One for the small engine experts (GX35 burning oil)

[farmerjo]

Any reason you can't use a heavier grade of synthetic oil in it to keep it cooler and use less oil as it is.

Just asking.

[NonthaburiBear]

8 minutes ago, farmerjo said:

Any reason you can't use a heavier grade of synthetic oil in it to keep it cooler and use less oil as it is.

Just asking.

less oil mean less lubrication as heavier oil thickness will provide better lubrication.. just use  double grade oil for peace of mind.if you use the engine for long in a summer day dont use thinner  oil

[Crossy]

9 hours ago, kickstart said:

these little engines are pushrods

Nope. It's overhead cam.

 

 

[Crossy]

10 hours ago, farmerjo said:

Any reason you can't use a heavier grade of synthetic oil in it to keep it cooler and use less oil as it is.

Just asking.

I'm not sure how well a heavier oil is going to work in a splash-lubricated engine.

 

It's not just burning oil, it's showing signs of 10 years of abuse, difficult starting, spluttering to a halt after a while. Time for it to have some love.

 

The more I look at this little baby the more amazed I become at just how few parts are actually needed for a 4-stroke engine compared with the last single I re-built (my old Matchless 250) many, many moons ago.

 

One of these:-

Definitely a thumper, in top gear a power stroke every telegraph-pole. No, the hairy object is not me.

 

[NonthaburiBear]

7 hours ago, Crossy said:

I'm not sure how well a heavier oil is going to work in a splash-lubricated engine.

 

It's not just burning oil, it's showing signs of 10 years of abuse, difficult starting, spluttering to a halt after a while. Time for it to have some love.

 

The more I look at this little baby the more amazed I become at just how few parts are actually needed for a 4-stroke engine compared with the last single I re-built (my old Matchless 250) many, many moons ago.

 

One of these:-

Definitely a thumper, in top gear a power stroke every telegraph-pole. No, the hairy object is not me.

 

nice bike & i tot its was Chewbacca

[billd766]

12 hours ago, Crossy said:

Nope. It's overhead cam.

 

 

 

Where did you find that link please?

[Crossy]

7 minutes ago, billd766 said:

Where did you find that link please?

https://rentamaxcr.com/manuales/GX35 armado-calibracion.pdf

 

[billd766]

2 minutes ago, Crossy said:

https://rentamaxcr.com/manuales/GX35 armado-calibracion.pdf

 

 

Thanks.

[Crossy]

4 minutes ago, billd766 said:

Thanks.

Loads more useful stuff here https://rentamaxcr.com/content/9-soporte-tecnico

[billd766]

4 hours ago, Crossy said:

Loads more useful stuff here https://rentamaxcr.com/content/9-soporte-tecnico

 

Thanks again.

 

I no longer cut the grass and scrub but spend the time cleaning, maintaining and repairing the Honda and the 2 strokes from the assaults of the guy who cuts the grass

[Crossy]

I think an update is in order.

 

Nipped into the Rangsit farm place on my way to work yesterday (yes muggins got lumbered, again). Picked up a carb and a piston kit (he didn't have the rings alone) along with a tube of silicon RTV, cost 1k Baht.

 

This morning sat down with the beast and the tools, lots of allen screws later we have a kit of bits. It came apart easily, no real need for a shop manual. The only bump in the road to disassembly was my inability to get one of the crankcase bolts out even after applying rather more heat than I was comfortable with, ended up drilling the head off after I rounded the hexagon. Needs another trip to the farm place to get a replacement (they're not open on Sundays), currently there's a regular M5x30 bolt in there (which in reality will likely be just fine but best to do it properly).

 

Valves out, no valve spring compressor so the old trick with the spanner and body mass did the job, valves and bore look fine. Deglaze the bore with a one-armed flap wheel as described in an earlier post and put the valves back in. Decoked the head with a wire brush in the Dremel.

 

Discovered that the existing gudgeon pin is shrink-fit in the con rod. Decided that the existing piston looked fine so just gave it the new rings and a decoke.

 

Time to put it back together by reversing the disassembly procedure ? The piston went in surprisingly easily, looks like the bore has a lead-in taper ?

 

I don't have a torque wrench so everything tightened by feel, but there is no separate head to warp so I don't see any real issues.

 

100ml of oil added (with a 50ml syringe), half a tank of fuel, prime, half choke. Bu99er me, it started on the second pull. Once it burned off the oil I used during assembly no smoke or oily smells. 

 

Result!

 

Topped off by fabricating a 35-26mm tube joiner to replace the plastic one that went the way of all plastic things in Thailand. A 1" to 3/4" PVC reducer with a lengthwise slot cut and a bit of heat to open it out to fit. Add a couple of jubilee clips and some black spray paint (so it looks less like what it is), bingo!

 

Time for a (IMHO deserved) beer!

 

 

 

 

 

[billd766]

1 hour ago, Crossy said:

I think an update is in order.

 

Nipped into the Rangsit farm place on my way to work yesterday (yes muggins got lumbered, again). Picked up a carb and a piston kit (he didn't have the rings alone) along with a tube of silicon RTV, cost 1k Baht.

