This DIY describes how to start a 2007 CBF1000A Honda motorcycle when the engine has been flooded. The DIY is applicable for 2006 to 2010 models.
This procedure is in fact already described in the Owners Manual, but as some owners has unknowingly been hit by this problem, I thought it might be worth a few words.
Let me first explaing what a flooded engine is (you may jump down to the starting procedue if you already know this):
A flodded engine is an engine where too much fuel has got into the fuel inlet and into the cylinders. So much that the spark plugs are more or less shorted by droplets of fuel and the fuel mixture ratio is too rich for a proper burn process. The excess fuel can not contribute to the burning process as there is not enough oxygen for it. Instead it simply evaporates when the temperature rises. This cools down the entire burning process and thus reduces the pressure on the top of the piston.
Flooding mainly happens when the engine is very hot, or when a number of starting attempts has failed. The last situation often occurs when you attempt to start the engine up for the first time after winter hybernation.
The principle of this starting procedure is thus to use full throttle to get all this excess fuel blown out of the engine, so a new start attempt can be successfull.
Remark: I usually write up DIY articles in a neutral and non-personal style, but in this DIY I'll make an exception and keep the text almost identical to the post where it was first used.
Today - early february 2009 - I tried to wake up my CBF from 1.5 Mont's winter
hybernation (it hybernates indoor at around 10 degree C). The battery was fully charged
one week ago, but despite that, the engine did not start immediately as it usually does.
The first 4-5 attempts - each lasting 4-8 seconds failed. Fuel pump sound and all light indications seemed OK. There was some smell of fuel, but no sound of ignition.
I put on a charger to prevent deep discharge of the battery and waited a couple of minutes.
On the next couple of attempts I used full throttle to went the cylinders in case the engine was drowned. Still no sound of ignition (because at full throttle the electronic control module cuts off fuel supply - neat, thumbs up for Hondas engineers!).
On next attempt, I twisted the gas up a little and the engine fired up and rewed up
quickly, so I let the gas go, and it died again. OK - so there was life
Tried again a couple of times, playing with a little gas, and it fired up. I
kept it running with a little gas support for a few seconds, then I could let it idle
without gas support and everythin was back to normal.
Rode the bike for a couple of kms to let all mechanical parts become activated.
Back home I let the engine warm up further until the electrical fan kicked in.
Put the bike back indoor to sleep for the rest of February - shh ....
Now waiting for summer, killing time by reading and writing about mc-stuff.
... Fred
Finished.
© Copyright 2010 FireBladerDk - Last updated 2011-01-09