Bf20d fresh water pump no telltale even after blowing air backward through hole

Title pretty much says it all.
The overheat beeper went off and no telltale. Freshly rebuilt water pump. I blew some compressed air backward through the telltale drain and bubbles came out the lower unit. Fresh water.

Thoughts?

Well....if you installed the water pump correctly and you didn't dislodge the drive key (which is easily done sometimes btw) then my guess is that that you may have missed getting the water tube inserted properly into the grommet at the engine block water passage inlet.. See the dotted line square in the upper right of the parts page blow up in the link below.

https://www.boats.net/catalog/honda/outboard-by-hp-serial-range/20hp/bf20d3-shta-2003

You don't say how old the engine is but I have found the mounting surface that the grommet sits in can be badly eroded on older, salt water used outboards. If that's the case a grommet could actually be:"wadded up" in the inlet and virtually no water can enter the engine.

You didn't say what condition the old pump was in but if it was missing pieces of the impeller arms, that could form a plug in either the engine inlet or the tell-tale bypass or both. A thorough accounting of all the pieces is required to make sure no blockages occur.

In either case, you'll need to drop the gearcase again and investigate if you think I might be right.

Good luck.

If you do have an eroded water tube grommet surface I have reliably repaired a couple using epoxy and it worked well. It's not easy and the powerhead has to be removed but it's definitely "doable".

If you just need a new grommet it is item 2 in the link below.

https://www.boats.net/catalog/honda...20hp/bf20d3-shta-2003/oil-case-oil-pan-gasket

Again,
Good luck

You note "fresh water", just wanted to say I've seen them fill up with sand.....

I've hooked a hose directly to the pipe leading up from the water pump to make sure it was clear. If the thermostat housing is off, there should be quite a fountain coming from that when you turn the water on!

I didn't have time today to pull the lower unit off that boat but I'll have time to get to it on Monday. I might try the water hose on the up pipe from the pump first just because it's a little more accessible.
That grommet looks like a PAIN to get to but such is the job.
Thanks for the help! This is only my first post but I'm positive I'll be spending lots of time on this forum.

Did it pee before this work was done ?---Testing in a bucket ?-----Water must be above impeller to work properly.

Solved the problem.
The downpipe to the lower unit was crooked and found itself misaligned

Simplest problem first huh?
Thanks for the input everyone, I'm sure I'll be back!

Well, it's actually an "up-pipe" (delivers the water up to the engine) in "my mind". But...then...I am referring to "my mind" which, as it turns out, is a complete MESS!

Other than that, I think you DONE GOOD!

Thanks for the update.