Engine room ventilation SM2000 2001


svperegrinus <no_reply@...>
 

Hello,

Testing engine room ventilation today with shore power unplugged, I found the following:

1/ Main Yanmar engine ON, Onan Cummins Generator OFF:
(a) A blower pumps air from somewhere port side and ends in a gray PVC tube that blows air into the transmission area of the Yanmar engine
(b) An exhaust air pump pushes air out of the engine room via the air exhaust outlet port side that sits outboard of the winches

2/ Onan Cummins Generator ON, Main Yanmar OFF:
(a) The blower remains OFF. No airflow from the gray PVC tube
(b) The exhaust air pump pushes air out of the engine room via the air exhaust outlet port side that sits outboard of the winches

Questions:

i. Why the difference? does yours also work differently depending on which engine is being used?

ii. Under scenario 2/ above, there is a decent air volume coming out of the exhaust outlet port... but where is the air feeding into the room? Air cannot be pushed out unless it is being fed somewhere!

Thank you in advance for your comments,


F + O
s/v Peregrinus
#350, November 2001


svperegrinus <no_reply@...>
 

Actually, full explanations are in the manual, including the fact the Yanmar does get air blown into the engine room, whereas the Onan Cummins has to do with air naturally aspirated into the room.

--- In amelyachtowners@..., svperegrinus wrote:

Hello,

Testing engine room ventilation today with shore power unplugged, I found the following:

1/ Main Yanmar engine ON, Onan Cummins Generator OFF:
(a) A blower pumps air from somewhere port side and ends in a gray PVC tube that blows air into the transmission area of the Yanmar engine
(b) An exhaust air pump pushes air out of the engine room via the air exhaust outlet port side that sits outboard of the winches

2/ Onan Cummins Generator ON, Main Yanmar OFF:
(a) The blower remains OFF. No airflow from the gray PVC tube
(b) The exhaust air pump pushes air out of the engine room via the air exhaust outlet port side that sits outboard of the winches

Questions:

i. Why the difference? does yours also work differently depending on which engine is being used?

ii. Under scenario 2/ above, there is a decent air volume coming out of the exhaust outlet port... but where is the air feeding into the room? Air cannot be pushed out unless it is being fed somewhere!

Thank you in advance for your comments,


F + O
s/v Peregrinus
#350, November 2001


Judy and Bill aboard SV BeBe <yahoogroups@...>
 

On hull 387 there is a 230 volt fan located above the generator. This fan automatically energizes when the generator is running. On 387, the output of this fan is less than the output of the 12 volt Yanmar ventilation fan.

We installed a 24VDC fan which blows on the HP 160 liter water maker pump when the water maker is turned ON.

Bill
BeBe, SM2k, #387

--- In amelyachtowners@..., svperegrinus wrote:

Actually, full explanations are in the manual, including the fact the Yanmar does get air blown into the engine room, whereas the Onan Cummins has to do with air naturally aspirated into the room.



--- In amelyachtowners@..., svperegrinus wrote:

Hello,

Testing engine room ventilation today with shore power unplugged, I found the following:

1/ Main Yanmar engine ON, Onan Cummins Generator OFF:
(a) A blower pumps air from somewhere port side and ends in a gray PVC tube that blows air into the transmission area of the Yanmar engine
(b) An exhaust air pump pushes air out of the engine room via the air exhaust outlet port side that sits outboard of the winches

2/ Onan Cummins Generator ON, Main Yanmar OFF:
(a) The blower remains OFF. No airflow from the gray PVC tube
(b) The exhaust air pump pushes air out of the engine room via the air exhaust outlet port side that sits outboard of the winches

Questions:

i. Why the difference? does yours also work differently depending on which engine is being used?

ii. Under scenario 2/ above, there is a decent air volume coming out of the exhaust outlet port... but where is the air feeding into the room? Air cannot be pushed out unless it is being fed somewhere!

Thank you in advance for your comments,


F + O
s/v Peregrinus
#350, November 2001