Skip to main content
Collection, Preservation and Display of Old Lawn Mowers

Webb 18” motor mower model AB1476

Enter a word or two to search the forum section and click the Search Forum button.

Hello

i have just acquired a couple of Webb mowers, a 18” motor mower AB 1476 and an old 24” Webb ride on. 18” has B&S 2.5hp and 24” has the 5hp B&S. 

Is it possible to get a copy of service or owners manual to help get these back to life. Both one owner from new and both have not run for some years but look in good but dusty condition!

i will check the mowers section the site

Any info gratefully received

Thanks

Forums

Henno Tue, 13/08/2019

Welcome!

The manual for the AB series can be found in the Technical Help section, Lawn mower manuals.

My next project is a 1476 too, what's the state of yours? The 2.5bhp engine is probably a replacement, originally it was the 2bhp.

Osborne Tue, 13/08/2019

Thanks Henno, I found the manual for the 1476. I just collected it today and I hope it is in fine condition. The chains and sprockets look well serviced, correctly tensioned and not worn. There is no spark, of course! So I will have to clean points and check ignition, not sure yet what system it has. 

Engine turns freely, has good compression but is in need of a good service-

Cylinder looks really chunky and un-damaged so will have to decide whether to back lap to clean it up and see how it performs. I believe getting it out for a proper sharpen is quite a business and costly. 

Looking forward to hearing it come back to life

Osborne Wed, 14/08/2019

Hi Henno

i will try and attach some photos. The engine is I actually the 2hp not 2.5hp as I had been advised but the original recoil starter has been removed and replaced with a starter pulley with no guard, not great! So I am looking for a correct recoil starter for this if snyone has a spare. 

wristpin Wed, 14/08/2019

Strange about the starter.

We sold those machines when they were first introduced and despite the chunky looking cylinder they were always a problem keeping them in "set"; it was as if the relationship of the front of the bottom blade and the centre of the cylinder shaft was not quite right. Webb actually acknowledged that some users / dealers were experiencing issues and made one or two suggestions for overcoming them  - most of which were in effective but we found an in house solution which went a long way to achieving and maintaining a decent quality of cut. 

When regrinding the cylinder it is normal practice to reface the bottom blade at the same time  but instead of following the horizontal flat surface of the lipped bottom blade we ground in some relief  - that is to say we took a few thou extra off the back edge of the lip so that the rotating blades were not dragging across the full width of the lip but were giving a clean cut on the front edge. This worked well .

The other point to note is not to over tighten the bolts and nylok nuts on which the cylinder bearing carriers pivot - they were the chunky ones just above and to the rear of the front roller, either 17 or 19mm spanner size. The trick was to tighten the nuts and then back them off just enough that the the bolts could be rotated by finger pressure. This ensured that when using the adjusting screws to set the cylinder to the bottom blade the carrier could move smoothly and not "wind up" against the clamping force of over tightened pivot bolts.  

The only other particular issue with that machine, particularly if the owner did a lot of mowing without the grass box in place,  was a build up of grass under the blower housing (engine cowling), around the ignition coil and cooling fins, which if left unattended to could result in over heating and the possibility of a loose valve seat. 

Osborne Wed, 14/08/2019

Thanks Wristpin that’s very interesting about the setup. I am hoping to find an original recoil starter to sort that issue, the current fixture is somewhat agricultural! Any clues on the missing spark? I think it has an ignition module but have not removed fly wheel yet, will have to wait till the weekend.

The carburettor is a new one too fuelling direct from the tank. 

 

wristpin Wed, 14/08/2019

Have a look on the blower housing for the words Model, Type and Code and the corresponding numbers. The Code numbers will date the engine. If they start with say 85, that equates to 1985. The numbers will either be on the horizontal surface adjacent to the spark plug or on the vertical surface adjacent to the fuel tank. The tank and carburettor look to be correct for that engine.

