Author Topic: Tygon fuel line and clamps (Read 5274 times)

GKreamer · « **on:** April 30, 2018, 06:51:33 pm »

Replaced my original fuel line about 2 years ago and used new stock line clamps. Sometimes I notice some liquid on the left side panel that the pocket in on, but lower near where the carbs are. One day noticed spots on my left jean leg and it is definitely gasoline.

Anyone ever had issues with Tygon line and stock clamps? Was thinking of using a small worm style clamp under the tank, but not on the carb end due to 1. room and 2. I can't recall if that tee is plastic or metal.

Any thoughts? Thanks for reading.

Cal · « **Reply #1 on:** April 30, 2018, 07:42:51 pm »

i think it is more likely it is weeping of fuel from the pet-c***. likely the diaphragm has a pin hole and small amounts of fuel are getting to the vacuum side of the diaphragm and eventually leaking out the small weep hole in the petcock housing.

get a replacement petcock diaphragm kit. I keep one available myself.

Cal

MAN OF BLUES · « **Reply #2 on:** April 30, 2018, 07:54:38 pm »

Quote from: GKreamer on April 30, 2018, 06:51:33 pm

Replaced my original fuel line about 2 years ago and used new stock line clamps. Sometimes I notice some liquid on the left side panel that the pocket in on, but lower near where the carbs are. One day noticed spots on my left jean leg and it is definitely gasoline.

Anyone ever had issues with Tygon line and stock clamps? Was thinking of using a small worm style clamp under the tank, but not on the carb end due to 1. room and 2. I can't recall if that tee is plastic or metal.

Any thoughts? Thanks for reading.

The "T" fitting between carbs is indeed plastic, don't overtighten on it... they become brittle after many years..
As for Tygon fuel line, as nice as it is said to be, it has a few shortcomings.. one of which is the wall thickness, which is significantly thinner than the old rubber ones... this, in turn, makes the outside diameter where the clamp sits, much smaller, and if using with the original ring clamps ( which have taken a "set" on the thicker hose) doesn't make for a robust force to keep them sealed...
If you had NEW spring/rings, and sprung them a bit "tighter" prior to install, you may find much better seal and clamp consistancy.. even if you used the old ones, and sprung them "tighter" prior to install, it amy help, but again, being old, they are softer, and not as springy..and may break.

GKreamer · « **Reply #3 on:** April 30, 2018, 08:38:31 pm »

As a sidenote I also replaced the petcock with a brand new stock one, though I know that can mean nothing as far as this issue is concerned.

I did buy new clamps as well. Just so I understand MOB, you're recommending squeezing (for lack of a more technical term) the new clamps a bit to get a tighter seal? I'll try that and will look at the petcock.

Thank you both for your suggestions.

MAN OF BLUES · « **Reply #4 on:** April 30, 2018, 09:33:16 pm »

Yes, what I'm saying is to grab the ring ends, and pull opposite of each other, making the clamp in its "free state" smaller,
Hope that helps

GKreamer · « **Reply #5 on:** April 30, 2018, 09:55:35 pm »

Ok, thank you again

connie_rider · « **Reply #6 on:** April 30, 2018, 10:10:28 pm »

Was the Tygon hose you installed Metric at SAE?
Reason I ask is; many install 3/8" hose and it's a bit too big. (So the clamp has to compress it more than the stock hose).

Ride safe, Ted

MAN OF BLUES · « **Reply #7 on:** April 30, 2018, 10:43:17 pm »

Quote from: connie_rider on April 30, 2018, 10:10:28 pm

Was the Tygon hose you installed Metric at SAE?
Reason I ask is; many install 3/8" hose and it's a bit too big. (So the clamp has to compress it more than the stock hose).

Ride safe, Ted

That would be a problem, as the line size should be 5/16" or 8mm I.d.

GKreamer · « **Reply #8 on:** April 30, 2018, 11:41:12 pm »

I bought https://www.amazon.com/gp/product/B0022ZWTA0/ref=oh_aui_search_detailpage?ie=UTF8&psc=1, 5/16" I.D. I know some have said Tygon collapses but I've not experienced even in summer heat in VA, 95°+90% humidity in bumper to bumper traffic on I95.

connie_rider · « **Reply #9 on:** May 01, 2018, 02:45:04 pm »

Quote from: MAN OF BLUES on April 30, 2018, 10:43:17 pm

Quote from: connie_rider on April 30, 2018, 10:10:28 pm
Was the Tygon hose you installed Metric at SAE?
Reason I ask is; many install 3/8" hose and it's a bit too big. (So the clamp has to compress it more than the stock hose).

Ride safe, Ted

That would be a problem, as the line size should be 5/16" or 8mm I.d.

I agree. That's why I mentioned it.

Looking at GKreamer's Tygon, it appears that the wall thickness is greater than the stock hose.
I suspect the Tygon is also stiffer.
Both make it more difficult for the original spring type clamp to compress it enough.
Heavier spring type, or screw style clamp's will solve the problem.

Ride safe, Ted

MAN OF BLUES · « **Reply #10 on:** May 01, 2018, 08:21:09 pm »

Quote from: connie_rider on May 01, 2018, 02:45:04 pm

Quote from: MAN OF BLUES on April 30, 2018, 10:43:17 pm
Quote from: connie_rider on April 30, 2018, 10:10:28 pm
Was the Tygon hose you installed Metric at SAE?
Reason I ask is; many install 3/8" hose and it's a bit too big. (So the clamp has to compress it more than the stock hose).

Ride safe, Ted

That would be a problem, as the line size should be 5/16" or 8mm I.d.

I agree. That's why I mentioned it.

