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Fuel hose, petcock and inline fuel filter

D

DSAC10

Training Wheels
Hi,

When removing my tank today, I noticed that there was a small rip in one of the fuel lines. This is the very short hose that runs from the petcock to the inline fuel filter.

Firstly, is this fuel filter stock? Or did the previous owner throw something aftermarket on here?



Second, I measured this broken hose to be 1/4" ID, 1/2" OD, though it's hard to be sure with flexible tubing. The question is, can I just go buy any generic tubing with these dimensions from a hardware store to replace it? It is a very small length, maybe 5 inches. Or is there some special type I need?

And finally: is there an easy/good way to remove these darn hose clamps? I think my attempt at removing it may have caused the tear in the first place.




Thanks in advance!
 
I believe the oem hoses are grey. I would recommend buying oem hoses.

The filter is too small. Replace with napa 3006.
 
I like the Moose Racing hose clamps. It helps to handle them with pliars. https://www.bikebandit.com/aftermarket-parts/motorcycle-fuel-and-air/hoses-clamps/moose-racing-wire-clamps-15-piece-assortment-pack/p/36991

For fuel lines you can get OEM and they are taking a long time to ship right now. I decided to get the non-Tygon (not vinyl) Motion Pro hoses here: https://www.walmart.com/ip/Motion-Pro-Premium-Fuel-Line-5-16-ID-x-3-Clear-12-0057/536605450

I heard the OEM hose is technically 8mm but for practical purchasing 5/16 is close enough.
 
Thanks for the responses. Are you sure it is 5/16"? It measures nearly exactly 1/4" on my calipers.

 
The answer to one of your questions is NO the filter is not stock. I suspect that the op put in that small filter and replaced the 8mm fuel line with 1/4" to fit the filter. That is why it split. Inline fuel filters some swear by them some swear at them.
 
JPD said:
The answer to one of your questions is NO the filter is not stock. I suspect that the op put in that small filter and replaced the 8mm fuel line with 1/4" to fit the filter. That is why it split. Inline fuel filters some swear by them some swear at them.
Click to expand...

I'm fairly confident that the hose is 5/16". Others can chime in, but there are lots of other threads that reference this size. Also, that filter you have on there is the K&N inline filter. Definitely use that Napa 3006 that DC Concours suggested.

I believe this is the OEM fuel line part. I ordered it but have not yet used it since I got the motion pro.

Part - 92190-1063 - TUBE,FUEL,7.3X12.5X220
 
those filters are super restrictive (as shown). ive starved a single cyl on a 350 with one of them. take off, throw in trash, or use on a lawnmower.

.02
 
Got it - if ColoradoMike is correct, then 7.3 mm = 0.287 mm, which is somewhere between 1/4 and 5/16". 5/16 plus a clamp is probably a better idea, if I decide not to go OEM.
As for the fuel filter, I have the option of kicking this one out and replacing it with the 3006, or putting in a coupler and running with no inline filter. I'm inclined to go with the 3006 - I know these bikes have a fuel filter in the tank/petcock, but if it fails for whatever reason, then I risk clogging carbs. Which is bad in its own right, but also puts me one step closer to hydrolock.
I've done some reading, and there are suggestions on where exactly to install the 3006. Haven't seen a good picture though - would anyone mind sending me a pic of their setup?

Thanks again guys, I learn something everytime I am on here.
 
I don't have a pic but it is self explanatory. The 90deg elbow goes down into the back of the carbs. You will see when installing.

 
DC Concours said:
You know there is always confusion about fuel lines. I just use OEM but they do cost a whole lot more and as stated, usually backordered.

Does anyone know if the generic 5/16" inner diameter hoses you can buy at local auto stores will work? Like this one:

https://shop.advanceautoparts.com/p/carquest-bulk-hose-tubing-bulk-fuel-line-hose-5-16-i.d.-12-inches-cq24078/5192935-p?product_channel
Click to expand...

