165 Mercruiser Q. and Intro.

[imported_Kendall]

Good afternoon,

I'm Kendall. After selling 2 boats years ago to do the "responsible thing," I'm now ready to jump back in, only I'm starting small as finances are spread. I've done quite a bit of searching, which is how I found this forum, but I finally gave up and decided to take a more direct approach. I don't have an engine problem, but this seemed to be the best place to post my question.

I'm looking at a 1976, 18' Sea Ray with a 165 Mercruiser. I've always heard that the ol' Chevy Inline six was a bulletproof engine that only suffered a bit for mileage.

1. What can I expect for reliability and longevity out of the 165 rig?

2. How about power?

She'll mainly be a fishing boat, but could likely see some skiing action. I don't figure I'd do that great pulling 250 lb. slalom skiiers up, but what about 130 pounders, like the Mrs., even though she's more into wakeboarding these days, bless her heart.

3. What's the general concensus of the 165?

Thanks so much,

Kendall

 

[ziggy]

Re: 165 Mercruiser Q. and Intro.

i'm on my 2nd il6. i like them just fine. nice and easy to work on too. as for longevity, i don't know, but they seem pretty darn durable to me. but not indestructable. my last one had a crack in a headbolt hole. why i don't know. but it ruined my block. guess ya'd need to do some testin of the engine to know how yers stands. compression test, leak down test etc. power wise its more than adequite. when i was yonger (like 16 or 17)we got 3 up on skis behind a 16' trihull. 2 slolomn and one on two skis. so i bet it'll get 250 lbs up. also, had some fella stop by a few times out ago. he had him a baja type boat. he was commenting on my speed and was surprised i only had a il6. that made me pretty happy coming from a speed demon baja guy. as for fuel consuption, i don't know the facts. but it seems to be good enough for me. bet it's better than some out there.....like a v8 i'd think. lets see if i can put some context to it. from memory (it's failing ya know the older i get)i went 51 miles up river, agaist a 2-3 mph current. and used 9.5 or so gal. at cruisein speed. 2600-3000 rpms. went much faster down river, maybe 3300-3800 and used maybe 10-11 gal. but got back pretty fast goin with the current. that was with a 21p prop which i think was to much for it. got a 19p now and is much better. i think their very good engines for a boat....

 

[qaztwo]

Re: 165 Mercruiser Q. and Intro.

Have one in a 1972 rinker. Had to replace the engine a few years back, 30+ years not bad in my book. Good engine, idle nice and smooth, good gas milage, parts all over they place. I'm 200 and it pulls me out just fine on one ski.

 

[imported_Kendall]

Re: 165 Mercruiser Q. and Intro.

Have one in a 1972 rinker. Had to replace the engine a few years back, 30+ years not bad in my book.

That's still a bit disconcerting as I'm looking at a '76.

What failed that required a full replacement?

 

[ziggy]

Re: 165 Mercruiser Q. and Intro.

i just got one kendall. a boat with a 165 in it that is. it's a 75. picked it up this sept. i had to replace the manifold. other than that, it seems pretty healthy. has resonable compression and runs real good....... don't be disconcerted. they are good engines. my il6 in my older boat (72 trisonic) was runnin on 4 cyl. for all practical purposes. if i'd not done a compression test i'd not have even known that i was sol. if it really needs a engine ya can get em for between 1200 and 2500 depending on where ya get the rebuild, remanufacture. personaly i'd be more worried about the boat than the engine.....i would not have got this 75 aristocraft that i got now if my old boat was in a condition to drop a different engine in it. but it wasn't. it needed stringers, drive and a engine .......an old boat can be just as fine as a new one imho if it has been cared for proper. if it hasn't. it's a crapshoot at best. for any part of the boat.....my biggest worry about my aristocraft is the boat, not the engine......at least that's the way i feel about it anyways.......

 

[imported_Kendall]

Re: 165 Mercruiser Q. and Intro.

i just got one kendall. a boat with a 165 in it that is. it's a 75. picked it up this sept. i had to replace the manifold. other than that, it seems pretty healthy. has resonable compression and runs real good....... don't be disconcerted. they are good engines. my il6 in my older boat (72 trisonic) was runnin on 4 cyl. for all practical purposes. if i'd not done a compression test i'd not have even known that i was sol. if it really needs a engine ya can get em for between 1200 and 2500 depending on where ya get the rebuild, remanufacture. personaly i'd be more worried about the boat than the engine.....i would not have got this 75 aristocraft that i got now if my old boat was in a condition to drop a different engine in it. but it wasn't. it needed stringers, drive and a engine .......an old boat can be just as fine as a new one imho if it has been cared for proper. if it hasn't. it's a crapshoot at best. for any part of the boat.....my biggest worry about my aristocraft is the boat, not the engine......at least that's the way i feel about it anyways.......