 

This morning sat down with the beast and the tools, lots of allen screws later we have a kit of bits. It came apart easily, no real need for a shop manual. The only bump in the road to disassembly was my inability to get one of the crankcase bolts out even after applying rather more heat than I was comfortable with, ended up drilling the head off after I rounded the hexagon. Needs another trip to the farm place to get a replacement (they're not open on Sundays), currently there's a regular M5x30 bolt in there (which in reality will likely be just fine but best to do it properly).

 

Valves out, no valve spring compressor so the old trick with the spanner and body mass did the job, valves and bore look fine. Deglaze the bore with a one-armed flap wheel as described in an earlier post and put the valves back in. Decoked the head with a wire brush in the Dremel.

 

Discovered that the existing gudgeon pin is shrink-fit in the con rod. Decided that the existing piston looked fine so just gave it the new rings and a decoke.

 

Time to put it back together by reversing the disassembly procedure ? The piston went in surprisingly easily, looks like the bore has a lead-in taper ?

 

I don't have a torque wrench so everything tightened by feel, but there is no separate head to warp so I don't see any real issues.

 

100ml of oil added (with a 50ml syringe), half a tank of fuel, prime, half choke. Bu99er me, it started on the second pull. Once it burned off the oil I used during assembly no smoke or oily smells. 

 

Result!

 

Topped off by fabricating a 35-26mm tube joiner to replace the plastic one that went the way of all plastic things in Thailand. A 1" to 3/4" PVC reducer with a lengthwise slot cut and a bit of heat to open it out to fit. Add a couple of jubilee clips and some black spray paint (so it looks less like what it is), bingo!

 

Time for a (IMHO deserved) beer!

 

 

 

 

 

 

My hero.  ? ? ?

[Crossy]

1 minute ago, billd766 said:

My hero.  ? ? ?

 

Hardly, but it does show that these little engines are not rocket science, any reasonably competent DIYer with a decent toolkit can rebuild them in a weekend.

 

Of course, the local "small engine man" could also do it, but there's no satisfaction in that. The Rangsit farm man thinks I'm a crazy farang 'coz I buy all sorts of parts from him. He's happy to sell of course and always says "if you have problems bring it here", I haven't yet.

 

It actually felt good when it started and I am Madam's hero after I told her it was being donated to the family jungle ?

 

[Crossy]

24 minutes ago, Arjen said:

Good job!

Two beers is also fine!

Arjen.

1

Hmmm, there are five empties sitting by my desk right now (cans not bottles) 

 

It's peeing down and the power just went off, genset running ? 

 

I expect the neighbours to arrive soon wanting to watch TV and drink my alcoholic beverages ?

 

EDIT Power returned before neighbours arrived ?

 

 

[billd766]

3 hours ago, Crossy said:

Hardly, but it does show that these little engines are not rocket science, any reasonably competent DIYer with a decent toolkit can rebuild them in a weekend.

 

Of course, the local "small engine man" could also do it, but there's no satisfaction in that. The Rangsit farm man thinks I'm a crazy farang 'coz I buy all sorts of parts from him. He's happy to sell of course and always says "if you have problems bring it here", I haven't yet.

 

It actually felt good when it started and I am Madam's hero after I told her it was being donated to the family jungle ?

 

 

Sadly at 74 quite a few physical things are beyond me now. Up until this year I have managed to cut the grass and scrub on our land, up at my wife's shop and my neighbours land. About 2 or more rai, but this year my body doesn't want to do it anymore without giving me pain so I have found a Thai guy to do it for 1,500 baht a month.

 

Whilst he isn't too bad, he is not too good either and the cost of replacement parts has gone up for me.

 

The only other male apart from me between the 2 houses is my 14 year old son and I am not sure if he is up to it yet. In 4 years time he will be leaving us here in rural Khampaeng Phet to go to Tech or Uni elsewhere to learn for his future life.

[farmerjo]

Crossy,would be great if you could put a hand held temp gun on it to see what the operating temperature is.

What oil grade did you use?

[Crossy]

8 hours ago, farmerjo said:

Crossy,would be great if you could put a hand held temp gun on it to see what the operating temperature is.

What oil grade did you use?

Sadly Joe I don't have a non-contact thermometer.

 

It got the same oil as our other small engines GE Plus 20W-50 (cheap oil from Tesco) everybody seems happy on it, slightly thicker than the recommended 10W-30 or straight 30.

 

[Crossy]

On 8/26/2018 at 10:56 AM, Crossy said:

The only bump in the road to disassembly was my inability to get one of the crankcase bolts out even after applying rather more heat than I was comfortable with, ended up drilling the head off after I rounded the hexagon. Needs another trip to the farm place to get a replacement (they're not open on Sundays), currently there's a regular M5x30 bolt in there

Replacement bolts, with washers, a whole - wait for it - 5 Baht each (I bought a set of 4, don't want to risk damaged heads on the ones I took wrestled out).

 

They were actually about 4mm too long, so activity with the hacksaw and bench grinder sorted that.

 

Task now complete ?

 

[Crossy]

Actually the task wasn't complete. 

 

As others have noted the ignition coil is also a weak point. The coil in question was fine for 20-30 minutes at which point things stopped dead.

 

New coil was 500 Baht, strimmed away all Sunday afternoon.