Anyone here got a Bosch Rotak 40 mower?

[T i m]

Hi All,

Trying to help an elderly couple with their 'Bosch Rotak 40' mains mower where the sprung loaded top flap has become unsprung:

Now it looks like that spring should have an arm that goes though that slot on the flap just under the spring itself and onto the body somewhere and looking at that picture again I think the spring has been put back on the wrong way round (eg, the lower bent arm should be on the left and the right / vertical part of the spring that attaches to the flap would be more vertical).

(Thinks) It now makes sense ... the spring came off, she found it on the lawn and put it somewhere safe in the shed but couldn't see it when she went to show me earlier. I couldn't see where another spring would go and 'of course' it's 'the' spring that someone has tried to put back on.

Now looking on the parts diagrams it looks like the spring is supposed to be straight (the arms at 180 Degrees from each other) and I guess there is a slot for the lower half of the spring to slot into?

So, does anyone have such a beast who can confirm my thoughts re the correct fitment above and have you had similar problems with yours?

Cheers, T i m

[Chris Bartram]

Does this pic from my Rotak 32 help?

[Tim+]

I think the spring has been hit by the blade and acquired an extra bend. The long straight end is clearly meant to be located in the "tunnel" in the flap. If the spring was threaded on to the pivot the other way around the end with the loop on it might rest in the recess in the mower body. The notch in the flap would suggest that the looped end should be "outboard" rather than inboard.

You may be able to get rid of the blade induced kink if it's not too badly damaged but a new spring is probably needed.

Tim

[T i m]

I think it does, it confirms my thought that the vertical part of the spring probably (on the one I'm dealing with) doesn't lay flat against the lid as per my picture but away from it as in yours.

That then would match the reply from Tim+ that followed yours. ;-)

Strangely, the image of the new spring in the advert above doesn't seem to match the exploded diagram at the bottom of the same page but if it's purpose it so spring the cover closed, makes more sense as per the advert pic?

I don't know how the spring came to come out or how it got bent (other than by Tim+'s suggestion of it being hit by the blade) but I think a new one would be preferred over trying to straighten the old one (it being spring steel etc).

Cheers, T i m

p.s. Thanks for taking the time to take the pic and reply Chris. ;-)

[Yvonne]

I have one of these and scratched my head the first ttime I reassembled it after changing the motor.

The hinged flap at the rear is held closed under tension by the spring. One arm of the spring is anchored in the hinged flap and the other end slots i nto a vertical recess in the body. This recess is really a slot open on one side and is about 1.5" square and about 6" deep.

This recess is behind the arrow in this picture:-

l

To get this arm into the slot correctly, take off the main cover( with the rear flap still attached). Reassemble by locating the front of the cover i n the front of the chassis of the mower. Dont screw it down yet.

With the whole cover assembly located at the front (and flap still attache d to it), pull the loose arm of the spring so that the torsion spring is tw isted under tension. That is open up the arms s that they are at 180 degree s apart. Then whilst it is still under tension, push the loose arm vertica lly down into the vertical slot.

It's a wee bit tricky but you will get the hang of it after a couple of tri es.

Then screw the cover down and you are done.

[T i m]

You are probably right.

But the other way up (the wire away from the flap itself, as per Chris's model / picture)?

Agreed.

If I was to try I think I'd straighten it I'd do it in a vice or press, rather than trying to manhandle it into the right shape but (as you say) if they are cheap, it's probably not worth it.

I mean, what made it come off in the first place?

Cheers, T i m

[T i m]

Ok.

That makes sense as the lady said without the spring it sprays grass in her face. ;-)

Cool.

Brilliant, thanks. ;-)

Great explanation as I know what we are trying to do (insert the spring in the slot whilst it's trying to shut the flap).

At least I know what to expect.

Sweet, thanks. The 90 Yr old and dying of cancer lady was told by a lawnmower repair man that it probably wasn't worth doing. ;-(

While I am there, are there any filters in the motor air cooling path as I found those were completely blocked on a Flymo I stripped and cleaned the other day?

