Help with Honda Aero 50 Starting Difficulties?

Midwinter · Post by **Midwinter** » Fri Apr 20, 2007 2:48 pm

Hi all. I know it's an Aero, but I thought I'd ask for advice here.

I picked up a 1985 Aero from a friend. It has, apparently, always had difficulty starting (so much so that someone drilled a hole through the plastic shell, the air filter cover, and the filter so they could spray starter fluid into the carb!). If it has been left idle for several hours, or if it is particularly cold, the thing just won't start without a squirt of starter fluid. Once it starts, though, it runs like a top.

I've replaced the vacuum/fuel lines leading from the petcock to the carb. I've cleaned the carb (including the jet, which I thought surely was the problem). I've adjusted the carb to proper settings.

This didn't fix it.

Yesterday afternoon, I pulled the petcock off and squirted carb cleaner into it.

Still wouldn't start.

Last night, I squirted WD40 into the petcock.

Wouldn't start this morning.

It *tries* to start, initially, which I suspect is a little bit of fuel left in the line and carb, but then it dies.

Am I right in thinking that all signs point to the petcock having gone bad? Are there any potential troubleshooting tips anyone might have? I have no idea how to check the petcock to see if it's functioning.

Thanks in advance.

HuskieMobileMan · Post by **HuskieMobileMan** » Fri Apr 20, 2007 7:34 pm

The electric choke is probably bad.

Midwinter · Post by **Midwinter** » Fri Apr 20, 2007 10:18 pm

HuskieMobileMan wrote:The electric choke is probably bad.

Any idea what the choke costs? I assume $50, since it seems that every part on this scooter costs $50

Also...is this a part my Honda shop might have in stock?

Post by **noiseguy** » Sat Apr 21, 2007 11:19 am

D/L the service manuals from this site on your scoot. There's a procedure to test the bystarter before you spend the money to buy a new one.

Midwinter · Post by **Midwinter** » Sat Apr 21, 2007 2:41 pm

Well I'll be. Had no idea that that manual was there!

Took the carb apart again this morning, cleaned it (again), sprayed some WD40 into the moving bits of the choke, and the thing started right up.

I'm going to let it sit for a few hours and see if it still starts without difficulty.

Post by **noiseguy** » Sat Apr 21, 2007 10:17 pm

The passages around the bystarter sometimes clog, which keeps it from working.

Midwinter · Post by **Midwinter** » Sun Apr 22, 2007 8:00 pm

noiseguy wrote:The passages around the bystarter sometimes clog, which keeps it from working.

I've taken the carb apart several times and have given it a good going over with carb cleaner. I know the carb is getting gas. I pulled the bystarter and checked the resistance, which was where it should be. I've hosed down the inside of it with WD40 and carb cleaner. The needle seems to move OK. By "passages," do you mean the ones in the carb or in the bystarter itself?

I'm replacing the coil and plug tomorrow to see if that's the problem.

Is it possible that my exhaust port is clogged? The thing only has 500+ miles on it.

Thanks for all the responses.

Post by **noiseguy** » Sun Apr 22, 2007 10:22 pm

The exh port could be plugged, but not likely.

Does it cold start now?

All the mods done to the aircleaner may actually be making it harder to start. Doing that to a Spree would prevent it from starting.

Midwinter · Post by **Midwinter** » Mon Apr 23, 2007 12:08 am

noiseguy wrote:The exh port could be plugged, but not likely.

Does it cold start now?

All the mods done to the aircleaner may actually be making it harder to start. Doing that to a Spree would prevent it from starting.

I took the muffler off and looked at the exhaust port. It's got some sludge, but it wasn't plugged. Once I put it all back together, it started right up after being idle for about 18 hours.

Go figure.

Just tried to crank it after letting it sit idle for 8 hours. It cranked up on the first try, idled for a few seconds, and petered out. Then it would start with difficulty, idle for a few seconds, and die. I'm sure if I stayed at it, it would start up and run fine.

Post by **noiseguy** » Mon Apr 23, 2007 9:16 am

Play with your idle settings... will it keep running from cold if you goose the throttle?

Midwinter · Post by **Midwinter** » Mon Apr 23, 2007 11:11 am

noiseguy wrote:Play with your idle settings... will it keep running from cold if you goose the throttle?

If I can get it to turn over and stay running for more than 5 seconds, yes. I also have it idling a *little* high.

Midwinter · Post by **Midwinter** » Mon Apr 23, 2007 7:55 pm

noiseguy wrote:Play with your idle settings... will it keep running from cold if you goose the throttle?

OK. With a new coil and plug, it cranked right up after being idle all night and day. Old plug was black and sludgy. Took it for a spin and it died while idling, but otherwise ran fine. Cranks up with a little goosing of the throttle, though.

I think all I need to do is get the idle set right and I'm good to go.

Thanks!

Midwinter · Post by **Midwinter** » Thu Apr 26, 2007 1:02 pm

Well this little thing is turning out to be a mystery.

Yesterday morning, the thing would not start, even with starter fluid. Then, after sitting idle for 8.5 hours, it cranked on the first hit of the starter.

So. Starts in the afternoons but not in the mornings.

Carb is running great (after I found out that the fuel jet screw was waaaay loose). Idles fine now. Runs fine now.

But won't crank in the morning.

The Honda shop here said it sounded like a compression issue (with only 590 miles?), but before I even consider taking the engine apart (although I might check the head gasket this weekend), I wondered if anyone had any alternate theories. Water in the tank, maybe?

Post by **noiseguy** » Thu Apr 26, 2007 9:56 pm

Check the compression yourself with a tester... I doubt it's a compression issue. I think it's a carb issue.

Midwinter · Post by **Midwinter** » Thu Apr 26, 2007 11:03 pm

noiseguy wrote:Check the compression yourself with a tester... I doubt it's a compression issue. I think it's a carb issue.

That's my next step.

Added an in-line fuel filter today, and in the process learned a couple of things:

1) This scooter has had a piece of vacuum line instead of fuel line for the entire time I've had it.

2) If you put the gasket on between the carb and the mount, it doesn't run well.

Been running fine since I made these two mods. I'll know more tomorrow morning when I try to crank it.