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Collection, Preservation and Display of Old Lawn Mowers

What Oil?

Just waiting on delivery of a governor spring for my super punch (cast iron) to arrive an i will try an start it tonight, before i do that, i woudl prefer to change the oil - as god knows how long it has sat in there

Anyone any ideas what grade will suffice?

many thanks


mudcow007 Thu, 31/03/2016

Its ok i have been able to track down some SAE30 oil, which im led to believe will be fine


wristpin Thu, 31/03/2016

An SAE 30 will be fine but before you change the oil, drop the sump and thoroughly clean it out to get rid of all the old sludge and whatever else is lurking in there.  Your new oil will stay cleaner for longer.

mudcow007 Thu, 31/03/2016

Dammit, should have looked on here before i changed it :(

the stuff that came out resembled treacle...poor engine

Replaced the plug, cleaned the lead up with scotchbrite = blue spark - which is nice

I cant figure out the throttle linkage, when you move the throttle on the handlebars it doesnt seem to effect the carb/ engine

Granted i haven't had it running yet, but cant see how it would effect the engine/ revs as it stands

fuel tap is leaking, was gunged up so cleaned it out with brake cleaner, now it slides out great but, you can blow past it (new fuel line)

oh something odd....en exhaust has been crimped on the end? im guessing in an attempt to quieten it down?


wristpin Fri, 01/04/2016

That exhaust is definitely " interesting" ! Here's one I did recently.

The throttle arrangement is OK although the governor Spring may not be precisely correct - but will probably work reasonably well .  Basic operation is that the air moved by the flywheel fins acting on the  governor  vane will attempt to shut the carburettor butterfly. The throttle lever on the handlebar will apply tension on the spring in opposition to the vane and attempt to open it. The result should be the engine running at its governed speed and able to react to changes in load.

If you have a brass fuel tap , the plungers are available as replacements and there's even one internet seller offing replacement corks to fit your plunger.  Some people suggest  soaking or boiling the plunger to swell the cork but I've never had much luck doing that. If it's a plastic tap it's a throwaway item and there are plenty of replacements on offer.

mudcow007 Fri, 01/04/2016

Thanks Wristpin

I can confirm its a brass plunger on mine, screwed basically to the bottom of the fuel tank.

That makes sense with the linkage, will see if it fire up an see how it runs

Another issue i found late last night is the lever on right of the deck (if you were standing at the handlebars) wont move....I havent opened the side of the case yet, I suppose its possible its just gunged up - hopefully

This lever switches it self propelled or manual doesnt it?

wristpin Fri, 01/04/2016

Standing behind the machine I would expect it to be on the left!

Yes it engages and disengages the drive to the rear roller. Sometimes, if the roller has end float (sideways movement) it can be difficult to obtain correct adjustment , Best to eliminate end float before struggling with adjustment.

mudcow007 Sat, 02/04/2016

(scene from Frankenstein) It lives muhahahahah (evil laugh)

Put some fuel in the old girl tonight an it fired on the third go!

Fuel does indeed leak (really badly) from the fuel tap, so that will need resolving

Also the engine was really really racing, possibly due to carb settings? I only have the manual for the Suffolk Punch, hopefully the carb settings are the same for that as mine....? can someone possibly confirm please?

Oh i think i have figured out the lever for self propelled etc, there is a bracket  that was not allowing the lever to move, I slackened that off now i can select self propelled!

quite a productive afternoon

wristpin Sun, 03/04/2016

The carb on your machine will be basically the same as your manual so the sme principles of adjustment should apply.

The racing will be more likely to a governor issue than carburettor settings. Once that is sorted you can fine tune the carb. With the handle bar control in the slow position there should not be any tension in the governor spring and the crank with the stop screw on the carb butterfly shaft should be free to move to the shut position  - unless, in the absence of a governor spring, someone has wound the screw right in to hold the butterfly open .


mudcow007 Mon, 04/04/2016

Thanks Wristpin

Governor has just arrived, either the one fitted to my Punch is really really stretched (most likley) or the new one is too short, but will have a better idea tonight when i fit it.

Removed the fuel tap plunger an have left it in a sealed container of petrol to see if it does indeed swell at all, failing that will try an track down some cork.

had a quick look at  how to remove the blades over the weekend, the bottom blade screws are stuck fast. I have left them covered in oil - the worry is I will wreck the heads trying to get them off

So on the agenda are....

sort out the governor/ carb to run at correct speed (have ordered a rev counter that connects to the spark plug to give an rough idea of revs)

stop fuel leak

remove blades to be sharpened

fit some sort of exhaust/ muffler (thoughts on something like this

paint and enjoy

wristpin Mon, 04/04/2016

You may not have to remove the bottom blade from its carrier (sole plate) If it has the correct lipped blade there may be enough "meat" on it to take a skim. Even if a new blade is fitted it is good practise to skim it once fitted to remove any inaccuracies in manufacture .

The cutting cylinder and sole plate drop out as a unit after removal of the drive sprocket and two hex head screws holding it into each of the chassis side plates , Slackening the two tie rods that run between the side plated will help create a bit more " wiggle room".

The whole job will be easier if you remove the engine to make the machine more manageable and even remove the engine mounting platform.

If you do need to remove the bottom blade the first thing to do is to maximise your chances of getting the screws out . Always envisage the worst case scenario and do every thing possible to avoid it!

