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Having had a disaster almost a year ago in my Spitfire because of excessive prop angles, I am now approaching the refit of my engine/box and prop in a few days.
I have ordered one of the volvo gearbox mounts as the current one is very wobbly. I read how Galileo did his (good article) but I am unsure if my engine is at the normal height.
So how much of an angle should the front section of the prop be at? (ideally compared the gearbox centreline)
Guidance very welcome!
There doesn't seem to be a maximum prop angle, nor can you actually ACHIEVE much of an angle without the engine sticking up through the bonnet! I don't know how far out your Spit angle was, but i'd have thought you'd need at least 15 degrees to do it harm. With the confines of the engine bay, I imagine you'd struggle to get as much as 5 degrees. So IMO, it's a non issue!
From what i've learned, the thing to avoid at all costs, is a ZERO angle between the the prop and 3rd motion shaft/O/D output shaft. This has been known to introduce vibration and unwanted sympathetic resonances in the driveline as well as shortening UJ life because it's always running in exactly the same line.
I'm not knocking Galileo, far from it, but I have fitted a good half dozen Volvo mounts now and have not bothered with a 6mm spacer nor have I had any problems! If it looks like you are close to the dreaded zero angle, use the Sprint method of mounting the centre bearing with one lug of the bearing housing BELOW the body mounted support bracket.
When I built the Carledo, I used the Vauxhall sourced front coupling, which resembles a small Rotoflex unit. After i'd done all the work fitting the engine and gearbox and supplied the prop and front section of the Carlton prop for my man at Proptech to assemble and balance, when he handed it back to me, he commented that THIS sort of coupling should run the shaft at no MORE than 1 degree out from the gearbox/crank line. NOW HE TELLS ME! So I took it home and fitted it with some trepidation, but it LOOKED pretty close so I went with it! Either i'm very lucky or VERY VERY good, cos it's still there 8 years and countless storming starts later! And though I have 2 spare couplings, so far i've not needed one!
Steve