OK, so for those of you who saw my u cooler post... let me redeem myself!
I have twin FWC 350 classics (small blocks) and had much more steam coming from the port engine after servicing this spring which included new impellers.
The temps on this motor were 7-9 degrees hotter than the other which was rock solid at 170. Temps were also erratic sometimes spiking and them dropping (never more than 190 though) So, with advice from here and reading all sorts of old posts I:
1) cleaned the strainers and verified good flow - no problems found
2) replaced the impeller again AND fixed a small drip on the cover plate with a new style foam (?) gasket from crusader - no change in motor
3) removed the end caps from the main heat exchanger and removed some zinc debris which resulted in a small improvement
4) carefully ran a brass rod through each of the 2 million water passages on the main heat exchanger - again a small improvement but not solved
5) replaced thermostat with new - no more spiking! ...but still steaming.
and finally...
6) replaced the u cooler with a new one and BINGO! - absolutely no more steam and rock solid on the temps. Yes, I could just have just acid cleaned but I have no good place to do so where the boat is and now I have a spare to keep at home, ready to go.
I hope by posting all this that it helps someone else going through the same issues. Thanks to everyone who has posted and particularly those who contributed their thoughts on the issues!
Lessons learned...
-work step wise from inexpensive to expensive and from simple to complex
-if you just did spring servicing or replaced a zinc and experience temp / steam issues check the coolers!
-don't give up!
Thanks again all!
JD
I have twin FWC 350 classics (small blocks) and had much more steam coming from the port engine after servicing this spring which included new impellers.
The temps on this motor were 7-9 degrees hotter than the other which was rock solid at 170. Temps were also erratic sometimes spiking and them dropping (never more than 190 though) So, with advice from here and reading all sorts of old posts I:
1) cleaned the strainers and verified good flow - no problems found
2) replaced the impeller again AND fixed a small drip on the cover plate with a new style foam (?) gasket from crusader - no change in motor
3) removed the end caps from the main heat exchanger and removed some zinc debris which resulted in a small improvement
4) carefully ran a brass rod through each of the 2 million water passages on the main heat exchanger - again a small improvement but not solved
5) replaced thermostat with new - no more spiking! ...but still steaming.
and finally...
6) replaced the u cooler with a new one and BINGO! - absolutely no more steam and rock solid on the temps. Yes, I could just have just acid cleaned but I have no good place to do so where the boat is and now I have a spare to keep at home, ready to go.
I hope by posting all this that it helps someone else going through the same issues. Thanks to everyone who has posted and particularly those who contributed their thoughts on the issues!
Lessons learned...
-work step wise from inexpensive to expensive and from simple to complex
-if you just did spring servicing or replaced a zinc and experience temp / steam issues check the coolers!
-don't give up!
Thanks again all!
JD
