locked Re: Engine Room Exhaust Fan / Blower - lessons learnt #lessons


Hello Bill,


Are you sure this email is for me?

I do not encounter a temperature problem with my D3 110, and I do not believe I have asked any question on this subject on the sites.


Your answer concerning the engine temperature is as usual very relevant.




José ORION A54


De : main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> De la part de CW Bill Rouse
Envoyé : jeudi 2 septembre 2021 23:43
À : main@AmelYachtOwners.groups.io Notification <main@amelyachtowners.groups.io>
Objet : [Special] Re: [AmelYachtOwners] Engine Room Exhaust Fan / Blower - lessons learnt #lessons




80C or 176 is the normal operating temperature and if the cooling system is working correctly, the temperature should not increase more than 5-8% even at the highest RPM. When you measure 80C on the oil filter, you should measure 50C at the exhaust elbow immediately after the water inlet to the elbow. If it is higher, there is a problem that may be one of the following.


Possible Causes of Overheating:
1. Restricted seawater flow anywhere in the pathway beginning with the seawater entry into the sea chest to the seawater and exhaust exit through the hull. 

a. Sea Chest restriction

b. Hose restriction or kink

c. Restriction at the input to the in-line transmission oil cooler, if equipped

d. Failing seawater pump and/or failing seawater impeller

e. Restricted Exhaust Elbow

2. Restricted Coolant water flow

a. Failing coolant water pump

b. Failing Pressure Cap (should be replaced every 2 years)

c. Failing and/or clogged Heat Exchanger

3. Incorrect coolant ratio, but this is usually not a major contributor but will contribute somewhat.
4. Incorrect V-Belt tensioning with the V-Belt turning the coolant water pump
5. Failing Coolant Thermostat (not opening completely)
6. Other engine issues


Do not think that you can measure enough water flow by observing the seawater and exhaust exiting the boat. It will fool you.



CW Bill Rouse Amel Owners Yacht School

Address: 720 Winnie, Galveston Island, Texas 77550 


View My Training Calendar


On Thu, Sep 2, 2021 at 1:40 PM Jose Venegas via groups.io <josegvenegas=icloud.com@groups.io> wrote:

David, you may have something here.  I have noticed randomly occurring increases of engine temperature up to 220F when running the engine above 2000 RPM.  However the temperature does not seem to drop after opening the engine-room  door  and have not been able to measure any temp in the engine higher the 176F with an infrared thermometer.  

Any thoughts?

Jose Venegas
Ipanema SM 278 

currently in Shelterbay PANAMA 

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