Air coming out the telltale engine cooling line instead of water

[bigtexan99]

Confirm you connected hose at the fitting next to engine compartment

No, I connected the water hose to the fitting at the back of the jet pump, on the left side of the pump looking to the front of the boat...just above the exhaust.



The fitting you circled in red was closed, I actually forgot about that connection point even existing.

 

[gazzaskirepair]

So in the next pic u connected hose to red ring connection ?

The green ring is the water supply to engine during normal operation

Are your running engine with jet pump off

If you follow the tell tale line from boat body exhaust you can cut the tie wraps on exhaust side and push a piece of wire inside to make sure it’s clear I don’t know if an old coat hanger wire will work
Also check the elbow on the cylinder head is clear too
You may have to remove elbow to get the wire into cylinder head

Can you show on picture where the water was coming out
Send a pic of impeller to wear ring clearance too

 

[bigtexan99]

Appreciate your help in running this down! Did you mean to attach another picture with red and green circles? I did not see one.

The jetpump is installed on the boat.

Ran 2 tests today.

1. Water hose connected to back of boat (in green) to the left of the jet pump. Water only came out the exhaust (in red) none came out the sidemounted tell tale or the 2 tell tales below the tow hook.



2. Water hose connected to the top mounted flush port (next to the oil fill, under the rear hood). Again water came out the exhaust (to the left of the jet pump), nothing out the sidemounted tell tale and about 5 drops came out one of the tell tales below the tow hook.

Won't be able to try your suggestions on using a coat hanger or wire till this weekend.

 

[gazzaskirepair]

Ok it’s basicallly using the flow diagram disconnecting hose and either putting air through or water the hoses and fittings if you use water them you’ll get a little water in bilge
Check the fitting and cylinder head and use hose to put water through that hose and you should get water out the jet pump impeller area

 

[bigtexan99]

Okay, thanks. I read you're not supposed to run water through the engine without the engine being on, how do I prevent any damage while doing this testing?

 

[gazzaskirepair]

Disconnect the tell tale lines on engine exhaust to confirm the fittings are not blocked too

You can blow low pressure air through
Water through hose at cylinder head will come one out around the impeller and doesn’t need engine running Do that first
Then flush engine from the fitting next to jet pump with engine running and with hose of at cylinder head off you should have water coming out elbow

You could also remove the temperature switch on cylinder head and leave it electrically connected and see if water comes out there

Run engine for as little time as possible

You are basically trying to identify where your blockage is

 

[bigtexan99]

I disconnected everything a section at a time and flushed water through everything including the temp probe. No blockages that I could find. Water flowed easily through the cylinder heads.

There was a little resistance on the intake to the water regulator (lower nipple on part 20 on the red and blue diagram) but I gently blew air through the line and it gurgled and then flowed fine.

The only thing i noticed that might have been an issue is that on the T nipple part #27, the line going to the water regulator (#29 on the diagram) did not have a zip tie or clamp on it. It was fairly snug, but I'm wondering if that could have been where it was sucking air into the system. I added a zip tie to it.

Put everything back together and started the engine on the trailer then added water through the connection on the top left side of the jet pump. For the first time in a long time, the water seemed to be flowing normally! Good steady stream out the side mounted pisshole.

Not sure when I'll get to the lake to really test it, maybe this coming weekend but I'll be sure to post an update.

 

[gazzaskirepair]

So sounds like your a winner

 

[bigtexan99]

Went to the lake today with great hopes, but came home with dismay.

Pretty much the same symptoms, mostly air coming out the piss hole with spurts of water.

Greased up the driveshaft zerk fitting before I went out and the cavitation was much less.

When I got home, I ran a few tests and took some video. Any input appreciated!

1. This is the water pressure/flow used for the tests.
waterpressure_fortests.mp4

2. This is the first test, with the hose connected at the rear next to the jetpump.
Test1_water_at_jetpump.mp4

3. This is the second test, with the hose connected at the top mounted connection, next to the oil fill.
Test2_water_at_oilfill.mp4

4. This is the 3rd test, same as the first test but with better lighting. Hose connected at rear next to jetpump. Test3_water_at_jetpump.mp4

 

[gazzaskirepair]

Don’t run boat in step unless you blank off the connection to the left of jet pump
Your just running water in and straight out

 

[gazzaskirepair]

Can you send a diagram how the tel tales are connected
Did you notice any water coming out of impeller area inside the back of steering nozzle
If not then you have a blockage between exhaust and Eng exhaust manifold
Are you getting overheat alarm while on the lake

You may have too many tell tales so there’s no back pressure ( saying that were is the air coming in )

Are you riding in fresh water

 

[gazzaskirepair]

I am wondering if it’s worth while to pull the regulator and check the diagram is not punctured or torn
Have you had a steady stream from the boat in the past

 

[gazzaskirepair]

The big clear hose in the video is connected to where as it seems to have air also as it’s pulsating

 

[bigtexan99]

Don’t run boat in step unless you blank off the connection to the left of jet pump
Your just running water in and straight out

I'm not sure what you mean?

 

[bigtexan99]

Can you send a diagram how the tel tales are connected
Did you notice any water coming out of impeller area inside the back of steering nozzle
If not then you have a blockage between exhaust and Eng exhaust manifold
Are you getting overheat alarm while on the lake

You may have too many tell tales so there’s no back pressure ( saying that were is the air coming in )

Are you riding in fresh water

Yes, there is water coming out to the right of the steering nozzle..you can see the stream in Vid #4 (Test 3 with better lighting.) at about the seven second timestamp.

I did pull the regulator yesterday, but I have not opened it yet. Its on my kitchen counter.

The boat is used in fresh water. The boat is not overheating while on the lake. While on the lake the engine cylinders are relatively cool to the touch and the exhaust pipe is noticeably hotter to the touch as are the water lines exiting from the exhaust pipe.

I noticed all that air pulsing through the clear line in the video as well, but don't know what it means. That clear line goes to the intake of the regulator (the lower connection).

Yes, for many outings on the boat the output stream of the tell tales was clear and steady. I checked my boat operation and maintenance log, and the only thing that I worked on before the stream started getting erratic was the fuel pump on the carb, it needed to be cleaned and I replaced the fuel line that feeds it.

Pulled the jetpump again and measured the clearance on the wear ring, its .020. Here are a bunch of pictures of it. impeller – Google Drive

As for the diagram of the tell tales, its all OEM except for the one rerouting of the hose from the exhaust pipe. In the picture on post #12 Air coming out the telltale engine cooling line instead of water I have rerouted the line (part #7) from the top of the exhaust pipe. It no longer goes to to the pisser #14. Instead it goes thru the hull just under the throttles and exits there so I can see it stream while driving the boat. Tomorrow I'll get in the boat and make sure that the Y connection (#14) is still capped off.