Hot Nautique

[Crawdad2]

I have a 1994 Nautique with a PCM 351 Ford in it. It ran hot so I rebuilt the raw waterpump and it still runs hot. The recirculating pump on the block looks like it's new. Raw water filter is clean. Can,t figure out why I can't keep it cool. Any ideas ??

 

[Bondo]

Re: Hot Nautique

I have a 1994 Nautique with a PCM 351 Ford in it. It ran hot so I rebuilt the raw waterpump and it still runs hot. The recirculating pump on the block looks like it's new. Raw water filter is clean. Can,t figure out why I can't keep it cool. Any ideas ??

Ayuh,... Welcome Aboard,... Is the line from the sea-**** to the pump clear, 'n vacuum leak free,..??

Have ya pulled any water lines to See the flows yer gettin',..??

Are the manifolds, 'n Risers clear, 'n obstruction free,..??

Ya gotta get the water Out, as well as In,...

 

[salty87]

Re: Hot Nautique

it's not uncommon to find parts of old impellers downstream of the pump like at the thermostat. they can restrict flow.

to verify waterflow you can get a long section of intake hose, connect it to the transmission cooler and stick the end in a 5 gal bucket full of water. an idling engine should suck the bucket dry fairly quickly. this will also test the pump's ability to draw water. if you use a normal hose to supply water the household pressure can hide vacuum problems like Bond-o mentioned.

another possibility, depending on where the boat has been, is clogged risers/manifolds. a handheld IR temp gun is handy for finding hot spots. you can also visually inspect the passages by removing. you'll need new gaskets to reinstall.