Reviving an Old Bike, Please Help.

[Jebus23]

I am new to these forums however, I am not new to the power of online technical forums! (I'm pretty obsessed with the forums for my VW). I do apologize since I realize how annoying these repetitive forums can be. I did search and thought this bike had its own unique problems to deal with. Anyways on with the post. I'm trying to get this bike running for a friend. It is a 1980 Suzuki 550 with about 25k on it. It has been sitting for about 3-4 years.

Gas is new as of last summer, plugs seem fine, air filter is shot, battery is charged, and the carbs needed a cleaning. I took the carbs (CV) off (pain in the arse) and cleaned and adjusted them. I did not however let them soak, just gave them a really thorough cleaning with carb cleaner and and air compressor. I noticed on two of the carbs there was a spring missing on the "valve with miniature filter under the float that is attached with 1 screw" but I didn't know if that was a big deal since I figured the pin would still depress once the float was filled. Other than that the air screw was only 1 turn out on all of them so I corrected that to 3 1/2 turns out. I put the carbs back in, sealed everything up and gave her a try. Nothing. I pulled 1 plug to see if it was sparking, and it was so I knew it wasn't getting gas. I also pulled a drain plug on the float bowl after cranking and it was dry. NO GAS! So I checked the fuel line. Sure enough it was kinked. I fixed that but while trouble shooting I took off the gas shut off valve (something cock...I always forget the silly word) I separated it and saw the diaphragm had a small break in the seal but figured when I put it back together it would seal it fine. Put everything back together. And nothing. So I sprayed some started fluid in the air box. Started right up. Died Sprayed again. Started right up and I sprayed short bursts to keep it alive until it could on its own. After a few "keep alive" squirts, I would stay running. It was on full choke of course. I let it run a few minutes. The idle was kind of high at about 2000. As soon as I let the choke off it would die and as soon as I gave it throttle to try and keep the rpms up it would bog and die. It also seemed like not all of the cylinders running. The carb leaked a bit (1 mystery leak that looked like it was coming from a bad gasket and one from a lack of a gasket on a drain bolt) It didn't seem like enough gas to make the bike not run correctly though. These symptoms lead me to believe it still isn't getting enough gas. Should I replace that whatchamacallit cock gas shut off thing? Re clean the carbs and let them soak? Do I have an electrical problem? Please help!

 

[dwfranke1]

wow what a post
replace the PETCOCK, or at least put it on prime to see if your getting gas out of it, the carbs are a whole different story, take them apart and soak each part, the jets are super small and the pilot jet is even smaller, those can clog shut quickly, look thru the jets when you get them out, there should be light shinning thru them if only a pin hole size. it sounds like you are getting some spark if it runs on starting fluid
good luck

 

[Jebus23]

When I took apart the carbs. I literally took apart every piece and screw and everything and cleaned them. All of the jets were clear.

 

[Larry D]

Are the carbs still apart ? Have you been to bikecliffs site and checked out the tutorials ?
http://members.dslextreme.com/users/bikecliff/

You should replace all the o-rings in the carbs, get them from here.
http://www.cycleorings.com/

While the carbs are apart set the float heights.
These bikes require the valves be adjusted every 4-6 thousand miles. Do you know if they've ever been done ? If not, do it.

I noticed on two of the carbs there was a spring missing on the "valve with miniature filter under the float that is attached with 1 screw"

Not sure what you mean by this.....I think you mean the needle valve and it's seat. It's not a minature filter.....Regardless, get these fixed. Here's the carb cleaning series from the homepage of this site.
http://www.thegsresources.com/gs_carbrebuild.htm

A new petcock sounds like it's needed too.

Good Luck and enjoy

 

[LarryA_Texas]

When I took apart the carbs. I literally took apart every piece and screw and everything and cleaned them. All of the jets were clear.

OK...first, gas that was new last summer isn't new anymore. Replace that. Second...if the bowl is dry you have to correct that before you do anything else. The petcock diaphragm shouldn't have any tears in it...replacements are available in the form of a rebuild kit. $10.

Cleaning carbs is sometimes hit or miss. Sometimes you think you have them completely apart and have missed something. Some very experienced people here will tell you they have to be dipped and that's true. But I've done OK on CVs that were not in bad shape with spray. Make sure you get the needle jet out...it's an emulsion tube and there is a gap behind it that you can't get to by any means if you don't remove them. Same with the pilot jets.

Now make sure there's nothing in the tank that is gumming up your freshly cleaned carbs...it's hard to believe that a bike sitting for 3 or 4 years didn't have some sediment in the tank. Pour that old gas into a clean container and look at it carefully for rust, etc. Then put on a good in-line filter (a big one for motorcycles, not a car filter made to use with a fuel pump.)

