| Author |
Message |
    
Chris Brunson
New member
Username: brunsonc
Post Number: 3
Registered: 10-2009
| | Posted on Wednesday, October 28, 2009 - 05:31 pm: | 
|
Just got done replacing old waterpump and cleaning the carbs and the motor is running awesome. But, I'm pretty sure that some of the old impeller is still in the cooling system because every now and again the pee stream gets really weak. My question is, how exactly do you do a backflush to get this stuff out? Do I need to remove the lower unit and where do I back flush from. Thanks, any tips are appreciated. |
mike
Advanced Member
Username: hondadude
Post Number: 218
Registered: 03-2009
| | Posted on Wednesday, October 28, 2009 - 11:06 pm: |
|
I would recommend pulling the lower unit off and checking first under the water pump for any impeller parts that may have fallen in there between the intake and the water pump if you have not already checked there. That is normally where many pieces go. The pieces could be just partially blocking the intake at the water pump. Remove the intake grates and backflush from the water pump down.
While the lower unit is off, pull the thermostat (rear port top of the engine...you have to remove the timing belt cover to get to it) backflush with a garden hose from the thermostat. Check how the water is coming out the pickup tube and how it is coming out the telltail indicator. If the telltail is questionable, remove the telltail hose from the connector that goes through the cowling. It may be just a little piece in the telltail hose at the fitting. Hopefully, it is small enough to come out the hose or it is stuck in the cowling fitting. Make sure the fitting is clear (a paper clip works good)
Also check for debris in the thermostat while you are at it. |
Chris galati
Member
Username: constablechris
Post Number: 16
Registered: 06-2009
| | Posted on Friday, October 30, 2009 - 08:22 am: |
|
Also a problem I had was I had not done up the bolts tight enough when i replaced my impeller. Not being done up tight enough let air in so sort of caused an airloc esp as I was moving along at pace (water pump was prett much out of the water. After I sat at idle for a few minutes and tried to clear what I thought was a blocked tell tail it would piss out again.
Just a thought, cause I pulled all mine apart only to find nothing worked till I snugged the bolts down |
Chris Brunson
Member
Username: brunsonc
Post Number: 4
Registered: 10-2009
| | Posted on Friday, October 30, 2009 - 09:45 am: |
|
I backflushed from the thermostat last night and only got one pea sized piece of debris to flush out. The water was flowing fine thru the pickup tube, but was weak out of the telltail. I checked the hose and the connector at the cowling and they were both clear.....I'm guessing my next step is to remove the nipple from the motor that the pee hose connects to and try to flush whatever is in there out...what do you guys think??? |
mike
Advanced Member
Username: hondadude
Post Number: 220
Registered: 03-2009
| | Posted on Friday, October 30, 2009 - 10:43 am: |
|
Try your backflush again and put your finger over the pickup tube to block its flow out there...that will create more pressure to the telltale area. More than likely, the flow will improve out the telltale.
If you have a source of compressed air...blowing it back through the telltale hose may help dislodge whatever may be in there if the flow does not improve when you plug the pickup with your finger. |
scott craven
Member
Username: dark_star
Post Number: 26
Registered: 09-2008
| | Posted on Friday, October 30, 2009 - 11:41 am: |
|
I have a BF50A that has been a great motor aside from the fact that the telltale is always getting plugged.
Recently had the lower unit removed and water pump serviced with new impeller thinking that would solve the problem.
No such luck.
I usually disconnect the water tube from the plastic fitting and poke a wire into the tube through the nipple into the engine.
Most often i can clear it, but sometimes it's a job.
I think the water passages are small enough that any small particles sucked up will lodge and restrict flow.
I know others that have had the same problem. |
me opie
New member
Username: meopie
Post Number: 2
Registered: 12-2009
| | Posted on Sunday, March 14, 2010 - 02:01 pm: |
|
See this link for larger pee hole http://www.macgregorsailors.com/forum/viewtopic.php?f=7&t=12568&hilit=indicator |