If you remove the blower housing, three hex head screws, and post a decent image of the ignition coil it will determine whether it is “ electronic” or has points behind the flywheel . I think that it should be electronic. No need to remove the flywheel at this stage.

Osborne Wed, 14/08/2019

Yes it is

wristpin Wed, 14/08/2019

60102

6 cubic inch capacity

0 design series 0

1 horizontal crank and vacujet carb

0 plain bearing

2 rewind starter

Henno Thu, 15/08/2019

I believe someone cut the pulling mechanism /  starterkit right off using a grinding wheel or some other tool. This is one part with the blower housing. Finding a new one is a different matter. I saw one on ebay yesterday, it is in the USA.

https://www.ebay.co.uk/itm/Briggs-Stratton-2-hp-BLOWER-HOUSING-RECOIL-STARTER-ROPE-60102-1015-01/163742439877?hash=item261fcf59c5:g:LaUAAOSw6fVdCfYI

And a complete engine in the UK:

https://www.ebay.co.uk/itm/Briggs-and-Stratton-2hp-Engine/293177380335?hash=item4442bbcdef:g:eIAAAOSw901dRzor

Or somebody in the club has one lying around??

 

Henno Thu, 15/08/2019

@wristpin, that's brilliant, your explanation of the codes that make up the engine number! Is there a table of the codes? Maybe put a pdf on the site with the manuals?

wristpin Thu, 15/08/2019

On the smaller engines of that time rhe starter case was spot welded to the blower housing . Quite why  someone has hacked it off will remain a mystery. It shouldn’t be too difficult to pick up a replacement housing but remember that although it will fit  the Model Type and Code numbers may not match  which may case an issue later if used to order parts.

The info for interpreting the model numbers used to be ( may still be) shown in all the BS workshop manuals. This site does not allow pdfs but I will post an image of a page later.

hortimech Thu, 15/08/2019

[quote]

When regrinding the cylinder it is normal practice to reface the bottom blade at the same time  but instead of following the horizontal flat surface of the lipped bottom blade we ground in some relief  - that is to say we took a few thou extra off the back edge of the lip so that the rotating blades were not dragging across the full width of the lip but were giving a clean cut on the front edge. This worked well .

[/quote]

It should work quite well, because that is how you are supposed to grind all bottom blades, you always take metal from behind the leading edge first. It also explains why you insist that you have to relief grind cylinders if you want to backlap them later, something I rarely did, but I was involved in a lot of backlapping (golf club machinery) ;)

wristpin Thu, 15/08/2019

It should work quite well, because that is how you are supposed to grind all bottom blades, you always take metal from behind the leading edge first. It also explains why you insist that you have to relief grind cylinders if you want to backlap them later, something I rarely did, but I was involved in a lot of backlapping (golf club machinery) ;)

Perhaps I should have made it clear that the issue was that out of the factory Webb were grinding the bottom blades flat with no relief. Relief on cylinder blades is a different issue - it's to trap the paste for back lapping.

Another machine that seemed to defy all efforts to get them to set up to a decent standard were Dennis Paragons. We looked after two from different owners and never looked forward to their machine's visits for service, but fortunately the owners seemed quite happy with the result.

hortimech Thu, 15/08/2019

No, the relief on a cylinder blade isn't to trap the paste, it is to reduce the potential contact area, which is why you have to grind bottom blades with a negative angle, it gives you the cylinder to bottom blade version of hollow grinding used on shears & scissors.

I cannot say I had a problem with the Webbs, I just ground them, put them back together and they usually set up correctly. Now the earlier Webbs (the ones with the plastic handles), they were a pig to set up, the frames twisted if you breathed on them ;)

wristpin Thu, 15/08/2019

No disagreement re reducing the friction area but if you refer to Toro "university's"  reel mower theory it does make a point of saying that relief on the cylinder blade is needed for trapping the back lapping paste..

