I have a 165 hp mercruiser that i want to machine for quick draining

[bob johnson]

Hello, i have a 22 ft starcraft islander, that i want to use during the winter months in new england. The issue i have is that i will trailer this boat each time i use it. The boat has a mercruiser 165 hp inboard motor. I would realistically have to drain this motor EACH time i pulled the boat out of the water. Since i probably will have to pull this motor at some point out of the boat, because it has not been run in 20 years! while I have it out and apart, i have the idea to install drain petcocks at places that would thoroughly drain the motor to guard against a cracked block.

id like to stay away from installing antifreeze EVERY trip and or buying and installing block heaters id have to run constantly.

does this sound doable?

I am a machinist so i have the facility and means and know how to machine any of the parts i would need to.

thanks

bob

 

[Bondo]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

Hello, i have a 22 ft starcraft islander, that i want to use during the winter months in new england. The issue i have is that i will trailer this boat each time i use it. The boat has a mercruiser 165 hp inboard motor. I would realistically have to drain this motor EACH time i pulled the boat out of the water. Since i probably will have to pull this motor at some point out of the boat, because it has not been run in 20 years! while I have it out and apart, i have the idea to install drain petcocks at places that would thoroughly drain the motor to guard against a cracked block.

id like to stay away from installing antifreeze EVERY trip and or buying and installing block heaters id have to run constantly.

does this sound doable?

I am a machinist so i have the facility and means and know how to machine any of the parts i would need to.

thanks

bob

Ayuh,.... There's Already drain plugs in most All the right places....

1 on the side of the block,...
1 under the manifold,....
1 at the corner of the riser,...
'n, Pull the Big hose off the circulatin' water pump....
lower the drive when ya get to the top of the ramp, 'n again when ya get home, so's it don't freeze, 'n split...

Never any need for Antifreeze anyways,.... Air just Don't Freeze....

 

[artificialreef]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

Isnt that 165 the dreaded 470/aka the 3.7? If so isnt it a closed cooling system with a heat exchanger? Correct me if im wrong doesnt he just have to get the raw water out in freezing temps?

 

[GA_Boater]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

Not the same motor at all. 165 is GM with Merc add-ons and 470 is Merc designed with Ford head.

 

[Bondo]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

Isnt that 165 the dreaded 470/aka the 3.7? If so isnt it a closed cooling system with a heat exchanger? Correct me if im wrong doesnt he just have to get the raw water out in freezing temps?

Ayuh,.... I believe there is a 165 hp 470, but I seem to remember Bob's got the I6 165 hp, Chevy...

 

[bob johnson]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

yes i have an inline 6 thats i THINK is based off a chevy 250 cubic inch motor. it is the factory motor for my 1972ish islander.

bob

 

[Bondo]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

yes i have an inline 6 thats i THINK is based off a chevy 250 cubic inch motor. it is the factory motor for my 1972ish islander.

bob

Ayuh,... Not based on the Chevy I6, it IS the Chevy I6....

 

[ziggy]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

while i don't live in new england, i do live in nebraska. and it does get freezeing cold here too. i also don't use my boat when the lakes are hard, but i do use it into the fall when temps fall below freezing at night. i extend my season by draining the water out of my 165. which isn't so hard to do.
mine is just the common set up i've seen for 165's. one petcock for the engine and two drain plugs. one on the manifold and one on the back of the riser.
from start to finish, i'd guess maybe 20 min. to do the deed. less if i don't have the cover on it.

imho, i don't like the petcock for the block drain that i have. there's no way to prob the outlet for rust scale. after years of use, i know how much should come out and use this knowledge to know whether the block is drained or not.

when i remove the manifold drain plug, i always have rust scale preventing flow. sometimes a little, sometimes full stoppage. i have to probe this hole with a pick to get initial flow. if the drain hole had a petcock, ya couldn't prob it.

fwiw, so far, i can't say i've ever had any water come out of the riser drain hole. i do remove it, but 'so far'. so water has ever come out of it. same with removing the big hose on the ft. of the block. i remove it. but no water comes out. i don't know why this happens to me, but i do remove these two points just to be sure no water is there.

imho, this is pretty darn easy to do. and if i did anything to mod what i have it would be to remove the petcock for the block and put a plug in it's place. reason being is that i could then probe this hole too to be sure it don't have stoppage too.

over winter layup. i use Bond-o's idea. no anti freeze, just air.