I have just heard from SISF to avoid auto fuel lines since parts can break off and cause issues downstream. Cars are more tolerant than bikes.
 
Resurrecting this after a while. Was doing valves, so figured now was a good time to replace that fuel filter. Threw on the Napa 3006 as suggested. However, I did this while I had the valve cover off. Now that it is time to reinstall the valve cover, I find that the new fuel filter (which is much larger than the old one) is blocking the big hose that goes from the cylinder head reed valves to the airbox.

View from the left hand side of the bike:


View from the top/left:


View from the back of the bike:


As you can see, the filter is currently sitting on top of the #2 carb.

One option is to just order block off plates and do away with that hose entirely. Has everyone else done this, or is there just a better way of installing the fuel filter?
 
I ran my filter beside LH carb, visible downwind of fuel tap, and fuel line below carbs.  The black T fitting on carb rack will turn and rotate downward. Allows for no air bubbles in filter. Allows for minimal chance of vapor lock in line or filter. Keeps all in relatively cool areas compared to above carbs. Allows for road side removal and replacement with forceps to pull and replace line from below if such were ever necessary.  All is easy to inspect and get to should need arise. This without any major effort. Hope this helps.
 
Of note, also use same fuel line on gas tank vent running down below bike. In an emergency circumstance road side, would already have a spare fuel line in that.
 
Unfortunately I can't really understand what you mean - probably need a picture!
I seem to have gotten it working by playing with the location of the filter. It still sits on the carbs, but there is now enough clearance for the airbox tube to just about pass over it.
 
Should work fine like that . I got rid of all that stuff on top and plugged the airbox and capped off the tubes on the valve cover . Had it like that for a few years and got the block off plates a couple years ago .
 
It's puzzling. Should work fine. Mine is laid out just like that and with no block off plates. Many people use this setup.
 
The correct hose size is 8mm.
In those countries still using inconsistent measuring standards  :nananana: this equates to 0.31496".
5/16" is 0.3125" so even the 5/16" is a little tighter than 8mm but should work fine.
1/4" is way too tight (0.25") and will split over time if used.

I run without an inline fuel filter as I hate the fact that it takes so long to refill the fuel filter and then the float bowls, that switching to reserve becomes a matter of coasting to the side of the road and then wait 10 secs whilst it all refills.
Without the filter, when the motor first "stumbles", I can flick the petcock to Prime for 10 secs and then back to Reserve and not have to stop.
That said I rarely hit reserve now as I am no longer commuting by bike.
 
JAI, Attached drawing for your review. Better than picture I hope.
 

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Boomer

Of note when running out of fuel and switching to reserve on my C10 I never have trouble. Never pulled over. At first loss of power I switch to reserve and on I go. It is not instant but it is fast. Do watch my rear view though as I turn tap! Have never run out at low speed however. Can not believe my set up and yours could be so different. Curious?

Turning to prime first is a good strategy in case of vacuum tap failure. Thanks for that tip. Will add that to my procedures do believe.

Will add this though on filters, my Virago only likes certain filters. Some I have tried would not flow at all with gravity. Since joining COG I now use a NAPA 3006 on it only too.
 
Jai said:
I seem to have gotten it working by playing with the location of the filter.
Click to expand...

Air in filter can and often does impede fuel flow. Your playing with location displaces air pocket. You might try to position filter so no air is visible. Tapping while tilting it may help. If continuing to run over top of carbs as you are. I would disconnect tap side fuel line at tap and make sure all air escapes filter and line then reconnect. This the difference between what yours is doing and why others have no problem.

Even when running mine below carbs I always remove air from line as above. I have lived in subtropical climate over 50 years. So issues of vapor lock and it's prevention I learned as a teen before fuel injection. Have never had a fuel flow issue with a C10. I never will. This due to preparation as noted. Hope this helps. Good luck!
 