Looking at GKreamer's Tygon, it appears that the wall thickness is greater than the stock hose.
I suspect the Tygon is also stiffer.
Both make it more difficult for the original spring type clamp to compress it enough.
Heavier spring type, or screw style clamp's will solve the problem.

Ride safe, Ted

I'm hearing ya bro

If it is a "stretch" fit, its the wrong size...
As for what GK bought, Motion pro is what Murph sells, but the picture shown, may be of a smaller I.d. tube, and may be visually decieving, and as pretty much everywhere I've looked, at "bulk suppliers" for Tygon grade F-4040-A, (the specific fuel resistant grade), all were 1/16" wall for 5/16" barb fitting hose...
I did find some suppliers that offered an .093" wall, but no specific "grade" was in the literature, just Tygon...
Grade E-3603 does come in .093" and .125" wall, but its a lab grade, and 2x the price...

Tygon, by the way, is a tradmarked brand, manufactured by St. Gobain,

I can say that all the TYGON hose should be marked, every foot along its length, with the Tygon mark, the grade, and the I.d., o.d., wall thickness, and pressure and temp rating... its a UL and CSA requirment, so someone that has some of that motion pro hose can report back as what the markings actually are on it..
Grade F-4040-A is also pretty soft, softer than the oem id imagine, which is around 60-65 durometer, tygon notes 55 duro on the grade.

Bud · « **Reply #11 on:** May 01, 2018, 09:52:03 pm »

I had my own tygon fuel line experience recently on my silverwing project. It goes on the fittings lots easier and is more flexible than the fuel line I got at the Suzuki dealer. The problem is the tygon seems stiff enough for a bend...and it is..until it gets hot....and then what was ok when cool kinks when it gets hot. I was out on the test ride and the right cylinder started starving for fuel because of that kinked line. When I slowed down it finally got enough fuel to run properly again. Found the problem once I got home. For anything with a bend, I would stick with the standard stuff made for bikes. HTH

GKreamer · « **Reply #12 on:** May 01, 2018, 10:49:00 pm »

I have the new house and clamps in my Partzilla shopping cart. Going to compare with ordering from a local Kawasaki dealer to see if shipping makes any discernable difference.

GKreamer · « **Reply #13 on:** May 09, 2018, 01:04:37 am »

Did three things:
1.Ordered a stock fuel line and two clamps from a local dealer.
2. Bought a pack of the smallest size hose clamps I could find and installed one.
3. Cleaned the panel of all stains.

When I propped up the tank and barely touched the fuel line at the petcock the line would move and I could see air get in and actually see air bubbles. The fuel line popped right off super easy, scary easy actually. The line looks good and tomorrow I'll see if there are any new stains.

MAN OF BLUES · « **Reply #14 on:** May 09, 2018, 06:30:35 pm »

Quote from: GKreamer on May 09, 2018, 01:04:37 am

Did three things:
1.Ordered a stock fuel line and two clamps from a local dealer.
2. Bought a pack of the smallest size hose clamps I could find and installed one.
3. Cleaned the panel of all stains.

When I propped up the tank and barely touched the fuel line at the petcock the line would move and I could see air get in and actually see air bubbles. The fuel line popped right off super easy, scary easy actually. The line looks good and tomorrow I'll see if there are any new stains.

Cool
Pertaining to my post #10 above, on the Tygon tube you bought, what was the nemenclature marked on the tubing itself, it should be marked.like I mentioned.
Thanks in advance,

GKreamer · « **Reply #15 on:** May 10, 2018, 12:52:14 am »

Tomorrow I'll pull the side panel and look and report back. I saw a few small spots, I'll check the leftmost carb boot tomorrow too.

MAN OF BLUES · « **Reply #16 on:** May 10, 2018, 09:21:00 pm »

So, again, about the Tygon tube.... what is written on it...
And again, thanks in advance,

GKreamer · « **Reply #17 on:** May 11, 2018, 06:01:51 pm »

Only markings are MOTION PRO®. Will post pics I took shortly.

MAN OF BLUES · « **Reply #18 on:** May 11, 2018, 07:10:03 pm »

Quote from: GKreamer on May 11, 2018, 06:01:51 pm

Only markings are MOTION PRO®. Will post pics I took shortly.

On the actual tubing? I'm not talking about the package, the tubing itself should have markings on it...

If you zoom in on the roll of tubing in this ad, you can somewhat see the markings on the hose itself...
https://www.amazon.com/gp/product/B0022ZWTA0/ref=oh_aui_search_detailpage?ie=UTF8&p&sc=1

I'm trying to find the grade, and size, and that should be marked on the tube, its industry standard, and Motion Pro doesn't manufacture it, they buy bulk, and cut it and repackage it for sale.

m in sc · « **Reply #19 on:** May 11, 2018, 07:19:47 pm »

ive had good luck using small wire/zip ties on peoples bikes running tygon vs clamps. personally i dont liek it, as said, kinks easy. i use the blue urethane stuff from parts unlimited or oem stuff where i can.

GKreamer · « **Reply #20 on:** May 11, 2018, 07:54:35 pm »

Here's what's on the tubing:

GKreamer · « **Reply #21 on:** May 11, 2018, 08:00:36 pm »

Pulled the belly pan and both side panels and checked all carb boot clamps. The leftmost carb was loose so I tightened it and snugged the rest, both carb side and cylinder side. Next run we'll see if it is resolved. Here's what I did on the petcock:

GKreamer · « **Reply #22 on:** May 12, 2018, 09:09:48 pm »

The tightening of the leftmost carb boot did the trick. Took a 40 mile test ride and no new leaks.