Petcock rebuild

[BrettB]

I'm still having fuel problems, so I plan on doing the petcock rebuild.  After looking in shop talk, I am still not certain about the procedure.  When it says to "remove the petcock by loosening the flange nut"  does this mean that I take the entire assembly out of the tank?  If so, after it is rebuilt  is any sealer used or is it more of a pressure fit.

The shop talk article on this is good, but it assumes I know what I am doing..................I don't!

[roboto65]

When you get the tank off look under it where the petcock is and you will see a big nut loosen that and the petcock will pull out be careful as there is a long filter on it and sometimes it does not want to come out and gets twisted when you put it back together just screw it back on..

Cannot remember what seals it oring or washer but most of the time when I pull mine I just screw it back on and it will seal it up

[98valk]

When you get the tank off look under it where the petcock is and you will see a big nut loosen that and the petcock will pull out be careful as there is a long filter on it and sometimes it does not want to come out and gets twisted when you put it back together just screw it back on..

Cannot remember what seals it oring or washer but most of the time when I pull mine I just screw it back on and it will seal it up

O-ring.  suggest installing new filter screen or at least have a spare. mine wasn't dirty but under closer inspection with an eye piece some of the mesh had larger holes than other holes. inconsistant compared to a new one.

[John U.]

An O-ring seals the petcock to the tank. While you have it off you should replace the screen. The tank will sit upright on its nose preventing residual gas from leaking out the opening. It's also a good idea to flush the tank of sediment while you have it disassembled.

[roboto65]

Thanks guys could not remember weather it had the oring or not old age sneaking up LOL

[BrettB]

Thanks for all the info.  I have the petcock kit but have not even looked in it to see if a filter is included in the kit.  What is the best way to flush the tank out once I have it off?

[roboto65]

The filter is Not included and some have mentioned some nuts shaken not stirred but really you just want to get the dirt that the filter kept in there out!!

[BrettB]

OK, I took the tank off and removed the petcock.  The screen did not come out with the petcock so I had to use needle nose to get it out..........it was stuck pretty good but when I got it out it did not look dirty.  I expected to see a bunch of gunk or dirt on it, but I couldn't see anything.  It was obvious though that there had been quite a vacum because the upper portion of the screen (main tank portion)  had been sucked in and would not return to a normal position............I assume that means it sucked shut, causing my motor to stall.  (It did this to me twice, different days with 80 or 90 miles in between).

I then took the petcock apart, expecting to see some kind of damage, wear, or dirt that might cause this.  I did not find anything that looked bad to me.

I put the petcock rebuild kit on and I am now waiting on a new petcock screen/filter, which they did not have in stock (of course).

I am now wondering if I am even fixing the problem.  It seemed to be an intermittent problem (is that common when a petcock goes bad?) 

As I said before, I had just finished installing an in line fuel filter and fuel line quick disconnect.  I know the in line filter is the proper one to deliver enough fuel, and that all the lines were hooked back up properly.

While I am waiting on the petcock screen I will have the tank cleaned.  Does anyone have any ideas what I may have missed.

Will this thing run when I get it back together????

[Daniel Meyer]

Normal for the petcock screen to be distorted.

Check your old diaphram...the bigger one...probably leaking around the "tit" in the middle of it...you can pull on it (stretch) it a bit and see that tit is compromised.

To truly check, you should have pulled a vacuum on the petcock vacuum port before pulling it apart to check it's function.

No gas should flow in any position with no vacuum.

Vacuum should hold indefinately...not bleed down ANY.

When vacuum is applied, LOTS of fuel should flow in "on" or "reserve" and none at all in "off".

Also make sure the vacuum line to the petcock is not split or soft (soft will collapse under heat and vacuum).
Test the new one the same way...

[BrettB]

Thanks Dan.  I'll check what you suggested and probably replace the vacum line just to be sure it is ok and not closing up or leaking.

[BrettB]

I hate to beat a dead horse about my fuel problems, but here is the latest:   I rebuilt the petcock and checked the vacum lines from the tank, cleaned the tank and put everything back together.  I did notice (with a magnifying glass) that the old diaphragm did have wear at the little tit........a little bit of the rubber was worn away showing white material.  I guess that is where it was leaking and since it was so small, it would run for a while then act up.

I put everything back together and added about a gallon of gasoline from a can of fresh fuel.  I was going to fill the rest of the tank at the gas station with a higher octane.  I got it started after some cranking.  It acted cold as I headed out to the end of the drive, where it stalled.  It restarted but was obviously fuel starved.  By now I'm really not dealing with this well.  Every time I do some work, I make the problem worse.  I was about to give up and take it to a Honda shop Monday.  I thought as a last resort I would put more fuel in the tank to see what happened.  I added another gallon (maybe a little more), let it sit a few minutes, and it fired right up. I rode it last night for about 20 miles without a problem.

My wife and I then went on a 120 mile round trip breakfast trip this morning, and not one problem!  It ran great.

Does anyone know what could have caused this?  After having a tank that is bone dry, do you have to add enough fuel to overcome some pressure or gravity to get things started?

My concern now is whether or not it will go into reserve when I get down to a gallon or so.  Guess I had better test this out before long so I don't get surprised.

[John U.]

You didn't say if you had it on reserve when you first started the bike. Fuel should have flowed with the bike running, but with only 1 gallon in the tank it would only flow if on reserve.

[Bone]

If you were on reserve adding more gas makes me think the inline filter or disconnect is restricting fuel flow.

[BrettB]

Yes, I did have it on reserve when I started it. 

I guess the only thing left is what John U. said.  The in line filter and/or fuel line disconnect may be restricting flow.  I'll run it down on reserve and see if she quits again.

Thanks for the input.

[Grandpot]

I had the same thing happen to me after I installed an in-line filter.  As soon as I removed it, the problem went away.

When I removed the filter, I blew into it and could feel some resistance.  Then I blew harder (no jokes please) and it cleared up.  I took the filter apart and it was clean.  I think the viscosity of the gasoline is just enough to stop the flow in a gravity fed system like ours.  This type of filter works on a car because the fuel pump is forcing the gas through at about 5-7 PSI.  The reason the bike started working again when you went to reserve is the additional head pressure caused by the reserve intake being lower than the normal intake.      

[BrettB]

I think I will have to remove the in-line filter.  It just does not feel as responsive to the throttle like it used to.  I would like to keep the quick disconnect, but I don't know if I should keep it on without having a filter down stream from it.  The quick disconnect is nice for trailering and tank removal.

[Black Sled]

Amazingly, I had the same thing happen to me this weekend.  Running out of gas and so hit the reserve - I made it about a mile before it quit.  I came to the same conclusion and pulled the fuel filter out once I managed to get home.  Guess I'll stay close to home next time the odometer approaches 130 miles just in case it wasn't the filter.

[roboto65]

When I first got my bike as in picked it up had a fuel leak turns out the quick connect was leaking like a seive anyhow I took it off when I got home and no more problem but with that big loop in there I could see if gravity could not overcome that loop say like when you get low on fuel where the problem could start.
I think there is a filter in the quick connect too..