Lee said:
Of note when running out of fuel and switching to reserve on my C10 I never have trouble. Never pulled over. At first loss of power I switch to reserve and on I go. It is not instant but it is fast. Do watch my rear view though as I turn tap! Have never run out at low speed however. Can not believe my set up and yours could be so different. Curious?
Click to expand...
With the fuel filter fitted it always affected me on the motorway at 85mph.
By the time I'd checked around me, and switched it to Prime, it was already dying so I'd have to clutch in and coast to the emergency lane.
Sometimes it would restart before I coasted to a halt, but not often.
Since removing the filter It's not happened to me once.
It could be the specific filter I used that caused it but it was designed for 8mm hose and for motorcycle use.
 
The fuel filter in the tank will  filter the fuel well and the second inline aftermarket filter  cannot filter out anymore than the first one did .... so  can some one tell me ..... what does the  second fuel filter  do besides restricting fuel flow and possibly causing  vapor locks??

 
just adds another point of failure in my opinion.  But then people will wear a belt, and suspenders, to hold their pants up.
:)) :)) :rotflmao: :great:
 
MAN OF BLUES said:
just adds another point of failure in my opinion.  But then people will wear a belt, and suspenders, to hold their pants up.
:)) :)) :rotflmao: :great:
Click to expand...
LOL.. and socks with sandals..
 
Fuel filters don't cause vapor lock, sorry, just doesnt work that way.  Boiling fuel in the bowls can, and does, although i've never seen it on a c10. SOHC CB750, kawasaki H1 and kh400, yes. Rotary valve singles with the carb in the crank case covers, yes. that's an abusive environment for sure, about as bad as it gets. Yet, works. How to overcome real vapor lock? hold throttle wide open, turn motor over, it fires after a few cranks. I've had fuel literally bubbling up the lines on other bikes, and held throttle open, turned it over, and they fire off. as soon as running, they are fine after a few throttle blips. One 71 bonneville in particular comes to mind.

Neither does air in the lines.  Older bikes with multiple single feed lines to each carb off of a 2 or 3 line feed petock get air in them all the time from pulling from one carb or the other and they still flow fine. because, when the needle opens fuel will flow past the air pocket, if there is one.  air does not impede flow unless its pressurised from the other side.  Ive watched this happen more times than i can remember .

I would venture to say that most issues people are seeing and blaming on vapor lock or the like are due to kinked lines or over restrictive filters.  I can see boiling the line if the filter is literally laying on the valve cover, but who would do that?
 
"Vapor lock, an interruption in the flow of a liquid through a fuel line or other pipe as a result of vaporization of the liquid." From Oxford English sourced.

Perhaps I should clarify my statements in this chain of posts. Fuel line routing is a prevention of this possibility above. I would suspect it can take place anywhere in fuel line. Highest part of any loop in line surely. That would be my experience in days gone by anyway.

This air lock without heat factors for lack of better coinage of words I believe is what most C10 owners suffer from. Yes air bubble in fuel line can block or impede fuel flow. I would refer all to one of our members experiments with fuel flow, filters, electric taps, etc. on a C10. Well worth the read.

Yes air is a vapor I know. Also heat introduced into discussion is just another factor that differentiates two possibilities of any lock cause on a C10.

Air in fuel filters can and does facilitate a lock possibility would respectfully submit. A filter is just an expansion of space in the fuel line. Heat of filter by placement in any hot spot or area is just a compounding factor. Especially when filter is placed in a high position of any fuel loop too. Air and vapors collect high. Fuel vapors exist without boiling as well.

So in consideration of above I rout fuel line under carbs so any air in line rises at two points. To the 1) fuel tap and the 2) carb black fuel 'T' between carbs. This so any air in line vents to tank via tap and through carb vents via 'T'. Also it is cooler temps to run all down that way relatively speaking.

