# Powermore OHV 208cc surging



## griz4718

My neighbor has an MTD snowblower with the Powermore OHV 208cc engine. It starts then begins "hunting" until you load it with snow. Then it smooths out The carb does not have the fixed jet in the bowl bolt. Anyone have any suggestions???


----------



## Shryp

Maybe have a peek at post 13 over here.

http://www.snowblowerforum.com/forum/ariens/877-repainted-my-blower-2.html


----------



## frog

I had a powermore 179cc in a troy bilt and I drilled out the main jet to .030, and the fixed idle jet to .017. ran perfect and turned into a one pull starter. last year I sold that one and bought a sno tek with a 208cc LCT. I drilled the jets on it too.(different sizes as the carb had bigger jets already) and have had the same improvement. The newer engines are jetted way to lean at idle and midrange.


----------



## Oldphil

No load surge many times is caused by improper idle adjustment, usually set too high!


----------



## GustoGuy

That is true, My 212cc Predator surged a bit at 25 degrees wit the stock jetting. For every 40 degree or so drop in temperature you need to go up about 1 jet size since the air is denser when its cold out. I enlarged the main jet with super-floss and polishing compound and carburetor cleaner. It took me about 3 tries and I have it running perfect. I used it at 2 degrees about week ago and it ran perfect and I did not have to use any choke on it.


----------



## Apbling

Hi all

I have the exact snowblower and exact problem as the original poster. I am quite handy w carbs, but on motorcycles. The snowblower ran fine last year and wasn't stored properly over summer. Now I have to keep the choke on a bit to keep it from hunting. I am guessing a bit of crude is blocking a jet. I downloaded the service manual for this motor. Looks to be a pain to get the carb off and I'm also a little confused about the pilot circuit. The manual says to pull the little plastic jet out and there is a brass orifice in it. Is this my pilot jet? The pics and explanations aren't the best in my opinion. Also not looking forward to messing w the throttle and choke linkages. Any hot tips for me before I dive in?


----------



## HJames

Take pictures of all carb linkages before removal for reference when you reinstall, nothing worse than rebuilding a carb and forgetting where the linkages go.


----------



## Apbling

I'll definitely be taking photos before I disassemble.

The manual speaks at length about the main jet, which is fine and dandy, but then it talks about a metering plug. It then just makes a backhanded comment about the transition holes being drilled into the carb body and that they are behind a brass welch plug next to the air screw... I see the plug and the screw, but the manual doesn't tell me anything about them. Normally I'd screw the screw in, counting the turns so I know where it needs to go back for stock setting. Then I'd pop the welch plug out and make sure the transition holes are clean, but I do not know for sure if there is anything below the welch plug, or is the welch plug essential for operation or is it just to deter the average person from tampering with the carb settings...


----------



## HJames

With this being a non- adjustable carb, the only adjustments that you can make are going be of a permanent nature. If it ran fine without choke last year I would say it just needs to be cleaned, so no "adjustments" would be necessary. Remove the idle circuit(pilot circuit) and run a bread tie wire through it and spray with carb cleaner until it is clean & clear, do the same for the high speed circuit/jet & emulsion tube.Do not remove the welch plug unless you have a new one to replace it, as the carb cannot be run without the welch plug in place. Your carb could be made by a number of Chinese companies, once you know which company made the carb you can search for the rebuild kit for it if needed. Don't let anyone tell you that a kit doesn't exist for Chinese carbs, they do and I've used them.


----------



## Shryp

You don't have to remove the carb to get to the jets. Before unhooking anything I would try to simply remove the 1 nut in the center of the bowl and start there. Clean the bowl out and then take a good flat head and remove the main jet from the hole that the bowl nut screwed into. The pilot jet is under the low speed rpm screw. Remove that screw and then pry it up. Most times you don't have to actually remove the carb from the engine and deal with the linkages and gaskets.

There is also a smaller bowl before the main one that is suppose to catch contaminants before they reach the carb. Might want to clean that too.

Disassembly, Cleaning and Repair of Carb 16100-ZF6-W10 on Honda GX390 QA2X Engine

If you need some help look on youtube for videos of Honda carb rebuilds.


----------



## Apbling

Thanks HJames and Shryp. It's a huayi carb. yippee, looks chinese. I was curious what exactly was behind the welch plug. On my motorcycles the plug just hides the pilot screw so it can't be adjusted, but the manual eluded to there being just holes behind it. Glad I didn't go gung ho and pull the plug out. I will try and do this without removing the carb, but in my past experience I've spent more time trying to balance the float needle just so it get it all together, but once again, that was on an old Kawasaki bike.

One thing that is still confusing me and I can't see what I exactly have because I haven't removed the shrouds yet is the pilot screw. I will attached a cropped photo from the MTD shop manual. In one photo you can see the pilot screw with the knerled head and spring, the other looks like a fixed one, in consecutive photos nontheless. I guess my plan of attack will be clean the main jet, pull this goofy rubber pilot jet, maybe the screw it if looks like it's meant to be removed, clean all that and give it a go. I have handled much worse (a 1972 honda CL360 that sat for 23 years), but the documentation I had was much more helpful.

An odd thing... in motorcycles if you need choke all the time, its almost ALWAYS the pilots...mainly because they are so small and clog easily. Odd thing is my snowblower surges at all throttle positions without the choke. I would think at WOT that the pilot circuit doesn't really account for THAT much fuel compared to the main. Oh well...

BTW, I apologize for the old thread revival/thread jacking. I have been trying to find good youtube/website info, but everyone seems to neglect the pilot circuit in cleaning. They all cover the main jet, but not the pilot. Also just noticed as I was making sure the photo loaded, the photo is not a Huayi carb...


----------



## Apbling

Well, it's fixed. Taking the shrouding off was worse than the carb. There was little crumbs of dirt in the carb, but no major smoking gun. Good cleaning, back together, runs good as new now. Thanks everyone for the help. 

Btw the air needle I spoke about - it looked permanent and not meant to be adjusted so I left it alone.


----------



## premosound

*Service Manual*

Hi, I'm new here. Ran across this forum while searching for the Service Manual for this engine & noticed that Apbling was able to download it. Sure would appreciate that site location. Thanks.


----------

