Cracked Suction Piece

[bowtiejunkie]

I'm not versed on jets, so excuse any wrong terminology. A cousin of mine just bought mid-1980's jet boat, with a Berkeley Jet pump (looks closest model 12JG from looking at Berkeley's website). He didn't do a water test before buying. We took it out Sunday and had basically immediate failure (cracks 3-4 inches long) of Suction Piece at 10 o'clock a 2 o'clock position in area where it bolts to bowl. Looks like a disc or similar pierced through. Metal shavings were everywhere along with a ton of water pushing in. It first broke through on Starboard side of Suction Piece. We noticed it, but tried to make it back to ramp, when boat engine overheated. That's when we noticed a ton of water in boat, and the port side of suction piece cracked. Had to get towed back to launch ramp. Did the wear ring, impeller, or pump shaft left go?

I also noticed a good leak at what I believe is the Suction Piece seal.

I'm curious what went wrong. Any idea on costs to fix this?

We had engine cooling problems too (which I'm not sure if this is related to Suction Piece developing cracks). 454 BBC. Engine would run hot (240+) idling in no-wake zone, then start cruising and it would cool to below 200* (could feel outlet hose was cool), but the engine temp would jump past 250* within a few minutes. We had valve on exit hose open all the way. Any ideas?

Thank you.

 

[Elkidmino]

Any pics of the cracked housing? 3 point or 4 point engine mount?
Does it have a loader (ramp into the intake under the boat)? Or no grate on the intake?
Does it have a t-stat in the housing? Block might be full of sand.
The water valve was on the outlet hose? Weird, usually it's on the inlet hose on the pump.

The impeller is after the suction piece, contained in the bowl out of the back of the boat. If that went it would crack the bowl, not the housing. If the the rear engine mount failed it would put a load on the pump snout that might crack it.

 

[bowtiejunkie]

Any pics of the cracked housing? 3 point or 4 point engine mount?
Does it have a loader (ramp into the intake under the boat)? Or no grate on the intake?
Does it have a t-stat in the housing? Block might be full of sand.
The water valve was on the outlet hose? Weird, usually it's on the inlet hose on the pump.

The impeller is after the suction piece, contained in the bowl out of the back of the boat. If that went it would crack the bowl, not the housing. If the the rear engine mount failed it would put a load on the pump snout that might crack it.

Thank you for the reply. My knowledge is limited on the boat's setup and I didn't take any pics. I pulled a pic from the internet and marked in RED where the suction piece has been cracked



I didn't look under the boat, so unfortunately, I don't know if there is a loader or grate on intake. Engine mounting is unknown as well as we didn't remove the engine cover. I wish I could help this along better, but I didn't do a lot of poking around the boat.

So, the water inlet for engine comes off the suction piece, with a gate valve in-line? That makes sense why the water was cold on that line. Is there an outlet as well? Some water must go through the exhaust logs; is there another water outlet? The intake manifold has an aluminum water outlet divider tee (the type where a thermostat will not fit under). Is it normal to run a thermostat or do you control the temp via the intake valve on water inlet line. Maybe there's something clogged in the water inlet hose or elsewhere.

Seller is supposed to meet my cousin at boat in storage and take a look. Sucks to buy something and it fail big first time out.

 

[Elkidmino]

Yes, generally there is a gate valve on the water inlet to the engine off the suction housing. See that threaded hole at the bottom right of your pic? That's where a piece of tube screws in and then a gate valve is screwed on. Yes water outlet is usually out the exhaust at the snails/risers. It's 50/50 on the decision to run a thermostat or not. I didn't run one on my old boat and just used the gate valve and a pressure gauge on the intake manifold coolant port to regulate the water (stay under 15psi @ WOT).

As for the cracks, those seem very odd at that location. I haven't seen that failure before, but that's not to say it hasn't happened. Maybe someone with more experience can comment.

I HAVE seen leaks at the suction housing to bowl housing gasket. If water sits in there over winter and freezes it'll screw that gasket up at the bottom or push the threads out. I had to replace mine on my boat because it was spraying water into the bilge! The other location that is common for leaks is at the packing, the area where the driveshaft connects to the pump shaft in the flange. The packing rings get dried out or worn out and then it leaks streams of water out both sides when the engine is running. You might be seeing that leak, and misinterpreting where the leak is coming from. Or the inspection cover is leaking, check the nuts/wingnuts holding down the cover.

Let us know what happens. You're going to have to run it with the engine cover off, someone driving and someone in the back looking for leaks with a flashlight. It'll be apparent real quick.

Pic of gate valve (this pic has a relief valve added):

 

[jetboatperformance]

Your suction housing is not cracked but rather "cut" through ... most likely your thrust bearing has failed allowing the impeller to walk forward and gouge into the housing Its a wonder the boat apparently did not sink must have a healthy bilge pump . There no simple repair here sans a rebuilt or replacement jet drive call if We can help Tom

 

[bowtiejunkie]

Yes, generally there is a gate valve on the water inlet to the engine off the suction housing. See that threaded hole at the bottom right of your pic? That's where a piece of tube screws in and then a gate valve is screwed on. Yes water outlet is usually out the exhaust at the snails/risers. It's 50/50 on the decision to run a thermostat or not. I didn't run one on my old boat and just used the gate valve and a pressure gauge on the intake manifold coolant port to regulate the water (stay under 15psi @ WOT).

As for the cracks, those seem very odd at that location. I haven't seen that failure before, but that's not to say it hasn't happened. Maybe someone with more experience can comment.

I HAVE seen leaks at the suction housing to bowl housing gasket. If water sits in there over winter and freezes it'll screw that gasket up at the bottom or push the threads out. I had to replace mine on my boat because it was spraying water into the bilge! The other location that is common for leaks is at the packing, the area where the driveshaft connects to the pump shaft in the flange. The packing rings get dried out or worn out and then it leaks streams of water out both sides when the engine is running. You might be seeing that leak, and misinterpreting where the leak is coming from. Or the inspection cover is leaking, check the nuts/wingnuts holding down the cover.

Let us know what happens. You're going to have to run it with the engine cover off, someone driving and someone in the back looking for leaks with a flashlight. It'll be apparent real quick.

Pic of gate valve (this pic has a relief valve added):

Thank you for the info on cooling. I'd been awhile since last on a jet boat. Used to working on cars and trucks, so rough entry back into world of jet boats. lol.

Your suction housing is not cracked but rather "cut" through ... most likely your thrust bearing has failed allowing the impeller to walk forward and gouge into the housing Its a wonder the boat apparently did not sink must have a healthy bilge pump . There no simple repair here sans a rebuilt or replacement jet drive call if We can help Tom

Thanks Tom. Yes, I should have more appropriately stated these were "cuts" not cracks as the water flow into the boat was quite impressive. My cousin mentioned he talked to you a few days ago. I think he said he sent you pics and a video. I told him plain and simple, to tow it to you for the repair and pay you to look over the cooling.

Luckily we were in the outer limits of boat launch no wake zone at Millerton lake, the bilge pump didn't fail, and we got a tow to the ramp. If that bilge pump had quit, it would have sunk no doubt, even with the tow.