Christmas quiz - starting elderly 2 stroke gardening equipment

[m_c]

Any petrol engine that has sat for any length of time, especially a 2 stroke, usually benefits from a carb strip and full clean.
I usually strip them and dunk them in the Ultrasonic cleaner, however an old pot with water and laundry detergent, and boiled for a while also works.
Simply blowing them out doesn't really get rid of the gum/varnish that old 2 stroke oil and petrol usually leaves behind.


As for the exhaust, it could be indicative of a worn barrel/piston/rings or leaking crankcase, and the extra back pressure is enough to stop fresh air/fuel making it in to the crankcase.

 

[gaz1]

the rotorvator is more like a merry tiller type of thing

i have one with a 4 stroke engine on it and it tynes for fun chews up soil like butter through the soil

just one thing with mine if it finds a good stone its coming out of the ground so its kinda hang onto the thing a good amount

 

[daleyd]

I got fed up messing around with my stihl kombi strimmer/hedge trimmer after I left it stand for about 9 months so I got some aspen fuel - once it ran through it now starts much easier, and now tolerates being left for long periods.

While I was trying to get it started I was pondering about the possibility of stripping it down and sticking a battery drill on it to save my poor arm - anyone ever done this, is it even possible??

 

[wristpin]

Possible blocked muffler. So long as it’s a steel muffler ( not alloy) , take it outside and give it a good cooking with a blow torch .
Unfortunately advances diagnostics on small two strokes do require the ability to check cylinder pressure and crankcase vacuum and pressure together with making blanking plates for exhaust and inlet ports to enable the performance of those checks.

 

[Robotstar5]

I got fed up messing around with my stihl kombi strimmer/hedge trimmer after I left it stand for about 9 months so I got some aspen fuel - once it ran through it now starts much easier, and now tolerates being left for long periods.

While I was trying to get it started I was pondering about the possibility of stripping it down and sticking a battery drill on it to save my poor arm - anyone ever done this, is it even possible??

See post #2, Mustie1 on Youtube

 

[daleyd]

See post #2, Mustie1 on Youtube

Wish I would have asked that when I was red faced and swearing at the thing for not starting

 

[frank horton]

there are some strimmers out there with battery/elec start.....
I have an old but sweet Kawasaki strimmer with the same problems.....plus it will get a new carb...£20eBay.....
just cant spin it fast enough to get it going.....athritis.......
anyway bought a new Echo.....
as for battery models they just dont last long enough.......

 

[Nomad]

A belated update on the "it was working fine last year, we've not used it since" strimmer



Rather than have this just sitting in the shed taking up space I pulled the motor apart, I now know the piston & bore are both badly scored.
That, and the loose inlet manifold & snapped / blocked exhaust point towards it being a long time since this ran properly.

With the cylinder off I can see it's stamped 40F-5-1 which is a 43cc model by Mitsibushi
Now I'm looking to see where I can buy a new piston & cylinder kit so if anyone has any advice or recommend suppliers I'd be grateful.

 

[joebog1]

Must agree that piston and the bore will be/is stuffed.
Dont forget the little gauze filter covering the outlet on the muffler. Its affectionately known as a "spark arrestor ".
Clean it, or remove it all together. ( DO watch for fires!!!! They do spit sparks )

I now buy chinese copies of Honda for a few hundred bucks. Single overhead cam no less.
Two pulls, one to prime, then its away. Hasnt run since last year. I DO replace the fuel thats all.
PLUS I run all my two strokes AND four strokes on "Ultimate " 98 octane fuel. I use modern two stroke oil.
Costs a pretty penny, but even 20:1 engines will run happily on 50:1 synthetic. ( we aint on the Isle of Man ).
Honda copy generator, Whipper snipper, ( four stroke overhead cam 43 CC ) Briggs overhead valve ride on, 17 HP.
Sold my chainsaw and pole saw, BOTH two strokes, and although they ran perfectly, they are too heavy for my 70 years.
Chainsaw was 58cc 24" bar, pole saw ( with hedge trimmer fittings, plus whipper snipper BOTH never used )43 CC.

Joe

 

[addjunkie]

Strimmer Parts: Garden, Grass & Petrol Strimmer Spares

simplygardenspares.co.uk

But often, sad as it may seem, cheaper to bin and buy new. Especially if your time has value

 

[mtt.tr]

A belated update on the "it was working fine last year, we've not used it since" strimmer

View attachment 388628

Rather than have this just sitting in the shed taking up space I pulled the motor apart, I now know the piston & bore are both badly scored.
That, and the loose inlet manifold & snapped / blocked exhaust point towards it being a long time since this ran properly.

With the cylinder off I can see it's stamped 40F-5-1 which is a 43cc model by Mitsibushi
Now I'm looking to see where I can buy a new piston & cylinder kit so if anyone has any advice or recommend suppliers I'd be grateful.

Might be a zenoah clone

Is this close?