I'm not sure what spring you are talking about. There is a float...that just hangs down. It presses against a needle valve. The needle valves sit up in a seat held in by one screw. Take that screw out, remove the seat and on top of it is a filter screen. The needle itself has a small pin on the bottom that should spring in, but the spring isn't removable. If you have a problem with those you can replace them for about $10 each. A 'carb kit' is usually a waste of money unless you know you need all the parts in the kit. Most of what they put in the kit is stuff that you won't need to replace.

Since you know you have spark, you can make it run...just give it something to burn. These are tough old machines; you'll pull you hair out until that 'ah-ha' moment when everything comes together it it runs like a scalded cat.

 

[highmileage]

Did you remove and thoroughly clean the pilot jets?

Under the rubber plugs, they unscrew and come out. Don't be surprised if the rubber plugs turn to mush, they're about $2.75 ea at your local dealer. Bet you missed 'em...

A great idea is to use fishing line to clean the little holes in the sides - doesn't gar them up.

 

[Larry D]

Where are you on this big blue planet ?

 

[Jebus23]

I'm in Carmel, Ny. First off, thank you for all the replies. I have a filter on the fuel line going to the carbs. I did remove the screw under the rubber seal in the carb. I cleaned ALL of the jets and I could see through them. I'm going to try a rebuild kit for the petcock. As for the needle valve, it is missing the retaining spring to keep the needle in the housing when the float is not putting pressure on it. It is missing the spring on 2 of the crabs. I don't really see how that would be an issue for "not getting enough gas" though seeing how the only symptom of that would be getting TOO much gas correct? (opening the valve more than usually since the valve falls further out due to gravity) Any other suggestions? This is frustrating as hell.

 

[Larry D]

Take the inline fuel filter off. It may be clogged not letting the gas pass through. The petcock has a filter on it, an inline filter should not be needed. Some folks like 'em, some don't. It may also be the the wrong filter type. If you have one, it should be a gravity type, like what is found on lawnmowers, not one the requires a fuel pump.
Have you taken a good look inside the tank ? Is it nasty/rusty in there? What did the petcock look like ? Was the filter crudded up ?

 

[Jebus23]

The petcock had some sediment on the bottom of the "stick filter" but it didnt look like anything major. The filter on the line looks much like this http://www.scootusa.com/gas_line/filter_big-new.jpg .... I will take it off. Apparently it was put on by the dealer but I questioned why it was on there too.

 

[waterman]

Jebus, welcome to GSR. Have to agree with others, sounds like petcock needs some attention, carbs could be gone over again, yes I know getting them in and out is a royal PITA.

My question is have you been trying to start without an air filter in place? These bikes are real sensitive to air flow management. They may start and idle but not rev without some sort of filter in place.

 

[Larry D]

Sounds like the carbs are back on the bike.......
If not, fix, fix, fix whatever may be wrong with them while they're out. Needle valves, float heights, etc. Taking those carbs on and off over and over is truely a pain !!! And the bike will never run right with missing parts and pieces in the carbs.
Two of the most important things to do when bringing a bike back to life is.
1) Get the carbs cleaner than clean with proper float heights and all the parts.
2) Adjust the valves.
Okay and one more thing. 3) Ensure the airflow to the engine is correct with no leaks. Whether it's a stock airbox and filter or pods with the carbs rejetted.

 

[Jebus23]

Thank you for all your replies. Yes the air filter is in place. Im going to repair the petcock, fuel line, needle valves, and adjust the valves. I will keep you posted. As for all of the cylinders not firing, should I look into possible electrical problems? Im praying this works.ray:

 

[Nessism]

Sounds like a petcock and carb problem.

Most newbies try to spray out the carbs only to have to tear into them a second, or third time before they are properly clean. Also, the O-rings get old and hard and the only way to get everything to seal properly is to replace them - including the large O-rings on the rubber carb boot flanges. I'll bet you $1 that if you were to ungang the carbs and remove the fuel tubes, the O-rings will crumble and break apart when you try to remove them.

 

[MelodicMetalGod]

Jebus23,

Welcome!

As Nessism mentioned, O-rings s/b considered. The symptoms you've mentioned - hard starting, high idle, throttle causes bogging/dying - were all present in my bike when I rec'd it out of storage. While fuel starvation could certainly be part of the issue, that issue could also be complicated by too much air in mix via leaks.

