Albert, that engine obviously has some adaptations to make it more fluid-proof, and also less prone to setting fire to the oil it is pumping, and that may be the reason I don't recognise it. Because it is labelled as 3.5 hp, it may be one of the 9 cubic inch models but it could also be larger than that. Because you can't find any numbers stamped on the cowl, I think we need help from someone more familiar with specialised pump engines.
Can anyone help? AVB?
Post-Edit: Because that engine is heavily modified from the Briggs & Stratton design, presumably to make it safe and lawful to use it to pump flammable substances, this is a rare situation where in my opinion we cannot help you with advice on dismantling or re-assembling it. Of course if you can give us the manufacturer's numbers we will help with identification, but not with repair or maintenance advice.
Last edited by grumpy; 12/08/15 06:35 PM. Reason: Add Post Edit
