1981 J8RCIC Johnson 7.5 No water from tell tale

[sixdeep]

hey guys, i seem to have resolved most of the issues with my 90hp thanks to the help from here. I just fired up my 7.5 to test it before going to the lake next w.e and it started fine but the tell tale was spluttering water, no steady stream. It's not progressed to only blowing air and no water.
I've blown some compressed air from the fitting on the motor and it blows bubbles out the intake so it wouldnt appear to have a blockage. My initial thought is the impelllor isnt sealing enough to pump water or is not spinning with the shaft. Any one have any ideas?
I tried to drop the lower unit but cant get it out. Googled around and found some info on 50s era johnson little motors who say you have to take the power head off. I undid 6 bolts that look like the hold it on and gave it some gentle taps with a soft mallet and no movement. I know it hasnt been removed in the last 10 years and perhaps never at all. Looks like the paint is intake around where it mounts. Can anyone confirm they are the only bolts to be removed and i just need to be a bit more forceful to remove it? Or if there is another way to disconnect the shift linkage to remove the lower unit?

Appreciate any thoughts or help.

 

[kbait]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

You don't have to remove powerhead on that one... that was for 50's and early 60's models. You just move the shift handle in forward position (may have to move the prop to get in gear), remove the 3 lower unit mounting bolts, and pull the lower unit off. The entire shift rod should come out w/lower unit. "the shift rod and drive shaft will come free of the powerhead" is what the service manual says for your model.

Good luck!

 

[sixdeep]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

No joy. Wont budge, moves a few mm front and back but seems firmly stuck in the centre. Drained the gear fluid as well but still stuck. Fluid looks clean though, no water in it which is good at least.

 

[tazrig]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

Sixdeep, here is a link to the OEM manual for your motor. I've linked you to page 8-17 which starts to go over the lower unit and its removal with pictures. This should help. Use the arrow buttons at the bottom of the page to turn the pages and hit the plus sign to zoom.

Boatinfo - 1971-1989 Evinrude Service manual

You can also go back to page 1 with this link as it has an index for everything about your motor and how to service it.

 

[sixdeep]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

Thanks heaps. Checked it, seems like the shift rod is stuck. Lower unit wont budge. Powerhead also wont budge =(
saw it has a thermostat. just pulled that off in the dark and tested in boiling water.seems to be working. will try and run water through the tell tale and thermostat housing tomorow. see if i can clear something. may just have to get vigorous on the power head =(

 

[Vic.S]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

Thanks heaps. Checked it, seems like the shift rod is stuck. Lower unit wont budge. Powerhead also wont budge =(
saw it has a thermostat. just pulled that off in the dark and tested in boiling water.seems to be working. will try and run water through the tell tale and thermostat housing tomorow. see if i can clear something. may just have to get vigorous on the power head =(

Shift rod is unlikely to be stuck. Most likely problem is the drive shaft stuck (rusted) in the crankshaft..
Eventually if you get really brutal the drive shaft will pull out from the gear case and the pump impeller key will wreck the water pump housing as it pulls out of the pump (Luckily when I did it I had a plastic key in there so damage was minimal but the OEM keys are metal!)
You could try turning the engine upside down an running some release oil down the shaft via the exhaust outlet.

To get the power head off you will probably need to rock it fore and aft to break the joint (it wont rock sideways!) but you cannot rock it until the drive shaft is out!

If you do take the power head off inspect/replace the grommet and retainer at the top of the water tube

 

[sixdeep]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

Thanks for the info Vic. the reason i said the shift rod is thats what the service manual suggests is stuck if the lower unit wont drop. I just ran water from a hose through the thermostat hole and it came out the telltale fine. fitted the cover and flushed water up the telltale, water came out the lower unit but on closer inspection it seems to be coming out the exhaust rather than the water intake.

Surely that isn't normal? What does it suggest?

 

[nwcove]

Re: 1981 J8RCIC Johnson 7.5 No water from tell tale

ive had some success freeing up stuck driveshafts by loosely bolting the lu back up( use all three bolts), and running the engine in gear for a few mins.