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Hi,
When does the weak pee stream appear? Let me answer my own question:

Weak pee stream right after start up. After the engine runs for a bit, the pee stream "dries up".

Is that fairly accurate?

If so, then my thought is that the engine's coolant passages are partially plugged.
When the engine is cold, water is blocked from going to the head and a more forceful stream is directed through the intake manifold and directly out the tell-tale.
But, when the Tstat opens, a large portion of the flow is directed through the cylinder head in a parallel path. That cuts down on the flow going directly through the intake manifold and out the tell tale passage.
You could get an idea of how bad things are by pulling the stat and looking in there for mineral/salt build up
I suspect it is overheating some even though you don't "feel" that it is.
However, it could be something (debris, minerals....even little rocks) has plugged the intake manifold bypass (tell-tale) passages or hoses. You could try just cleaning out the manifold and replace the hoses.
Those hoses get very hard over the years and can break internally creating a debris trap. Almost all original hoses cannot be reused and will likely come off in pieces. They are no longer available and you would need to make your own replacements if you disturb them.

You also need to know that, if you do pull the intake manifold, that you might be forced to also make your own gaskets. There are some slight differences between the year models and, while some of the gaskets are still available, some are not.

I have attached two links from the parts supplier www.boats.net below to illustrate this. Notice the differences in the hoses and the fact that, in the first link, the gaskets (items 2 and 3) are still supported while the gaskets are listed as unavailable in the second link for that vin number series.

Honda Outboard 7.5HP OEM Parts Diagram for Inlet Manifold | Boats.net

Buy OEM Parts for Honda Outboard 7.5HP Inlet Manifold Diagram
www.boats.net www.boats.net

Honda Outboard 7.5HP OEM Parts Diagram for Inlet Manifold | Boats.net

Buy OEM Parts for Honda Outboard 7.5HP Inlet Manifold Diagram
www.boats.net www.boats.net

But, hey, there's plenty of gasket making material available and, with some patience, you can knock those out on the workbench. Been doing that for many years.

With lots of PB Blaster on all fasteners a week before disassembly...some hair dryer heat.... and some patience.... these old twins aren't too bad to work on and are tough as nails.
 
jgmo said:
Hi,
When does the weak pee stream appear? Let me answer my own question:

Weak pee stream right after start up. After the engine runs for a bit, the pee stream "dries up".

Is that fairly accurate?

If so, then my thought is that the engine's coolant passages are partially plugged.
When the engine is cold, water is blocked from going to the head and a more forceful stream is directed through the intake manifold and directly out the tell-tale.
But, when the Tstat opens, a large portion of the flow is directed through the cylinder head in a parallel path. That cuts down on the flow going directly through the intake manifold and out the tell tale passage.
You could get an idea of how bad things are by pulling the stat and looking in there for mineral/salt build up
I suspect it is overheating some even though you don't "feel" that it is.
However, it could be something (debris, minerals....even little rocks) has plugged the intake manifold bypass (tell-tale) passages or hoses. You could try just cleaning out the manifold and replace the hoses.
Those hoses get very hard over the years and can break internally creating a debris trap. Almost all original hoses cannot be reused and will likely come off in pieces. They are no longer available and you would need to make your own replacements if you disturb them.

You also need to know that, if you do pull the intake manifold, that you might be forced to also make your own gaskets. There are some slight differences between the year models and, while some of the gaskets are still available, some are not.

I have attached two links from the parts supplier www.boats.net below to illustrate this. Notice the differences in the hoses and the fact that, in the first link, the gaskets (items 2 and 3) are still supported while the gaskets are listed as unavailable in the second link for that vin number series.

Honda Outboard 7.5HP OEM Parts Diagram for Inlet Manifold | Boats.net

Buy OEM Parts for Honda Outboard 7.5HP Inlet Manifold Diagram
www.boats.net www.boats.net

Honda Outboard 7.5HP OEM Parts Diagram for Inlet Manifold | Boats.net

Buy OEM Parts for Honda Outboard 7.5HP Inlet Manifold Diagram
www.boats.net www.boats.net

But, hey, there's plenty of gasket making material available and, with some patience, you can knock those out on the workbench. Been doing that for many years.

With lots of PB Blaster on all fasteners a week before disassembly...some hair dryer heat.... and some patience.... these old twins aren't too bad to work on and are tough as nails.
Click to expand...
Wow !!! Thank you very much for a very detailed and informative Reply reply Appreciate it
 
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