Topic: So THAT'S why Honda put a front fender there...

[tfrasca]

Hey guys,

I got stuck in the rain the other with no front fender on my 76' CB550. Rain water was coming off the front wheel, pretty much directly at the front of my engine, and onto my coils. Shortly before I got home, cylinder 2 cut out and I had to limp it home on three cylinders. 3, not 2- which I thought was interesting. I would think a short at the coils would have effected 2 cylinders.

Anyway, I pulled the tank, looked at all the wiring, and nothing was visually burnt, disconnected, etc. Still didn't want to fire on all three cylinders, and now cylinder 3 was intermittently cutting out as well. I pulled the plugs, and #2 was wet. I cranked it over a few times to try to dry out the cylinders, in case one was flooded. Put plugs back in, started it up and all 4 pipes got hot, but #2 and #3 were *slightly* less hot. I figured maybe things were slowly drying up and the rain-damaged coil was coming back to life.

I put the tank back on, rode around the block, and it alternated between running on 2 and 3 cylinders. It was ugly. Parked in the driveway, and I had gas coming out of the intake plenum drain, and one of the carb overflow hoses. I'm assuming that the gas overflow is from extreme flooding due to the plugs not firing while the cylinder is sucking in gas?

My questions are whether or not my coil could have been permanently damaged from water exposure (seems unlikely), and whether my gas overflow theory is plausible. I should say that before the 15 minute rain ride, the bike had been running beautifully for weeks, ridden every single day. Not a drop of gas overflow since I recently rebuilt and cleaned the carbs. I really doubt it's a carb issue. I also have a Dyna S ignition, but I don't suspect the rain hurt that either.

Any thoughts?

Thanks,
TF

[dave500]

you got an air compressor?try blowing it all dry,even the dyna,depending how wet the coils got the dyna could've suffered a bad feed back lump in its throat and failed?pull the caps and blow them inside and out aswell,you might've ruined a plug from being flooded aswell?they don't always clean up and run right again,you can burn them red hot with a propane torch if you want to try and clean it.

[tfrasca]

Damn, I hadn't thought about the Dyna failing from the short at the coils. That would suck. I'll get everything dried out when it stops raining and go from there.

Thanks, Dave.

[dave500]

you might need to check inside any bullet connectors,they sort of seal well but if moisture gets in it cant get out easy,open them up and dry them well,hope the dynas ok,most electronic ignitions wont handle no plugs fitted and being cranked over trying to spark nowhere,it backs up inside the unit,a fouled plug may cause the same #$%* happen,they might handle it they might not?

[seanbarney41]

Damn, I hadn't thought about the Dyna failing from the short at the coils. That would suck. I'll get everything dried out when it stops raining and go from there.

Thanks, Dave.

and get a fender!

[dave500]

fenders rule!did I just post that?

[seanbarney41]

lol      No!  Gibsons rule.


Fenders just keep the water where it should be.

[dave500]

fendersrule has left the building if you remember?very impressive.

[seanbarney41]

I start laughing just thinking about all that

[tfrasca]

Shoot. When I cranked it over, I had the blk/wht lead to the coils disconnected, but I guess the Dyna would still have had power to it. Fingers crossed I didn't fry it!

As for the fender, it's in the mail. I told myself I wouldn't ride until I mounted it. But I did...

Also, since I had gas overflowing from the intake, can I assume that my cylinders are full of gas now too?

TF

[ekpent]

Do you have pods or stock airbox ? I have had pods let me down in the major rain.  The gas leaking from the carb sounds to me like it may be a separate issue. Put a brand new plug in that cylinder you say was fouled also.
  If your overflow tubes are clean they should keep gas from going in the engine, if you were riding the bike with non working or fouled plugs those cylinders would has received a gas wash from unburnt fuel.

[tfrasca]

Stock air box. I'll put brand new plugs in it once I get it all dried up.

[dave500]

the cylinders wont actually be full of fuel per-say but some unburnt will be lurking,if they were full of fuel itll leak down overnight past the pistons and rings into the sump,i don't think you've contaminated your oil too much,if its close to an oil change due do it once its running right.

[tfrasca]

Oh good call on the oil change. After I sort out this problem, I need to replace the clutch, so I'll get the oil out of there no matter what.

I'm about to have a 60 mile daily commute, and I want to be able to take the bike at least a couple times a week. Gotta get it as reliable as a 38 year old bike can be!

TF

[dave500]

these are dead reliable!just kill any gremlins first,ill ride mine anywhere,if my wife would let me go!

[DH]

You might check for a sticking float as well. It could've started the whole process.
Just to verify..

[seanbarney41]

Oh good call on the oil change. After I sort out this problem, I need to replace the clutch, so I'll get the oil out of there no matter what.

I'm about to have a 60 mile daily commute, and I want to be able to take the bike at least a couple times a week. Gotta get it as reliable as a 38 year old bike can be!

TF

about 90,000 miles in 6 years on sohc4s, only stranded once because I broke my stator cover dumping, rode home from several other dumpings, only other breakdown was similar to yours, ignition system crap out induced limp for 60 miles...these are some tough, dependable bikes.  I have found very little need for tool kits and cell phones.

[tfrasca]

Oh good call on the oil change. After I sort out this problem, I need to replace the clutch, so I'll get the oil out of there no matter what.

I'm about to have a 60 mile daily commute, and I want to be able to take the bike at least a couple times a week. Gotta get it as reliable as a 38 year old bike can be!

TF

about 90,000 miles in 6 years on sohc4s, only stranded once because I broke my stator cover dumping, rode home from several other dumpings, only other breakdown was similar to yours, ignition system crap out induced limp for 60 miles...these are some tough, dependable bikes.  I have found very little need for tool kits and cell phones.

That's good to hear! I've been pleasantly surprised at how reliable it's been around town. I currently commute to school and work and the bike gets ridden every single day.

[seanbarney41]

Oh good call on the oil change. After I sort out this problem, I need to replace the clutch, so I'll get the oil out of there no matter what.

I'm about to have a 60 mile daily commute, and I want to be able to take the bike at least a couple times a week. Gotta get it as reliable as a 38 year old bike can be!

TF

about 90,000 miles in 6 years on sohc4s, only stranded once because I broke my stator cover dumping, rode home from several other dumpings, only other breakdown was similar to yours, ignition system crap out induced limp for 60 miles...these are some tough, dependable bikes.  I have found very little need for tool kits and cell phones.

That's good to hear! I've been pleasantly surprised at how reliable it's been around town. I currently commute to school and work and the bike gets ridden every single day.

that's the ticket.  These bikes love to be used....a lot.

[dave500]

just ask mooshie.

[alacrity]

I had mine crap out in the rain last week-- water got in under the aftermarket ignition cover.  The OEM gasket had actually shrunk over time and didn't seal up well.   New gasket on place now.  Should be good


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[dave500]

try running a bead of any silicone sealant neatly around the covers gasket seat,let it cure for an hour then fit it up,ive never liked paper gaskets there.

[faux fiddy]

I got into a situation where I was in a HUGE downpour an was eventually riding in a foot of water. I took off the points cover, dried all that out. Still nothing but dead, no run..

Not sure if it just didn't want to run or why it didn't, but pulled the float bowl screws out and drained them. Afrer that I turned the petcok back on and it started.  I figured what elese could it have been other than the carbs sucking water while wading through a huge puddle.

BTW I had fenders, and they rule.

[ekpent]

How do you make that "rule" do that.  You computer experts are slick   

[strynboen]

good vires on the coils is just as imp as fenders..