[Usagi on the Moon]

Mad has a red tank with no rust for 300, which is not an "insane" amount of money, but certainly sizable. POR15 has a "fuel tank repair kit" of which the metal prep portion supposedly gets rid of rust, kits about 100. I think my next day off I'll take a look at my fuel and evaluate if there's rust in the tank, then it's just a matter of 100 and time vs 300 and none.
Even if I get that issue solved I'll still have to clean the carbs, again. despair.

 

[Geo Smith]

Keep at it bud. You'll solve your issues.

 

[Usagi on the Moon]

Over last weekend I took out and cleaned the carbs, fuel pump, gas tank as well as replacing the fuel sensor as my old one was only half functional and rusted out. Today it seems it still isn't firing from both cylinders. Do you guys have any suggestions?

 

[Troy Jollimore]

The only thing you can really do is set up an independent fuel feed. Gravity should do fine. If both cylinders run, you know where to look for the problem, if they don’t, you can only directly put fuel down the throat of the ‘not firing’ carburetor and see if it fires. If it does, then you know where to look for the problem.

Otherwise, you’ll be taking that cylinder’s head off and checking/reassembling to factory spec as per the manual.

 

[Geo Smith]

replacing the fuel sensor as my old one was only half functional and rusted out

That was how my fuel sensor was. Had to replace it. Be sure to keep the old one. You can use it to plug the hole in the tank if you decide to line it with POR15. It will plug the hole and protect the threads.

 

[Usagi on the Moon]

So general update,
last time I had issues after my attempts to clean the tank I took a step back and re-evaluated some things.
I got new plugs and gapped them, it was a cheap potential solution and I wanted to start from the top.
I took Geo's advice and drained some gas into a mason jar, now that I had cleaned the tank I wanted to see if there was any particulates where there shouldn't be.
Results? bad. The same black heavy particulates as before and a small "cloud" of something other than gas.
I had resisted pulling the trigger on the por15 in part on funds but also fear of being the 1% who's por-15 "slopped" after treatment. At this stage, I'm going to get the 3 step system and follow it to the letter and then some. Should post after the holidays if that worked or not. Cheers and happy holidays guys!
E: Forgot to mention, both cylinders are definitely firing, so that's why I've come back to the fuel tank.

 

[Geo Smith]

Good luck bud. It's not hard, just time-consuming. Let it dry, let it dry, let it dry. Merry Christmas.

 

[Usagi on the Moon]

Update:
Holidays and the start of new year were a perfect opportunity to treat my gas tank.
POR-15 3 stage kit, followed the directions exactly, applied the sealant, let it sit....for probably a week? Definitely went well above the recommendation!
Now that I've had free-time I started riding the bike again to test it. Long story short it's the same as it was, at first I got a bit excited because my lower gears felt better but, maybe that was placebo.
I made the mistake of taking it on the freeway to see if the higher speeds and rpms would be any better, when hitting 60+ the "chugging" and "lurching" came back.
This time with an oil indicator light, never seen it before! I tried to get home immediately and ended up stalling out on the freeway, when I checked my coolant I was either extremely low or bone dry. The bike struggled to start but after adding coolant and trying a few more times I was able to ride it home. Since I had concerns about the coolant system now, I've added UV dye, (not that the original stuff was hard to see).
I've ridden it two brief times the last two days, both times with the exact same issues, chugging any-time I try to pull faster than 60. Sometimes I can rev past 5-6k rpm, other times I can't. I thought maybe when I was able to redline briefly in first the day after the tank treatment was done it was a sign but, guess not. I took the pen light to my bike after tonights ride, no sploches, no leaks to be found. I took the pen light to the oil window and saw some sliiight reactance, but not enough for me to say there's a blown gasket, after all I don't see smoke, white or otherwise and there's no bubbles in my reservoir when idling.
Frankly I'm confounded.
I know this bike was able to run right, I felt it, I just don't know what exactly the issue is.

 

[Geo Smith]

Sorry to hear about the ongoing issue Usagi. Glad you properly lined the tank. But unless you cleaned the carbs after you addressed the tank rust, your carbs are still contaminated with rust from your unlined tank. Recall, when I was chasing my issues, I was sure to clean the carbs (for the third time) after I lined the tank.

And I wholeheartedly suggest you clean the carbs yourself. It's not hard if you follow the instructions on SVR. But you have to be meticulous. Clean the passages, then clean and blow thrice more. But, now that your tank is good to go, thats should be the last step. It's a good education and you'll save a lot of money.

