Troy-Built 4.5hp running problem

[Kestas]

I've had this power washer for a number of years with no problems. Now all of a sudden it won't stay running. It'll start when I prime it, but it only runs for a couple seconds before it dies. I've taken the carburetor completely apart, cleaned it, inspected it at 20X magnification, and find that it is whistle clean. I use only pure gas to avoid the phase separation. Where should I look for the problem?

 

[bubbatime]

Your carburetor is plugged up still. This is why I always advocate to replace the carburetor on these engines and dont even bother cleaning them. A person can spend hours and hours rebuilding a carb ($10-$20 for a rebuild kit) and it still wont run right after cleaning. Or just buy a new carburetor ($10-$25 on average), slap it on in 3 minutes, and engine runs like new again. Much easier and less hassle just to spend the money up front and replace the carb. Check eBay and Amazon for best prices on carburetors.

If it is one of those carbs that is mounted on top of a metal gas tank with a diaphragm under it, the rubber diaphragms dry up and need replaced.

 

[Hokiefyd]

I agree -- I never spend time rebuilding these small carburetors. Hopefully, they're not expensive for your application. A Troy-Bilt pressure washer is likely using a Chonda or Briggs. A Kohler is generally a Chonda. If you list the exact engine, we can probably help you source a new carburetor.

 

[ironman_gq]

There's tiny little passages in those carbs that are nearly impossible to clean. Only thing I've found that works reliably is an ultrasonic cleaner and about an hour of cycle time.

 

[horse123]

IMO carbs are the worst invention in history. They practically break down if you [censored] in their direction at the wrong time.

Fuel injection might cost a lot more, but 99% of the time it seems to be infinitely more reliable.

 

[Highboy]

I just changed mine on a Home lite PW. Got a new carb from Amazon for about $20. Started on first pull.

 

[old1]

Like others have said unless you know where every TINY passage is in a carb, and know why it is there, and where it goes, it is better to just replace, or have a pro do it. Personally in 45 years of working on small engine and auto carbs, I have found only a few I couldn't fix.

 

[edwardh1]

how are the honda engines so much better?

 

[Hokiefyd]

Originally Posted By: edwardh1
how are the honda engines so much better?


I don't think anyone in this thread said they were -- we don't even know the brand of the engine in question, here, do we? Any of these small engines are subject to carburetor issues. I've replaced Briggs carburetors, Tecumseh carburetors, and Honda carburetors. I'm not sure any one brand is less prone to those types of issues than any other.

 

[Kestas]

Mine is a Briggs & Stratton; family 5BSXS.1581VG. It's the type where part of the carburetor bottom is a die cast part of the fuel tank.

I have it apart. Nothing looks broken or ripped. I am not replacing it just for being dirty. I gave it a more thorough inspection. Found some debris that may have been in the passages. It's now getting a good cleaning in the ultrasonic bath.

 

[old1]

Not familiar with that model number. Tried to find that model # and couldn't. Is it a horizontal (side) shaft or vertical shaft engine? Is it a plastic or metal carb? Also, you need to replace the diaphragm no mater how perfect it looks. Unless you just replaced it yesterday of course.

 

[Kestas]

This is a vertical shaft application. The carb is plastic, and it looks like the one in this link.

Yes, the diaphragm looks good, with the exception that it is stretched under the spring. It's a cheap part, I'll go ahead and replace it.

 

[old1]

Ok, now that I know what you have, I will give my 2 cents worth. A good cleaning and a new diaphragm SHOULD make it work like new again. make sure the screen on the long suction tube is clean, and the one over the other jet tube also, and be sure the jet is open all the way to the carb throat. Carefully put it together being sure to not get a fold in the diaphragm, and tighten all the screws with a staggered motion. Then put gas in the tank and see if the primer pumps a good stream of gas. If it still doesn't work, those carbs are cheap.

 

[yeehaw1960]

Sorry for being long winded. I don't even try to type something different. I just cut and paste for the tank-mounted Briggs question. Remember to laugh at me for adding the digital picture sentence in there...right up until you're staring at it (or anything else) trying to remember how it goes back together. I wish we had digital cameras the first time I did a (drum) brake job!

Take the air filter off with a flat head screw driver. Take a digital picture of what is underneath for later reference. Remove the 1/2 inch bolt that holds the carb/tank to the engine. Remove the 3/8 (or 7/16) inch bolt from the end of the tank. Pull the tank away from the engine and do what you have to do to remove the linkage from the carb. If it’s a long linkage rod with one spring, remove the spring and set it aside before removing rod. If the spring is attached to a short linkage rod, just pull the linkage of out the hole it’s in.

Remove the 5 Phillips screws holding the carb to the tank. Inspect the gasket/diaphragm and ensure it is soft and pliable. Completely blow/empty out inside and top of the tank. Push primer bulb in to expel excess gas from carb. Blow air on the bottom of the carb and into the hole at the base of the pickup tube. (Not too hard into that hole or the primer will burst). Air and remaining icky gas should come out of pickup tube. Place your thumb over the spring so it won’t blow away. Reassemble carb and reinstall. Slip the screen off the bottom of the carb and poke through (clear) the hole that is under it. Should be good to go. Don’t take the gasket and diaphragm apart, but if you do, make sure you assemble in the following order. Tank, diaphragm, gasket, then carb. Chances are, the diaphragm is bad. It usually is. O’Reillys in my area sells them for about 3 bucks, and the mower shops charge 7 or 8. I think Briggs is STILL putting on the diaphragm kits with the bad gasket that isn't wide enough at one point to keep the diaphragm from slipping off and creating a vacuum leak. The perils of having 10 million gasket/diaphragm sets manufactured, then not wanting to throw them out just because they only work for 6 months. 99 percent of new, aftermarket sets are good though. Have fun!

 

[Kestas]

FIXED! A good ultrasonic cleaning of the carburetor and fuel tank did the trick. The fuel tank was then set outside in the blazing sun to dry out the water. It now runs like a champ.

It's amazing how little debris the carburetor tolerates.