Got my GS850 to fire but doesn't stay running ....

[Anonymous]

Got my GS 850 to run a few times for a just seconds ... almost acts like it isn't getting gas ..... and then it seems like the spark isn't hot enough ...
Oh well I will keep working with it ..... hopefully I can get it tomorrow after work ...

Well this is a trek .. learning how these bikes work ..
Don't understand why it wants to start but doesn't --

The plugs appear damp though

GD

[earlfor]

First off, what year is the bike? How long was it sitting up when you got it?
What have you done to it since you have had it? Do you have a manual of any kind for it? How many miles on it? Have you replaced anything on it such as battery, switches, wiring, oil filter, air filter, crankcase oil, gas in the tank, etc etc. Give us a little background info on it and we'll see what we can do. :-)

Earl

[Anonymous]

... has set about 3 years ... I haven't changed anything yet

... I haven't changed anything yet ... but it keeps blowing fuses for some reason (starter fuse and one other) ... then all of sudden it will let me try and start it .. acts like it really wants to start but doesn't keep running ...

It is a 1981 GS850G ... I just got it .. I have no manual ... I did dump the old gas out .. and put new in it ... it is a solid, nice looking bike ...

one question .... is an ignition switch getting worn and going bad a COMMON problem ? The bike has 21,000 on speedometer ... don't know if it is original or not ..

Thanks much ..
Real bike rookie,
GD

[earlfor]

Re: ... has set about 3 years ... I haven't changed anything

OK then. First thing we need to do is fix whatever is blowing fuses. Cause it aint a gonna run if'n it cant get no lecktricity. :-)

corrosion increases resistance and you end up drawing excessive current through the fuse trying to get enough to run the electrical device. Clean the battery terminals, check battery voltage, remove the gas tank, check all the connectors including the clips on the wires to the coils. Unbolt your fuse box and open the back of it. Inside you will see the internal connections to the fuse holders. These normally do not get serviced and are corroded. Pull apart all the plugs you find in the harness and check them for corrosion. clean them as needed. Coating them in electrolytic grease is a good idea. If you dont have any, vaseline will work fine, it just will not last as long. Check the ground wires on the bike's frame wherever you find them. There is a main one on top of the transmission case beneath the carbs. Once you have cleaned all the electrical connections, you should be able to check battery voltage with a multimeter to get a base reading, then check voltage at the coil + terminals to compare.

Whenever trying to get an unknown bike running, it is best to start at the beginning and make no assumptions. Assumptions just come back to bite you in the butt halfway through the refurbishing/setup process. :-)

The first thing you must have is a good electrical system. Without that, nothing will work right, including the engine.

Earl

... I haven't changed anything yet ... but it keeps blowing fuses for some reason (starter fuse and one other) ... then all of sudden it will let me try and start it .. acts like it really wants to start but doesn't keep running ...

It is a 1981 GS850G ... I just got it .. I have no manual ... I did dump the old gas out .. and put new in it ... it is a solid, nice looking bike ...

one question .... is an ignition switch getting worn and going bad a COMMON problem ? The bike has 21,000 on speedometer ... don't know if it is original or not ..

Thanks much ..
Real bike rookie,
GD

[Anonymous]

Whatever you do, don't use starting fluid!

Evil stuff.

Take the carbs off, take the bottoms of the bowls off and you'll see a screw in the middle. Take that off and make sure you can see down it. If not, there is probably some gum in there and you'll need to get that out with a pipe cleaner. Just clean everything really well while your in there and make sure the floats move nice and freely.

[Anonymous]

wow!! ... what awesome advice !!!!! ....

Guys!! ... you are awesome .... thanks soooo much .... I can't wait to get off work !!!!!

(I will put the starting fluid can away too- )

Sure makes sense ... to make NO assumptions .... only thing that bothers me is when I "wiggled" the key it "lit" up once ... maybe the ignition switch is corroded too ..... huh?


I will stop by the parts store and get some of that electric "lube" stuff ....

I will work on those carbs too ,,,

Thanks many times!
GD

[earlfor]

Re: wow!! ... what awesome advice !!!!! ....

Yepper :-) ignition switches are notorious for collecting water/corrosion.
....and there ya go, you're trying run with a dirty diaper. :-)

Earl

[quote="gdtractor"]
only thing that bothers me is when I "wiggled" the key it "lit" up once ... maybe the ignition switch is corroded too ..... huh?

[Anonymous]

Got electric straighten out some--but where do hoses go....

Got the 850 to run ... but still won't stay running ..

I had to unhook the starter and the blowing fuses stopped. I cleaned the other connections ....

