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Petrol dripping on the floor

Started by ELIMINATOR, August 26, 2012, 12:20:35 PM

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ELIMINATOR

typical, put the new front sprocket on. Fiy Randys spin on oil filter adaptor. Run the engine up, petrol dripping.

Time to drain the float bowls, see if that flushes any shit out from the seat.

Would it be of any use to turn of the petrol tap, drain the floats, then pump will have to prime the float bowls, that might remove any debris on the offending seat?
Assuming a float hasn't gone AWOL
BMW 1150GS
Moto Guzzi California 3

FJmonkey

Quote from: ELIMINATOR on August 26, 2012, 12:20:35 PM
typical, put the new front sprocket on. Fiy Randys spin on oil filter adaptor. Run the engine up, petrol dripping.

Time to drain the float bowls, see if that flushes any shit out from the seat.

Would it be of any use to turn of the petrol tap, drain the floats, then pump will have to prime the float bowls, that might remove any debris on the offending seat?
Assuming a float hasn't gone AWOL
Yes, having fuel rush in to the bowls may wash out any crap stuck at the seal. A gentle knock on the bowls has also been known to help as this gives a light jolt to help move things. A wood dowel and something light to use as a hammer. Like causing some light vibration, don't go Thor's Hammer on it.
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

ELIMINATOR

Thor's hammer, damn, ruined my fun. :crazy:
BMW 1150GS
Moto Guzzi California 3

ribbert

I rode with this problem for a couple of years.  I carry a 300mmx10mm length of steel rod with me to tap the offending carby, you can identify which carb by tracing the leaking overflow tube back.  Until I o'hauled the carbs this happened dozens of times, often while riding, at no fixed interval.  I would recommend steel because wood is too soft and dulls the blow, it's the sharpness of the tap that does the job not the force.
Noel
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

Pat Conlon

To identify the offending carb, I've numbered the tips of the choke vent hoses to correspond to the carbs (with the number tape used on spark plug wires) That way when I see gas dripping from number 2 hose, I know to go after number 2 carb.

Cheers
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
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3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
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bigbore2

A cheap simple way to prevent this is to put an inline petrol filter on.  Mine is on the single line coming from the tank before it splits.  Don't put a filter for a lawnmower or small engine on as it probably will not flow enough in WOT or high rpm runs. Randy has some filters.

ELIMINATOR

I replaced the petrol filter yesterday with one bought from Randy.  :good2:

Can the carbs be reached to tap them with a length of metal, without removing the tank or heat shield?
BMW 1150GS
Moto Guzzi California 3

ELIMINATOR

 I've identified is as No. 2, that is 2nd carb in from the right, when sat on the bike.

I've tried tapping the carb, not easy to access the float chamber area though.

Turned petrol off, ran it for a while, petrol pump  was gasping :biggrin: then turned petrol tap back on, still leaked.

Then I tried chocking the bike, by revving it to about 6,000, then shoving a sponge over the intake, the idea behind this, is that as it can't suck air, it would perhaps try to suck more petrol. Did this a few times, still leaked.

Then I blew down the overflow pipe with the engine stopped.
Then I tried blowing down the overflow pipe with the engine running.

I didn't give it long after I had finished this, but, it had stopped leaking. Engine was a bit hot.

Not convinced that I've cured it though. :scratch_one-s_head:
BMW 1150GS
Moto Guzzi California 3

ribbert

Quote from: ELIMINATOR on August 28, 2012, 05:18:20 AM
I've identified is as No. 2, that is 2nd carb in from the right, when sat on the bike.

I've tried tapping the carb, not easy to access the float chamber area though.

Turned petrol off, ran it for a while, petrol pump  was gasping :biggrin: then turned petrol tap back on, still leaked.

Then I tried chocking the bike, by revving it to about 6,000, then shoving a sponge over the intake, the idea behind this, is that as it can't suck air, it would perhaps try to suck more petrol. Did this a few times, still leaked.

Then I blew down the overflow pipe with the engine stopped.
Then I tried blowing down the overflow pipe with the engine running.

I didn't give it long after I had finished this, but, it had stopped leaking. Engine was a bit hot.

Not convinced that I've cured it though. :scratch_one-s_head:


What are you tapping the carby with?  A 12" piece of steel rod will easily reach and the bowls should be the most accessable part of the carb, just pull the heat shield down a tad with your finger.  If you using wood it's unlikely to work. It needs a sharp, not hard, tap.  It's most likely a sticky needle and therefore works better if you drain the bowl, just back off the screw in the bottom of the bowl, also easily accesssable., I became so proficient at this on the road I never bothered to fix it for 40k. Sometimes it would happen at 3 or 4 times a day and sometimes go for 5,000 k's or more.  The eventual fix was a thorough carb clean.

Noel
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

ELIMINATOR

Thanks for the tip.

Compared to my Yamaha XJ900S Diversion, the carbs are a pain to reach.

Were they called Seca in the USA? It's a 1998 shaft driven, air cooled 4 cyclinder.
BMW 1150GS
Moto Guzzi California 3