Motorcycle not running properly

[Guest]

I just bought a 79 suzuki gs550 (it is an E model but it was one of the first 111 made in January of 79 and they factory built it to look like an L model so I'm not sure which parts are of the E model and which are of the L model). The bike starts and runs, but it has hardly any power (bike stuttered and hesitated through acceleration and had no zip). Cylinder 3 exhaust remained cold after riding. Spark plugs were BLACK.

We thought maybe the carbs were dirty so we pulled them apart and cleaned them and they were quite clean. I've been running seafoam through the bike. Took out all jets/needle valves and blew out with compressed air and cleaned with small copper wire. Put back together and bike ran the same.

Fuel tends to puke out of the overflow tubes when the bike is sitting not running (may be leaking while driving but cannot tell). Bike always smells like gas.

We checked compression and spark and had both although we thought the spark looked a little weak so we replaced the coil. The bike seemed to run WAY better - no stuttering/hesitation through acceleration but new it could still run better.

Started the bike up again today and it was back to stuttering/hesitating. Cylinder 2 actually cut out now along with cylinder 3 and the power dropped drastically more - bike didn't really stutter just had no power.

I'm assuming something must be going on with my fuel level in the bowls? - as shown by fuel puking out of the overflow tubes? Either the floats are set at the wrong height, the needle valve isn't seating, or fuel is somehow leaking into the carbs? If too much fuel is in the bowl could it cause the bike to run rich and actually cause the fuel to not ignite in the cylinder?

I'm a newbie trying to learn. I currently have the carbs out of the bike - the O-rings are shot and the gaskets look like they could be replaced. Could you recommend a place to buy a carb rebuild kit and also recommended fixings to the issues?

[fastbysuzuki]

Firstly you should follow the carb rebuild tutorial here there is lots of information including manuals here
as for the overflowing problem it looks like your petlock (fuel tap) is not working and letting fuel flood the carbs you need to check your oil level as the fuel will get into your crankcase and you do not want that at all, if your oil level has risen you need to drain the oil and renew it but before that you need a new petlock or the same will happen again.
you can get a full set of carb orings from Robert Barr a member here.
there are tutorials on coil testing on bikeciffs site.

[cowboyup3371]

Don't buy a carb rebuild kit - just get the orings from Robert Barr, www.cycleorings.com, and reuse what you have. Being you are from Canada, I don't know if you can get ahold of the Berryman's dip but there should be something just as useful there. As FastbySuzuki said, there is a great cleaning tutorial for the VM carbs on Basscliff's site, http://members.dslextreme.com/users/bikecliff. Pick up new bowl gaskets from your favorite Suzuki dealer or I just noticed Parts N More has them for $5 each and they are on your side of the border.

[Steve]

We thought maybe the carbs were dirty so we pulled them apart and cleaned them and they were quite clean. I've been running seafoam through the bike. Took out all jets/needle valves and blew out with compressed air and cleaned with small copper wire. Put back together and bike ran the same.

Please add more detail about how you "cleaned the carbs".

If your cleaning process was exactly as described and you only pulled the jets to clean them, you are about 30% done. Yes, the jets do get dirty and clogged, but so do the passages inside the carbs. The carbs need to be soaked in carb cleaner dip overnight or cleaned in an ultrasonic cleaner to remove all the crusty crud INSIDE.

.

[danbobberino]

Thats perfect. I'm just reading through the carb rebuild tutorial. That's what I was looking for.

The guy who had the bike had it sitting for 10 years and took the carbs apart and cleaned them except I don't believe he put the parts for each carb back in the original carb it came out of. That makes me think I need to replace the float needle valves and seat?

I'll order the o rings from Robert Barr and find some new gaskets.

I've got some reading to do.

Thanks

[ukjules]

What about tuning ?
I assume you have it all spot on ? Valve clearances ,
Timing , plug gap , coils + ht leads + plugs good.
Air screw set standard to start by colour / state of plugs ?

Also have you standard exhaust ? And thus
standard jets ?

Re carbs:
On all my bikes I took a risk that later I found was no
risk. I simmered my carbs in a solution of
Lemon juice and water for 30mins.
This on my gsx, 750r1 and gs550.

The result for me has always been along
with tuning a perfectly working tunes bike.
I did it as I wanted the bike working the same day
I started on a no start issue.

[danbobberino]

Don't buy a carb rebuild kit - just get the orings from Robert Barr, www.cycleorings.com, and reuse what you have. Being you are from Canada, I don't know if you can get ahold of the Berryman's dip but there should be something just as useful there. As FastbySuzuki said, there is a great cleaning tutorial for the VM carbs on Basscliff's site, http://members.dslextreme.com/users/bikecliff. Pick up new bowl gaskets from your favorite Suzuki dealer or I just noticed Parts N More has them for $5 each and they are on your side of the border.

Do I need to purchase one kit for $18.85 US or do I need to purchase 4 kits? (1 for each carb?)

[sam000lee]

Just one kit for four carbs - Get the "Viton intake O ring kit", also, for ~$4. It's well worth it to also get the stainless allen screws (also cheap ~$4) so you don't have to worry about stripping the original screws if you reuse them.

[danbobberino]

Just one kit for four carbs - Get the "Viton intake O ring kit", also, for ~$4. It's well worth it to also get the stainless allen screws (also cheap ~$4) so you don't have to worry about stripping the original screws if you reuse them.

I ordered the factory intake O ring directly from Suzuki so I'll have those new. I'm from Canada and he says that he doesn't ship fasteners to Canada so I'll have to check that out....

[Big T]

The fact that 2-3 are misfiring points to ignition. Does the bike have points?

[danbobberino]

It does and we set them just set them. Set them to .012 and set it so they open on the proper "F" make.

The petcock is leaking fuel down the vacuum hose into carb 3 which is the cylinder I'm having the most problems with. I am frantically trying to find a petcock but partzilla says it is a 44300-45270 but I can't seem to find any? Any idea if another one would work?

[Big T]

For now, just put a cap on the vacuum port on #3 carb and use the Prime position as ON

Check the points and see is they spark when the bike is running.They shouldn't do that

Also, check the Top 10 Newbie Mistakes thread

[fastbysuzuki]

Plugging the vac line and using prime is ok providing your needle valves will hold against weight of the fuel in tank if not your oil will be contaminated with petrol I suspect it already is as you have had petrol down the vac line.

[danbobberino]

For now, just put a cap on the vacuum port on #3 carb and use the Prime position as ON

Check the points and see is they spark when the bike is running.They shouldn't do that

Also, check the Top 10 Newbie Mistakes thread

I took the stator out of the bike and had to drain the oil. I am not sure how to tell is there is gas in the oil but I'm suspecting there was? Also, my petcock doesn't have a prime position, only Reserve and ON.

We set the points as I mentioned but they were sparking! Does that mean I need to increase the gap size? Or are the condensers bad?

[hillsy]

Smell the oil - if it smells like gas, there's gas in it.