Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

How do you diagnose a 2-stroke to find out if someone ran straight gas through the engine and wrecked it?

I found a Toro snow commander snow thrower (see photo). I've never used a toro single stage so I thought I would snatch it up. The previous owner said that it did not run. Apparently it ran last year but not very well. Looks like it sat out in the rain most of its life. That's all I have to go on. 

At 24" the blower is wide for a single stage and very heavy (over 100 lbs).  The 7hp engine appears to be the same InTek 2-stroke as the Toro 3650 and 2450.  I noticed that it does have an electric start feature.

Now that the blower is sitting in the garage, I realize how large it is. Think "single stage monster."  A very odd beast,  a mass of red plastic.  Toro only sold these (model 38602) blowers for a few years (2001, 2002, 2003, ?) with a list price of $960 US. There was a Toro recall in 2006 for 2001 and 2002 models. This one is a 2003 model.  I don't think they were very big sellers (expensive, hard to handle, too many parts).

I don't have any experience with 2-strokes so this is a new adventure for me. Is there an easy way to determine if someone ran the engine with regular unmixed gas and ruined the engine? Would I notice anything when pulling the starter cord?  I thought I try to rule that out first if there was an easy way to do so. 

It's been a year now, how's it running?  I recently got a very similar unit (CCR 2450 - 38413) with the R Tek 5hp for free but the thing won't stay running.  After the first time you start it, it will run under a load for several minutes and then die (can't do anything to save it like primer or choke).  On subsequent startups it will die very quickly.

This is why I got it for free.  The guy I bought it from said it worked perfectly but was leaking gas before he brought it in for service at Acme tool.  Acme found the recall with the cracked gas tank and replaced.  When my friend received it, it wouldn't run.  Then Acme rebuilt the carb and it still wouldn't work.  The tech at Acme said that it was due to low compression ~100 psi and it should be 130.  Now it's in my lap.

I've pulled the carb apart and looked for anything outside of the ordinary, cleaned it and put it back together.  I noticed remains of a sticker around the pilot-jet but finished cleaning the carb and replaced.  It ran exactly the same, no joy.

Recaling the tape remains around the pilot jet, I put a piece of tape over the pilot jet..  It worked perfectly, for about 10-15min (much longer this time) and then died again.  Now it's possible the tape came off??  What did you do with yours?  Did you have to tape over that pilot jet?  In this discussion forum thread I've seen someone suggest that you don't have to cover the pilot jet but I've also seen in the R tek service manual that it's one of the differences between the R Tek engine and the DuraForce engine.  What did you do?

Pull the head off and see if the piston is dished out on top or burnt. Also can run the piston down and check some of the cylinder for real deep scratches. Or take the exhaust off and take a look see in the port that the rings arent scraped over

I have to think that if it ran perfectly before my friend brought it in for service on a gas tank issue, it should run perfectly after a gas tank service.  Would there really be a need to pull the head off at this point?  I'm hoping for a an easier solution...

It's difficult to get an accurate compression reading on these machines if they have a compression release mechanism.   Chances are the compression is fine.  Your problem is likely all fuel or carburetor related.  If you have the basic skills required to clean it, I suggest you pull it off yourself and go over it.  It may need to be thoroughly cleaned.  Just because someone said they cleaned it doesn't mean it was done right.

Another thing to look for, is to make sure the fuel cap vent isn't blocked.  if you get the machine running and it starts to falter, loosen the fuel cap to see if you can get air into the tank. 

If you clean the carb and it still doesn't work, look for a new (preferably metal) carb to replace it.  Ebay might have one for around $20.00 or so.  Either way, it's a great machine that's worth a bit of expense to get running right. 

Will the engine turn over?  If some one ran  gas through it , it would throw a rod or weld it self together. If it is locked up , i would not bother with it. It may be welded or rusted up.From your pics your carb is messed up and i'm sure your ignition is too . Just buy another engine. You will make out cheaper.

Wow - I appreciate all of the suggestions! I'm with you (Borat) on the compression thing, I can't see that being an issue when it runs perfectly under load but then when it seems to really warmup, that's when it dies. Weak compression would not manifest itself like that (I don't think). As I mentioned earlier, I did take the carb apart, removed the jets/nozzles and sprayed it down good through every orifice. I think on this model that the pilot jet needs to be covered. I did put a piece of tape over it and got it to run much longer. I talked to the coworker today that gave me the machine and he gave me another clue - He said that when he originally brought it in that the repair person at Acme told him that the fuel filter was installed the wrong way and he switched it around. Note, it worked fine for almost 10 years the way it was. I did try removing the fuel cap to check for vapor lock, that made no difference. This leads me to believe I might have a couple of things to look out for. 1) Instead of putting in a new one, he just changed the orientation of the filter which would allow any accumulation from the last 10 years to go into the carb! The good news is that the little plastic carb has a screen on the main jet and it doesn't appear to have any issues with the needle/seat like I'd expect. This is good. But is there anything special about the fuel filter on these things? Does it have a check valve. I blew through it last night and there didn't appear to be any restriction but I blew from the carburator into the fuel tank, not the other way around. That would explain the quitting after a few minutes and then not staying running if it was starved for fuel and burned what was in the bowl along with the line after the fuel filter and then wouldn't stay running untill it sat a while until gravity filled the float bowl again. I could test this just by blowing into the gas tank after it quits and see if it extends the run-time to let me know if I'm on the right track (a trick I learned on snowmobiles to get the fuel into the bowls after you've drained them!). 2) I'm still thinking about the 'plug' to the pilot jet on the side of the carburetor. I was reading in a service manual for the R-Tek and it's sibling the 'DuraForce', one of the differences it specifically stated was that the pilot jet had a plug. By plug I'm sure they are referring to the decal that originally was placed over the top of the pilot jet. Last night when I tried plugging the pilot jet it worked perfectly for about 10-15min (much longer than before). So it's possible that the piece of duct-tape that I slapped on there came loose. When I open it up tonight to put in a new fuel filter, I'll clean the side of the carb with alcohol and put a good piece of tape over the pilot jet to see if that changes anything. I know, I should only change one thing at a time but taking that shroud off is a royal pain and running it under load without the shroud means leaving the carburetor's intake exposed to the elements - I personally don't get how that engine doesn't fry when it's no doubt sucking in ice crystals. This is the big thing that all the warnings on snowmobiles scare you about and use multiple foam filters that mice love to eat. Finally, if you know of a metal carb for this that will work, I'm open to suggestions. Plastic carbs don't exactly inspire confidence. I'm willing to throw some bucks at this thing, it works great on this spring snow where it cleans all the way down to the concrete vs. just leaving a thin layer like my bigger snowblower does. It will also work great on my ice rink where it's imperative to clean all the way down the ice before resurfacing. This thing could save me a bunch of time!