1999 15HP 2-stroke. Few quick questions

[DocTide]

Hello! Got a 15HP Mercury from a buddy and had a few quick questions. Its a simple enough manual, tiller model I plan to convert to remote in the future.

Now my question- The LU has quite a bit of paint chips, no corrosion, but a bunch of areas that do not have paint and chipping. I wanted to know how bad this is, and should I go ahead and get it painted? I have researched plenty and it seems that Zinc Chromate primer is needed for the bare aluminum, and perhaps epoxy primer for areas with paint. I read somewhere Mercury Phantom Black was a solid strong paint to use. DO I have to paint it, will it oxidize over timer, what would you do? Those are my questions.
On the topic of painting, If I do decide it is better (per advice on this forum) would it be acceptable to sand down and Zinc Chromate prime the bare metal spots, and then sand the paint and go over the entire outboard with epoxy primer, even over the Zinc Chromate spots? Seems more logical than sanding ALL the paint off. Let me know.

EDIT: Also the other questions I was concerned about- The foam padding on the inside of the cowling is VERY flaky and old. It seems that since the carb has no filter in front of it for the air, some of the debris might find its way to clogging a jet. Is this a real problem? I might be a little paranoid but after years trying to get my RD400 motorcycle running I and always wary about carbs and things like this. Should I remove it, and replace it?

 

[flyingscott]

I would make sure there is no water in the lower unit and that it works correctly before i paint it. That lower unit is not the most durable and almost impossible to find used. take care of the mechanical then paint zinc primer is fine and mercury paint is good

 

[Mi duckdown]

throw pics at us

 

[DocTide]

So, I just pulled carb and lower unit. Impeller kit on the way along with thermostat, carb repair kit, gasket/seal kit, new plugs and fuel lines. Is there anything else I forgot that probably should be replaced with the entire engine starting to come apart? This is not my first rebuild (3.3HP merc and 5HP Nissan, along with RD400 motorcycle complete rebuild) so I am pretty good with understanding lingo and asking questions.

One thing I have noticed is that there is quite a bit of white pitting inside the prop shaft housing (looking into the prop). I need a harmonic balance or gear puller to get this sucker out I am assuming- can anyone recommend a decently priced one that will fit here? Most of the screws I have taken out are siezed up in the threads, I got myself some Tef-Gel, but am wondering if I should head down to come depot and replace the screws themselves with new SS ones.

Back to the original question as well, you think painting is in order?

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