85 Johnson 150 V6 - no water at tell tale

[dsharretts]

New to me outboard - had water out tell tale one day and zero water at tell tale the next. Didn't know when water pump had been changed so I replaced the water pump - impeller was still intact and didn't look too bad (all arms intact with nothing missing).

Sprayed hose up the water line and had water at tell tale - back flushed water through tell tale hose (using small nozzle on hose) and had water coming out water line. Ran muffs on lower unit while out and had water getting to impeller (intake screens are clean) although no water coming through impeller housing with just water pressure from hose.

Used air compressor to blow back through tell tale hose and can hear air come out water line.

Re-installed lower unit and still no water at tell tale.

I'm working under the assumption that since I had no water with old water pump and no water with new water pump that, obviously, something else is going on. But with the water path apparently not being blocked (water from hose seems to get through) - where do I go next? I've pulled the lower unit and checked the impeller installation 3 times now.

It seems to me that I should get water at the tell tale with the motor running, regardless of the thermostats or current temperature.

Is there a mid point where I can check for water with the lower unit still attached and motor running?

Thanks for any help - this is my first attempt at doing my own service.

 

[emdsapmgr]

You are correct, if the impeller is pumping, you should see water from the telltale, regardless of thermostats or cyl head temps. You can do a test. Remove the lower unit again. Hook the garden hose up to the water tube at the bottom of the midsection. That will flow water up the tube towards the powerhead. If the water tube is clear, you should see water out of the telltale. You can find out about additional flow by removing the thermostat cover and stat. Water should also flow out of there when the block is pressurized. (the garden hose again.) It's possible that the telltale nozzle got plugged for some reason and you changed the impeller. If that water tube was in the wrong position during reassembly, it could have gotten damaged or may be out of place and never got correctly inserted into the top of the impeller housing.

 

[glenn property of pam]

also check the impellor key didn't fall out when being installed. Turn prop while lower is in gear (drive shaft should also turn). If prop turns easy by hand then it would indicate that the key fell out during installation of the water pump. also check the cup is in correctly as I have seen them assembled wrong (if the bolts had to be used to draw the water pump casing down then check the tab at the top isn't bent.)
last test. with muffs put water to the lower and turn the prop to make sure water comes out

 

[Tim Frank]

Is there a mid point where I can check for water with the lower unit still attached and motor running?

Can you describe a bit more clearly how you are testing water pump? Is motor on a boat and in water?

 

[dsharretts]

Thank you for the assistance.

emdsapmgr -Last time, with the lower unit off I did spray the hose up the water tube and did have water at the tell tale - not sure if higher pressure from hose nozzle assisted it or not. I also sprayed the hose through from the tell tale hose and had water come out the water tube. I did confirm that the water tube is inserted in the impeller housing correctly and is not damaged.

glenn property of pam - I'm confident that the key is in place - I watched as the impeller dropped over it. Also, before reinstalling the lower unit, I put the gear case in neutral and turned the drive shaft by hand and I could "feel" and hear the impeller turning. The cup was definitely seated in the housing and I had glued it in place per instructions.

Tim Frank - The motor is on the boat with muffs AND was also on the trailer at the boat landing. I had water at the tell tale with the muffs multiple times previously.

The fact that I had water one day and absolutely nothing the next - my hunch is that something is blocked enough to prevent the lower pressure water pump from getting through - even though the hose nozzle can be sprayed through. Before I remove the thermostat covers I'm going to order new gaskets for them - don't expect them to come off easily.

I had also read on another post to remove the lower unit, put a piece of hose over the drive shaft and clamp it on. Attach the other end of the hose to a drill somehow and run the drill (with muffs on and gear case in neutral). Water should spout up out of the impeller housing.

I think that is my plan moving forward - remove the lower unit (again) and test the impeller as stated above. If the impeller seems to be moving water correctly reinstall lower unit. Then, move on to removing thermostats and covers to see if water is present there.

I can't tell from the water flow diagram in the 85 Johnson manual where the water is getting to the tell tale - they don't seem to have it marked on the V6 diagram like they do the other models.

