in there for fingers, so I use a small rod with the clip taped to the end, and I also tape the bolt into the 7/16" socket. Take a few tries but not all that difficult.

Before you re-install the trim cylinder anchor pin, rotate the white plastic eccentric bushing 180 degrees to allow for an additional 1-1/4" trim in. On that boat, you will really see a positive change in hole shot and additional adjust-ability on a less than perfect day. As far as the single point drain system goes, it takes very little volume to get the poppets to indicate, so my guess would be that you have a small leak in the trigger tubing. There are two pneumatic remote actuated drain valves on that system, and a flashlight and mirror will confirm that they are both opening.   W

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Great info Wingnut! Thanks! I’ll take a look at my trim pucks tonight and also check for air leaks on the air pump system. 

I flipped that bushing two years ago after seeing one of your other post. What a difference!

I was also going to pull the drive to check my drive oil resivior tube. I think it may be pinched. I never loose any and I can’t get the oil pumped up to it after an oil change. Do I need a new gasket to reinstall the drive?

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6 minutes ago, Stocksick55 said:

Great info Wingnut! Thanks! I’ll take a look at my trim pucks tonight and also check for air leaks on the air pump system. 

I flipped that bushing two years ago after seeing one of your other post. What a difference!

I was also going to pull the drive to check my drive oil resivior tube. I think it may be pinched. I never loose any and I can’t get the oil pumped up to it after an oil change. Do I need a new gasket to reinstall the drive?

Your drive does not have a gasket. There are three o-rings sandwiched between the gimbel and drive, and another 3 on the drive input shaft. They come as a kit.  You do not want to re-use the old ones.    W

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14 hours ago, Wingnut said:

Good idea to pull the drive to check u-joints and engine alignment, but no need to do so to replace the trim sender/senders. If your drive has a three wire sender with a flat cover on the port side (digital trim limit) then you can use the retrofit kit which replaces the trim position sensor on the starboard side with a plastic blank cover, and the supplied sender for the port side doubles as both trim limit and trim position. This only works if the existing unit has 3 wires, and connects to the "digital" pigtail located inboard just above the bell housing. If your existing port side sender is two wire then you will need to replace both senders.     Pull the trailing end anchor pin from the trim cylinders which allows the drive to be lowered all the way down to it's mechanical limit. By doing so, a small access slot will appear above the bell and gimbel ring, just big enough to get a 1/4" drive extension, universal joint, and 7/16" short socket in there to remove the 1/4" retaining bolt and cable clamp. Turning the drive full right helps with access too. Inboard, when you disconnect the plug in harness, you will need to attach a pull wire to the old wires, and from outside pull the old wires out and the pull wire through. Tape the new wires together to keep the transom seal properly aligned, and have a helper pull them through with the pull wire while you guide them in from outside. He then keeps a slight tension on the cables (I use a bungee) to keep the cable seal landed, while you re-install the retainer, and bolt. No room in there for fingers, so I use a small rod with the clip taped to the end, and I also tape the bolt into the 7/16" socket. Take a few tries but not all that difficult.

Before you re-install the trim cylinder anchor pin, rotate the white plastic eccentric bushing 180 degrees to allow for an additional 1-1/4" trim in. On that boat, you will really see a positive change in hole shot and additional adjust-ability on a less than perfect day. As far as the single point drain system goes, it takes very little volume to get the poppets to indicate, so my guess would be that you have a small leak in the trigger tubing. There are two pneumatic remote actuated drain valves on that system, and a flashlight and mirror will confirm that they are both opening.   W

I do have the three wire sender with a flat cover on the port side. What is the part number for the retrofit kit? I looked online and I found 8M0095310. It looks like I still need to pull the new wires through and connect the 3 wire plug?

My gear lube reservoir tube seems fine. I cut the tube just before the drive and new gear lube ran out the boat side and just a bit of used oil ran out the drive side.

No luck with the air pump lines. I couldn't find a leak. I disconnected and reconnected all of them. I can feel the pistons on the water pump and distribution block going up and down. Are they supposed to stay open? I don't use this system to winterize. I run antifreeze, I just don't like things to be broken. 

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https://nuwavemarine.com/oem-quicksilver-mercury-trim-sender-assembly-8m0095310/?gclid=EAIaIQobChMInoWe1-373QIVHYezCh3BbwjyEAQYBCABEgJcCPD_BwE

The starboard side is just a blank. Once installed you will need to do a trim calibration through your smart craft. The new sender has a one piece transom seal, not the split wedge you see on the old sender pair. The sender wires get pulled through before you attach the gang connector. The 3 contacts slip right in just be sure to match the color code and placement from the old connector.

The air actuated valves open at a lower pressure than do the indicator pop-ups. Used mine yesterday during winterization, and the valves open after the first 2 pumps of the bicycle pump, but in order to get the indicators to pop up you need to get pretty aggressive with the pumping. The air will stay in the air manifold until you pull the pressure relief ring on the air manifold. I drain the flush water out, relieve the pressure, and suck in 4 gallons of Prestone Marine R/V antifreeze into the raw water system, which takes a little over 10 seconds with the engine running at idle. I then leave that material in the engine until spring.

When you pull the drive you will find a poppet shut off valve the seals as soon as the drive is pulled away from the gimbel to prevent draining of the elevated reservoir. If you do pull the drive, then you could hold in on the poppet to see if oil drains from the engine mounted mini-tank. Maybe the poppet is broken, or the small opening in that valve is plugged.     W

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4 hours ago, Wingnut said:

Once installed you will need to do a trim calibration through your smart craft.

I do not have a smart craft gauge. I have the analog cluster. Will the retro fit still work? 

 

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1 hour ago, Wingnut said:

Yep, just a bit more work to install.

Do you recommend pulling both sets of wires through together or one at a time?

Thanks again for all your help!

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Tape the wires together with masking tape just ahead and behind the transom seal halfs.  Attach your pull wire at a point that provides for equal cable lengths to the deals.  Once you get the inboard end through keep tension on the wires so that the seal halfs remain landed, seated, and aligned while reinstalling your retaining clip.  Could you post a picture of your two bolt clip?   W

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28 minutes ago, Wingnut said:

Could you post a picture of your two bolt clip?  

I have the single bolt clip. 

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13 hours ago, Stocksick55 said:

I have the single bolt clip. 

Thanks. When I hear something that is contrary to the norm I always like to see it so we can all learn. Good news is you will only have one to get back in there. They are a pain even on a good day.  W

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