Once air vents, fuel flows expeditiously and instantly via capillary action. Air/vapor in lines otherwise is a problem waiting for compounding factors. Capillary action can be impeded by any air lock.

I learned this prevention strategy from experience via early vans with motors between seats. They were very prone to vapor lock from heat. Also my single carb conversion of a Virago was always prone to air lock phenomenon w/o heat as a factor. The filter routing and placement being the critical determination of fuel flow in that configuration.

When I got my C10. I used these experiences to rout lines below after putting carbs to spec. I never have air spaces in lines or 3006 filter. This save for switching to reserve or disconnecting lines for new filter which induces air back in system. Then the routing as discussed quickly vents bubble or bubbles out of line.

Hope these observations help in this discussion. These are respectfully submitted if disagreeing with any poster. Just observations and opinions based on personal experiences. I am a now retired and my expertise was elsewhere. That save the hard knocks in learning as a gear-head since a preteen.

Of note also I now theorize switching to prime before reserve would minimize air induced into fuel line as well save time in the discovery of any failed tap diaphragm. For me this post item in the chain was most helpful in this revelation of a safer procedure. Thanks again. 
 
Yes, youre right. but that flow issue in the line has to be a result of the air in the line being heated and expanding, and that heat source will usually be the carb(hot), or the line on a really hot source, like a valve cover.

an example: My old falcon will do this because of the absolutely dismal design of the inline 6 of that era.  when stopped, the heat from the motor will heat the carburetor up, boil the fuel, and create pressure in the steel line which also transmits the heat in the line and cause the same issues. By holding the throttle wide open, it allows the fuel to be pulled through and pressure to be relieved into the carb bowl  and then allows the fuel to flow thru the line. Ethanol amplifies this effect as well.

this example also works with gravity feed fuel systems. As lee has done, running it down low def helps. I'm not disagreeing to be clear, just clarifying what my experience has been with these issues. But you'd have to try real hard on a C10 to get that fuel that hot in the line, especially with rubber mounted carbs.
 
m in sc said:
Fuel filters don't cause vapor lock, sorry, just doesnt work that way. ................
Click to expand...

Mine vapor locked twice.. both times  my bike had to be flat bedded home and the only times it had ever broke down.. no kinked lines.. no restrictions in the lines. no problems with the lines .. a straight  style inline filter... BUT what I did do was try to find out why and I did... and it was without any doubt..Vapor lock.  So what I did was install clear fuel lines and  I turned the petcock to ON and sat and watched.. with  no engine running..  When the float needles shut off the fuel  flow...air in the form of small bubbles was leaking up past the seats ..  on up the fuel line and into the gas tank..because of the screen filter inside the tank... no issues.. the air just goes into the gas tank....so then I re- installed the inline fuel filter....with the clear fuel lines..... purged all air from the fuel  lines so that I started with  only fuel in the lines.. no air at all...again the air in the carbs would slowly leak past the float seats but this time it collected  and filled the second inline  external fuel  filter with air.. and blocked off the fuel flow.. I could see it as plain as day... vapor lock. the needle seats  leaked air with the engine running and again when  not running  So again I ask.. .. why would anyone want a second filter that cannot filter anymore than the first filter?  What would be the point?  There is no benefit. The second filter has the same filtration level or less than the OEM and will not and cannot  filter out any more than the first filter and you run the risk of introducing other problems..with zero benefit.
 
The only heat related fuel starvation I had was when using the tygon fuel line . That stuff turns to mush and pinches right off when even mildly heated .
 
secondary pleated paper filters are used to catch the smaller particulate that can form in tanks from rust that do slip past stock in-tank filters. thats usually why they are there.

why removing the filter helped would lead me to think it was impeding flow somehow. the OP posted a sintered bronze element filter that was tiny, id def expect that to do what you described, choke the flow.  if removing whatever filter you were using fixed it, that's great.  :great: 
 
Daytona_Mike said:
[So again I ask.. .. why would anyone want a second filter that cannot filter anymore than the first filter?  What would be the point?  There is no benefit.
Click to expand...

