Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Overheat alarm on '88 90hp Johnson
Posted by robalo on 05/25/10 - 2:16 PM
#1
Anyone with suggestions on how difficult a job it is to remove the lower unit on an '88 90hp Johnson in order to replace the impeller?? The overheat alarm goes off even after I replaced the thermostats, and I'm guessing the water pump/impeller might be the cause - even though water coming out the tell tale is strong. I cheked the heads when the alarm went off and they are hot. I've never removed the lower unit before and from reading other threads it mentions disconnecting a 'linkgage nut?' so the lower unit can come off but I haven't been able to figure out where that is. Any help would be appreciated. Thanks - Robalo
Posted by Joe Kriz on 05/25/10 - 3:06 PM
#2
I assume when you first run your engine your alarm in not sounding.
Is that correct?
Only after running for awhile does the engine get hot and the alarm sounds?
You might read this article on the warning horn system.
http://www.whalercentral.com/articles...ticle_id=9
Posted by ioptfm on 05/25/10 - 6:32 PM
#3
Sounds to me like your water pump is working. Usually if it's not working you will not have a strong stream. Also, the stream may diminish at a higher speed and that could indicate a bad pump/impeller.
Posted by supwill2001 on 05/25/10 - 10:15 PM
#5
the nut to disconnect the shift linkage is located underneath the carbs, make sure engine is in reverse gear when u remove lower unit
Posted by robalo on 05/26/10 - 7:47 AM
#6
Joe, yes the alarm goes off after the engine has been running a few minutes. After I replaced the thermostats I trailered the boat to the ramp and tested the engine while in the water - on another thread someone recommended this is a better test on these V4 crossflow type engines instead of using the flusher and hose connection.
After watching the video on the ETec I'm thinking it might be best if I let the dealer do the repair for me, I don't have some of those tools. Only thing is the local BW dealer has a few weeks backlog and I hate to have to wait that long to put the boat in the water and start fishing. Fishing season here in NJ isn't that long to beging with. I may look to see if another shop can do the work sooner.
Thanks for the responses,