Sand in Block

[Rinker 243 ATL]

2000 Mercruiser 5.0 was stuck in very shallow water at the end of the last usage. When I winterized the boat I noticed the Port Side Exhaust was running abnormally hot. Pulled the water pump and did not see any sand in the block, but with a hose flush there was a significant amount of sand in both sides of the block. Any suggestions on the best way to totally flush the block?
I tried a quick run on the water, and the overheating on the Port side of the engine was still there. Pulled the exhaust elbow and did not see any concerns. thinking about either poping the "freeze" plug and or pulling the exhaust manifold to see if there is blockage.
Anyone with experience with the sand in the block?
Thanks

 

[HT32BSX115]

Re: Sand in Block

Anyone with experience with the sand in the block?
Thanks

It's not uncommon to get sand in the block if you run the drive into sand at slow speed etc....

Running the engine wouldn't flush a lot of sand since the thermostat doen't open very much and the circulating pump doesn't move water all that rapidly thru the block anyway.....

Sand ingestion may cause abnormally high wear in your raw water pump and if enough was allowed in the engine, could cause overheats I suppose if enough was left in the block.

I was able to remove a fair amount of sand and other debris from my 454 by removing the circulating pump and all the core plugs.....then flushing the block extensively through each of the openings.

If you suspect sand in the exhaust manifolds, you can remove them and flush each one individually. With all the core plugs out, I was actually able to see in there.

Enough sand in the block would probably reduce cooling effectiveness and could prevent you from completely draining the block for freeze protection.

I had my engine on a stand when I did it so it was pretty easy.

Iif you do remove the core plugs, replace them with new brass ones.


Regards,


Rick

 

[backyard mechanic]

Re: Sand in Block

Back a number of years ago elbows and manifolds had large brass plugs in them. We'd back flow those with water from a hose to get the sand out. Pretty effective. I have to believe the same thing will work today.

I understand that today there are smaller drain plugs but the hose from the exchanger (or engine WP) will come off so you can flush it out that way. If there is a way to reverse flush the water it may work. I'd make bets there is a way to get from hose fitting to 1/4 pipe plug or whatever it takes...

It's been years since I've done that but there's a suggestion for ya. If it works, great! Persistence pays off in ridding your block and manifolds of the sand. Cooler engines are better engines.

 

[Rinker 243 ATL]

Re: Sand in Block

Thanks for the information, really confirms what I thought. The biggest concern I have is one I knock out the Freeze Plugs and flush out the block - which I must do, it is going to be very difficult to get tools in the bilge to replace the plugs.

Any suggestions on how to replace the Freeze Plugs - is there a special tool for replacing the plugs?

The only other though is to take the water pump off again and use high pressure water to flush the block - one side at a time. Not sure how the water flows though the block.

Not trying to do this half way, but very concerned with the success of replacing the freeze plugs while half way upside down in a tight bilge.

Thanks

 

[flyer4ever]

Re: Sand in Block

A hundred years ago when I was young. We used to replace a freeze plug with a rubber one that you tightened down with a wrench. I just googled it and they still sell them. Very easy to replace and they work very well. Ernie

 

[Rinker 243 ATL]

Re: Sand in Block

Had a quick thought about that one, but made me nervous with a semi permanent fix on the freeze plugs, but on second thought that is probably the best solutions. Once I bang my knuckles trying to put in new brass freeze plugs and say all kinds of nice things about the job.

Guess I could add some Permitex Gasket Maker around the rubber - bolt in plugs and then check every 30 days. My life if boating on Lake Lanier and i aways carry tools - and will carry a spare freeze plug as well.

Beats the heck out of burning an engine from overheating due to poor circulation.


Thanks

 

[flyer4ever]

Re: Sand in Block

Actually they say not to use any type of permatex at all. The other good thing about them is, If you ever run in the shallows again, it will be a lot easier to pull them out and reuse them again. I would not ever hesitate to use these things. They simply work. Good luck. Ernie

 

[Alumarine]

Re: Sand in Block

Millions of cars have had block heaters installed and they don't fall out or leak as a rule.

I wouldn't worry about the rubber ones.