CUMMINS 4BTA3.9-M250 Impeller Prime Issue

[Keith Poe]

CUMMINS 4BTA3.9-M250


Guys I have an impeller issue I need some help with.

I have went though several of them and read all the information on them I can find and checked though everything I read and can think of.


I clean them out really good when I change them super cleaning and flushing no burs and run all day once primed if I do not let it sit to long and loose prime.

The impeller will not suck the water up I have to prime it and if it looses it's prime it burns up.

It works great as long as it's primed.

Thanks for any help.

[CaptPatrick]

Keith,

You've got an air leak on the suction side of the pump, or the impeller cover plate isn't sealing properly.

[Carl]

Hose and fitting going to pump....anything that allows a little air in you'll lose a prime.

Old hoses can get crusty and not seal...even if they went on hard as old hoses do. Also if new hose has wire exposed and not allowing a full seal or fitting not quite round or has a high spot, bur or deep gouge. Fitting connections not sealing, bad shutoff valve.

[Hyena Love]

Have a similar issue with my port Yanmar 240. My boat is on a lift, and I am burning the port impeller about once a year. Other side is lasting three years. Think I am going to try closing the intake valve before lifting her in the future.

My issue arises typically the first or second trip of the season. I change the impeller, and its fine all Summer and then the boat sits over the winter.

[CaptPatrick]

Think I am going to try closing the intake valve before lifting her in the future.

Always, always, close the raw water valves to engines & generator before hauling the boat out of the water and only opening them back up when the boat is back afloat. That practace will save many an impeller...

[gplume]

Don't you guys worry about freezing? I always open to dump the water in the seacock....up here, - 10 f has real good chance of happening....no water - no freze( even salt water freezes atnbthat temp) This is even after flushing whole system with -50 anti freeze...its just that i feed just ahead of the sea cock, thats where i put my antifreeze feeds.

[CaptPatrick]

Gif,

You're right of course, winter storage is a different situation... I'm primarily talking about davit use during warm season, short hauls, etc.

[Keith Poe]

Freeze yes some times it gets crazy her drops down to the fifties and it got up to 85-F once lol love the weather along the coast in the So cal desert.

Found my problem impellers are putting me through a learning curve im not interested in.

The inside of the impeller pump has a floating wear plate that was off slightly preventing the impeller from going in all they way the last 1/8" tearing the back of the impeller rubber up and not allowing the cover plate to seal properly as well.

That SOB on the port was not easy to get in and out balancing act and one wrong more it would fall down during assembly.

also have to shaft log done and back down on the trailer ready for sea trial 4.0

Also repaired a fuel leak from the sending unit gasket.

If I get all the fires put out the fish are gonna get some tag bling sats in hand ready for deployment.

[Hyena Love]

I'm in Houston. We don't really winterize here. In fact, if the wind is not blowing, Jan. and Feb. can be great fishing months along the 100 fathom curve or at our deep water platforms. But, the wind blows. Alot.

[scot]

Mr. Love,

Where is the Hyena machine now a-days with the Bolivar basin gone?

[Hyena Love]

The Hyena has relocated to beautiful Bridge Harbor Marina in scenic Freeport, Texas.

[Keith Poe]

I put about 130 miles on my fourth sea trial she is 100%

[ianupton]

Kieth - great picture of the wake!

[Carl]

You know you got it Bad when you get memorized looking at pictures of a boats wake and you realize your heart is pumping a bit faster then it should....


good shot Keith!

130 miles is a good shake down cruise, I can see you were hugging the coast...just in case.

130 miles is more then most of what my entire dock would run....combined...over the then entire season.

[Rawleigh]

Love that wake! No other boat's looks as good!