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Author Topic: Fuel Problem  (Read 1805 times)

Offline Graeme

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Fuel Problem
« on: January 21, 2011, 06:49:14 AM »
Hi All. Well, I got Dexter back with new rings, reco heads etc & managed about 65k's of the 1000k's run in period.

Anyway, today he cut out on me. Waited & started OK but soon cut out again. I filled the tank which took 10 litres. Long story short wa that he kept cutting out, I'd drift to a stop, wait & take off again. Anyway, I found that if I kept to 30k's an hour it was fine & I got home. The fuel filter is 2/3rd's full & seems clean.
I haven't investigated further as I had to take the car then to my appointment.

Anyway, I had done about 20k's at suburban speed before I took it up to about 80 for about 10k's. It was about 500 metres back to suburban speeds when the trouble started. I could go for about 500 metres at 80k's before it cut out. It certainly seems like fuel starvation.

I'll have a look in the morning but ay thoughts would be appreciated.

Thanks
« Last Edit: January 21, 2011, 06:50:02 AM by jibbonpoint »
1985 R65 LS

Offline Bob_Roller

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Re: Fuel Problem
« Reply #1 on: January 21, 2011, 07:27:09 AM »
There should be a filter screen over the fuel tap intake tubes .

You may want to drain the tank and have a look at the screen .

Other remote possibility is the tank isn't venting, the tank somehow vents through the fuel cap .

Try riding with the cap loose and see if it makes any difference .
'81 R65
'82 R65 LS
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!

Offline Rob Valdez 79 R65

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Re: Fuel Problem
« Reply #2 on: January 21, 2011, 04:41:13 PM »
Did you remove a float bowl to check for water?  (Just guessing here, Bob's advice is better!)

Offline nhmaf

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Re: Fuel Problem
« Reply #3 on: January 21, 2011, 05:34:40 PM »
+1 on Bob's suggestions, then Rob's.

Also, just for grins, recheck that your spark plug leads have proper continuity/resistance.  I had a cap once that would work fine until it got hot from sustained engine running, at which point it would break the connection to the plug.   Do the plug electrodes in both cylinder look the same?  If one is very whitish in color while the other is tan, the white side is running too lean.
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Vegasrandall

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Re: Fuel Problem
« Reply #4 on: January 21, 2011, 08:38:15 PM »
If you have point style ignition it might be a wormy condenser

Offline Semper Gumby

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Re: Fuel Problem
« Reply #5 on: January 22, 2011, 03:59:58 PM »
+1 what everybody else said and have you replaced the "crack-o-matic" grey coil yet?  I have a lovely DYNA on mine.  Might be the coil....
Bill Gould ?1980/03 R65 When at first you don't succeed....Moo!

Offline Lucky_Lou

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Re: Fuel Problem
« Reply #6 on: January 23, 2011, 06:19:17 AM »
Quote
There should be a filter screen over the fuel tap intake tubes .

You may want to drain the tank and have a look at the screen .

Other remote possibility is the tank isn't venting, the tank somehow vents through the fuel cap .

Try riding with the cap loose and see if it makes any difference .
+1  did you try it on reserve both mine blocked due to debri before i fitted a small mesh filter inside the tank i did put some photos up of this long time ago.
Lou  
Ask questions later

Offline Bob_Roller

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Re: Fuel Problem
« Reply #7 on: January 23, 2011, 12:16:53 PM »
I assumed that your owning an '84 LS, that it would have a Karcoma fuel tap .

The Karcoma taps have a metal screen over the fuel intake tubes and the barbed fitting that the fuel line goes onto points to the rear .

Remote possibility that you may have a Germa fuel tap .

The Germa taps don't have a screen over the intake tubes, they have a plastic screen incorporated into the barbed fitting and nut that the fuel line goes onto .

The Germa taps have the fuel line coming out at the 6 o'clock position, also the Germa taps have a small screw securing the selector handle , the Karcoma taps don't have this .


http://www.realoem.com/bmw/showparts.do?model=0365&mospid=51899&btnr=16_0225&hg=16&fg=05


http://www.realoem.com/bmw/showparts.do?model=0365&mospid=51899&btnr=16_0245&hg=16&fg=05
« Last Edit: January 23, 2011, 12:21:56 PM by Bob_Roller »
'81 R65
'82 R65 LS
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!

Offline Graeme

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Re: Fuel Problem
« Reply #8 on: January 23, 2011, 02:53:47 PM »
Thank you for all of that. I didn't get the chance to check it out over the weekend so I hadn't any feedback to provide. I'll buy some fuel containers today to siphon the fuel into & get to it this week.

I think that it's worth my while to schedule a complete checkover including the electronics so to avoid (as far as possible) any more surprises.

The mechanic that supplied the top end reco suggested that I dismantle the handlebar switches & clean them. He suspected that there was dust within. I guess I'll start there & work towards the exhaust.

It looks like it is indeed the Karcoma fuel tap, from the outside, Bob.
1985 R65 LS

Offline Graeme

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Re: Fuel Problem
« Reply #9 on: January 23, 2011, 11:37:14 PM »
Another question & probably a stupid one; I turned on the fuel tap & loosened the fuel filler cap which made no discernable difference to the fuel level in the clear plastic fuel filter bowl. The motor was turned off & hasn't been started for about three days. I would have thought that there would have been some flow after that time?
1985 R65 LS

bruce_launceston

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Re: Fuel Problem
« Reply #10 on: January 24, 2011, 02:51:20 AM »
If you want to check if the fuel is running to/through the carbies hold the fuel bowl and flick the wire retainer off, then crack the fuel bowl loose. The fuel will flow and fill the bowls and then overflow.

Offline Graeme

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Re: Fuel Problem
« Reply #11 on: January 26, 2011, 01:38:11 AM »
Well, did that & the fuel flows freely through the a) tap & b) fuel filter.

I pulled out the plugs & the left was "normal" but the right was carbon fouled as per the Haynes manual spark plug condition chart.

Checked the gap & both were 0.6mm.

It's done 64K's since the top end reco.

Looks like it's back to the shop. :(
1985 R65 LS