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Collection, Preservation and Display of Old Lawn Mowers

Ransomes 20" Auto Certes - A few questions

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Hello All.

I have a couple of questions relating to the above mower.

1) My son and I are in the process of stripping it down but we were unable to remove the engine.  Three bolts came out fine but the one under the exhaust is slightly different as it seems to be a captive bolt coming up through the chasses.  This means that the engine cannot be simply slid away from the centrifugal clutch.  Are we missing something, or do we need to take the main drive shaft out to allow the engine to be lifted from this bolt?

2) Does anyone here know where I can buy a copy of the parts list / exploded diagram to help us along our way?

3) We have the chance of a grassbox from a Mk5 20" Marquis, will this fit the Mk3 20" Auto Certes, as ours is in really bad shape?  It looks similar but not sure of compatibility.

4) Ours has chassis rot right at the front edges above the roller.  Someone has also tried to repair it in the past but not very well.  I used to do a lot of bodywork on old cars when I was a bit younger so not afraid of the welder and so on.  Has anyone successfully managed to recreate the shape of the front end of these machines?  It's probably not worth the effort when it gets to this point, but it should make a good summer project for us.

Anyway I've ranted on for long enough so if anyone can help with these questions, it'd be very much appreciated.

Cheers,

Geoff.

Forums

wristpin Wed, 09/05/2018

PM sent,  but engine removal.

As you are probably going to strip the machine to a bare chassis, why not drop out the rear roller so you can remove the offending  bolt? I’m guessing that at some time the thread in the reinforcing bar under the top deck was stripped ant that putting a bolt up from below was an instant solution; but why not a helicoil?

Geoff Wed, 09/05/2018

Right, now that makes sense.  I'll drop the rear roller as you suggest and see what's hidden under there.

Forgive me for this question, you say that you've sent me a PM.  How on earth do I find my private messages.  cant see the option anywhere. 

 

wristpin Wed, 09/05/2018

Re PM. It should arrive in your email "in box" as a message from the Old Mower Club. To send one to another member posting on the forum just click on their username and select "contact".

Geoff Wed, 09/05/2018

That's great, thank you for clarifying.  And thank you for your PM too, I'll make some phone calls tomorrow.

Geoff Wed, 29/08/2018

Back on the Ransomes again after buying a used, but in good condition chassis, off a kind man on eBay.

Started stripping the old mower down and temporarily reassembling all the parts on the new chassis.  The only reason for this is to make the disassembly and reassembly stick in my head, or I'll forget!

I have a few disassembly problems that I need help with if someone could help please.  I also apologise if these topics have been covered elsewhere.  Simply put, I cant get these three cogs off in the chain case........

wristpin Thu, 30/08/2018

For cogs read sprockets!

Looks like  one of your images shows an Auto Certes rather than a Marquis and that someone has done a fairly crude amputation of the extended rear roller shaft. Presumably on the other end as well.

The sprocket on the top main clutch shaft is on a conventional right hand thread and unscrews anti clockwise. It will be **** tight.

the locking collar in the centre of the traction clutch also unscrews anti-clockwise . You really need to make or buy a peg spanner to engage the holes in the collar to do the job. Tapping it round with a punch is a very last resort .

As you've already removed the big nut on the Auto Certes rear roller shaft the sprocket  which engages the shaft with a parallel key may be drawn or levered off.

EDIT pic of a clutch collar undoing tool LCG1491

Geoff Thu, 30/08/2018

Thanks gents for the useful information.

I could easily make a tool like that I guess. Are the holes 30mm centres?  What are the hole diameters? Would it be best to make one of the pegs adjustable or best to keep them both fixed position?

By the way Chris, I've just finished reading your posts from start to finish in the link you sent.  That is a cracking writeup and what a smart looking machine you now have - the time and effort you put into it clearly shows in the finished article.  Spot on.

Cheers

Geoff.

wristpin Fri, 31/08/2018

You may have to exert  a considerable turning force on the tool so I would make it fixed.. Dimensions - you have the collar so just make it to fit! 

Geoff Fri, 31/08/2018

Fair point :)  I'll hopefully be able to knock something up this weekend.  I'll keep you posted. 

I just want to get round to looking at the engine as there is very little compression.  Hopefully it wont be too serious a problem.

wristpin Fri, 31/08/2018

Hopefully a valve job will restore some compression but bore wear is a bit more serious to deal with and rather dependent  on the extent of the wear and availability of oversize pistons and rings etc.