OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Reel-Type Mowers Scott Bonnar twin rail repairs

Hi Guys

I know this topic has been done to death a little but my question is a bit left of centre.
Ive recently picked up an SB 45 20" and im %99.9 sure there are no cracks in the rails.
I plan to refurbish it at some stage but my question is if i do decide to strip it down should i get the rails strengthened whilst its apart or am i better off
leaving it alone ?

regards
Peter G

Hi Peter,

I totally understand your concerns in regards to this matter. The 20 inch Series 2 frame was the most feeble of the 3 variants available at the time.

As far as an answer to your question it's all going to depend on what engine you intend to use on it. If you are fitting a new generation Briggs unit then it would be ok as it is, but if you intend to stay with an original style Briggs power plant then a strengthening process is a must.

Personally I wouldn't consider any of the older engines on this particular size machine.

Regardless of what I've suggested above, strengthening is a pro-active thing to do on these limited life chassis' which they definitely were from day one.

Cheers,
BB.

Thanks for the reply BB

It has already had a new B&S fitted but although I haven’t detected any cracks it’s possible they may be hiding under the paintwork, in addition to that I have since noticed a slight bow in the rear rail.
I think the decision has been made for me this time 🤔

I am tempted to do the strengthening work myself but I have read that twisting in the frame is a real concern through the welding process.
Any words of wisdom from any experienced campaigners would be greatly appreciate 😁

Thanks..

Hi Peter,

Yes I also have a 20 inch twin railer here myself and that has the slightly bowed rear rail symptom as well.

Eventually I will pull this one down and do a full rebuild on it and have a new generation Briggs fitted.

Don't be at all surprised that yours has got some stress fractures lurking underneath the paint finish from years of single piston thumping. Those early engines were very poorly balanced and passed all that force into the chassis which is only made up from pressed sheetmetal.

Cheers,
BB.