Oil leaking from spark plug hole

[Shaffick]

Hi all

I would just like some advice on a free chainsaw that I came across. It's a cheap Chinese saw so I'm not asking for any miracles. 

The chainsaw wouldn't start at first. I noticed that the spark plug didn't look seated correctly and looked slightly cross threaded. I managed to re seat the plug which now looks flush and is very tight. The threads don't appear to be stripped. 

I noticed that the original toggle kill switch was useless and I replaced it with a different type of switch. 

I got the saw running and after about 5 mins I noticed a very slight oil leak coming from where the spark plug is. The spark plug is a used one.

My question/s is what is causing this? and would a new spark plug with a better washer solve the problem?. Thanks.

[Mick Dempsey]

You need to carefully hold the rear handle, release your hand from the chain brake. Swing it round and round then release it at maximum velocity into a bin at the local tip.

[Shaffick]

Another typical useless answer from another chainsaw snob. Must be a small penis thing over compensating with a large Husqvarna 🤔 

[spudulike]

Cheap and cheerful chainsaws are rarely "cheerful".

I would say that the plug thread is damaged and allowing leakage up between the plug and plug hole. If you put a mix of detergent and water around the plug and pull the saw over slowly, you are likely to see bubbles forming around the plug proving the point.

Probably not worth worrying about and may just carbon up in time. If the saw was a better make then helicoiling it would be the sensible option.

 

[Will C]

I have seen some one cover the plug threads in chemical metal and wind it in. Saw was running fine after, what happened next time it needed a plug I would guess goes back to micks offering, cheap saws are disposable unfortunately (normally very quickly).

[Shaffick]

6 minutes ago, spudulike said:

Cheap and cheerful chainsaws are rarely "cheerful".

I would say that the plug thread is damaged and allowing leakage up between the plug and plug hole. If you put a mix of detergent and water around the plug and pull the saw over slowly, you are likely to see bubbles forming around the plug proving the point.

Probably not worth worrying about and may just carbon up in time. If the saw was a better make then helicoiling it would be the sensible option.

 

Thanks for your advice. I'll try the detergent trick. Would the head need removing if I were to helicoil the thread?

[Shaffick]

31 minutes ago, Will C said:

I have seen some one cover the plug threads in chemical metal and wind it in. Saw was running fine after, what happened next time it needed a plug I would guess goes back to micks offering, cheap saws are disposable unfortunately (normally very quickly).

Cheers Will. I'll try that. I'm fully aware that this is a cheap saw. It's just a little project.

Speaking of my mate Mick, I pulled a chainsaw out of a skip and changed the perished fuel lines which cost only £3 and sold it for £65. 

I went to a car boot last month and picked up 2 chainsaws for £8. One was a McCulloch and the other one from our far eastern friends. Got them both running. Sold them both for a combined price of £110. 

These saws may not be to people's liking on here but there's definitely a market for them and they will sell.

I'm definitely leaning towards the damaged threads theory now.

Edited August 1, 2023 by Shaffick
Wrong spelling

[spudulike]

21 minutes ago, Shaffick said:

Thanks for your advice. I'll try the detergent trick. Would the head need removing if I were to helicoil the thread?

I have helicoiled heads with them in place but it takes good preparation, skill and care.....stuffing the combustion chamber with cloth, forming a cavity in the cloth to take the tap, using heavy grease to catch all the swarf etc

[Shaffick]

4 minutes ago, spudulike said:

I have helicoiled heads with them in place but it takes good preparation, skill and care.....stuffing the combustion chamber with cloth, forming a cavity in the cloth to take the tap, using heavy grease to catch all the swarf etc

Ok mate. Thanks again. 

 

[Muddy42]

Maybe try a new sparkplug with crisp threads. New sparkplugs will also have a stronger spring washer? Use grease.