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4 Stroke Strimmer


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07-07-13, 08:16 AM   #1  
4 Stroke Strimmer

Sorry if covered before but I am at my wits end and joined this excellent forum hoping for some help.

I live in France and the after sales service here is non existant.

Three days ago I purchased a 4 Stroke Strimmer with a Briggs & Stratton engine. I took it home, assembled it, filled with oil and petrol and the thing would not start. After a couple of hours pulling my hair out I took it back to where I had purchased it who, after checking it, told me I had overfilled it with oil and now ruined the engine.

After complaining about their bad service they reluctantly emptied the oil, cleaned the air filter, refilled with oil correctly and managed to get it going. The guy then told me to keep my fingers crossed and sent me on my way after insisting I signed a bit of paper saying I prepared the Strimmer and not them.

I ran it OK for about 1/2 hour at home but now it does not work.

If I pump through some petrol it will start for a few seconds but very quickly gives up the ghost. It looks as though it is not sucking up petrol from the tank, but that might just be me.

Can anyone please help or have I just wasted nearly 300?

Thanks.

P.S. You possibly won't know the make of the Stimmer but it is a Bestgreen.

 
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07-07-13, 09:19 AM   #2  
Usually you won't ruin an engine by overfilling with oil, but you can cause excessive crankcase pressure and push oil past rings and crank seals. Just a little bit over doesn't ruin anything.

If you got oil on the filter you probably got oil in a few other places you don't want it and oil in the fuel system can clog it up temporarily, until it gets cleaned out.

I would change the fuel in it, take off the air filter, and get it started. Then run it for a short time without the filter (not while trimming, but just in a clean environment. Run the engine at idle, then back up to half then full throttle a number of times to help clean it out. If it still smokes after that, replace the fuel again. Then clean the filter again and put it back on and use the trimmer.

The longer you use it, the better it will run.

 
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07-07-13, 11:39 AM   #3  
Thanks for the advise. I will go try that and report back.

 
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07-07-13, 12:02 PM   #4  
Hi.

Back again.

I did what you suggested and it started running OK on tickover so I am nearly there.

However, when I put the air filter back on or run it a bit faster it stopped again.

By the way it is not smoking. Also there are air bubbles in the fuel line. Could this be anything to do with it?

 
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07-07-13, 01:29 PM   #5  
It's not getting enough fuel.

What all did you have to assemble on the engine? Did you put together the gas tank/carburetor mount/fuel lines?

 
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07-07-13, 11:42 PM   #6  
Hi.

The stimmer was completely assembled. All I had to do was fix the handle on it and put in oil and fuel. I was told the problem was I overfilled it with oil which I must admit it looks as though I did.

I am not mechanical and I did mention to the place I bought it from that, if oil levels were so critical, perhaps they should have prepared the striimmer for me and advised accordingly.

I have had many strimmers over the years but this is the first 4 stroke that I have purchased.

You live and learn!

 
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07-08-13, 10:06 AM   #7  
Bit more info.

If I pump through loads of fuel (10 pushes of the plunger thingy) it starts, runs for a few minutes then stops. It must be something to do with fuel not being pumped through I think.

 
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07-08-13, 07:23 PM   #8  
In an all position carb, there is a diaphragm that pumps the fuel. Those are usually driven off a pulse from the crankcase that cause the diaphragm to respond to the differences in pressure. It makes it move up and down which pumps the fuel into the reservoir for the carb to feed off of.

If all the lines were hooked up correctly, the overfill of the oil in the crankcase could have caused a problem with the pumping diaphragm.

I believe you'll have to have the carb dismantled to check the pump. The primer you get some run time out of works independently of the carb diaphragm. It's kind of like its own little pump.

 
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07-09-13, 12:45 AM   #9  
Hi

Thanks for that info. Perhaps it would be worth while having a service done on it then?

 
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07-09-13, 06:58 PM   #10  
The average person can go through a carb if they're careful and have at least some mechanical aptitude. But if you have a shop or local do-it-all guy that does that kind of work they shouldn't charge too much to do the work on a small carb. I think that's the route I would go.

 
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07-10-13, 04:02 AM   #11  
Thanks Guys.

One last point on this. The Strimmer was filled with a 4 stroke carburant that the store sold me. On the recommendation of a friend I flushed it out and filled it with petrol - it then ran for about 1/2 hour ticking over. Under load it lasted about 15 minutes.

I think we are nearly there.

I notice now however that there are air bubbles in the fuel line. How does this happen and could this be the problem?

 
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07-11-13, 06:14 AM   #12  
If you have a completely closed fuel system you shouldn't have the air bubbles. Since the hydraulics on that fuel system are draw only, which is all the way into the engine, any opening for air would get into the system. This would start at the filter, all the way into the carburetor.

But lets say the diaphragm for the fuel pump is damaged and there is air infiltration there you could have air entering the system and backing up into the fuel lines. Or you could have a filter in the tank coming up out of the fuel and allowing air to enter.

What was the carburant you're referring to - a type of cleaner for the carburetor? That could have been to clean up the oil residue from the overfill. That wouldn't be the problem.

I believe the reason you're getting better results is the oil is getting cleaned up and the longer you run the engine, the better everything will work. Taking a look at the carb should still be a consideration.

 
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07-11-13, 06:48 AM   #13  
Hi marbobj

Many thanks for trying to help.

You are getting a bit technical for me now as I have no idea what a 'closed fuel system' is. I am just a normal guy buying a strimmer wanting it to work.

The 'carburant' or fuel they sold me was in place of petrol. It supposedly had additives in it. Anyway I have ditched it now and filled it with petrol. I have a friend who will hopefully look at the carburettor for me in a couple of days. If this does not work it's in the bin!

I need a strimmer for a couple of jobs that I do and I purchased this one in all faith. The supplier has let me down big time. I tried to save a few pounds not buying a Stihl but will now learn the hard way and go buy the one that I should have done in the first place - that's if my friend fails.

Thanks everyone.

 
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07-11-13, 07:59 AM   #14  
All fuel systems are closed systems and aren't made to have air in them. They are essentially a hydraulic which moves liquid. If you find air in them you have to look for the reasons.

Stihl is a very good brand of trimmer, but a Briggs and Stratton engine has very good credentials.

I really don't think you've wasted money with what you bought. You just have a common problem that needs attention.

Good luck.

 
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07-28-13, 11:17 PM   #15  
Quick update on this.

I took the Strimmer back to their Service Department willing to pay for a service. After two weeks without hearing anything I went back to ask about the Strimmer - they told me to come back in another week.

Furious I demanded the Strimmer back and now have it at home still not working.

I managed to get it going once and it ticked over for over 20 mins quite happily but as soon as you started to use it it died.

Needless to say I will never use this Company again. After Sales service in France stinks and I am now way over 300 out of pocket and no doubt more when I have to go buy another Strimmer.

 
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07-29-13, 03:58 AM   #16  
Sorry to hear that. The service department should have been able to fix that carb inside an hour.

I really think the problem is with the diaphragm in the pump part of the carburetor. There is an outside chance it could have been damaged with the overfill of oil, but that would be unusual.

Those carb kits for a professional would be pretty simple to install.

I believe I would contact the company that makes it and see if they can help you.

 
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