318 engine block drain plug(s)

revitalizingtheoldgirl · Fri Sep 28, 2012 1:00 pm

We are going to try to save some money by winterizing our 1973 F25 ourselves. Hoping to save time by inquiring where is the drain plug on the engine block? Is there only one? Any helpful hints for the do it yourselfer would be great. Tired of paying someone $400+ to do it. Taking out next Friday

Stripermann2 · Post by **Stripermann2** » Fri Sep 28, 2012 1:40 pm

Ther are two drain plugs on either side of the block, as in most V8s.
Number 18 in diagram.

The Dog House · Post by **The Dog House** » Fri Sep 28, 2012 5:30 pm

There should also be a drain plug in the center bottom of each exhaust manifold. Even if you are pulling the drain plugs, still make sure to run pink antifreeze through the engine first. There are places like the water pump and hoses that will not drain when the plugs are pulled. When you do pull the plugs (engine and manifold), make sure you have a bucket underneath because a lot of antifreeze will come out.

revitalizingtheoldgirl · Fri Sep 28, 2012 5:50 pm

So it sounds like we're looking for 4 plugs then. Okay. No place for a bucket in the enigine compartment so we'll be connecting a length of hose to reach from the deck to the intake in order to get the antifreeze into her. Buckets on the exhaust to catch what's going through and a bucket under the hull drain to catch what we drain from the engine. Will 4 gallons of the pink stuff be enough? Want to make sure we're doing it right. Don't want to find out next spring we missed something when we winterized the block.

larryeddington · Post by **larryeddington** » Fri Sep 28, 2012 6:37 pm

There also may be one at the base of the riser. I installed in each engine petcocks in lower block, exhaust manifold and the base of riser.

revitalizingtheoldgirl · Fri Sep 28, 2012 7:20 pm

What/where the heck is the riser? Will the plug be easily found on it?

Big D · Post by **Big D** » Fri Sep 28, 2012 7:45 pm

Ok, I just have to interject! Considering you are family, I must do what I can to help you enjoy your boat next spring and summer. I see this far too often come Spring time because somebody wanted to safe a little money in the Fall. I'm getting a little worried based on the questions you're asking, and we can attempt to answer them but every application/boat is different so we can't foresee/answer/advise about something you may be overlooking. There are also subtle things that we each may take for granted and not mention because it's simply second nature to us or think that it's simply common sense so may not mention it like probing the drain holes to make sure there is no silt blocking the rest of the water from draining, draining all hoses, coolers, etc. Don't get me wrong, very willing to help here but I always recommend paying someone one last time with the agreement that you will watch and participate in what they do and take notes if you must so you can do it yourself the following year. I see it like this; $400 now, or perhaps a new block and more ($$$), and half of next season gone. Just thought I'd put it out there because I am 100% sure I will be dealing with somebody's cracked blocks next year becuase they wanted to save money and went into it blind. At the very least, get help from a boater friend that has done his own for a few years.

revitalizingtheoldgirl · Fri Sep 28, 2012 8:18 pm

Appreciate the input, understand your concern. We have read and reread the manual on winterizing and we have a guy with a much larger boat that's been doing it for more than 10 years himself that will hopes to be available the day we take out. Just hoping to get input from trojan owners since his boat is very different than ours. Tried being there the past couple years when we paid to have it done but they could never give us a day and time, just when they could fit it in their schedule to travel over to our marina and do it. Figured this was the best place for some good sound advice/input. We hold ourselves fully responsible for any oversights in winterization. Lots of people have said oh it's easy just do this or that. So we want to make sure what we have read and heard meshes with others' input.

