Several Questions '01 Ospre 175 Tourney

[fishnutz]

Hi All, been awhile since I posted
I have a question that I may be posting in the wrong section, but I'll start here
2001 Osprey Tourney 2001 Merc 90hp 3cyl 2 strokeSolid hull, no soft spots
Complete rewire, has pull ropes on it, need all pumps(fishbox, baitwell, bilge),Lights upgraded to LED(none work at the moment) and have not for a few years
in console made all nice and serviceable in future if needed, new locator, antennae for ship to shore radio or new radio as well

Also, it has a Merc 90hp 2 stroke, makes a knocking noise at slow speed-Idle in gear, other wise goes well, starts good
Thinking about new engine, just cuz I get a little nervous about age, well maintained however
RE: engine, whats the common choice, I know the recommendations will vary, want to stay in the same weight as my present engine,
what would be average cost of all this in the Bonita area(of course I would trailer to Seabob4 as I like his work on here)
Also, can leave at shop from May thru September if needed
OK, ready to read about it
Thanks in advance

[gran398]

If it ain't broke don't fix it.

Keep the 3 cyl. 90 Merc.

 Its a honeypie.

[fishnutz]

Gran, yeah, I really like the engine, it makes a pretty loud knock at idle in gear...I've had a couple guys say all the merc of that vintage and size(3cyl) do it
I've had a lot of smaller Mercs over the years, my 60 3cyl on my 17ft walleye boat was a sweetie as you say, 25, 40, 50 all been good to me
I also have several electrical needs, thankfully the bilge works, albeit no auto float...nest one for sure
Thanks for the reply

[fishnutz]

Anybody on the rest of my questions??
Seabob, any ideas??
Thanks in advance Guys

[slvrlng]

What is the compression?

[futch13]

90-125 hp 3 & 4 cyl Mercs all will rattle when in gear at dead idle especially with stainless props.  The gear cases are spring loaded and as the prop loads and unloads water at idle it jumps the clutch dog.  If you increase the throttle to 900 rpm or so it will/should go away.  Hate to say it but it is normal

[fishnutz]

Futch, yep thats what it does, okay then
Thank You