As for the oil light, that's another issue entirely. And there are a lot smarter members here that I on SVR who can provide some input. Good luck.

 

[Usagi on the Moon]

I suppose I could clean the carbs again. I didn’t hate doing it too much last time and it’s only a few hour project. I do hate overdoing it as I worry about stripping the screws, even with JIS that metal is not great. I assume I should ALSO clean the fuel pump since it’s down the line?

 

[Geo Smith]

Unfortunately yep. The fuel pump and the petcock probably have particles in them. And this stuff works great on the crappy soft screws.

I can't stress enough, make sure you have a strong stream of carb cleaner blowing out of each little passage, then blow out with compressed air. If it is not done thoroughly, you'll have to do it again.

Ziptech did a comprehensive writeup about a decade ago that I followed to the letter.
Dangers of a Low-Carb Diet

 

[RichDesmond]

Good idea to replace the JIS-head screws with Allen-head bolts. A good hardware store should have the right sizes, but you can also order them if you can't find them locally.

And +1000 on Geo's "do it thoroughly" advice. As I've said before, there are carbs that have been cleaned, and then there are clean carbs. Not necessarily the same thing,

 

[Straticus]

Make sure the vents under the fuel filler cap are not blocked. Use the forum search for blocked fuel cap/filler. If blocked they can cause a partial vacuum and restrict power.

Also set the Carb float heights using this information,

1st Gen resurrection

I have a spare set, but you'd have to rip it from my dead arms to get it.This is how I am with my Honda V4 carbs Sent from my SM-N950U using Tapatalk

www.svrider.com

1st Gen resurrection

So I am measuring from the flat bottom of the float and not the corner like Suzukis picture shows Sent from my SM-N950U using Tapatalk The manual is misleading. With the Carb orientated as per my picture you measure from the top of the back of the Float furthest from the FNV to the carb...

www.svrider.com

 

[Troy Jollimore]

As for the oil light, that's another issue entirely. And there are a lot smarter members here that I on SVR who can provide some input. Good luck.

I’m more thinking the oil light came on only because the engine had cut out momentarily, so there was no oil pressure.

 

[Geo Smith]

Good point Troy.

 

[Usagi on the Moon]

I still find it odd that I not only stalled out but that it wouldn’t start up afterwards until I jumped it and had coolant added.

 

[jstehman]

When you say one of the jets hasn't been "drilled out", do you mean the tamper plug on the idle mixture screw?

If those are still on there's your carbs are not clean. No way without removing those screws.

And there is a screen on the backs of the float needle seats.. that will stop fuel from filling the bowls.

The SV carbs are Ridiculously Easy to remove clean and replace. I highly suggest removing them for a proper cleaning, and checking for unrestricted clean fuel flow from the tank through the pump before hooking it back up.

Sent from my SM-N950U using Tapatalk

 

[Usagi on the Moon]

Carbs are pulled off, lines and screws are still marked from previous removal, I’m gonna remove the main ones for the bowl covers and replace them with Allen headed bolts I saw at Ace today. I went ahead and pulled the petcock and fuel pump with them. Nothing of note in either of those, still gave them a good clean, made sure the spring/ball in the pump actuated as I know that can happen, moved fine. I’m gonna study the manual, threads, and what people have posted before I even try to clean these carbs again. I’ve never set a “float height” before and I’ve worked on these twice, so I suppose I need to study. Also I took note of someone’s suggestion about the airboxes boots and sure enough mine had come loose, made sure to give extra to reseating those properly.

 

[jstehman]

Shouldn't have to worry about the float height unless you're changing the float seats and needles or someone set them wrong before. The pictures in my thread show how easy it is to check.

Get yourself some good JIS screwdrivers if you can, and definitely change out the bowl screws for stainless cap screws.



Sent from my SM-N950U using Tapatalk

 

[Straticus]

Shouldn't have to worry about the float height unless you're changing the float seats and needles or someone set them wrong before. The pictures in my thread show how easy it is to check.

Get yourself some good JIS screwdrivers if you can, and definitely change out the bowl screws for stainless cap screws.



Sent from my SM-N950U using Tapatalk

I have to disagree with you on your photos and assumption on the float heights. You are measuring the float heights at the wrong position. You have your measure too close the float axle and there's not enough deflection to set correctly. The floats need to be checked at the furthest point from the Fulcrum. When resting on the Float Needle valve the floats should be parallel with the Carb bodies when held up horizontal to the eye and be 7mm +/- .5mm

Checkout this video. It takes setting them to a super accurate level including angling the carbs and checking that the Spring loaded Float Needle Valve is operating correctly,