dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
26399
share rss forum feed


chmod
Premium
join:2000-12-12
Lockport, IL

1 edit

Help troubleshoot snowblower carb problems.

Click for full size
I bought a used Dynamark model 5360-6200 snowblower last year, unsure of age. Toward the end of last winter I came out to the garage for something and it smelled like I tipped a gas can over or something. After some investigating I found the source of the leaking gas was coming from the carb of the snowblower. I took the bowl off along with the float and jet quickly examined them, didn't find anything, and put it back together. No more leaks until a few weeks ago same thing. I took it apart this time and inspected the float to make sure it wasn't taking on gas and it is infact air tight. I don't really know what problems to look for on the jet it appeared ok to me. I them reassembled it all again this time it lasted about 3days before emptying the remainder of the gas in the tank onto the garage floor. Attached is a picture of where its leaking the butterfly valve I think its called it spews from there. Any ideas?

edit:
I believe the motor is a 5hp tecumseh.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.


PoloDude
Premium,VIP
join:2006-03-29
Northport, NY
kudos:3
One thing i would do is install an in-line shut off valve. That will stop the leaking if you can't fix the carb. Does it still run ok?


GadgetsRme
RIP lilhurricane
Premium
join:2002-01-30
Canon City, CO

1 edit
reply to chmod
I'm not sure about that particular model, but most snow blowers are gravity feed on the fuel. There should be a fuel shut off at the bottom of the fuel tank that should be turned off every time you shut the blower off. The fuel, if it is coming out of the butterfly of the carb, which is the choke, is flowing internally from gravity pressure.
--
Gadgets


chmod
Premium
join:2000-12-12
Lockport, IL
reply to PoloDude
said by PoloDude:

One thing i would do is install an in-line shut off valve. That will stop the leaking if you can't fix the carb. Does it still run ok?
That was going to be my plan of attack if I couldn't get it to quit. The last time I put it back together a few days ago I played with the jets until it ran smooth. So yea it does run really good. Last winter it would only stay running if I left it fully choked hence running really rich and not making much power. I knew when I was about to run out of gas because it kicked into over-drive because it leaned out and really threw the snow. Now I've got it to where it will run really well with the choke all the way off.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.


chmod
Premium
join:2000-12-12
Lockport, IL
reply to GadgetsRme
Click for full size
said by GadgetsRme:

I'm not sure about that particular model, but most snow blowers are gravity feed on the fuel. There should be a fuel shut off at the bottom of the fuel tank that should be turned off every time you shut the blower off. The fuel, if it is coming out of the butterfly of the carb, which is the choke, is flowing internally from gravity pressure.
You would think so, not on this one.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
reply to chmod
I had a gas trimmer (weed eater) with that problem. It would spill a bunch of gas on the ground overnight and flood the engine. Ran fine once it got started, but if you stopped it and let it sit for about an hour the engine would be flooded with gas again.

Not sure exactly what was wrong with it though, it was under warranty so I didn't mess with it.


PoloDude
Premium,VIP
join:2006-03-29
Northport, NY
kudos:3
reply to chmod
I think a shut off valve is your easy course of action. I have one on my snowblower and generator.


chmod
Premium
join:2000-12-12
Lockport, IL
said by PoloDude:

I think a shut off valve is your easy course of action. I have one on my snowblower and generator.
Yea, I think thats the route I'll go. Shut the gas off let the remaining fuel burn out park it. Was just trying to find an explanation for it randomly doing this.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
reply to chmod
There is a problem with either the float, its needle or seat.

I agree that a shutoff is a great idea, but the current problem still needs to be fixed.
--
Striving for Parfection.


Tursiops_G
Technoid
Premium,MVM
join:2002-02-06
Norwalk, CT
kudos:1

1 edit

1 recommendation

reply to chmod
said by chmod:

Yea, I think thats the route I'll go. Shut the gas off let the remaining fuel burn out park it. Was just trying to find an explanation for it randomly doing this.
Explanation: Dirty/Worn Needle Valve/Seat, or Sticking Float in the Fuel Bowl...

Go with the Shutoff Valve (Simple, Cheap), or else have the Carb rebuilt (Higher Cost)...

(Edit: Cho Baka See Profile beat me to it).
-Tursiops_G.
--
If You're Unsure, "RTFM"... If You're SURE, "RTFM" Anyway.


chmod
Premium
join:2000-12-12
Lockport, IL
reply to Cho Baka
said by Cho Baka:

There is a problem with either the float, its needle or seat.

I agree that a shutoff is a great idea, but the current problem still needs to be fixed.
The float appears fine, it has no leaks, nor varnish. What do I look for on the needle? Theres a spring I guess you would call it and I assume is the seat on the bottom side.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.

Stevert

join:2001-10-23
Algonquin, IL
said by chmod:

The float appears fine, it has no leaks, nor varnish. What do I look for on the needle? Theres a spring I guess you would call it and I assume is the seat on the bottom side.
The float could be fine, but if the needle isn't sealing it won't shut off the flow of gas into the carb.

