SC46 6 months in soil

[Brian Dorricott 1]

Hi guys

Quick search did not find me anything in forum but I suspect it's been asked before .

I lost an Arising Star about 6 months ago and yesterday the club mountain Man found it with its nose buried in soil , it took him 10 minutes to dig it out with 2 screwdrivers so pretty deep in soft soil . The airframe cost me £15 pound with a spare wing so no great loss but the engine was brand a new SC46 I very carefully ran in on the bench before using .

Question is how to clean it before getting a look inside ? The carb inlet is solid soil but it looks undamaged at the moment . Would jet washing the rubbish off first help or a gentle wash in sink with warm water and a toothbrush or letting it dry out first then cleaning it ? Obviously it has to be very clean before opening or even wd40 the screws etc . Any thoughts on best way to proceed from here while it's wet an muddy. Just a thought while do we search much closer in than where the actual plane crashed ? Do we think without our guidance it won't go far ? FYI it was 150 metres further into brambles than where we were looking. Usual proviso any help even mild Micky taken appreciated

[Denis Watkins]

when no one else is at home

put it in the dishwasher Brian

this works

some may be appalled

leave the glow plug in, and as you know, do not turn the motor over

the motor will get very hot in the dishwasher and self dry

No one must discover your motor in there

any slight water ingress is better than mud

Edited By Denis Watkins on 05/11/2018 09:43:52

[Jon H]

After that amount of time the crankcase will be full of crud and i suspect the bearings will be finished. I would pressure wash the outside and then strip down the engine cleaning each part before reassembly and fitting new bearings.

If you attempt the dishwasher method be careful as some dishwasher chemicals are not very kind to aluminium.

[Peter Miller]

Personally I would start off by washing the outside carefully in the sink with a tooth brush. as there will be a silencer on the engine this will have kept the crud out of the cylinder,

Remove the silencer and first check just in case any mud has washed into the exhaust port.

Not being familiar with dishwashers (Mine (me) uses a plastic bowl and two hands and a brush) I would suspect that there would be a possibility that the jets could push crud into the engine where more gentle cleaning will not.

Once the outside is clean strip it very carefully and check for any mud down the hole through the crankshaft.

The front bearing may have some grit in it. the rear one should be pretty safe.

[Paul Marsh]

Did the engine grow a bit?

[J D 8]

Lost models are always twice as far away as we think.

[Brian Dorricott 1]

Update

Cleaned in dishwasher scrubbed and it all became clear . Carb looks like a write off rusted too much , crankcase seems to have lost some metal towards the rear and the backplate is crumbling , head looks ok even glow still works . Hole in crankcase is the killer though but I have a serviceable crank , head , exhaust and liner/piston/connecting rod so not total loss as I have 2 more SC46s that might eventually need bits . Thanks for advice everyone.

On a slightly different note started my first 4 stroke yesterday Saito FA40a on test stand , what a revelation in smoothness and throttling compared with a SC46 ? The 2 strokes sound positively thuggish compared to the Saito , this started straight out of box idling away hardly any noise or vibration and all I did was a 3 turns out so not needle sensitive - think I might be a convert ! So what size to replace a 46 2s then ?

[Martin Harris - Moderator]

70

[Don Fry]

About a 70 4st, or to be a bit more accurate, I reckon a 70 4 st replaces a 52 2st.

[Jon H]

Brian if you arent too worried about the 46 you could just plug the hole with JB weld. It would be a bodge up but it would make the engine go again assuming the carb can be rescued. The white corrosion is something i experienced with an SC36 that was in the garage a few years. Its a nice example of why they are cheap, i have never had any other brand of engine suffer to that extent. Clearly not the finest materials used in the castings.

As for the 2st vs 4st question its not a direct size X = size Y as the engines deliver their power in different ways but generally i would agree say that a 50-70 would replace a 46 depending on the use. In a trainer a 50 4 stroke is more than enough, in something like an acrowot then a 60 or perhaps a 70 is likely to do the job better. If you do start using more 4 strokes dont under prop them as they are far better on bigger props.

[Jon Laughton]

Posted by Paul Marsh on 05/11/2018 19:57:58:

Did the engine grow a bit?

[CARPERFECT]

Brian Dorricott. If you need another SC 46 i have a spare. Had very little use, looks like new. Yours for £45, posted, and i also have a OS 46 AX also in near perfect condition £60 posted, Both not used anymore as i only fly 4 strokes now

 

Edited By CARPERFECT on 06/11/2018 22:14:54