I'm going to order gaskets and work on testing the impeller. My schedule this week is not good so might take a bit. Any other options or suggestions are still greatly appreciated - please let me know if my plan of attack is flawed. THANK YOU.

 

[emdsapmgr]

Can we back up a minute? After reading this over, I note that you have never indicated that the engine was overheating. No indication of a hot horn. You've not checked the cyl head temps with a laser temp gun to see just what the cyl head temps are when idling. It is possible that the cooling system is functioning normally. The fact that the telltale is not, does not have any effect on cooling capabilies of the engine. It merely means the telltale is not functioning. These telltales do plug up and have to be cleaned, esp if you fish in shallow areas. Have you pulled the telltale hose barb out the exhaust cover to see what's immediately behind it inside the outer exhaust the manifold? Maybe some crud, weeds, etc.

 

[dsharretts]

I'm not confident that the hot horn is functioning and the block is very hot to the touch after running for a few minutes. I've back flushed the tell tale hose and I'm confident it is clear. I haven't removed the hose connection from the block yet to check for obstructions but water does go through both ways using a hose with small nozzle attached.

 

[emdsapmgr]

Just how hot is hot? What are the measured cyl head temps? I may be time to pull the cyl head covers off the heads and see what the water passages look like inside. The gaskets are cheap. Has this engine been in saltwater?

 

[dsharretts]

OK - back at it today. I dropped the lower unit and attached the muffs. I get water through pump by just hand turning the drive shaft in neutral. I'm confident that the pump is moving water - just not sure where it's going. I reassembled the lower unit and started the motor. The water pressure coming out the release hole (on the starboard side, in front of the muff) in the lower unit drops dramatically once the engine is running - which I'm assuming means that the pump is pushing and removing the pressure.

I removed the tell-tale outlet from the engine block and ran the engine again - no water there. Like I mentioned, the Johnson manual that I have doesn't show the tell tale on the water flow diagram but the others do (V4 models) and I'm assuming that it would be very similar - and the diagram only has water flowing there pretty much right when the water gets to the power head.

If I don't have water there that's telling me that the water tube is blocked?? But I know that I can get water through with a hose and a nozzle. And the water stopped at the tell-tale with the old pump and before anything was ever disassembled.

What is behind the two panels on each side of the mid-section? Is any part of the water tube visible behind those? Any where to disconnect a hose between the pump and the power head underneath the engine to check for water there? Assuming that wouldn't be fun but I just can't figure this out.

Thanks.

 

[dsharretts]

Ran hose into tell tale at engine block - water came out through drains in lower unit. Ran engine again and the tell tale hose had a very slight suction??

Does that mean anything to anyone? Again, I'm confident that the impeller is not installed backwards.

 

[emdsapmgr]

Cannot fault your work plan or thinking on the water problem thus far. Must admit it seems a puzzle. Normally when cranking and starting, the pump shoves water up to the engine through the exhaust adapter. The first thing pressurized would be the telltale, so you should very quickly see evidence of the water pump pressure almost immediately after starting. Without much reason, am wondering if you pulled the exhaust covers off the engine-if you'd find any sort of restriction in the water passages between them. Also, pull a thermostat cover off and remove the stat and start it. You should get water out of it. (both if you remove both covers.) To clarify, a telltale is an indication that the water pump is working, not that any water is circulating through (and out of) the block. For instance if both stats are stuck shut, the engine will overheat even though the pump is working.

 

[dsharretts]

Thank you emdsapmgr for your assistance. Looking at the water diagram I think the tell tale is off of the main entry of water to the engine - I'm pretty sure if I don't have water there I won't have any at the thermostats.

That's still pointing me to the water tube. I wonder if it's possible (I guess anything is) that the water tube has come off the grommet that connects it to the engine. Like the pump is moving water but it's just spilling back down through the mid-section. It's weird - the water pressure at and around the lower unit seems to drop when the engine is running like the pump is moving water but it doesn't seem to increase anywhere else - so I'm not sure where it could be going.

I'll have to look into the exhaust covers (I'm not even sure what or where they are). This motor has not been in salt water. But, again, since I don't have water right at the engine/tell tale I keep thinking that something is not right between the pump and the engine - which to me leaves the water tube.

