Outdoor Power Equipment and Small Engines - Troybuilt Trimmer

A customer brought me this trimmer to repair,it would only sputter,try to start then die.The model # is TB425CS 4 cycle,I change the fuel lines,and the fuel filter as it had dirt in the gas tank,also rebuilt the carb. adjusted the valves,check the spark arrester in the muffler,still does the same thing start then dies,there no adjustment screws on the carb. only the idle screw,the only thing I could not check good was the compression,because the fitting would not screw in the spark plug hole the plug hole was smaller than my gauge,I put my finger over the spark plug hole it(seem) to have good compression,I don't know what else to check,could it have a blown head gasket,also who makes this type of engine in this trimmer.Sorry for such a long forum.

Thanks
Jerry

Try this web page ... http://www.troybilt.com/webapp/wcs/stores/servlet/product_10001_14102_10138_18652_-1

It's rather unlikely that you have a blown head gasket but, of course, with anything mechanical, anything that can fail likely will fail in time. So, don't overlook the possibility but I wouldn't concern yourself with this just yet. You stated you rebuilt the carburetor, how exactly did you do such and with what type of rebuild kit and with what type of cleaner solution? This is an old Ryobi trimmer in Troy clothing, by the way, which is an MTD product.

I used carb spray and the little tube on the end of the can and sprayed all the little holes to make sure they were clear and blew it out with compressed air,I replaced all gaskets,took the inlet screen out and put it on a paper towel used a dropper and some water to see if water would go through and it did.This carb. wyl 196 the spark plug is about half the size of a regulator plug hole did not have a adapter to fit by compression gauge.There no adjustment screws on this carb only the idle screw.

Thanks
Jerry

Did you replace the fuel pump and diaphram parts of the carb or just clean? Sounds like you are not pumping fuel into the carb. The plug is a special plug and I am not where I can give you the Champion number for a new one. If you spray some carb cleaner into the choke opening, does it run? or try to?

Yes all the gaskets and diaphrams are new,the starting instructions says not to squeeze the trigger,just press the primer 10 times and then pull the rope,it does try to start but then dies.I took the carb. back off and took it a part again to make sure that all diaphrams and gaskets are in the right order,still does the same thing. Still at a lost.

Jerry

Update,got it running,really don't know what I did only thing I did before I tried to start it took the plug back out,check for spark again,like before,put plug back in and it started right up.Thanks guys for all the help great forum,thanks Doubleh47 for the web page downloaded the owner manual.

Jerry

It's always nice to know what was required to get it running but, I suppose, as long as it's running, that's what matters most. Keep your finger crossed!

Puey61 the only other thing that I did was put a teaspoon of marval mystery oil in the spark plug hole,and let it set over night,then took the plug out and check for spark,then it fired right up.

Jerry

Mysterious, isn't it?

On occasion the rings will loose their seal, especially if the engine gets flooded. I have seen it in 2 cycle snowthrowers when the owner tries to start with summer fuel or last years fuel. I also had a shipment of new chainsaws that were shipped accross the great pond from the old country that would not start. All I ended up doing was to put about 4-5 drops of oil in the cylinder and pull it over a couple of times before reinstalling the plug and they would start right up.

CAMINO KID I guess that's what happen still starts and runs great,I have worked on a lot of 2 cycle trimmers,this was my first 4 cycle,I will keep your reply in mind,thanks again.

Jerry