Big D · Post by **Big D** » Fri Sep 28, 2012 9:55 pm

Fair 'nuff. Don't want to assume anything so; are you fresh water cooled (coolant in engine with heat exchanger) or raw water cooled (lake water through engine)? If fresh water cooled, block does not get drained but raw water circuit/side does. If exhaust manifolds are fresh water cooled, they don't get drained either. If engine is raw water cooled, everything; block, exhaust manifolds, hoses, cooler, everything. Remember to probe all drain holes with a wire or something, I actually like using a simple zip tie, I like that it is flexible and bends allowing me to spin it inside the block, manifold, etc. Probably no muffler but if you do, drain it also. If you have a hot water heater with a heat exchanger that uses engine cooling liquid and your application is raw water cooled, the lines from the engine feeding the hot water heat exchanger must be drained as well as the exchanger. Remove as much water from everything as possible, this will ensure you do not dilute the anti-freeze and reduce its protection. Hope that helps.

You will likely have two plugs per exhaust; one in manifold and one under the elbow. One per engine block side (2) and one in the cooler. Some 318 manifolds also have plugs in one of the middle exhaust chambers. There should not be water there as this is an exhaust not water port.

The Dog House · Post by **The Dog House** » Sat Sep 29, 2012 5:47 pm

revitalizingtheoldgirl wrote:So it sounds like we're looking for 4 plugs then. Okay. No place for a bucket in the enigine compartment so we'll be connecting a length of hose to reach from the deck to the intake in order to get the antifreeze into her. Buckets on the exhaust to catch what's going through and a bucket under the hull drain to catch what we drain from the engine. Will 4 gallons of the pink stuff be enough? Want to make sure we're doing it right. Don't want to find out next spring we missed something when we winterized the block.

Five gallons should be enough, but I always use ten just to be safe. After running ten gallons of pink antifreeze through the engine, the antifreeze is definitely coming out of the exhaust. I also only get antifreeze coming out when I pull the engine and manifold plugs.

Don't forget the water system for the sinks. Empty the water tank as much as you can by running both taps. Then pour at least 2 gallons (I use 3 to be safe) into the water tank and run both taps. After pink antifreeze starts coming out of the taps, continue to leave the taps running to make sure the drain tubes are flushed with antifreeze. After a few minutes, you can turn off the taps. I also disconnect the tubes at the water pump and open the taps to drain the lines and water pump of the pink antifreeze. I used to leave the tubes connected, but was replacing the pump every two years. The pink antifreeze must damage the pump if it sits in the pump too long.

Big D · Post by **Big D** » Sat Sep 29, 2012 6:36 pm

Plumbing antifreeze swells rubber. Any rubber bellows typically found in fresh water pumps or engine raw water pump impellers will swell if it sits in antifreeze for extended periods.

larryeddington · Post by **larryeddington** » Sat Sep 29, 2012 9:22 pm

The riser is a cast piece at the end of the log manifold where the exhaust goes up then down to the outside of the boat. It is a cas iron piece and has a drain at its bottom.

The risers purpose is to insure water does not get sucked back into the eingine via the exhaust. As I said there are three drains on the 318, side of block each side, bottom of the exhaust manifold and at the bottom of the riser.

However if you cannot locate these or be sure to do it correctly, pay someone else to do it as they eat a mistake.

Jerry · Post by **Jerry** » Sun Sep 30, 2012 7:12 am

Big D wrote:Plumbing antifreeze swells rubber. Any rubber bellows typically found in fresh water pumps or engine raw water pump impellers will swell if it sits in antifreeze for extended periods.

I am glad that you said something Big D,
Not all pink is ok to use in engines. Most around here are not and are for plumbing only.
Read the jug.

prowlersfish · Post by **prowlersfish** » Sun Sep 30, 2012 8:06 am

I have used the pink made for RV plumming and never had a issue , Perhapps I need look into it . Are there diffrent types ? . Thankfully I don't winterize any more as I use the boat year round ( I use block heaters )

Jerry · Post by **Jerry** » Mon Oct 01, 2012 7:40 am

prowlersfish wrote:I have used the pink made for RV plumming and never had a issue , Perhapps I need look into it . Are there diffrent types ? . Thankfully I don't winterize any more as I use the boat year round ( I use block heaters )

Some pink is ethanol based and some is propylene based.
The ethanol based is not recommended for use in engines as it dries out rubber and causes corrosion.
I would love to be able to leave the boat in that water year round. I envy those of you that can.

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