JoihnDeere LT166 Carb Problem

[StarTech]

The Tiger is Briggs is getting to where they don't stamp the jet size on the jets. I tried for several years to get other techs to send the pns and stamped sizes to me so I could make up a cross reference chart. Currently I only have a few Nikki listed as they are the ones I have used here.

I just recently ran across a seller claiming two different Briggs jet part numbers were the same one when I definitely know a 111 and a 118 are not the same jet.

 

[MadMopar]

Bypass the anti afterfire solenoid on carburetor so you don’t have to spend $150 on part. Do not throw that OEM (probably Walbro) carburetor away. Measure bore where jet goes in and threads. Look around for smaller jets and buy a couple. Go smaller than you think and you can drill them out with micro drill bits until air/fuel mixture is correctly reached.

Man, I didn't even think about that. I still have the original carb and I'm pretty sure it does have the HA jet in it. It should still be fine. Last time it was used it had run out of gas (solenoid) so it should be OK. I have used starter fluid to run it so I'm sure all the gas was sucked out of it.

How important is that solenoid anyway. Do these machines have that much of a problem with afterfire?

Just have to find a bolt that fits. Don't want to damage threads in case I do need that solenoid.

I have the parts manual for the engine and it actually shows and gives a part number for a plug (just looked). Apparently it is bypassable according to B&S since they make the plugs.

 

[StarTech]

Walbro are usually 5/16-24 and Nikki are M8-1.00. Only about 5mm in length.

 

[MadMopar]

Walbro are usually 5/16-24 and Nikki are M8-1.00. Only about 5mm in length.

Accordingly, it's a Nikki. Went to Ace with the carb and the solenoid and got an M8-1 and a couple of 5/16 brass washer (bolt was a little longer then the solenoid). Spent $2.31.

Just cranked it and as soon as the bowl got filled up started right up and is running like a champ. No more black smoke and is nice and smooth. Perseverance has paid off.

Now to put it all back together and go for a long overdue ride.

The Tiger is Briggs is getting to where they don't stamp the jet size on the jets. I tried for several years to get other techs to send the pns and stamped sizes to me so I could make up a cross reference chart. Currently I only have a few Nikki listed as they are the ones I have used here.

I just recently ran across a seller claiming two different Briggs jet part numbers were the same one when I definitely know a 111 and a 118 are not the same jet.

The jet looked like it was stamped maybe (0) and an 8. The (0) is off the edge and looks almost double stamped. The other # is definitely an 8. Could be 118 but wasn't clear. I'm 99.9 % sure this the HA Jet since it is running so well and I'm around 5500'. The ref # in the Engine breakdown is 72A and the part # is 694069 for the high altitude jet. I'm sure that is what was in the carb. Hope this helps you somewhere and helps anyone else looking for it. This info is from the B&S Vanguard parts breakdown manual.

Thanks to all who have taken the time to try and help me and a special thanks to Tiger Small Engine and StarTech for the answers I needed.

 

[MadMopar]

After running for a bit, started running rough and slight smoking. Remember the adjustment on the top of the carb and smoothed out with adjustment. Even had to lower the idle adjustment, running too fast at low idle.

Took it for the long awaited ride and ran good. Back in business.

 

[bertsmobile1]

Jets should be reamed rather than drilled and by preference using a pin drill
Any distortions to the surface of the hole will make a drastic difference to the flow rate
jet reamers are very very expensive
Micro drills , particularly those cheap sets from China are rubbish and will be all over the place diameter wise
I stuck some under the macroscope and found that all bar 1 were sharpened of centre so all will cut a bigger diameter thole than the advertised size
Apart from that the increments are way too big for stepping
The other thing you are missing is that untill you turn the blades on the mower is running off the idle jet, not the main jet so stufing around with the main jet will do nothing to make the engine stop blowing smoke standing still
This is why the manuals go to the effort of calling 3600 rpm "HIGH IDLE" and not running speed .

 

[MadMopar]

Jets should be reamed rather than drilled and by preference using a pin drill
Any distortions to the surface of the hole will make a drastic difference to the flow rate
jet reamers are very very expensive
Micro drills , particularly those cheap sets from China are rubbish and will be all over the place diameter wise
I stuck some under the macroscope and found that all bar 1 were sharpened of centre so all will cut a bigger diameter thole than the advertised size
Apart from that the increments are way too big for stepping
The other thing you are missing is that untill you turn the blades on the mower is running off the idle jet, not the main jet so stufing around with the main jet will do nothing to make the engine stop blowing smoke standing still
This is why the manuals go to the effort of calling 3600 rpm "HIGH IDLE" and not running speed .

I wouldn't mess with reaming jets. They aren't that expensive to get the correct one. My old carb has the correct one and there is no smoke now with idle up to flat out.

I'm going to assume that you missed the part about my removing the deck and only use it for hauling a rake and trailer around. We have a Craftsman 52" we use for mowing. I just 'punch it' for speed.

 

[slomo]

I doubt that carb has an HA main jet. Unless the mower came from some really good dealer (long shot) at 5500 feet. And they knew about this rich condition. Maybe it does??

Guessing it will still run rich and be down on power compared to a sea level mower. Lower the float level like I mentioned. It costs NOTHING.