When I turned it on ... the "dash" lit up like a Christmas tree!!

I turned the bike on .. on ... and hooked up an external battery to the starter .... I got it started and "reved" it up some .. only have it act like it ran out of gas ....

I held my hand over the intake on the carb ... it would start and run .. for a minute and even accelerate ... only to "fizzle" as if .. not to get gas.

I know I have to start again ... on the electric ... but one question on the hoses from the carbs ...

There are 4 hoses. One is obviously hooked to the "fuel-cock". One I have hooked to the fuel-cock along side of the "main" fuel hose---this hose is run to the front of the carbs. 2 hoses that are on the rear of the carb above the intake mouth are not hooked to anything---

Also ... there is an electrical wire run to a unit 5 inches or so from the fuel cock with a metal nipple ... I don't know which hose goes there either ... (help!--

Thanks much .... (at least I am starting to learn .. ) ...

gdtractor

[Anonymous]

.. further note: gdtractor's 850

..... I have to turn the fuel cock to "reserv" to get gas to flow ....

.... and at times ... it appears gas seeps out the back (or intake mouth) when it dies .... as excess gas ..... (maybe it is not getting thru huh?

gd

[earlfor]

Re: .. further note: gdtractor's 850

There isnt any intake mouth on the fuel petcock. The small line is the vacuum line which actuates a diaphram to open the fuel valve. The large line is the fuel line which gets connected to the carb Tee. If the petcock is seeping fuel in any place, its time for a new one. Try putting the end of the vacuum line in your mouth and sucking on it. It should take about 1 lb of draw to activate the petcock diaphram and let fuel flow. (remove the fuel hose from the petcock so you can see the fuel flow) If fuel does not flow, then the petcock is a goner. If you get any gas in your mouth, the diaphram is leaking, and the petcock is a goner. If it takes more vacuum to operate the petcock than it takes to drink a coke through a straw, the petcock is a........YEP...... GONER. :-)

Earl

..... I have to turn the fuel cock to "reserv" to get gas to flow ....

.... and at times ... it appears gas seeps out the back (or intake mouth) when it dies .... as excess gas ..... (maybe it is not getting thru huh?

gd

[Anonymous]

Petcock not leaking ..

Hi Earl
The petcock isn't leaking. But I am not sure I have the correct vaccuum hose hooked up. On the back of the carb the gas hose goes on the Tee--then above this hose are 2 hoses .... are they not hooked to anything (presently) ......

which hose hooks to the diapham like device in front of the petcock that has the wire run to it ..

Thanks so much Earl for your help .. I hope I can describe it correctly ...
GD

[earlfor]

Re: Petcock not leaking ..

Hi Earl
The petcock isn't leaking. But I am not sure I have the correct vaccuum hose hooked up. On the back of the carb the gas hose goes on the Tee--then above this hose are 2 hoses .... are they not hooked to anything (presently)
******************* . gas to Tee is correct. The only hoses I can think of that would be above the Tee are vent lines for the carbs. Those vent to atomsphere.

which hose hooks to the diapham like device in front of the petcock that has the wire run to it ..
******** I believe that would be your fuel tank vent line. It doesnt hook to anything, its a vent.**********


When you remove the fuel line from the petcock and suck on the vacuum line, do you get fuel flow out of the petcock?

E.



Thanks so much Earl for your help .. I hope I can describe it correctly ...
GD

[Anonymous]

... I am kind of slow .. I think I know what you mean ..

Earl
The main fuel line ... I should unhook .... then take the smaller hose next to it ... unhook it and suck on it ... and see if I get gas?

I will try this tomorrow ... but do I have it correct?

and the diaphram like mechanism with the wire run to it on the gas tank in front of the petcock ... does not have a hose that runs to it? Correct?

Thanks
GD

[earlfor]

Re: ... I am kind of slow .. I think I know what you mean ..

Earl
The main fuel line ... I should unhook .... then take the smaller hose next to it ... unhook it and suck on it ... and see if I get gas?
**************yes. with the small hose still connected to the petcock and disconnected from the carb vacuum fitting, sucking on the small line should cause gas to flow from the large (fuel) outlet on the petcock.

I will try this tomorrow ... but do I have it correct?



and the diaphram like mechanism with the wire run to it on the gas tank in front of the petcock ... does not have a hose that runs to it? Correct?
The wire goes to the gas guage and the hose connected to it is a vent. The other end of the hose does not connect to anything.

Earl

Thanks
GD

[Anonymous]

thanks much...

... when I do this Earl ... the pitcock should not be in the reserve position but on not "prim" (whatever that is) ....

One more thing ... why am I doing this? (please)

Thanks
GD