Problem with Petrol Mower - Mountfield SP414

If this is your actual lawn mower then the image below shows the spark plug cover, this just pulls off from the small L shape part (can be quite tight) and reveals the spark plug, which then requires a box spanner to remove.

 

Hi Scudo I have tried to pull this metal cover off and it will not budge and the limited space that I have with the plastic cover around it makes it much harder anyway. Stupid question am I pulling from the black cable at the top ?

Also reading the online page I found I think it is talking about draining the fuel out completely which is what I have already done, I thought it was refering to draining old fuel from the carb itslf. Shame I cannot add the link .

Thanks

TimCS

 

No, Pull from the lower end straight out...

If it were me I would clean the carb, I have done a few so am comfortable with it, it is difficult to instruct on a forum but utube videos should cover as most are similar. Just be careful with any seals/gaskets as they damage easily, also when `rebuilding` be careful not to overtighten any screws as it is easy to strip the threads on the aliminium.

 

@Scudo - your advice is absolutely brilliant and the illustrations are incredibly informative. Seriously mate, credit where credit is due

Just hoping you you don't highlight the upper part of the ignition lead in purple

 

Hi Scudo thanks for the clear diagram on how to do this. Also with regards the carb from my pictures can you possibly indicate where to start ? Am I taking the top over off to start with ? The instructions I mentioned were really talking about the carb float bowl. I have copied this section to text , this is the page in question :

 

First thing you should do is disconnect the lead from the spark plug, I would then remove the plug and check its gap and also that it is `sparking`
The top cover should not need to be removed.

1st option: Carb, if possible (space permitting) remove angled screw on the carb to drain carb.

Then there should be another screw on the bottom of the carb, take this out and hopefully that will be the jet for the carb, clean out the jets with very fine wire or pressured air, be careful with wire so not to `widen` the jet size. TAKE PICTURES AS YOU GO ALONG FOR REFERENCE.

2nd option: To remove carb....
Remove cover (1)
Remove air filter (2)
Unclip hose (3)
Undo bolts (4)
Undo hose (5)
Unhook springs (6)

This should allow you to remove the carb (7) and give better access.
Check for any damage to seals / gaskets they may need replacing.

Take pictures at every stage for reference.

 

Hi Scudo thank you for this detailed and helpful reply! I had already drained the fuel using the screw nearest to me but I had not done anything with the other screw that is behind it. Is that the screw you are referring to here :

Then there should be another screw on the bottom of the carb, take this out and hopefully that will be the jet for the carb, clean out the jets with very fine wire or pressured air, be careful with wire so not to `widen` the jet size. TAKE PICTURES AS YOU GO ALONG FOR REFERENCE.
Click to expand...​

I will see how I go and how confident I am with taking it all apart but I will first go about looking at the spark plug .

** EDIT **
You mentioned not to remove the top cover from the spark plug are you referring to the metal cover? if so how would I remove the spark plug if I do not remove this ?

Thanks

TimCS

 

By top cover I thought you meant the large black cover on top of the machine. Yes remove the spark plug cover.

 

Hi Scudo thanks for clearing that up. As for the screw you mentioned is this the other screw that in the case of this mower is the one furthest away from the front ? I have already drained the fuel out of the mower using the screw nearest to the front.

Well I have tried to remove the cover from the spark plug and cannot with the limit space and grip around it. Sorry for this but I cannot remove this cover without damaging the spark plug itself.

Thanks

TimCS

 

@timcs - the HT/spark plug lead cap/cover should pull away off the spark plug as @Scudo illustrated in his pics. It appears to be shielded but it is just an outer layer for protection.

You should be able to pull it out with fingers or (gently) with pliers. You wont damage the spark plug, trust me... but taking the HT lead casing apart is unecessary and may cost you a few quid. All you need to do is pull the plug lead out to get to the spark plug.

 

Hi MowerMan , I understand the angle and direction of what Scudo has shown but there is no give with this and considering the limited space around for the hand to fit , I cannot get any grip on it at all . Pulling the plug lead out is as difficutl to do as the case as there is no room for my hand to get to it.

Thanks

TimCS

 

Try removing the black cover (1) it may give better access.
Does the plug cover swivel slightly in any direction (white arrows)
Maybe get a piece of ribbon or similar behind it at the lower end and pull that.
That plug cover has to come off it is just a push fit.

Quote.....
"To remove the spark plug wire or boot, turn the connection back and forth (clockwise and counter-clockwise) to loosen the bond."

 

Hi Scudo

Again thanks for the input, on this , yes the plug does swivel in the directions you show and I have tried to use this to get my hand around it . I will try your suggestions but it may not be until this weekend coming up now . So I will report back after then.

Also your thoughts on the carb screws, am I unscrewing the one furthest from the front ?


Thanks

TimCS

 

Yes the one furthest from the front. hopefully that will release the bowl and reveal the jet.
Another option would be take the carb off and ask a garage or lawnmower shop if they will clean it.

Sparkplug: if the boot swivels then it is not seized, maybe using a piece of sandpaper will give a better grip. I have never used one but apparently there are tools to aid getting the boot off, same principal to my suggestion of using a piece of ribbon or belt.

If I remember correctly I could only ever get a finger & thumb on the sparkplug boot, never could get fingers all around the boot.

 

Hi I wanted to put a link to maplins where I have got an air duster from but as yet I still cannot post with a URL. So if you go to maplins website and look for air dusters, there is a brand called AF sprayduster 87ml .

I took a plunge and bought these , yes I could have gone somewhere else and got some cheaper, but just wanted to make sure that they are safe to use with the mower.

Thanks

TimCS