# Toro Timemaster surging when idling



## Steely (Sep 24, 2017)

My Timemaster started to develop an engine surge when idling. The machine runs fine when the blades are engaged probably because the engine revs up. But, when I disengage the blades to empty the bag, the engine surges pretty bad.

I have run Seafoam through the fuel system and carb. I have also taken the carb bowl off and it was spotless. I ran a thin wire through the bowl nut jets. I've never changed the fuel filter, but it too looked very clean.

Any ideas what else I can check?

When I first start it up the idle is smooth with no surging, but after running for a while it will surge.

Thanks,

Dan


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## NZONE4284 (Sep 26, 2020)

This happens often. I inject yamalube carb cleaner directly into the carb, using a hypodermic needle with a peice of rubber hose on it. Let it sit for 24 hours it will clean it perfectly! The trick is the yamalube carb cleaner it's amazing stuff. Push as much in there as you can and hook fuel line back up. Start normal in 24 hours. Has never failed me.


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## Steely (Sep 24, 2017)

I was not able to find any Yamalube carb cleaner but a took the carb off the Timemaster and sprayed the heck out of it with standard carb cleaner. Put everything back together and it still surges and backfires when idling.

I'm having a heck of a time finding a replacement carb for the 21199 model on Amazon. Every replacement carb seems to reference the 20199 model. Do they use the same carb? I know the engines are different CC ratings.

Here is an example...

Montree Shop Carburetor for Toro TimeMaster 30" Mower 20199 Briggs & Stratton 8.75 OHV 190cc https://www.amazon.com/dp/B07SMDW2LT/ref=cm_sw_r_cp_api_i_nCdJFb4YAFW3N


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## Vtx531 (Jul 1, 2019)

Idle jet clogged up. I'm not familiar with this carb but it should be pretty easy to remove the idle jet, stick the wire though, spray carb clean, and blow out with compressed air. It sounds like you did the right procedure but just not for the right part of the carb.


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## cityofoaks (Sep 8, 2020)

Verify for yourself but this should be it:

https://www.repairclinic.com/PartDetail/Carburetor/590944/2324561

Always start at Toro, etc... to find part numbers. The engines themselves will be listed as a separate part, then you have the specific engine model number to find engine parts. https://www.toro.com/en/parts/partdetails?id=46588

I assume you checked the other usual suspects.......adjust idle speed, adjust carb, clogged air filter, fouled spark plug, tried non-ethanol gas, etc...... These carbs are not ones that usually have to be junked and replaced completely.


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## Steely (Sep 24, 2017)

Thank you for the input and the links. I have replaced just about everything (spark plug, air filter) except for the fuel filter. But, I did remove that temporarily to rule it out which I did because it was still idling rough without it.

I am not super mechanically inclined but learning. I sprayed the carb, but did not blow compressed air through it. I can't find ethanol free gas near me but have treated it with fuel stabilizer. I'll see about adjusting the idle speed. Maybe I'll take it off one more time and try to narrow down my cleaning to the idler jet.

I tried looking up the 21199 on Toro's website, but couldn't really find the engine model number from that.

Thanks again.


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## massgrass (Aug 17, 2017)

I also have a Timemaster 21199 and the Briggs & Stratton pdf docs point to carb model #590944 with overhaul kit #592172 for a model 140000 engine.


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## Steely (Sep 24, 2017)

Today I took the carb off again and put a wire through every hole I could find on the carb, including the bowl nut injector holes. Sprayed a bit more carb cleaner and blew out the injectors with compressed air. Put everything back together and still have the surging and subtle backfiring.

Is it possible the springs are too stretched out?

Here are a couple of videos displaying the problem...

https://youtu.be/VrjjPYgOyYo

https://youtu.be/YLHVGhSI54U


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## Steely (Sep 24, 2017)

massgrass said:


> I also have a Timemaster 21199 and the Briggs & Stratton pdf docs point to carb model #590944 with overhaul kit #592172 for a model 140000 engine.


@massgrass Thanks for this. In looking at the overhaul kit 592172, I noticed that I do not have the the oval shaped inner carb gasket. I only have the red o-ring and the outer odd-shaped gasket. Could that be my problem? I had my mower in the local shop for warranty work earlier this summer. I honestly don't know if they would have taken the carb off for any reason, but maybe they didn't put that gasket back on?

What is the little thimble looking brass thing in the overhaul kit? I didn't have anything that looked like that.


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## AZChemist (Nov 7, 2018)

There is the smallest of holes on the left or right side of the venturi of the carb on the front side. I missed this hole the first 2 go arounds of my timemaster doing the same. Take the intake manifold off and give it a go. You will need the smallest of wire to clear the Orifice. When this is clogged the engine is very difficult to start when cold.

Additionally, I've found these motors do need the valve clearance checked often and once one side tightens up ever so slightly it will run poorly because the valve can't fully close.


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## massgrass (Aug 17, 2017)

Steely said:


> @massgrass Thanks for this. In looking at the overhaul kit 592172, I noticed that I do not have the the oval shaped inner carb gasket. I only have the red o-ring and the outer odd-shaped gasket. Could that be my problem? I had my mower in the local shop for warranty work earlier this summer. I honestly don't know if they would have taken the carb off for any reason, but maybe they didn't put that gasket back on?
> 
> What is the little thimble looking brass thing in the overhaul kit? I didn't have anything that looked like that.


I'm no small engine expert, but as for the brass thimble, I'd guess that is the valve inlet seat. To be perfectly honest, I've never bothered with that since my carbs were always surprisingly clean when I opened them up. For the most part, the needle being clogged or worn seemed to be my issue.

My Timemaster is still under warranty so I've never messed with it. But in general, cleaning the carb out and occasionally replacing the needle/gaskets fixes things up for me.


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## Steely (Sep 24, 2017)

AZChemist said:


> There is the smallest of holes on the left or right side of the venturi of the carb on the front side. I missed this hole the first 2 go arounds of my timemaster doing the same. Take the intake manifold off and give it a go. You will need the smallest of wire to clear the Orifice. When this is clogged the engine is very difficult to start when cold.
> 
> Additionally, I've found these motors do need the valve clearance checked often and once one side tightens up ever so slightly it will run poorly because the valve can't fully close.


@AZChemist i snapped a couple pics before putting things back together. Can you tell me which hole it is?


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## AZChemist (Nov 7, 2018)

First pic - those 2 little circles to the right have A very Small orifice. Had good luck then I cleared the tarnish out of there.


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## Thick n Dense (May 7, 2019)

Is there a downside to it surging ? or just that it's annoying?

Mine does this as well but it doesn't bug me...


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