First clean up the slots in the heads with a hacksaw blade or Dremel.  Then , if you have a propane torch or even better access to oxy acetylene heat each screw head to red heat and allow to cool. The best tool for undoing them is a hand held impact driver which exerts a turning force while keeping the bit firmly in the slot.. Failing that careful tapping the head round with a punch or chisel..

The fall back option is to weld a bit of scrap to each screw head . This puts more heat into the screw and gives you something to turn it with .  

Having done it for a living I always worked on the principle that they were going to fight but time spent on a logical measured approach was far better than having to launch a recovery operation!



hillsider Mon, 04/04/2016

Good advice re the bottom blade and cylinder but re the link to the silencer on the video I am sorry to say that I don't believe it to be a viable solution.

You would do far better to look at fitting one along the lines of that shown in wristpins photo, a Briggs and Stratton silencer if I am not mistaken.

wristpin Mon, 04/04/2016

Yes , its a pattern part Briggs , carefully bent to clear the carburettor. I have to admit to destroying a couple while defining "carefully"; fortunately I had a few that hadn't cost a much from a job lot.  . Maybe more sensible to use a plumbing bend and forget the bending but it looks better when close coupled.

mudcow007 Tue, 05/04/2016

Awesome guys thank!

updates to follow

Thanks once again

mudcow007 Tue, 12/04/2016

Evening all

few updates an questions unfortunatly

I have bought and fitted a Briggs an Stratton exhaust, i found it fowled on the carb/ inlet so fitted a 1/4" elbow which worked a treat.

Also niknaks like a new pull cord handle (and rev counter)

So first pull an it runs, but fast. Rev counter said about 2200rpm !!

With the engine off there is little tension in governor. so im thinking its the carb (settings)

The governor spring was replaced but looks a little different from the one i removed, i put this down to the old having become stretched. the spring is also in the hole to make it the slackest (if that makes sense)

I have just found all the screw settings for the carb so will do that tomorrow, I might strip the carb down again

Anyone any thoughts or ideas?

oh just to add, I pulled the plug after it had ran for 30 seconds an it was as black as a witches hat - you quite probably a bit rich?

wristpin Tue, 12/04/2016

From memory there were three different governor rods with different springs to match. There's a fair chance that the machine has seen some changes over the years so the pragmatic answer is to do what is needed to obtain the desired result..

Idle rpm - low enough to disengage the clutch but high enough to sustain a steady idle. So long as the throttle / governor spring combination is allowing the throttle stop screw to contact the abutment on the carb you can make alternative adjustments to the idle mixture screw and the throttle stop screw to achieve the desired result - steady idle and clean acceleration when the throttle is opened.

Top / working speed. The chances are that with the throttle wide open you will be running after the machine so top no load speed is fairly academic - just learn to balance the throttle to the load and working conditions. The main jet setting is the usual undo it until the exhaust now goes heavy or the engine 8 strokes then screw it back in until it start to falter . then go for the mid point.

Your black plug may be just from an over rich mixture but a bit of oil burning may be contributing.

mudcow007 Wed, 13/04/2016

Thanks wristpin

So, had the morning off work so i got tinkering, pulled the carb off again an stripped it down, nothing untowards except a bit of muck in the bowl.

rebuilt, main screw set to 3/4's of a turn, air screw was 1 & 3/4. Then i noticed the bottom of the tank was wet - looks like its leaking from behind the lugs of where it mounts to the cowling.

i refitted the old governor spring an the throttle seems to actuate much better - so maybe the new spring is wrong?

tried to start the old girl, it was alot more reluctant than normal, but if it had been mega rich it would be really easy. eventually got going then stalled, tried to restart an snapped the pull cord grrrr - so i left it like that

wristpin Wed, 13/04/2016

Think that you've got the jet " turns open" the wrong way round . The top screw 3/4 ish and the big one on the float bowl midway between heavy and faltering.

Tank leaking due to strained spot welds where the bracket is joined  to the tank. Usual cause is the machine being lifted by the tank as its the easy thing to get hold of. I used to seam braze right round the bracket having de- gassed the tank first!

mudcow007 Thu, 14/04/2016

oh...that would explain the reluctance to start, thanks once again wristpin

I will bring the tank in to be brazed in work. I work with silversmiths, so will probably be silver braze - only the best for my Suffolk!

On a slightly different topic, could someone explain the hand clutch to me please, I was under the impression that with the clutch disengaged the engine is free revvng an not under load (blades dont spin) clutch engaged, the blades spin

regardless of the clutch position, my blades spin?


wristpin Thu, 14/04/2016

By hand clutch I presume that you are referring to the pull out dog clutch to the left of the centrifugal clutch drum.  There has been extensive discussion of this problem and its possible causes and cures on the forum over the last few weeks - search on user name Biffa. See how you get on and report back!


mudcow007 Thu, 14/04/2016

Cheers Mr Pin

work on Charlene ( what i have christened my punch) will have to go on hold. Some delightful cherub has tried to break into my shed, I presume to steal my motorbikes :( bad times....

updates on Charlene to follow

mudcow007 Thu, 21/04/2016

A little update.

I have finished replacing my front roller. I used a hardwood called Iroko. I did plan on using oak, but I had more Iroko laying around plus its a bit lighter than oak.

Fuel tank leak is getting brazed as i type. Turns out the fuel tank outlet (bit that is threaded for teh tap) is only lead soldered on, so when the leak was being brazed the threaded part fell off grr...Anyways this is now being resolved so hopefully wont be leaky any more

I started the old girl last night, left it running (fast) for about 5 mins an couldn't get it run without choke. It must be down to the carb settings i reckon.

updates to follow