Mercruiser 470 Froze over the winter

[slydog75]

Well, my father forgot to winterize our 470 over the winter and of course the fresh water that was left in the heat exchanger froze. So far I see that the aft end cap on the exchanger appears to be bowed out and leaking. What other damage can I expect this to have caused?

 

[Don S]

Re: Mercruiser 470 Froze over the winter

If the anti freeze in the rest of the cooling system was ok for the temps you had, then the heat exchanger and possibly the riser should be your only problems.
Take the riser off and inspect for cracks (inside and out).
Remove the heat exchanger and pressurize the antifreeze side of the HE, and see if it holds pressure. A radiator repair shop may be able to repair it and check it out for you if you don't have the stuff to do the job.

 

[slydog75]

Re: Mercruiser 470 Froze over the winter

I'm suspect the antifreeze in the closed cooling system side should be fine. Hopefully parts for the heat exchanger aren't as hard to find as a new valve cover was!

 

[q5ka]

Re: Mercruiser 470 Froze over the winter

While you are getting it (the heat exchanger and risers) checked out, watch EBay. Heat exchangers and risers pop up there often enough that you may be able to replace if yours are in real bad shape. Check those risers for cracks. If the HE was full, there could have been water in the risers also. Check your oil and plugs also. If your riser cracked, you could have gotten water in the exhaust manifold which means water in a cylinder. Just trying to give you worst case. If oil is milky, you have bigger problems. If plugs wet, you could also have bigger problems. Good luck.

 

[CTJeff]

Re: Mercruiser 470 Froze over the winter

If you run out of gas, did your Dad forget to put gas in it?
Did your Dad forget to have fun on it all summer too?
I could go on, but I hope you get the message by now.
If you haven't, show your Dad your posts.

 

[slydog75]

Re: Mercruiser 470 Froze over the winter

If you run out of gas, did your Dad forget to put gas in it?
Did your Dad forget to have fun on it all summer too?
I could go on, but I hope you get the message by now.
If you haven't, show your Dad your posts.

Easy there. We have joint owner ship of this boat, but he's retired and I travel all over this God Blessed Country for work. Before I left on a 3 week business trip in early october I asked him if he'd take care of it and he said he would. It skipped my mind after that until two weeks ago, .. unfortunately it skipped his too.

 

[Bondo]

Re: Mercruiser 470 Froze over the winter

It skipped my mind after that until two weeks ago, .. unfortunately it skipped his too.

Ayuh,... But,... Dad is older, He's got an Excuse,....

 

[stonyloam]

Re: Mercruiser 470 Froze over the winter

Check Mercruiser manual #8 (470 cooling system, adults only Mercruiser manuals) page 6A-7, they talk about your exact situation. When we pull our boat out for the winter, as soon as it is on the trailer, we pull the transom plug and the fresh water (aft) plug on the exchanger and let it drain right then and there, 90% of winterization done by the time we get home. Just be thankful you had one of those crappy old 470's and not a "good" 4.3.

 

[Don S]

Re: Mercruiser 470 Froze over the winter

Ayuh,... But,... Dad is older, He's got an Excuse,....

Yeah, but if Dad is anything like me, he first has to remember what that excuse is, if he remembers what he forgot to do, but then again it doesn't really matter what oil you have in that engine as long as you change it when ever the drive is up and....... What were we talking about again

 

[slydog75]

Re: Mercruiser 470 Froze over the winter

yeah, but if dad is anything like me, he first has to remember what that excuse is, if he remembers what he forgot to do, but then again it doesn't really matter what oil you have in that engine as long as you change it when ever the drive is up and....... What were we talking about again :d

rofl

 

[slydog75]

Re: Mercruiser 470 Froze over the winter

Check Mercruiser manual #8 (470 cooling system, adults only Mercruiser manuals) page 6A-7, they talk about your exact situation. When we pull our boat out for the winter, as soon as it is on the trailer, we pull the transom plug and the fresh water (aft) plug on the exchanger and let it drain right then and there, 90% of winterization done by the time we get home. Just be thankful you had one of those crappy old 470's and not a "good" 4.3.

Nice, tip. Thanks!

 

[CTJeff]

Re: Mercruiser 470 Froze over the winter

Sly-
Watch it, I got the old guys back. I would agree with the posts above. I do the same with my 470, I would add, to take off the return hose to the exchanger and blow it out with a compresser (if you have one) you can see and hear fresh water exiting the outdrive intakes. Or have your Dad to it.
Happy Boating
Jeff

 

[rjwoodrome]

Re: Mercruiser 470 Froze over the winter

I've seen it happen before, get a new end cap and gasket, you should be fine. although thae a look at the exaust riser as before mentioned..

 

[Don S]

Re: Mercruiser 470 Froze over the winter

I've seen it happen before, get a new end cap and gasket, you should be fine.

Just remember one thing guys. It's a 470. Overheats and 470's do not get along. If the freeze did damage any of the tubes in the heat exchanger and the coolant is lost he overheats while on plane, you end up changing head gaskets or worse.
That is why I said pressure test it, and not just throw an end cap on and hope for the best......... I did say that didn't I