Merc 165 replacement options

[paparoof]

I've got a 1975 Starcraft Islander with a dead (presumably original) Merc 165 motor. Water was in the cylinders for god knows how long before I bought it, it's locked up tight.

As I'm squirting WD40 in it and trying to get it moving, I'm also shopping for donor boats that I can rip the motor out of.

Can I get a list of motors besides the 165 that will bolt right up? Or am I locked into the 165?

 

[ohioriverrat]

Re: Merc 165 replacement options

where are you at? i have a 470 / 170 same engine that runs pretty well ill sell for cheap if you come get it. im in WV right on the ohio river.
the problem with my engine is that it needs the carb cleaned and a voltage regulator, but it starts and runs strong.

 

[ohioriverrat]

Re: Merc 165 replacement options

sorry, the answer to your question depends on a couple things. you are probably rockin a alpha outdrive and alot of engines will bolt up. however - if you change engines you will need to change out all kinds of stuff like exhaust Y pipe, throttle and shift cables and probably several other things to be sure. better off to stay with what cam in it unless you want to buy a full drop in kit

 

[stonyloam]

Re: Merc 165 replacement options

I've got a 1975 Starcraft Islander with a dead (presumably original) Merc 165 motor. Water was in the cylinders for god knows how long before I bought it, it's locked up tight.

Straight 6 or Merc 4?

 

[paparoof]

Re: Merc 165 replacement options

Minneapolis
and
Straight six chevy 250

 

[Fishermark]

Re: Merc 165 replacement options

Your best bet is to find a Chevy 250 to put back in there. There are some other straight sixes that work, I THINK, but the 250 is fairly common still and would be by far the easiest swap. It's also a good, simple, dependable engine.

One thing to be aware of is to try and get one with the provision cast in the block for the front mount. Not all 250 engines had that provision. It can be overcome... but just something to watch out for.

 

[paparoof]

Re: Merc 165 replacement options

sigh... alright, I guess I'll keep to just searching for 165's.

besides some kind of lift to get the motors in and out and an alignment tool, are there any other specialty tools I'll need for the swap?

Is there a thread on here showing detailed pictures of the job? I've been searching and searching and finding nothing.

 

[nuboat2me]

Re: Merc 165 replacement options

paraproof...

Check your PM.

Thanks!

Nuboat2me

 

[ziggy]

Re: Merc 165 replacement options

besides some kind of lift to get the motors in and out and an alignment tool, are there any other specialty tools I'll need for the swap?

nope, pretty much just your mech. hand tools and your trusty mercruiser service manual.
if your shade tree like me. you'll need some kinda set up like this.

the only thing that can be an obstacle may be that you need to lift the engine high enough to clear the boat, + the chain hoist long enough to reach the ground or eng. stand height so as to remove the engine from the boat. unless the hoist has a real long chain, you'll probably use the full length of the hoist.

as for removal. i did mine last week or so, and it's pretty much like the book. s/m #2 has the items for removal and replacement.

edit. that red thing i got in between the hoist and the engine is a pretty dandy item. an engine leveler (allows you to tilt the engine fore and aft while on the hook) i think it's called, but not sure of the name. don't know if ya gotta have one, i don't but my neighbor does, and it sure makes manipulating the engine when on the hook around to your likings very easy.

 

[windsors03cobra]

Re: Merc 165 replacement options

The ole 250's are not as common as they once were. I just looked on car-part.com and searched for a motor for a 75 nova and there were several results in your area.
They come in 2 flavors integral intake and non integral intake.
The integral intake has the intake built into the head and you wont be able to use the head, if your head is reusable you might be able to use one of these engines.
I had a cracked block 165 and posted a want ad on craigslist and the very next day a guy from a town over offered a good running 76 Nova 250 for $100 it had the integral head and the MerCruiser engine mount on the timing cover. I bought it and used my old head and it has been a great motor.
So you might try a want ad, you never know what people having laying in there garage. This Nova engine was complete, on an engine stand and freshly pulled from a Nova to make way for V8.
I'm sure it has some miles on it but its a straight six, they are tough.

I used the marine cam along with brass freeze plugs and my other marine engine accessories.
I've only changed one other I/O in my life and it was a 4.3 and it literally took me 2 hours to get the 165 out. Straight sixes are always so easy to work on, in my hull anyway.
www.car-part.com

 

[windsors03cobra]

Re: Merc 165 replacement options

On second thought that $900 drop in and go is going to be the way to go in your case I think. It looks as if most your engine accessories are junk and the drop in has a new looking alternator.

Cool boat, good luck with her.
Is that green oil seeping from a pitted lower unit ? Ai yi yi.

 

[paparoof]

Re: Merc 165 replacement options

On second thought that $900 drop in and go is going to be the way to go in your case I think. It looks as if most your engine accessories are junk and the drop in has a new looking alternator.

Cool boat, good luck with her.
Is that green oil seeping from a pitted lower unit ? Ai yi yi.

Yeah I was close to spending 1500 on a rebuilt longblock, but that doesn't come with a carb or alternator, etc.... so if mine are indeed junk I'd quickly be up over 2 grand to get the rebuilt running. That $900 used one is looking like a great solution, even if just a temporary one. My current block has NOT been diagnosed as cracked (yet) so I may get it rebuilt slowly while using the $900 motor in my boat. Then I'd have TWO complete, working motors - I could put the extra one in my 14-foot Sea Nymph !!!

 

[paparoof]

Re: Merc 165 replacement options

And yeah, that green drip from the lower unit is next on the list after I get a running motor. Think JB Weld is a sufficient first attempt to attack that drip or is that just stoopid?

 

[paparoof]

Re: Merc 165 replacement options

Hey I brought home a used 165 motor today. Got the hoist and leveler last weekend. Gotta buy lumber and build the gantry this weekend.

Is this the right alignment tool?
LINK

 

[ziggy]

Re: Merc 165 replacement options

Is this the right alignment tool?

looks similar to what i got. from what i get. the alignment bar is the same for all set ups. omc, bravo, alpha, vp. all use the same alignment bar. the vazer has a new bar though, best understand.
so yes. that's what ya need. yer gonna like having one. wish i'd have got mine sooner than later. now i have no reason at all not to pull my drive. love my alignment bar...

Hey I brought home a used 165 motor today. Got the hoist and leveler last weekend. Gotta buy lumber and build the gantry this weekend.

sounds like ya got a plan to me.. way to go..

 

[Kainon]

Re: Merc 165 replacement options

BTW, I have a 250 from a '74 Nova, the cam is not the same, hopefully the marine cam will run a little better.

Also check the wood under the front motor mount with a straight edge (even a 12" Ruler) mine was sagging, and I think causing some of my rumble, when I replaced it the drive went in by itself, Ok, it had a little help, but seriously it was so dead on straight I was beside my self, and i had replaced the transom. ( wish I could've upgraded to a Alpha with PS.

Good luck on the replacement.