Wacker Plate Engine Mountings

[malcolm]

I bought a wacker plate this morning for really cheap. It works but the engine shakes backwards and forwards like mad in use which isn't surprising as it is only supported by 4 horizontal bobbin mounts at the sides.

Anyone have a wacker plate? How is the engine supported? I would have expected to see some sort of damper mount in there somewhere. Otherwise maybe my running speed might be wrong or engine mounts knackered if the engine is being set off by the vibration.

 

[GW8IZR]

Mine has the engine mounted directly to a heavy plate, that is suspended from the plate that sits on the ground by four rubber mounts much like big engine mounts, the drive to the offset rotating drum that makes the vibration is mounted solidly to the ground plate and the difference between the two plates is taken up in the belt drive.

HTH

 

[GW8IZR]

Pics needed - there's a couple of 'systems'...

you want pics, come and take them :-) its bleak out in that shed..

I'll venture out in daylight and snap some of mine tomorrow

 

[malcolm]

Thanks, will post pics in the morning. I've not really had a good look at the thing yet.

 

[malcolm]

I've had a better look and the engine mounting rubber near the belt drive to the rotator is broken. That'll explain it.

I've attached a couple of photos anyway. There are 4 bobbin mounts horizontally between the plate and the engine. The other bobbin mounts further up are just vibration suppression for the handle. Anyone fancy guessing at the make? There are no markings. It has a Robin engine apparently and will be a good 20 years old.

 

[Bill Edwards]

Can't help on the make, but if my Robin engine is anything to go by yours will never take more than a second pull to start, will never miss a beat and at twenty years old isn't even half way through it's life...
Cracking engines.

 

[malcolm]

It does start first time. It seems quite a well engineered piece of kit. The anti-vibration rests for the handles turned out to be the same as the engine mountings so I've swapped one over. The engine doesn't shake any more and it self propels properly now. Just need to find something to whack now.

 

[the snooper]

It does start first time. It seems quite a well engineered piece of kit. The anti-vibration rests for the handles turned out to be the same as the engine mountings so I've swapped one over. The engine doesn't shake any more and it self propels properly now. Just need to find something to whack now.

Walk into a tool hire shop with the broken mount they may keep some in stock

 

[malcolm]

I should be OK for mountings as the rest look OK and I'll not be putting the thing through a lot of use. I thought about replacing the lot but four 50mm x 50mm bobbins with female threads both ends work out at £28!

I've ordered a belt though for more than £2. There is some writing cast into the belt cover that says to use an A28 belt. There is an A27 on there at the moment presumably to compensate for the failed mounting, but it is too tight now the mount is fixed.

 

[the snooper]

I have trench wackier, 2 stroke and it's a pain to start I've put a carb kit on it I think next will be crank seals and maybe a set of rings

 

[malcolm]

The engine and vibrator both seem to secure to tapped holes with no adjustment. I think the belt adjustment is a split pulley. I'll find out when I try to fit the new belt.

I had a 2 strove strimmer once - awful thing would never start and I left it behind when I moved.

 

[the snooper]

The engine and vibrator both seem to secure to tapped holes with no adjustment. I think the belt adjustment is a split pulley. I'll find out when I try to fit the new belt.

I had a 2 strove strimmer once - awful thing would never start and I left it behind when I moved.

I have a 2 stroke strimmer no make on it, it's quite old and my guess is its a Robin it starts up way better then the diposible cheap things you can buy now

 

[roofman]

Ive got the same machine and had the same problem with vibration...i went to the local car breakers yard and sorced some rubber mountings off a cars subframe and welded them on,all good since with almost zero vibes. Can take a few pics iff your intrested to see

 

[Robotstar5]

Maybe cardiffrob can make you some new mounts?

 

[malcolm]

Ive got the same machine and had the same problem with vibration...i went to the local car breakers yard and sorced some rubber mountings off a cars subframe and welded them on,all good since with almost zero vibes. Can take a few pics iff your intrested to see

It would be good to see photos. Do you have any idea of the model or age of the things? A cast aluminium belt cover must mean they are quite aged unless someone got carried away designing the things.

 

[roofman]

It would be good to see photos. Do you have any idea of the model or age of the things? A cast aluminium belt cover must mean they are quite aged unless someone got carried away designing the things.

will upload some tomorrow Malcolm

 

[malcolm]

Either the engine or the vibrator should be on slotted holes to adjust belt tension.
Of course, if you've seen that and got it at the end of the slots at the 'loose' end, ignore me

You were quite right - turned out that the engine mounting bolts adjust the belt tension.

The machine turns out to be an MBW. Quite an old one but a reasonable spec when it was new. I think the belt tension provides some fore-aft damping and needs to be a fair bit tighter than a car fan belt. Engine didn't knock about when the tension was unreasonably tight and it self powered forwards better. Maybe the engine speed is wrong - the carb needs a clean. I think I will invest in new mounts as I can use the old ones to isolate the handle to prevent vibration white arm.

I did my first bit of wacking today but had to pull the machine around a bit.

 

[malcolm]

Fixed it (hopefully) by fitting a complete set of 4 engine mounts and 4 handle mounts and the new belt. On a short test the engine didn't vibrate nearly so much and the handle is much more comfortable, but it still doesn't walk very well.

If anyone else ever needs mounts for this sort of thing I found www.specialisedtools.co.uk supply them for a decent price. Everyone else wanted £7 each and I got them for about £1.60 each.