SoCal Jet Boats
Tech Talk => Jet Pumps => Topic started by: americanbull on June 14, 2009, 08:13:32 PM
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ok, have a 454 with a berkeley jg pump. new packing gland and transom sealed. at idle there are no leaks from pump or cooling lines. have a valve at inlet line and outlet, both are fully opened. problem at idle the motor heats up to redline but once going its fine. is this because there's not enough water circulating? and then when the water can get through the headers it flows more? other problem is when not at idle (usually above 3000 rpm) there is a leak coming from somewhere. and its a pretty good one. my guess was a hose or something leaking when theres more pressure but I can't find anything wrong. any help....its driving me crazy. nothing like letting off the throttle and have a river come down the center of the boat. thanks for anything ya got
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OK, trying to decipher that. Pretty good description, just my processing skills. Riddle me this, when idling and the forward reverse lever in full forward or reverse, does the boat move?
Ray
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have you checked the stuffing box maybe? either that or a cooling line somewhere is my newbie opinion.
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Most likely possibilities (Berkeley) are Packings (which you've eliminated ) or Bowl to suction housing gasket ?? Call if you need help Tom
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Is this a new problem?
Do you know anything about the history of this engine?
Is it a mk4 or gen5 block?
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idling the boat does moves forward and reverse. it was mentioned to may be a bowl gasket, i'll check that. it doesn't seem to be a cooling line and packing gland is new. the shoe gasket is new and sealed well. i'm thinking its the bowl since i've run out of places to look and that seems to be the last viable option. what do ya think?
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one more time...
Is this a new problem?
Do you know anything about the history of this engine?
Is it a mk4 or gen5 block?
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sorry bout that its an mk4 and this problem has happened since i got it about 4 years ago. don't know the history beyond that. i've pulled the pump and replaced the shoe gasket thinking that might be it but no go. engine runs strong no water in oil just heats up when idling. i had water flowing through the headers all the time before and it never got hot but now that i've corrected the t valve it heats up when water isn't going through the headers.
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Is it possible, and just thinking out loud, that your O/B dump or line to it is clogged up or pinched off with something? Wasp nest, spider nest, Sand?
If it's fine when the header valve opens, the other dumps.........I dunno, was just a thought.
Ray
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not a bad thought but i don't think it is. when idling it does circulate water
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I have heard similar stories when you have Gen V heads on Mk IV block or visa versa. Also if you have the wrong head gaskets or the head gaskets are put on wrong. The steam holes are different on many heads and are easily confused. Also check expansion (freeze) plugs and block drains.
my .02
p-jet