43CC STRIMMER TRIMMER BRUSH CUTTER 40MM CYLINDER & PISTON KIT

Cylinder & piston kit suitable for various 43cc strimmer / brush cutters.40mm diameter.Please, check your old part with the pictures and measurements prior to purchase.

gardentoolspares.com

Port location on the gasket looks similar

 

[minimutly]

2stroke engines rely on good crankcase pressure/vacuum…..if the crank seals are perished it won’t run….

Yeah, this is true. Also, if you manage to flood the crancase they will start, and foul the plug straight away. I've taen to blowing down mine by holding an airline in the plughole, turning the engine with the throttle open until you get fimes coming back out the carb - need three hands though...

 

[Nomad]

Might be a zenoah clone

Is this close?

43CC STRIMMER TRIMMER BRUSH CUTTER 40MM CYLINDER & PISTON KIT

Cylinder & piston kit suitable for various 43cc strimmer / brush cutters.40mm diameter.Please, check your old part with the pictures and measurements prior to purchase.

gardentoolspares.com

Port location on the gasket looks similar

That looks like a winner ! The inlet port is a good match. The only difference I can see is yours has a rectangular "frame" around the port but I think that's just cosmetic or for a different style of mounting.

For reference I found a site with a great exploded parts list for E40-5 engines, the cylinder head here looks the same pattern as mine and has no rectangular frame around the port http://www.usuredo.com/1E40F-5-Gasoline-Power-Engine-pd40306027.html



Do crank seals normally go when the bores go? I'd prefer not to split the crankcases if they don't need it, also prefer not to put a new top end on it and find I then need new seals

I'll need to pull my motor apart and measure things before ordering anything but it looks good so far

Thanks for the help everyone !

 

[mtt.tr]

I use one of these,

Multifunctional Hand Held Vacuum and Pressure Pump Tester Kit Brake Bleeder Comp | eBay

Find many great new & used options and get the best deals for Multifunctional Hand Held Vacuum and Pressure Pump Tester Kit Brake Bleeder Comp at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

Cut a piece of rubber to and clamp it between the carb and exhaust, then pressurise the crank and check for leaks
Then draw a vacuum this will prove or disprove the crank seals.

For the money it's a good pump had mine a number of years, good for checking sensors. I used it the other day to prime a load of night heaters.

 

[Alan Reynolds]

Thanks to everyone who made suggestions, it's appreciated (especially the ones with links or ways to test the faults)

Update on the "it was working great last time we used it last year" Strimmer

It's alive and twitching (hopefully the next stage will be to get it alive & kicking)
Compression seems good, better than last week so letting it rest for a week has loosened the rings?
Loose inlet manifold has been tightened up.
Worn insulation on the sparkplug lead was shorting onto the head (temp repair now done).
Exhaust was loose. It should be held by 2x 8mm bolts - and it clamps a heatproof shield to the head when in place. 1 bolt was snapped, 1 bolt was loose and part-stripped allowing the heatproof shield to slip down making a very effective blanking plate over the exhaust port
Looking through the exhaust port, the piston has several scores on it. Not ideal but I hope it's still ok to run.
It's obviously been apart since it last ran (carb inlet, exhaust, badly routed HT lead, bolts missing from the plastic motor shroud) but I don't know why. I guess because they couldn't get it started.

Latest :
With the exhaust off it fires every time, runs smooth but very flat, not at all crisp.
It won't start if the exhaust is fitted.
If I start it without the exhaust and fit the exhaust while it's running, it dies.
The exhaust has a small blanking plate welded on it, it's been done deliberately and looks DIY but I have no idea why? Repairing a hole, original but poorly finished??
I'm thinking the exhaust is partially blocked inside, I tried blowing through it and it seems to flow freely but I can't think why else the engine dies when the exhaust is fitted
Will remove the blanking plate and see if that helps.

Summary. Be skeptical of anyone selling tools you can't test if they say "You can't see it running but it works great, honest"

Chap in the workshop had a little kart engine that refused to start. It had fuel and spark and the compression was good. I told him to take the exhaust off and it started immediately. There was a great deal of fuel mist blown out of the exhaust port as fuel had accumulated in the crankcase due to an earlier fault with a duff coil. Once it was cleared out, it was fine with the exhaust fitted back on.

 

[mtt.tr]

Chap in the workshop had a little kart engine that refused to start. It had fuel and spark and the compression was good. I told him to take the exhaust off and it started immediately. There was a great deal of fuel mist blown out of the exhaust port as fuel had accumulated in the crankcase due to an earlier fault with a duff coil. Once it was cleared out, it was fine with the exhaust fitted back on.

Ms200 are bad for this, if they don't start ignition off 10 very slow cranks which clears the excess fuel

First pull they start.

 

[Nomad]

Strimmer update - the new pattern barrel & piston were soon fitted and it seems to be working the way it should

The fix cost about £40 in parts delivered (including crank seals & crankcase gaskets - not needed so are here as spares)

Stuff you have fixed today

My oven. A 25 year old Neff double oven. It went pop and blew a fuse yesterday night. Two of the tracks on the pcb had evaporated. A bit a very thin wire and some ugly soldering later and it works. Which is good as we have visitors arriving in a few days.

www.mig-welding.co.uk

No work done on the chainsaw or merry tiller but both would be handy to do some jobs I have coming up