09' Honda BF115A Fuel help

will941s

Chief Petty Officer
Joined
Oct 1, 2007
Messages
540
Im working on this 2009 Honda BF115A for a friend of a friend. Motor came to me with head removed, talked to the owner and he was having surging/idle issues...sounded like a fuel issue. Head had some corrosion in the exhaust side so I replaced the head and all head parts. Everything is right in that department and to specs. Compression is about 205 even, but the fuel issue symptoms are still there. Imagine that.

So, at idle it's a little rough once its warm and IAC shuts down. You eeeeaaassseee on the gas, it'll go. Anything faster than that it dies. Only does this between dead idle and about 1,100 RPM's. Runs great above 1,100.

Starting at the tank, found a leak at the pick up...replaced it. Replaced fuel lines from tank, replaced water fuel seperator. Installed new primer bulb. Replaced VST outlet filter, cleaned screen on fuel pump. Replaced 10 micron entry filter. VST is clean. Lines are not showing signs of leaking on engine, no links. Connections are tight. Fuel pump test showed 2.7# out the low pressure pump. Replaced it, now showing about 3.4 at idle. Some improvement there.

Pulled fuel injectors, sprayed cleaner through them, and it seemed to improve some, but gradually went back to the way it was. Today I pulled #1 injector wire; shut off. Pull 2 and 3, barely any change. Pull 4, it changes a lot or shuts off.

Where do I go from here? Should I replace injectors? Cleaning them held open w 12V only does so much. Or has someone dealt with this before and can point me in the right direction? 1 and 4 ignition coil are the same right, as well as 2 and 3? Should I be looking there? Any help would be GREATLY appreciated!!!!!
 

hondam

Petty Officer 1st Class
Joined
Nov 21, 2013
Messages
213
99% with Hondas in general is fuel related so your probably on the right track. You probably should check the spark to make sure though.

Do you have access to an HDS (Honda Diagnostic System) or Dr. H? This will really help you narrow down the problem if that engine is compatible. I know the early 115A wasnt that late of a model might. You can tell by finding the red connector, If its a 2 wire connector then its not, if its a 4 wire connector then you might be able to use the diagnostic software.

Have you checked the fuel pressure to the rail? I think it should be about 40psi

Do not replace the injectors. I use a service called FuelInjectorMan.com. He is very good and reasonably priced. Gives you a computer printout of before and after for comparison.
 
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will941s

Chief Petty Officer
Joined
Oct 1, 2007
Messages
540
Thanks, I do not have any Honda diagnostic software. All I have are BRP and YDS. Thing is driving me crazy. I'll do a good spark check and see what it's doing, do you happen to know what gap it needs to jump? If spark is good, I'm going to tear down the fuel system again and probably send the injectors off to the company you referred. Looks like to check fuel pressure going to the rail itll use some type of metric screw in fitting, correct?
 

hondam

Petty Officer 1st Class
Joined
Nov 21, 2013
Messages
213
The plugs are set for much less but i leave my gap tester set at about 1/4" for everything. And yes you will need an adapter but its nothing special, comes with most kits.
 
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