 

[Silvertip]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

It was available in 194, 230, 250 and a tall deck 292 iteration and dates back to 1961. The four banger was born from this same design (with two cylinders chopped off).

 

[Don S]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

Back at your original question, you could get fittings such as Mercruiser uses in the newer motor that have plastic wing nut plugs in them.
You need to be able to completely remove the plug so you can stick a nail or screw in the hole to make certain it's not plugged up
Actually, the 1/4" NPT brass hex plugs and a socket and ratchet are just as fast and you don't have to buy all the fittings. But if you would like to use plastic wing nuts, I can get you a part number.

 

[bob johnson]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

why do you have to removed the connection of the water hose on the front?? to allow atmosphere pressure from another side to alow the block to drain???

or are you supposed to allow water to escape from that end as well?

bob

 

[Bondo]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

why do you have to removed the connection of the water hose on the front?? to allow atmosphere pressure from another side to alow the block to drain???

or are you supposed to allow water to escape from that end as well?

bob

Ayuh,... The circulatin' water pump, Can hide up to a quart of water, which is enough to destroy the water pump...

Granted, it's Supposed to drain with the block, but it Don't always do that....

 

[bob johnson]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

Ayuh,... The circulatin' water pump, Can hide up to a quart of water, which is enough to destroy the water pump...

Granted, it's Supposed to drain with the block, but it Don't always do that....

what if i mounted a petcock on the casting the hose clamps to.... then i dont have to undo the hose clamp and pull the hose off, to release the air trap.

just thinking of ways to do this draining that cuts down on the time...many times it is 15 degrees or colder and its already dark when the boat gets pulled up onto the trailer...and id dont want a 1.2 hour proceedure......if i can help it.

bob

 

[Bondo]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

what if i mounted a petcock on the casting the hose clamps to.... then i dont have to undo the hose clamp and pull the hose off, to release the air trap.

just thinking of ways to do this draining that cuts down on the time...many times it is 15 degrees or colder and its already dark when the boat gets pulled up onto the trailer...and id dont want a 1.2 hour proceedure......if i can help it.

bob

Ayuh,.... It takes all of 30 seconds to loosen the clamp, 'n pull the hose...

My motor is the V6, 'n it takes me less than 2 Minutes to drain it, at the launch...

Donno where yer gettin' 1.2 Hours,..??

 

[Don S]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

I agree, with that engne, you pull the plug out of the block and the one out of the exhaust manifold, put the drive down so it will drain too.
While the block and manifold are draining you pull the hose off the front, dump it and put it back on. Make sure the holes are clear on the block and manifold and put the plugs back in, put the drive back up and your done. 5 minutes if you are really slow.

 

[bob johnson]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

the 1.2 was supposed to be a 1/2 ...hey guys the "." and the "/" live right next to each other on the keyboard and i have big fat fingers.



so pulling the hose off , is to DUMP the water there...not just allow air to flow and push water out the drains i opened on the bottom of the motor


right?

10 minutes is fine... 20 minutes or more...is what i dont want...

there is already a 20 minutes proceedure to get the boat road ready after i put it on the trailer

bob

 

[Bondo]

Re: I have a 165 hp mercruiser that i want to machine for quick draining

the 1.2 was supposed to be a 1/2 ...hey guys the "." and the "/" live right next to each other on the keyboard and i have big fat fingers.



so pulling the hose off , is to DUMP the water there...not just allow air to flow and push water out the drains i opened on the bottom of the motor


right?

10 minutes is fine... 20 minutes or more...is what i dont want...

there is already a 20 minutes proceedure to get the boat road ready after i put it on the trailer

bob

Yes...