Still cleaning out raw water cooling system from broken impeller

rasbury · April 2015

I started a new discussion because the previous thread was question I marked answered so figured I needed to start over?

I opened up the starboard side removing the end cap. I now see the tubes are set into another "end plate" 2" or so back so now I see why I don't have coolant all over so I'm now good with that. What I still am not understanding is how the water gets into the tubes....the inlet to the exchanger is not routed to that space between the end cap and the other "end plate" where the tubes start but a little behind that.....there is a hose coming out of that space but goes to the starboard side riser I guess it is...there was nothing of any sign of impeller pcs. in that space but I don't see how any would get there in the first place! I'm thinking I should have pulled off the hose where it goes into the exchanger as that is where it would collect stuff? I have the manual but I'm just not getting it. I'll go look again at the manual....sorry to be so thick on this!

rasbury · April 2015

ok guys, no one told me which end to open up- I thought in pump pumped the water to the exchanger on the port side of the exchanger which is actually the exit side.....duh, sorry. I opened the wrong end! I' m almost glad I don't have to face anyone...ok, I see from the manual why I was confused and you can't exactly sit down in front of the motor and see everything...anyway, pulled the port side off and found one little piece- it looks very clean, no corrosion...but still concerned that there is stuff stuck somewhere...is there somewhere in between the pump and the exchanger where something could stop up? Also, do the gaskets on the caps need to be replaced? Is there a sealant for those? Manual sounds like yes to both but there was no residue of a gasket material. Should I try somehow to back flush? Not much room in there to get a hose. The impeller is so chewed up there is no way to know what might be missing-not a lot but I am sure some....dang

raybo3 · May 2015

Open both ends and take a water hose and just flush the tubes. If you think the tubes are still plugged you can use a coat hanger and run it inside the tubed. Usually the water takes care of the problem. Remember very little debris can cause a problem.......

Handymans342 · May 2015

I would be hesitant to use any sharp metal thing. They make a nice nylon brush on an aluminum rod just for this purpose.

rasbury · May 2015

what about the gaskets, should they be replaced? Use Perfect Seal sealant? It did not look like anything had been used. I will see If I can find some sort of brush to go through the tubes> Should I try to back flush from the exchanger back? There is still water in the line going back and I'd think there could be some debris still in there that did not make it to the exchanger yet....

Handymans342 · May 2015

You could turn over the motor but dont start it and use the flow from the pump to flush out any debris in the hose. Always good to use a new gasket but if the old one is still flexible you could reuse it or save for a spare

JC290 · May 2015

I would flush from exchanger back won't hurt as far as a gasket in not sure

LaRea · May 2015

If the gasket isn't torn, re-use with no sealant on the gasket. Just check it after the first time you run the engine to make sure it's not dripping.

rasbury · May 2015

that's what I was thinking....The gaskets are intact and while a lot of water moves through the exchanger, not sure how much pressure is actually there....I was surprised how easy the bolts broke loose when I took them off. I will take off the hose to the exchanger and put a hose in it and get some real pressure going and blow that out. Hopefully the new impeller kit arrives today so I can put that back together tonight and in the boat in the am- the weather here in FL is absolutely perfect this weekend......figures!

rasbury · May 2015

went by the Merc dealer and they did not have the parts...they advised looking at the condition of the gasket I'd probably be ok to re install and they offered to order them if needed so we will see what happens with that and hope my new impeller arrives today! Will up date, I sure have learned a lot about this boat in a short amount of time!!!!

rasbury · May 2015

all blown out and re installed water pump...which with the wear plate requires a gasket material so will let that set up tonight and hit the switch in the am, thx for the help.

Handymans342 · May 2015

OK Ras, no more problems from you this year please

JC290 · May 2015

Splash that thing and enjoy

rasbury · May 2015

Handy, only way I see that happening is to park it.....I did fire it up, it squeaked for about a second and a half and then the water was flowing- I should have put more lube in it, hope it didn't hurt anything...heading for the river!