I have bought an old Rover Colt 8 Model No. 7347. It has been re powered with an 11.5 Hp Briggs and Straton. It seems to travel far to fast. The pulleys and gear box drive sprocket all look to be OK and original.
Welcome here, seems like nobody with Colts are going to chip in with any suggestions. It would have required some drastic modification to be able to alter the speed on one of these. I assume this is just a single speed forward/reverse gear?
Hello Fliped61 and Norm The Model 73 was the last of the colts - with Model 7313 (5hp), 7344 (8hp) and the 7347 (8hp elec start?)
My best guess is that in converting the machine to an over-powered 11hp, the primary pulley (on the 11hp engine) is too large.
If the travel speed is too high and the transmission sprockets look original, the first check would be with the engine drive pulley, not the chain trans after the gearbox output.
Hope this helps -------------------------------- Jack
Good call there, I'm just wondering if the pulley has been put on upside down, I assume it could be done, this would mean the cutter pulley would be driving the gearbox. This would mean that both belts must have been changed and I thought that would have raised the alarm bells as both belts would not be from the parts book
I'm just wondering if the pulley has been put on upside down, I assume it could be done, this would mean the cutter pulley would be driving the gearbox.
G'day Norm Maybe ... the schematic list seems to say that is possible. ['5' is the engine pulley]
My best guess, though, is that an 11hp unit complete with its pulley were swapped with the original unit.
An 11hp unit is not suited to the colts, and I suspect the little gearbox unit will fail quickly.
The pulley is the correct way up. I suppose it would be difficult to get another engine pulley? And if I could would it fit the 11.5 Hp engine? Thanks for you're help Norm and Jack
The shafts are all the one size, one inch diameter and the rev range will be similar so there is something fundamentally wrong.
Phil, Do not think about trying to find another pulley, you have to work out what is wrong. Are you sure the big end of the pulley is driving the cutter belt?
A few pictures may help, but there really isn't that much to these machines. How fast is too fast by you're impression? Most of these colts go sort of a brisk walking/jogging pace, to slow them was just to slip the belt like a clutch..
Just another thought, how fast is the engine revving?
Is the governor working or has it just been cranked up to rev hard, if so it needs fixing to be able to come back to idle when stationary, then you can work out the rev increase you need for cutter speed and travel.
I used it today and noticed yes it does rev hard with the throttle at about 3/4 open. If I cut the revs back the engine dies under load, and it wont run at a slow idle when stationary in nuetral