79 kz650b leaking gas out of carbs 1 and 3??

Limey, don't do that again! You can fix the crack by finding a two part epoxy like JB Weld. Not sure if you can get this stuff in Limey-land but it is very readily available here in the states. It is impervious to gas. You just mix up a bit and smear some along the crack. Once the stuff has set up, you can get a can of spray carb cleaner. Put the straw on the tip of the cleaner nozzle. Put the tip in the hole on the BOTTOM of the bowl and put your finger over the top of the overflow tube and check to see if anything comes out the crack. If you smeared JB Weld on all the crack, nothing will come out. I test ALL bowls with an overflow that come through our shop because nothing is more annoying than finding this problem when setting the fuel level prior to sticking the carbs on a bike for tuning/testing.

wiredgeorge wrote:

Not sure if you can get this stuff in Limey-land but it is very readily available here in the states.

Hmmm.... Last time I looked, Michigan was in the States :dry: (Just kiddin)

I thought about that - and actually tried something similar, but it still blocked the overflow tube - so I gave up!

chopaweeza wrote:

Never and I do mean Never under any circumstance use a product like Seafoam on a bike . It is the quickest way to dislodge crud from your tank and that crud will block every nook & cranny in your carbies. I repaired a CB750 , a Z650B1 and a GSXR750 last year that had used similar products after they bought it off ebay as a "Wonder carb & tank cleaner". The GSXR & CB carbs required a strip down and an ultra sonic cleaning and a complete rebuild using all new parts(at a cost of $650 for the CB750 and over $800 for the GSXR). The Z650 carbs were that blocked that I ended up binning them and buying a replacement set . That stuff is a bikes worst enemy . You think it's going to take the place of a carb rebuild but it makes the situation way more worse.

Sorry Chop...but that's utter nonsense. I have used Seafoam (as directed on the bottle) and have NEVER had any problems due to its' use. This product has saved me hours of carb repair and has kept my system clean and leak-free since I first used it. I use it as directed two or three times in a riding season. I have never had any carb leaks since I started using this product.
Those who have problems with these type of products are likely the ones who think more is better and end up ruining their seals. Use as directed and it will be OK. I speak of the SEAFOAM only. Can't vouch for the other products.
That's my 1%
Peace

SEAFOAM... My take on it. I doubt it will do much good if you put it in the gas tank if your intention is to clean the carbs. It isn't great for removing old gas or aluminum oxide (white powder). It does a fair job but not really great of removing carbon deposits. If you want to clean the carb venturi, buy some SEABREEZE made by the same folks... same stuff in aerosol form. That stuff is better at cleaning carbon in the venturi but more importantly, it cleans combustion chambers pretty nicely.

Seafoam can be used in engine oil or in gas pretty safely I think... I won't argue about using it in a rusty tank as I have never done so and the Brit fella's warning would stop me from trying because if it lifted scale, I wouldn't want to go there... he seems like a fairly knowledgeable fella.

I know a lot about Seafoam use. It is the favorite drink of all Vulcan riders/owners. The Vulcan combustion chamber is SMALLLLLLLLL. The coils on the 1500A model are WEAKKKKKK as it the spark made by the IC Igniter. If you put some Seafoam in the gas of a Vulcan with sooty combustion chambers, the thing will smoke like all get-out for an hour or so... till the chambers get clean. In fact, Kawasaki Tech has told a few Vulcan owners OFF LINE that they HIGHLY RECOMMEND using this stuff on a regular basis. I was one of those folks. An even better tool for cleaning carbon out of combustion chambers is the Yamaha product called Ring-Free. It doesn't do anything for carbs but it cleans carbon nicely. Yet another product is call Techron. I can't recall which gas company puts that stuff in their gas but if you use it straight, it works really well... Problem is, when you get it in gas, it is kind of weak I suspect and unless you use that brand every fill up, there won't be a lot of benefit. If you mainline the stuff in your gas, it cleans combustion chambers nicely.

Anyone ever gone through a cylinder head? The goo that bakes on exhaust valves and coats combustion chambers is carbon and other goo-deposits (tech term I guess). That stuff can eventually keep the valves from sealing. No amount of valve adjustments will give you compression if your cylinder head is packed with carbon and goo... Part of any top end job is to clean this stuff off valve stems and combustion chambers.

Oh yeah, don't get excited about my opinion... only an opinion. The forum is here to throw out opinions.

I have experienced this several times with my 78KZ650B in the past. It usually happens when the bike it placed on the center stand.

I also resolved the problem by tapping the carb with a rubber handle and throwing up onto the c-stand a couple of times.

It might be a good idea to check your plugs and see if they are toast. Seemed to work for me.

I have not had that happen in quite a while and I did not have to rebuild the carbs. After it stopped i took the bike for a nice long run and problem fixed for $10 and 10mins of time.

i figured it out!!!! when i pulled the carbs and looked VERY carefully i noticed the floats were slightly bent on the problem carbs.... the bike runs great. thank you very much for all the help

furby1184 wrote:

i figured it out!!!! when i pulled the carbs and looked VERY carefully i noticed the floats were slightly bent on the problem carbs.... the bike runs great. thank you very much for all the help

Glad to hear you found and fixed the problem. I feel the need to drop my two cents in on the topic of cleaning carbs in response to everyone else who has commented on it.

I used 3/4 of a 12 ounce (340g) spray can of a product called CRC Throttle Body & Air-Intake Cleaner on my pair of carbs from my '82 KZ440. The linkage was gummed up and barely moving and there was very heavy varnish inside the carbs. Two squirts on the linkage and inside each carb and they were moving freely, 3/4 of the can and ALL the visible varnish was gone and the insides of each carb looked new again. I sprayed into the carbs from both sides to cover as close to everything I could. I got this product at Advance Auto Parts (Kragen, Checker, Discount Auto Parts or whatever other names they also go by).

Seafoam...when used as directed is a great product...it can remove particles that could clog things up though...if your parts could have things that could be dislodged then they should be cleaned and flushed while off of the vehicle then you can use the Seafoam when the part is reinstalled. If you have rust in a gas tank then DO NOT use Seafoam until the rust has been cleaned out of the tank...Iron Oxide isn't the best form of fuel. :blink: