Tool to remove husqvarna 61 cylinder bolts

[pp9]

I am trying to remove the 4 cylinder bolts, hexagon M4 is too small and M5 is little too big, see photos with M4 and M5 tool. What tool to use?

Thanks, Paul

 

[REJ2]

4.5mm seems worth a shot, they do exist according to google

 

[Tomos770]

Or just pinch off/file its corner.....then unscrew it with a punch (screwdriver + McHammer)

 

[Tomos770]

Or make a notch in the middle + screwdriver...

 

[idiotwithasaw]

It's probably standard 3/16 I believe but I don't have mine in front of me right now to confirm that.

 

[ammoaddict]

It's probably standard 3/16 I believe but I don't have mine in front of me right now to confirm that.

Pretty sure the older ones are 3/16" a 4.5mm may work though.

 

[Huskvarna hotellgäst]

They're definitely 3/16". These bolts are not metric.

 

[Bob Hedgecutter]

Never quite as complicated or over engineered as their German counterparts- but there is still some humour among Swedish design teams in a country that was well embraced in the metric system- a whole lot of the hex drive cap screws holding down this era of Husqvarna are indeed imperial driver ones and yes- they are 3/16- slightly larger than 4.5mm and slightly smaller than 5.0mm.

 

[NSEric]

The older 61's have coarse thread allen head bolts that take a 3/16 allen wrench holding the cylinder down.
I rebuilt one recently.

 

[huskihl]

61-272, 288, 395, 3120 all use sae cylinder base bolts

 

[Agrarian]

I am trying to remove the 4 cylinder bolts, hexagon M4 is too small and M5 is little too big, see photos with M4 and M5 tool. What tool to use?

Thanks, PaulView attachment 1075610View attachment 1075611View attachment 1075612

The 272 family use 1/4-20 Allen caps - go figure.

 

[Scandy14]

It’s the 3/16” yellow T-handled Whia in my set of tools. Some muffler bolts are also 3/16”.

 

[Huskvarna hotellgäst]

Never quite as complicated or over engineered as their German counterparts- but there is still some humour among Swedish design teams in a country that was well embraced in the metric system- a whole lot of the hex drive cap screws holding down this era of Husqvarna are indeed imperial driver ones and yes- they are 3/16- slightly larger than 4.5mm and slightly smaller than 5.0mm.

Nicely put Bob. I remember a Stihl rep at an Orange Field Day in NSW in the mid 80s being astounded to discover there were only 8 parts in a Husqvarna chainbrake when the equivalent Stihl model had about 20.

The SAE bolt story told to me went like this.
The 260CD and 480CD had slots machined into the sides of the crankcase into which was inserted an M4 hex nut and a circular spring clip to hold it in place. As well, a flat washer was fitted under the head of each M4 retaining bolt.
Now, an unhealthy number of these circular clips and washers were finding their way into the crankcase during saw assembly, so alongside the target to reduce the number of parts overall for the new 162SE that was being developed, was added a particular emphasis on eliminating washers altogether and the circular clips.
After some consideration of how this might be achieved, I'm told one person said something like, "S**t. Why don't we just use a course thread SAE bolt?". (I've translated from Swedish)

 

[nedsim]

Never quite as complicated or over engineered as their German counterparts- but there is still some humour among Swedish design teams in a country that was well embraced in the metric system- a whole lot of the hex drive cap screws holding down this era of Husqvarna are indeed imperial driver ones and yes- they are 3/16- slightly larger than 4.5mm and slightly smaller than 5.0mm.

In the late 70's I owned a '65(?) Volvo 122s. Lots of SAE fasteners on that car outside the engine. Some due to the American components -- Borg-Warner transmission, Bendix brakes, etc. But most of the suspension was also Imperial. Got to verify that when I had to change the rear end lying on my back in a sand pit in the back of a NJ junkyard.

Especially ironic considering that Volvo started as a division of SKF. Ball bearings have been metric since dirt was new.

 

[HarleyT]

Are you sure that it isn't a torx?

 

[Bob Hedgecutter]

Are you sure that it isn't a torx?View attachment 1076101

Isnt that how you make T27 fasteners?
Start with a 3/16 hex, see a 4mm key wont catch, try a 5mm hex and belt it a few times with a steel hammer when it wont go in- add some sludge and crud for good measure?

 

[Cantdog]

Isnt that how you make T27 fasteners?
Start with a 3/16 hex, see a 4mm key wont catch, try a 5mm hex and belt it a few times with a steel hammer when it wont go in- add some sludge and crud for good measure?

That explains it.......always wondered how/why they came up the with T-27 size....

 

[idiotwithasaw]

I'll be honest I've been using a 3/16 t handle for a little while thinking it was a 5mm and using it to take 5mm bolts loose on mufflers and the like, it wasn't until I grabbed what I knew was a 5mm hex bit to put in my driver to take something loose and noticed it didn't fit when the t handle did I was confused to say the least

 

[Bob Hedgecutter]

I'll be honest I've been using a 3/16 t handle for a little while thinking it was a 5mm and using it to take 5mm bolts loose on mufflers and the like, it wasn't until I grabbed what I knew was a 5mm hex bit to put in my driver to take something loose and noticed it didn't fit when the t handle did I was confused to say the least

I use mainly metric, we use the metric system here, but when I was younger there was still lots of American and British equipment around, so I grew up using all kinds of tooling.
My metric T handles are a different shape and brand to my Imperial ones- saves a lot of confusion and searching hex shafts for tiny stamped verification of sizes!