To get my bike up and running was as simple as 1) throughly clean the carbs, 2) replace the O-rings between the intake boots and the engine. I doubted the need to replace the O-rings...until I did it.

Other things that I would recommend based on your posts:

1) Get new plugs - might as well.
2) Definitely get a proper air filter in place - air is important and you don't want too much (no filter) or too little (dirty filter).

Obviously, you need to get those needle valves addressed and, as everyone will tell you, a valve adjustment will ensure that the valves aren't contributing to your troubles.

Best of luck!

 

[LarryA_Texas]

I noticed on two of the carbs there was a spring missing on the "valve with miniature filter under the float that is attached with 1 screw" but I didn't know if that was a big deal since I figured the pin would still depress once the float was filled. Please help!

I'm still scratching my head on this one. Aren't we talking about CV carbs? Maybe someone here can explain it to me, but I've never seen a float needle with a spring on it. If you turn the carb upside down you have the float...pull the pin that holds it in and remove it. Now the needle valve should just slip out. No spring there at all, unless you count the tiny spring inside the needle itself. But I didn't think those could be removed, so all you see is the needle valve with a pointy tip and a little springy post on the other end. No spring to remove.

Once you pull that out and remove the screw the retainer for the needle valve seat can be removed and you can pull that seat out. It has the filter screen on the top of it.

I still don't see what spring you're talking about, and I'm thinking that someone tried to stop a fuel leak by adding springs that should not have been there. Either they had a bad needle valve, a bad seat, or the float height wasn't set properly. Either way, I don't see why springs would be there, unless your CV carbs are different from every other CV I"ve been inside. Those springs could be the reason your carbs are not moving fuel to the engine. You're looking to replace missing springs, and I'm thinking you should be removing extra ones. Read over the carb cleanup series very carefully and review all those steps with your carbs.

 

[BassCliff]

Greetings and Salutations!

Greetings and Salutations!

Hi Mr. Jebus23,

Yes, there is definitely a laundry list of tasks to revive these old classics. All (well, most) will be revealed below. Just call me the "mega-welcome wagon".

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thank for joining us. Keep us informed.


Thank you for your indulgence,

BassCliff

 

[Jebus23]

Ok so updating this since I still need some much appreciated help. As of now its no longer my friend's bike....It's mine....I bought it! Ok so on with the updates:

I have decided to go with the pod filter route since it is so much easier to access everything. I installed the cleaned carbs, rebuilt and cleaned the petcock, replaced the fuel line, and gave her a try. She starts up (at first needed some help with starter fluid) but only on full choke. As soon as I take it off it dies. Also, when I give it throttle the sliding valve that is part of the Cv boot shutters. This makes me think I have a vacuum leak somewhere. I ordered the O-rings for the intake manifold and I'm praying this will solve my problem. What I do know now from replacing the parts listed above is that I'm getting sufficient gas to the float bowl. I did not soak the carbs or pull them apart but I gave them a damn thorough cleaning with the spray and air compressor. I removed all the jets and screws and they were all cleaned well. So vacuum leak? Ideas?

 

[BassCliff]

Hi,

The Carb Rebuild Series.

You'll be glad you did.

Thank you for your indulgence,

BassCliff

 

[LarryA_Texas]

Ok so updating this since I still need some much appreciated help. As of now its no longer my friend's bike....It's mine....I bought it! Ok so on with the updates:

As soon as I take it off it dies. Also, when I give it throttle the sliding valve that is part of the Cv boot shutters. This makes me think I have a vacuum leak somewhere. ...I removed all the jets and screws and they were all cleaned well. So vacuum leak? Ideas?

Are you trying to run the engine while watching the slides move? That can only mean one thing: you didn't have the air filters in place.

These bikes are very sensitive to air flow. The filter makes a huge difference. With it removed you will never have the proper air mixture and it just won't run right, if at all. If you do go from stock to pods you will HAVE to rejet the carbs. There's no way it will run right until you do. Extra air flow from the the pods require more fuel in the way of larger main jets.

Here's an example from a GS850 I was working on. I had it perfect, running like a champ. Rejetted the carbs and everything was great. Then I noticed the exhaust crossover wasn't connected on one side. I fixed that and it suddenly wouldn't go above 4500 RPM. That slight exhaust leak was enough to screw it up, and I had to rejet the carbs again.

The point: if you go from stock air filter to pods you are going to have to make changes in the carbs. If you're trying to learn anything about how it runs by running it wth the filters off, you're wasting your time. Want proof...lay a piece of cardboard across the back of the carbs so that it covers 1/2 of each opening. Run it like that...you'll be amazed.