1987 50hp Evinrude E50TLCUD Thermostat Replacement

[FishAtFive]

Thanks guys, learned something new today. Looper vs crossflow.

Ok so I put the seal flange in backwards. Can't undo that. My thinking was with the flange point towards the block the thermostat it sat in there better and did not move around when assembling. At least anyone with the same question in the future will find this thread and do it the right way. Based on what I saw removing the old one, I suspect it probably does not make much difference. The old one I couldnt even figure out where the flange went.

I am hoping to take it out on Wednesday for sea trials. Please please please let this fix it. I am tired of it stalling while trying to dock. I got really good at "not going any faster than you would want to hit the dock".

 

[saltchuckmatt]

Thanks guys, learned something new today. Looper vs crossflow.

Ok so I put the seal flange in backwards. Can't undo that. My thinking was with the flange point towards the block the thermostat it sat in there better and did not move around when assembling. At least anyone with the same question in the future will find this thread and do it the right way. Based on what I saw removing the old one, I suspect it probably does not make much difference. The old one I couldnt even figure out where the flange went.

I am hoping to take it out on Wednesday for sea trials. Please please please let this fix it. I am tired of it stalling while trying to dock. I got really good at "not going any faster than you would want to hit the dock".

Why would you not run some kind of corrosion blaster through your motor when you haven't even diagnosed your motor. Nasty looking t-stats tested fine, right? The water orifices in that motor are not very big...plugging is easy.

That motor is not ready for fishing.

 

[FishAtFive]

The old tstat was stuck closed, I finally got it to open at around 170 degrees.

 

[FishAtFive]

Ok reporting back from the dock. Still has the problem of bogging down in gear. The bogging down problem is new, it started the last time I had it out before I changed the thermostat. Here is what happened exactly:

[Last trip before changing thermostat]
I was cruising around, fishing was not good, so on the way back I stopped to fish an old road bed. No luck, so I started the motor to head back to the dock and it would not accellerate, 6 mph tops. I headed back to the dock like that and then it overheated.

So I changed the thermostat. Been meaning to do it anyway. Tested the old one and it was shot so no regrets there.

[Today]
Started a little rough, not idling great. Still the same problem, bogs down and wont accellerate when in gear.

I'm not looking for suggestions. There are very few parts on this motor I have not already rebuilt or replaced multiple times. Either one of the replacement parts are no good or I messed up rebuilding a part. Or maybe there is just something fundamentally wrong with the powerhead. I have to take care of some family business over the next few weeks but if I have time I will go over the basics again. Check the spark gap, pull the carbs, check the floats, check the flywheel key make sure it's not bent, etc. If I don't find anything obvious I think it's time to give up on this one.