Reverting to the matter in hand, Webb were concerned with the complaints that they were receiving and their then Service Manager, a Mr Coffee, issued a service bulletin on the subject . I also suspect that they made a running change on the production line  - adding a bit more relief to the bottom blade. 

Osborne Thu, 15/08/2019

Thank you all for the really useful information. It has an ignition module, not points. I have polished up all contact surfaces but still no spark.

I am very interested in the discussion on the cylinder, it looks in good condition but i will clean it up and check cutting efficiency.

Still have to get the engine running though!

wristpin Fri, 16/08/2019

Remove the kill wire from the coil and try again. If there is still no spark you have a dud coil.

Osborne Fri, 16/08/2019

Thanks Wristpin i will do that test this evening. And thanks Henno for the two links, I have found a recoil mechanism at The Mower Centre so that is solved. 

Osborne Fri, 16/08/2019

Can anyone advise on the correct gap between the contacts between the coil and flywheel please. And is there a link anywhere for a service manual for the Briggs & Stratton 2hp engine and 5hp engine?

Thanks

wristpin Fri, 16/08/2019

Yes, there is a manual “ Single Cylinder L Head” ( built after 1981). Pt No 270962-12/03 . Will be ok for pre 81 with certain exceptions but you may be able to pick up an earlier version. There is also a BS Repaiman’s Handbook covering engines from 1919 - 1981. Pt No CE8069.

Ignition armature air gap, 10  - 14 thou. BS used to  / may still produce a plastic strip.

Method of setting. Turn flywheel magnets away from armature. Slacken both armature screws an pull it away from the flywheel. Tighten one screw. Turn the magnets to under the armature. Insert non magnetic gauge strip. Slacken the screw and allow the magnets to pull the armature down onto the gauge. Tighten both screws and turn the flywheel to eject the gauge.

hortimech Fri, 16/08/2019

Would it help if I told you that I worked on Toro machinery for over 25 years, went on numerous Service courses down at St Neots and have the grey jumper to prove it ?

So, yes, I know all about grinding reel mowers and backlapping.

Toro never recommended anything but spin grinding (others, such as John Deere, recommended relief grinding), but they did recommend backlapping as a maintenance procedure. I have taught numerous greenkeepers how and when to backlap, so I think I understand backlapping as good as anyone ;-)

wristpin Fri, 16/08/2019

Would it help if I told you that I worked on Toro machinery for over 25 years, went on numerous Service courses down at St Neots and have the grey jumper to prove it ?

So, yes, I know all about grinding reel mowers and backlapping.

Toro never recommended anything but spin grinding (others, such as John Deere, recommended relief grinding), but they did recommend backlapping as a maintenance procedure. I have taught numerous greenkeepers how and when to backlap, so I think I understand backlapping as good as anyone ;-)

 

Is it not strange  then that Toro have a section on back lapping and single blade relief relief grinding in the maintenance section  of their "university" notes on reel mower theory and use? 

I  think that we may have overstayed our welcome on this subject!

Osborne Sun, 18/08/2019

I was so wrong! I do have points ignition!! So will replace these and condenser and hope for spark. It’s great to learn! 

wristpin Sun, 18/08/2019

Quite possibly the points only need to be cleaned and then set to 20 thou. Also, check that the little fibre operating plunger is free to move. If you remove it, make sure that it goes back the right way around - the grooved end away from the crank .

If you buy genuine BS points they come with a little diagram showing the correct routing for the braided wire between the pivot block and the moving point arm - important. Also the genuine set includes a little plastic gizmo to aid compressing the spring that retains the wires.

 

 

Osborne Sun, 18/08/2019

Thank you Wristpin and all for the discussion and for the  detailed information.

I have ordered a new set of points and condenser as well as air filter and spark plug.

The cylinder and bottom blade do look in very good condition so when the engine is up and running I will see how the cut is. I have bought the two manuals you suggest and I hope they will cover the 24" ride on, the next job!