I drain alot of water out then fire it up and run 5 gallons through it been doing it for years and lots of customers boats as well.

For five years I've been using a five gal bucket with a sump pump in the bottom hooked on to ears. No prob here in Missouri. My buddy's all do the same. I will pull the plugs this year see if any junk runs out I didn't do it last year and the year before I had some grit run out of the manifolds.

I always get sand in the drain plugs of the manifolds or the block seeing how i run the Wisconsin River.

When i had my 454 in the baja, i did drain all the hoses, and plugs. And do the remove the thermostat cover method and just fill the engine. That seemed to work fine too.....

i cant reach my drain plugs so i duckt tape off my low water pick ups and run a hose from my fresh water flush sys. to a 5 gal. bucket with pure anifreeze on to of my manifold. i run 2 buckets threw each motor because i cant drain the water in there, i also remove the temostats so that there is no issue with wether or not they have opened and it is just running out the exahust. i have 2000 502 mag mpi's

As I see some others on this site do also.

Here's what I've posted on various sites over the years.

It's that time of year, so this is very appropriate and super helpful. I made this a few years ago also, and absolutely love it. Friends borrow it - okay, make me do it - to there boats, it works so well.

Super cheap and ultra effective !

OK. Here's my engine flush tool.

Parts needed:

1) 5 Gal or bigger Bucket - one with handle is much easier
2) Garden hose
3) Perko thru hull plastic fitting - 3/4" barbed fitting
4) hose clamp
5) sealant

Drill a 1" hole thru bottom of bucket in flat area. Usually middle has a ridge from manufacturing so don't do it here. Go off to the side where nice and flat.

Slide Perko fitting thru to make sure it will totally slide thru. When okay - remove and apply sealer to bottom edge of the outlet (rounded part) and insert fitting so that the hose fitting section sticks outside the bucket. Install fittings nut tightly and let dry.

Grab 3/4" garden hose and cut off female fitting. This side of the hose will slip over the male barbed section of the Perko fitting outside/bottom of bucket.

Find a place where suitable to hang bucket. You can see where I have it. I can see level while in boat with boat running. Can also fill it from ground so that none will be spilled inside boat. A bocket with hanger makes positioning very handy.

Install male section of hose on Muffs. Cut garden hose to length. Remember not to cut off garden hoses male outlet!

Note: Have bucket higher than the outdrive so that it is gravity fed. This will make sure there are no priming / drawing issues - especially on the weak draw of Alpha pumps. I have it so that it is actually higher than the engines coolant passages so that it will feed to the top of the engine itself, just in case.

Anyway - you get the idea. Take a look at the pic. It's simple, way cheap, and makes it a heck of a lot easier than most other methods.

If its a Bravo style just pull the hose off the gimble inside of the boat and stick it in a 5 gallon bucket. I use a piece of PVC and an elbow and connect the hose to that. But it only really works on a single, twins would be a *****!

Chances are if you have water mixed in with the gearlube, you've already got problems!!