And no, the seat is actually above the pointed top of the needle. When the bowl fills with fuel and causes the float to push the needle up, that's where it seats. Look for damage/contaminants there and on the needle point itself.

Here's a link to a picture of a carb assembly that shows the seat - It's a downdraft carb, and yours is a side draft, but the float/needle/seat work the same in both:

»racingarticles.com/images/carb_basics.gif


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
Reviews:
·TekSavvy DSL
reply to chmod
There is sometimes a specification for the weight of the float.

Aside from that, make sure that nothing is sticking and that the sealing surfaces of the needle and seat are good.

Clearly something isn't good!

Sometimes you can buy rebuild kits, these may include a float/needle/seat.

If it is dirty, then make sure to address the source of the dirt as well, or the problem will recur.
--
Striving for Parfection.


Tursiops_G
Technoid
Premium,MVM
join:2002-02-06
Norwalk, CT
kudos:1
reply to chmod
Just adding to Cho Baka See Profile's post, Is there any Rust in the Fuel tank? If So, then you should either replace the tank, or else add an In-line Fuel Filter to prevent the rust from re-contaminating the carb...

-Tursiops_G.
--
If You're Unsure, "RTFM"... If You're SURE, "RTFM" Anyway.


chmod
Premium
join:2000-12-12
Lockport, IL
reply to chmod
What numbers do I reference to buy a rebuild kit? I'm pretty sure I can get a rebuild. I thought I googled some numbers on it to confirm it was a tecumseh last winter. Nothing I input now reflects that.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.


chmod
Premium
join:2000-12-12
Lockport, IL
reply to Tursiops_G
said by Tursiops_G:

Just adding to Cho Baka See Profile's post, Is there any Rust in the Fuel tank? If So, then you should either replace the tank, or else add an In-line Fuel Filter to prevent the rust from re-contaminating the carb...

-Tursiops_G.
The tank is very clean.
--
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs.


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
reply to chmod
For parts, I would go via the manufacturer of the snowblower, or a decent sized small engine repair shop.
--
Striving for Parfection.

gawron

join:2005-12-09
Pontiac, MI
reply to chmod
Rebuild kits are cheap and fairly easy to install. Sounds like a sticking float valve and a rebuild kit will cure that problem. Rebuild it, you'll be happy you did!


DaHen
Premium
join:2002-11-08
Brockton, MA
reply to chmod
I vote for a rebuilt kit as well. The new gaskets and needle would help.
Plus a fuel filter and valve.


HRM
God Bless America
Premium,MVM
join:2002-02-03
Darien, CT
kudos:1
reply to chmod
Fast and priced well.

»www.jackssmallengines.com/index.html

Call if you need help.

impalass1369

join:2007-09-11
Mercier, QC
reply to chmod
You need a new needle valve and seat.


Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18
reply to chmod
 
Click for full size
I'd say the float is too heavy. If it is made from brass then it has likely leaked at the seams and it would have gas inside it, or if it is solid material then the body has absorbed gas making it heavy.

There is a float scale made that is used to determine it's weight.

Tomco Carburetor Float Weight Scale #13700 13.95 + 5.00 shipping
»cgi.ebay.com/ebaymotors/Tomco-Ca···40154759

You can also try local parts stores to get one. You would need to know the correct weight of your float also.

»www.trialspartsusa.com/diagrams/···2000.doc
quote:
The reasons for a float going bad are varied, but I will mention a few of the common problems. Trials machines often sit for long periods and gasoline will eventually permeate the float making it unable to lift the gas needle valve. Some fuels appear to cause premature failure of the float materials. I suspect that the grain alcohol found in some gasoline brands is a common culprit. If a machine is going to be stored for a long period, it is best to drain the fuel from the tank as well as the float bowl. Note: Simply allowing a float to dry may return it to it’s proper weight, however the float remains permeable and must be replaced. If a float (or floats) is bad, the richer mixture coming into the engine will cause poor running. The operator may mistake this problem as being caused by the gas jets. The operator or his/her mechanic may change the gas jets to ones that are “leaner” to compensate for the rich condition. This is not a good solution as the correction only applies to the engine when it is running at low revolutions. As revolutions rise, the carburetor requires more fuel and the engine will quickly use all of the excess gasoline that is in the float bowl.
»www.cheapsnowblowerparts.com/pro···C76.html
quote:
AMF primarily produced lawn equipment under the name Dynamark. This trade name now comes under the Murray corporate banner.
Normally you do not store a gravity fed engine with gas in it, but you run it dry instead before storing it. Alternatively, you can install a fuel shutoff at the tank base.

Regards,

Doctor Olds
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?


Splitpair
Premium
join:2000-07-29
Cow Towne
kudos:3

1 edit
reply to chmod
Click for full size
said by chmod:

The float appears fine, it has no leaks, nor varnish.
Is it brass? If so shake it if it's empty it's good if it's composite don't worry about it

What do I look for on the needle? Theres a spring I guess you would call it and I assume is the seat on the bottom side.
Carefully examine it at the tip for any scoring varnish or discoloration.