I'm afraid that means pulling the engine - unless there is a way to get at it from the mid-section. I wish I had long camera to feed it up the water tube from the bottom.

 

[Tim Frank]

Have you tried setting up a backflush through the line to telltale?

I've back flushed the tell tale hose and I'm confident it is clear

 

[tblshur]

i may be in left fieldbut with the water hose on all your water discharge should be comming out the prop and the discharge holes above the prop. do you have no water comming out the prop? good luck

 

[emdsapmgr]

Your first post indicated that you put the hose to the water pipe when you had the lower unit off and that you got water a the telltale. That's a normal, good sign. You could have done the same test with the thermostat covers off and check to see if the block fills with water and comes out of the top of the heads. You did indicate that you had water pressure one day, and none the next. A rather abrupt failure. Odd. I suppose it is possible that the water pipe broke or fractured or came loose in the midsection-a really rare failure. Are you sure the water pipe end was snugly fitted into the top of the impeller housing when you re-assembled after the new impeller? If you pull it down again, check it before you drop the lower.

 

[glenn property of pam]

endsapmgr is there a difference between right and left handed lower units. never worked on one myself so I was wondering if you got the odd one from a set of two would everything still be the same?

 

[dsharretts]

The top of the water tube, in the mid-section, was my next target. So I dropped the lower unit again and it seems to be secure. I can pull on it and it doesn't move - seems like it's secure.
Then I went a step further with the lower unit - I attached a 4 inch section of garden hose to the drive shaft and put a hose clamp on it. Stuck a 7/8" drill bit in the other end. I put the muffs on and turned the water on about half way.
Put the bit in the drill and gave it a twist with my hand while starting the drill slowly. Drill was turning the drive shaft (in neutral of course - clockwise) and I had water coming out of the top of the impeller housing. I went one step further and attached a 3' section of hose to the impeller housing (garden hose fits right in the opening).
Held the hose up and started the drill again - again I had water pushing out the top of the hose.

THEN, I figured why not attach the hose straight to the water tube. So I cut a longer section of hose and the water tube fit snuggly right into the garden hose. Ran the drill again and within about 15 seconds I had water coming out the tell tale! That was with about 8' of hose and the water still on only about half way. The other place I had water was out of the exhaust tube - which is what I would expect with the motor not running and thermostats not open.

So - I know the pump works, I know the water path should be clear. The only difference is the motor is not running. I can't come up with anything that would be different with the motor running - other than water exiting the discharge holes above the prop - which I think is where it would come from of the thermostats opened and allowed water through the blocks.

I guess it's conceivable that I'm not getting the water tube into the impeller but that has been my main focus everytime I put the lower unit back on. I can get two fingers in to feel the water tube enter the top of the impeller housing - unless it's somehow dropping out before I get the bolts in.

The thing that's hauting me is why did I not have water with the old pump? If everything was working and I replaced the pump and it stopped working - then sure, I screwed something up. But it stopped working, I replaced the pump to try to fix it and it's still not working even though I think I've proved with this last test that the pump is functioning and the path is clear. I've looked at the instructions that came with the pump kit about a zillion times and I don't think I need any extensions or anything extra.

Seems so simple yet I can't seem to get it going. I've ordered a small inspection camera that I want to run up the water tube just to see whats up there. I may even be able to get it into the tell tale opening on the engine block. That's supposed to show up tomorrow so I think I'll keep the lower off until then.

A really appreciate all of the thoughts on this - keep them coming if any of this triggers anything else.

 

[glenn property of pam]

your water pump does have a piece on top that is held by a screw doesn't it ? Its like a extension the water tube fits in

 

[jakedaawg]

I guess I would check to see that the grommet is in place on the water pump. I f you are getting the water tube into the pump, and it pumps through the hose with the drill, then a missing grommet could explain it all.

Just a silly little thing to mention but maybe...

 

[dsharretts]

Glenn and Jakedaawg - yes there is a cover piece that has two screws holding it in place. The water tube goes into that to connect to the pump. Inside or underneath that is where a tube shaped gasket or grommet goes. Thats installed and in place. I pushed the garden hose down into that to run the test with the drill.