True as stated but there is more to it. Easy answers. 1) In my case out of three taps in my stash I had, the original filters were brittle and did not seal at base due to bowing. New one ordered was "whiter" with same bow affliction. 2) The external filter is visible for inspection and easily replaceable without much ado 3) why have two when one external will do. I find great benifit in all that. I like easy maintenance. I like being able to do it at a glance.
 
I've added secondary fuel filters on all the C-10's I've had {4}.
I did it because I feel that they catch smaller particles than the OEM screen in the tank.
I have not had a problem "with the filters".

NOTE:
I "have" had fuel starvation on one occasion.
  When I got home from that ride, I removed the Tygon hose/{threw it as far as I could}/kept the filter/and installed new OEM hose.
        "Solved my problem".

In the 20 years that I've rode Connies, I've seen the fuel starvation discussion "many" times.
So, I have been concerned with it too, and looked for the cause of the problem.

My thought on the occasional fuel starvation is;
In most cases; "The problem is not the filter".
The problem is;
    People add a filter and tighten the bend of the hose by leaving the hose too long.
            When the hose get's hot, it collapses at that bend. {Particularly if you have a Tygon hose}
I solved this by not using Tygon, and shortening the hose enough that the bend is less severe.

Ride safe, Ted
 
I've put in a few shot rides (50 mi ish) with the new filter installed as  above, and everything seems to be fine for now. I needed to add some hose - the Kawi dealership sold me motion pro stuff, which seems to be holding up just fine. I've actually purchased an extra couple of feet so that I can supply fuel to carbs with the tank off the bike, during carb sync.
The bike runs a lot better now, but I also did just do a valve adjust. Let's see how it feels after  carb sync, too.

Thanks for all the good info!
 
Regarding the discussion of fuel lines; I have a large collection and had pulled out and installed what was labeled as ‘Tygon’. I was shocked when it turned rock hard in 3 months. I mentioned that to some coworkers and they advised me that there are several grades of ‘Tygon’ tubing/hose. I followed up with my own research and found that to be fact. So you need to be careful what grade you purchase. I believe the ‘motion pro‘ / ‘OEM’ style is made of ‘buna’ and is the best choice.
 
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boomer said:
The correct hose size is 8mm.
In those countries still using inconsistent measuring standards :nananana: this equates to 0.31496".
5/16" is 0.3125" so even the 5/16" is a little tighter than 8mm but should work fine.
1/4" is way too tight (0.25") and will split over time if used.

I run without an inline fuel filter as I hate the fact that it takes so long to refill the fuel filter and then the float bowls, that switching to reserve becomes a matter of coasting to the side of the road and then wait 10 secs whilst it all refills.
Without the filter, when the motor first "stumbles", I can flick the petcock to Prime for 10 secs and then back to Reserve and not have to stop.
That said I rarely hit reserve now as I am no longer commuting by bike.
Click to expand...
After years of fighting with different line materials, line lengths, and filters, I got around the kinked line problem by not bending it. I got two 90 degree brass 5/16" barbed fittings and put one between the petcock and filter. The other went between the filter and 'down tube' to the fuel rail. Does it add more connections so theoretically more potential problems? Sure. But it fixed a real problem and I've not noticed any flow problems or leaks since. YYMV...
 
Mark, NOTE: I do use a filter on all the C-10's I've had over the years.
Over they years I've heard a lot of stories about the filter etc reducing flow too much
The only time I ever had a problem was when the hose collapsed. {with Tygon Tubing}
In that case, I also installed something to help with that collapsing problem.
On that bike, {Instead of the 90* you used}, I formed some SS Tubing for the bend.
Also {Instead of the 2nd 90*} I use the NAPA 3006 fuel filter as it has a 90* built into it.

Ride safe, Ted
 
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