I agree that the boat could be tired. I plan to thoroughly check the condition of the wood as much as possible without stripping her down to bare bones, look for stress cracks and anything that might lead me to believe that she hasn't been cared for. In pictures she looks like she's led an easy life, but there's nothing like the personal touch.

At that cost, a new engine would double the price of the boat. I've heard of guys buying street I6s and modifying for salt and saving gobs of cash.

But what about an outdrive of that age?

 

[ziggy]

Re: 165 Mercruiser Q. and Intro.

But what about an outdrive of that age?

drain the lub out of it and see if ya get some metel with it, or water in the lub. pressure and vac. test it to see if the seals are good. ya could pull the drive to check inside the bellows for gear oil too but the pressure test will let ya know if yer leakin or not i beleive. once the drive is off ya can check the u-joint and gimble brg. too + lubem up. i didn't have my drive pulled prior to buyin. but i did test drive, listening for gimble brg. growl or vibrations from the u-joint in tight turns or trimmed up high.

the boat i just got i had the pressure test done 2 times. once prior to a test drive, once after. and the lub got changed once to R&R the impeller, once to pressure test the 1st time and one more time to pressure test the 2nd time. so 3 times prior to buyin it. i just changed it again for the winter and got nice green hp gear lub out of it after 20-30 hrs use by me.....i consider myself to be ok for now......

 

[qaztwo]

Re: 165 Mercruiser Q. and Intro.

A crack formed between two cylinders. I had a bad intake/exhaust manifold(later found out) and water was dumping down into one of the cylinder. Would cause the boat to stall out occasionally. Ran the engine like this for years. I know this caused the crack.

 

[ParallaxBill]

Re: 165 Mercruiser Q. and Intro.

I have a second owner 1973 Glassmaster with a 165 Mercruiser L6. Mine is all original with a lot of hours but it has been well maintained. It has great power, runs smooth and has shown no problems whatsoever in the 3 months I've owned it. The previous owner never had any problems with it either. Not just his word. The motors are pretty much bullet proof and reliable. I've had a Chevy version in a 78 pick-up and my father in law owned a 76 GMC pick-up with the 250 L6 and neither of us ever had any general engine problems the entire time we owned our trucks.

Now granted, some WILL say "but marine motors are different" which could be true but these GM L6's are also closer to truck engines than many folks might believe. The main differences are the cooling system & intake/exhaust manifold. Everything else is basically equal to the truck motors. Certainly no worse, maybe even better,

In fact what sold me on my old boat was the fact that I know the motors well and I could keep it in top shape easier than any other engine besides a Chevy or GM V8.

 

[imported_Kendall]

Re: 165 Mercruiser Q. and Intro.

Thank you for the help, gang.

I tested the boat at dusk, in the rain in Portland, OR's Willamette River off Johns Landing. It was pretty gutless for a 16.5' boat. It was acting cold, or something, but the guy made it clear that he was surprised it got up and went so well with 4 people in it. That was enough for me. Later he mentioned that the carb may need cleaning, or a rebuild. I would guess he may have been correct.

I had looked at 3 other boats that day. I called the lady with the '89, 19' Blue Water open bow and made her an offer she couldn't refuse. O.K., no horse heads in her bed, or anything. Just a solid offer. This boat has a very health sounding Chevy 350 (5.7) Merc. I didn't test driver her, but did put her in fwd and rerverse and swing the outdrive around. Her maintenance records were extremely solid. I have a very good feeling. I plan to take her out on a shakedown in a few days before I put her to bed for the winter.

Thanks again,

Kendall

 

[imported_Kendall]

Re: 165 Mercruiser Q. and Intro.

In fact what sold me on my old boat was the fact that I know the motors well and I could keep it in top shape easier than any other engine besides a Chevy or GM V8.

Another reason I opted for the the ol' 350. Greatest engine, ever! With a little timing adjustment (just before ping/knock,) my father got over 20 MPG out of 3, 350 equipped, classic Vettes.

 

[Bondo]

Re: 165 Mercruiser Q. and Intro.

Make Sure you do your research,+ see which Ign. Module you have,+ it's built in Advance,....

You could be Unpleasently Surprized if you're not Careful bumping the Timing on a Boat Motor.........

Good Luck...........

 

[ziggy]

Re: 165 Mercruiser Q. and Intro.

It was pretty gutless for a 16.5' boat. It was acting cold, or something, but the guy made it clear that he was surprised it got up and went so well with 4 people in it. That was enough for me. Later he mentioned that the carb may need cleaning, or a rebuild. I would guess he may have been correct.

might have needed more than that too. sounds like ya made a good choice in not gettin that one. it should have performed much better than that. i hardly know (maybe just a little exauration, but not much) i got 4 people in my 19 footer... jumps right up on plane...yer new 350 will be a good engine for ya too i'd think. though i don't know about the turnin up the timein to just before it detonates bit..that sounds a little scary to me.... enjoy yer new boat man.......congratulations.......