Cheers, T i m

[T i m]

I think it does, it confirms my thought that the vertical part of the spring probably (on the one I'm dealing with) doesn't lay flat against the lid as per my picture but away from it as in yours.

That then would match the reply from Tim+ that followed yours. ;-)

Strangely, the image of the new spring in the advert above doesn't seem to match the exploded diagram at the bottom of the same page but if it's purpose it so spring the cover closed, makes more sense as per the advert pic?

I don't know how the spring came to come out or how it got bent (other than by Tim+'s suggestion of it being hit by the blade) but I think a new one would be preferred over trying to straighten the old one (it being spring steel etc).

Cheers, T i m

p.s. Thanks for taking the time to take the pic and reply Chris. ;-)

[GB]

It might not be worth doing commercially, actually. If he has to locate and order a specific part, then puzzle out the non-obvious reconstruction, that could take a couple of hours. He needs to earn a living, and he has premises to pay for. It could easily be a 50 quid repair on an old mower.

Plus VAT, if you want a receipt. ;)

It's nice of you to take the time and trouble, but I'm not sure the repair man was wrong.

Please let us know. I have a Bosch, and it seems to overheat more now than when new.

[T i m]

Of course.

Yeah, I wasn't really questioning the cost justification when seen as a commercial solution, just that it was a shame that something like that might be written off for the cost of a flap spring.

Will do. ;-)

Cheers, T i m

[Yvonne]

The answer is YES. You will see them when you take off the entire upper cover assembly - which you have to do anyway to get the torsion spring back under tension. See my earlier post.

[Yvonne]

OK, are we all sitting comfotably?

The photo I supplied last night was taken in the dark but I have uploaded two which clearly show the correct layout.

The key thing is that the spring ( in the OP's original photo) is the wrong way round on the black plastic spigot. It should be turned round 180 degrees so that the short arm is on the left.

The short arm with the loop is clearly shown going vertically down into the slot.

The sideways bend is likely human intereference and most ulikely due to it hitting the blade at any time. Even withis slight bend the short arm will go into the slot OK.

My forensic conclusion is that the entire upper cover was, at some stage, removed and whoever did it did not work out how to slott the spring arm under tension into the vertical slot.

Min's a Guinness, please.

[The Natural Philosopher]

Sadly photobucket simply never has worked on my setup.

If I disable AB+ I get adverts, but still no pictures.

[T i m]

Thanks, I'll check that out as well then (and goes along with 'while I am there'). ;-)

Cheers, T i m

[GB]

Oh so true. Things used to get repaired in the past, but I suspect they were way more expensive (always allowing for inflation, ofc). Maybe what we need is a massive hike in VAT on goods, but not services?

[GB]

Same here - I use chrome. The trick is to let the page start to load and then hit the stop loading button. Takes a couple of tries to get the timing right. Plus I am aided by having quite slow adsl.

[Capitol]

Interesting. It works for me on this occasion, using Ubuntu 10.4, Seamonkey 2.1, with java script enabled.

[T i m]

So dark you forgot you hadn't cleaned the mower for a while. ;-)

Excellent, both pictures come up fine in this 10+ year old XP. ;-)

I think that had been confirmed upthread somewhere but would good to see the pictorial version (so thanks for taking some more).

Agreed.

Ok?

I didn't try (it was a quick look and photo and was raining outside) but will.

Quite possibly but such hasn't been mentioned (not to say it didn't happen of course).

I'm afraid it's only tea a biscuits but have one on us. ;-)

Cheers, T i m

[T i m]

'Trick'? Click on link and it opens ... (I happen to use Firefox).

Maybe my OS / Browser combo is 'just compatible'. ;-)

Cheers, T i m

[Andy]

replying to T i m, Andy wrote: Without your question on here Tim and the replies from Chris ,Yvonne, GB, Rod Speed, The Natural Philosopher & Capitol, I would have struggled even longer on my Bosch Rotak 36! Thank you to you all, Andy.