Running like it is running out of gas! update

Chad in Michigan · June 04, 2011, 10:45:57 PM

inside the petcock is another rubber diaphram that can foul and fail. that could still be the problem, or sediment in your tank. i would definately replace that vacuum line. try finding 1/8" ( i think) line. replacement windsheild washer tubing works also, that is usually easy to find at most auto parts stores.

Magnum Magna · June 12, 2011, 03:06:47 PM

Changed the plugs and vacuum line to the auto-petcock. Lost some coolant changing the front plugs. I will try going to the Honda shop in Farmers Branch Monday to get more coolant. Or will any premix coolant work?

I don't think the plugs looked bad at all for 30K plus miles. Considering on my 250 Kawasaki I had to scrape off carbon build up every 1000 mile for them to keep running. Under the seat it had a holder to hold two extra plugs and trust me I used them.

Chad in Michigan · June 12, 2011, 04:01:39 PM

Quote from: Magnum Magna on June 12, 2011, 03:06:47 PM
Changed the plugs and vacuum line to the auto-petcock. Lost some coolant changing the front plugs. I will try going to the Honda shop in Farmers Branch Monday to get more coolant. Or will any premix coolant work?

I don't think the plugs looked bad at all for 30K plus miles. Considering on my 250 Kawasaki I had to scrape off carbon build up every 1000 mile for them to keep running. Under the seat it had a holder to hold two extra plugs and trust me I used them.

you dont have to disconnect the radiator for the front plugs. you can slide it out of the way next time

Magnum Magna · June 12, 2011, 04:11:30 PM

It was time to change it anyway. I think it is every two years and it has been three years.
And that is my story and sticking to it.

Jerry G Turner · June 12, 2011, 05:47:18 PM

If you use the spark plug socket that comes with the tool kit you don't
have to touch the radiator.

roboto65 · June 12, 2011, 05:59:40 PM

If you pull the carbs you really do not have to touch the radiator.

Magnum Magna · June 12, 2011, 07:38:58 PM

Quote from: Jerry G Turner on June 12, 2011, 05:47:18 PM
If you use the spark plug socket that comes with the tool kit you don't
have to touch the radiator.

I used the tool. Maybe my bigger engine guard was my down fall. I fought with it and gave up and pulled down the radiator to get to the last one.

Don't forget the question of will any premixed work?

Greg Cothern · June 12, 2011, 08:06:52 PM

Should be silicate and phosphate free.

Magnum Magna · June 14, 2011, 01:21:35 PM

Thanks!

Been riding Brenda's bike for three days and ready for the Magna again.

Justin · June 16, 2011, 09:42:17 PM

My 94 magna had the same issue start happening about a week ago, pulled apart the auto-petcock and the vacuum diaphragm had a small tear it.

Wonder what the odds are of two bikes having the same issue at the same time almost.

Magnum Magna · June 16, 2011, 11:53:09 PM

Quote from: Justin on June 16, 2011, 09:42:17 PM
My 94 magna had the same issue start happening about a week ago, pulled apart the auto-petcock and the vacuum diaphragm had a small tear it.

Wonder what the odds are of two bikes having the same issue at the same time almost.

Was not the petock on my bike. Vacuum line is next thing I have changed.

Justin · June 17, 2011, 11:22:54 AM

Does anyone know the specific purpose of the auto-petcock?

Is it just to prevent the carb float bowels from overflowing when the bike is off?

And is there any adverse affect to simply bypassing it and sending the gravity feed from the tank straight into the carbs?

cheers,

Justin

LIMagna · June 17, 2011, 12:17:34 PM

The vacuum petcock purpose is pretty much what you describe. You can certainly bypass it if you like but it would be a good idea to turn off the manual petcock when you shut the bike down. I do this anyway, even with the safety provided by the vacuum shutoff because you never know how something may fail. The rebuild kit for the vacuum petcock isn't very expensive (~$35) so you can take your choice.

Justin · June 17, 2011, 04:21:59 PM

I usually turn off the manual petcock myself as well, which is why I was thinking of bypassing it. Also I might upgrade the petcock to a Pingel "Pro-Flow" just debating over the pros and cons of bypassing the auto petcock, mainly I'm just cheap and the postal service is on strike currently in Canada with no clear end in site, so ordering parts my take quite awhile to arrive. I don't remember all the shipping options for Ron Ayers but i believe it is USPS which gets transferred to Canada post.

swamprat5605 · August 09, 2011, 05:57:30 PM

I was having the same problem as you for about a year on my 3rd gen magna and it turned out that I too had a tear in the fuel vaccum rubber diaphram. I used part #http://www.magnaownersoftexas.com/forums/index.php?topic=4202.0