Ducati Monster Forum

powered by:

February 24, 2025, 03:59:28 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Please Help
 
   Home   Help Search Login Register  



Pages: [1]   Go Down
  Print  
Author Topic: Leaking FCR41!!!  (Read 1837 times)
671M900
Sr. Member
****
Offline Offline

Posts: 378


« on: December 17, 2010, 10:53:13 PM »

 Huh?

So, when ever I leave the vfuel valve open, or when the bike is running, I notice a leak in the left FCR41, the one with the accelerator pump. It's not the fuel bowl gassket, it's the section above it, where there's that little button head hex screw. Not sure if it comes apart, but would like to try to seal this leak. There are no cracks that I can see, and non around it, it just seems to be leaking, and only in that carb.

It's the one above the sudco sticker, but under the FCR41 sticker:

Logged

671ducati.wordpress.com Record of Progress!
Howie
Post Whore
******
Offline Offline

Posts: 17370



« Reply #1 on: December 18, 2010, 08:53:15 AM »

Coating the area with aerosol powder will help pinpoint the leak.  You could then try cleaning the area real well and coating it with a gas and ethanol resistant epoxy.  Might work, might not, worth a try.  Way back GM was doing this with porous transmission cases on warranty.
Logged
koko64
Post Whore
******
Offline Offline

Posts: 15746


« Reply #2 on: December 18, 2010, 02:16:15 PM »

G'day.
Some questions.
Are you running a float bowl overflow hose from the outlet? The outlet is up high between the carbs and when the bike is on the side stand it leaks over that area if you don't have a hose.

Do you here a hissing sound with the bike turned off after running and the fuel tap still open? Is it just the left carb with the accelerator pump? If the answer is yes it's probably an accelerator pump overflow.
I have an overflow hose and this kind of leak bypassed it when my accelerator pump flooded rather than the the float bowls. Give that pump arm a wiggle and spray the area with WD 40. Clean the pump parts and leak jet/fuel return circuits with brake cleaner. That little pump reservoir is an area for dirt and fuel varnish/gum to collect. The bleed circuits are small.

Gunk can keep the return circuit open. I could hear the pump squirting fuel into the carb by it's hissing sound as it hit the hot carb/manifold area. You would think there was a cobra under the tank. This was with the bike sitting there turned off. It appeared as if the pump got pressurized with fuel from the float bowl. The float bowls weren't flooding.

I had to change my oil as it was contaminated from the pump pissing down the carb all night. Because it was a pressure overflow situation only the rear cylinder got full. I had to remove the plug to clear the compression lock.

Another possibility is a slow weep from the bowl drain plug. The drain plugs warp easily if you are heavy handed or pinch an O ring. There was condensed fuel on the areas higher than the initial weep in the cold weather. This is unlikely.

So carb cleaner to the suspected areas and turning off the fuel tap when parked are important.

Cheers and have a great Christmas.
Logged

2015 Scrambler 800
671M900
Sr. Member
****
Offline Offline

Posts: 378


« Reply #3 on: December 18, 2010, 05:29:03 PM »

Positive it's not the fuel drain.

I've already confirmed it was that area, no need for aerosol powder. After running, that area has fuel coming out of it, even immediately after wiping it off.

I don't notice a hissing sound, but I always try to make it a point to shut off my fuel tap, however, it takes awhile for whatever is leaking to stop.

Will go for a ride to check and see what happens afterwards.
Logged

671ducati.wordpress.com Record of Progress!
devimau
Jr. Member
**
Offline Offline

Posts: 79


« Reply #4 on: December 19, 2010, 10:19:08 AM »

The bowl is attached to the body but this body (with the sudco sticker) is bolted onto the slider body (fcr sticker).
Those 2 bodies are attached by this little hex screws and there's a gasket to seal the 2 parts.
It's obvious that either the screws came loose (very rare) or the gasket went (very rare either), or there's a crack on the body but you'll have to take it apart to find out which one is it.
Be carefull since that gasket is not available in some flat slide models, check with sudco first since if you crack it open and there's no gkt available and the gkt brakes you're in trouble, if you're positive it leaks through that split I'd get a new gkt, replace it and tight those little hex bolts back (if there's no cracks on the body parts) and you should be ok!
Logged
koko64
Post Whore
******
Offline Offline

Posts: 15746


« Reply #5 on: December 20, 2010, 03:53:32 AM »

What Dev said is a possibilty and makes sense, but I hope it's not the case because its more friggin around than the other potential problems. Rebuild verses a clean.

Let us know how you go.
Logged

2015 Scrambler 800
Pages: [1]   Go Up
  Print  
 
Jump to:  


Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!
SimplePortal 2.1.1