advice for obsolete leaking fuel line O ring

[wetwolf]

ok, I'm coming up with a 2-010 from the new measurement in SAE size. you win Chuck! I'll se if I have any hanging around if you dont.

Da oring Wolf

 

[BkerChuck]

Glad this is working out for you Gary! I have a CB400F that I rebuilt the carbs for almost identical to what you're working on. In my case the crossover o-rings were in decent shape and I was able to reuse them. For future reference for everyone there are differences between metric and SAE o-rings but in an awful lot of cases the SAE o-ring will work fine. In a case like this it is a static seal. There is no rotation or sliding back and forth and it's a low pressure situation as well. Any o-ring that will allow a small amount of squeeze to create a seal will work as long as it's close to the correct size. Viton is the optimal choice for temperature and resistance to fuel but I'm not even sure that's what Honda used on these bikes when new.

 

[garyahouse]

Chuck,

Harbor Freight mislabelled their O Ring set. All of the 1.78mm O Rings are undersize. They should measure .070 thick, but they are showing up as .060-.063 depending on the size. They will not work and will have to be returned. They are a dark coffee brown color. Assume that's the normal Viton color, but just won't work.

Please send me about 14 (couple extra just in case) of the size you recommended earlier.

I am so frustrated that this is taking so long. My daughter is chomping at the bit to get back on her Honda... it's been so long since I started this project. Today is her birthday oddly enough. I'd hope to have the bike running today. What a surprise that would have been.

Oh well.

I'll send my address along by PM shortly.

Gary

darksider #44

 

[BkerChuck]

Gary, I'll go pull the o-rings and throw them in an envelope right now. They'll be in the mail tomorrow. PA to FL if they go out tomorrow you should probably see them by Saturday.

 

[garyahouse]

I sent you PM. Assuming these things will fit??? And how much do I owe you?

Gary

 

[BkerChuck]

Gary, PM received and responded to. Tell your daughter Happy Birthday and just call it good forum karma. I left you an explanation in the PM but suffice it to say the cost to me is so minimal it's inconsequential. I've received my share of help from folks on here and try to do what I can to offset what I've been given Wish we'd had the chance to actually meet IRL at EOM last year but alas it wasn't meant to be. Someday when that works out just buy me a beer.

 

[garyahouse]

 

[garyahouse]

Received O things in mail from Biker Chuck. Looks as though they'll fit with about 10% compression within the gap they must seal. Will work on assembling carburetors tomorrow or Monday. Thanks again to all who replied.

Gary

darksider #44

 

[garyahouse]

O Rings installed. No more leaks. Now we're on to figuring out why there's no power to the coils. The saga continues....

Gary

darksider #44

 

[BkerChuck]

On my CB400F I ran into several electrical issues that finally traced back to a defective fuse box. Take the front cover off and the glass fuses looked fine. Unbolted the fuse panel and removed it from bike, took off rear cover and soldered connections were crap. I've been through 3 used fuse panels which all crapped out pretty quickly. There is a guy on one of the SOHC forums making a brand new fun box with blade style fuses that is plug and play. Since I installed it no more problems.

 

[garyahouse]

No power to the coils: forgot to hook up the wire coming from the breaker points to the wiring harness. DUHHH... Bike is running now but need to clean out a nasty gas tank. I should have drained it and brought it in the house. Oh well. Amazing how quickly gas turns to varnish and a tank begins to rust out.

Also dealing with a VERY stiff clutch. This time I took it up to Honda to deal with the clutch. Out of time and daughter OK'd the extra cash to have them do it.

Gary

 

[BkerChuck]

Glad you found your electrical problem even if it was self induced.

When I did my CB4ooF I had the tank resealed with a product called Red-Kote. It was recommended to me by a local restoration shop that does a lot of Indian motorcycles. Unlike the old school Kreem treatment you don't have to etch the inside of the tank first. Had it done about 5 years ago and still looks great. Of course I also try to only use non-ethanol gas in that bike as much as possible.

 

[garyahouse]

Thanks for the input... at the moment the tank is on the bike and the bike is at Action Honda in Hudson, Fla. They won't be able to run it with the gas tank like it is. The petcock is clogged as well. UGGGH. It never ends, it seems. Probably need to get up there and retrieve the gas tank on Tues when they open BEFORE they get into the bike. At the moment it's waiting "in line" as they're pretty busy.

Gary

 

[Geezer]

Regarding the clutch, does it have a clutch cable? If so, did you verify that the cable is not the problem?

 

[BkerChuck]

Gary,

That petcock should be available from David Silver spares. Be aware though, Honda made a change to the intank filter that fits on the petcock. I changed my filter and started having issues. Full tank, turn fuel on and start bike. Only ride a few miles, like about 5, and it acts like it's starving for fuel. Switch to reserve and it runs fine. Somewhere along the line Honda shortened the filter length and it would suck down into the fuel tube and shut it off. I disassembled mine and cut about 1/4" off the fuel tube and it's been fine ever since. I now have more regular tank and less reserve but I don't use this as a daily rider. Clutch cable may need removed and lubed up if the bike sat very long. The clutch itself on those little 4 cylinders is not usually a hard pull.

Good luck,

.

 

[mech 1 twa]

How is bike running?

Always clean out tank after carb. rebuild. All that dirt goes back into clean carbs. and causes more problems.

Don't ask me how i know. 78 Honda cb400A Different bike than yours. Twin 400 2 speed semi-auto. No clutch.