The seat is the part the needle sets into you may be able to use a bright light and mirror to examine it without removing it from the engine again your looking for any damage or varnish.

If you find discoloration or varnish on either the needle or the seat try removing it with some lacquer thinner and or acetone.

If the needle is damaged it will need to be replaced if the seat is damaged in most cases such as with the Walbro or Nikki carbs the body will need to be replaced as the seat is not removable.

As for parts these folks have great pricing and ship quickly. »www.ordertree.com/

Wayne
--
If you cannot fix it with a buttset and some beanies you ain't a technician.

wbertram
Premium
join:2005-08-19
Allentown, PA

3 edits
reply to chmod
Most carbs like this have a fuel bowl with a drain valve on the bottom. If the rubber washer that seals this valve is old, worn, torn, the drain valve will leak.

Locate the drain valve and check the condition of the rubber washer.

You can also drain the bowl using this valve. Then check later and see if there is additional fuel in the bowl. If there is, the float/needle valve are leaking.

fixrman
Premium
join:2003-02-10
Hatboro, PA
Reviews:
·Verizon FiOS
reply to chmod
The float is likely sticking or the needle which shuts off fuel flow to the bowl will not seat.

When a gasoline-powered small engine sits for a long period of time, fuel in the bowl dries and solidifies into a varnish. The amount of varnish buildup depends on the amount of fuel present. It is always best to run a lawn mower or other yard tool completely out of fuel before storing.


Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18

1 edit

1 recommendation

reply to wbertram
said by wbertram:

Most carbs like this have a fuel bowl with a drain valve on the bottom. If the rubber washer that seals this valve is old, worn, torn, the drain valve will leak.

Locate the drain valve and check the condition of the rubber washer.
Not the issue. Look closely at the image the OP posted. You can see the fuel pouring out of the throat of the carb right by the butterfly valve. The fuel is coming out from the bowl overfilling as fuel keeps coming in past the needle and seat which the OP said that those are good after checking them. That leaves the float having become gas loaded making it heavier than it should be keeping the needle off the seat allowing fuel to flood the bowl and then to flow out the carb throat. Brass or composite floats can both become logged with gas and end up being heavier than they should be which will keep the needle off of its seat allowing the gravity fed fuel bowl to drain the tank as it pours fuel out the carb throat.

said by wbertram:

You can also drain the bowl using this valve. Then check later and see if there is additional fuel in the bowl. If there is, the float/needle valve are leaking.
Since the bowl is gravity fed, draining the bowl will do nothing as the tank will refill it by gravity when the float drops opening the needle off its seat. Doesn't serve a purpose to drain the bowl when it isn't the problem and it isn't leaking.
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?


Splitpair
Premium
join:2000-07-29
Cow Towne
kudos:3
reply to Doctor Olds
said by Doctor Olds:

You can also try local parts stores to get one. You would need to know the correct weight of your float also.Regards,

Doctor Olds
Therein lies the problem I have a couple dozen small engine manuals covering most every air cooled engine used in this country since the 70's and in none of them is the weight of the float specified.

FWIW I have rebuilt maybe 100-150 small engine carbs and have never come across found a defective float.

Wayne
--
If you cannot fix it with a buttset and some beanies you ain't a technician.

Abuswrench

join:2003-11-05
Bedford, OH

1 recommendation

reply to chmod
Also check your fuel line. The old rubber breaks down and very small pieces will get between the needle and seat. I've had/seen this problem a few times. Always with OLD fuel lines. From the pictures, yours is painted = original. Hope this helps. jd


Piggie
I Actually use Windstream
Premium
join:2005-11-23
Orange Springs, FL
Reviews:
·Windstream
·HughesNet Satell..
reply to Splitpair
Wayne, I have rebuilt a few dozen carb and have seen one bad float. Normally it's the needle valve.

My general advise is any small engine should have a fuel filter and if gravity feed a cutoff. I add them to any engine I have. I recently bought a Briggs generator. It had a shut off, but not a filter.

I also shut down the engine with the shut off valve if it will be put away for more than a few days. I am sure this cause some lean burning toward the end, but I ride the choke, increasing it to minimize this effect. I don't think this tiny bit of lean running hurts anything and it empties the bowl. I have Briggs engines around here that have run 10 years between carb cleaning or rebuilds doing this.

Another problem I am seeing, a lot of the newer plastic ventless red plastic gas tanks for storing fuel, don't have even a primitive filter in their spouts. They also don't seal very well, as I have found dirt and water in them from being stored outside, that wasn't their before. Sadly I can't find the old style 5 gallon cans I used to buy.
--
| Speedstream 4200 Modem - 3m/384 plan | W98-W2KSP4-XPSP2 - All AMD | Buffalo WHR G54S with Tomato 1.18 | 3 downstream switches feeding 6 total clients (no wireless) | Including the Data port on the side of my neck |


Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18
reply to Splitpair
said by Splitpair:

FWIW I have rebuilt maybe 100-150 small engine carbs and have never come across found a defective float.
From a Sears riding lawn mower.



--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?