Hi all, I am rebuilding my engine with a Phoenix crank and have a slight problem. The crankshaft pinion is tight on the crankshaft. Is this normal or do you need a different pinion for the Phoenix crank. Also the crankshaft key for the pinion is also tight does this also differ for the Phoenix crank.
Whilst on the subject of keys does the flywheel key differ on the Phoenix crank

Yours John Mason

Location: Mansfield Nottinghamshire

I've just tried three crankshaft gears on a new Phoenix crank and all three fitted without being tight. They weren't loose either though. I'd check your gear for any slight burr and clean up the internal face very carefully and try again. As for the keys, I've always used the standard ones available from the various suppliers and can't recall any real issues with fit although I might have done a bit of fettling which is to be expected.

If you aren't confident in what you're doing, take Malcolm's advice, below.

Steve

Location: North Yorkshire

I've never had a problem with gear fitting, but like Steve says you need to make sure that there are no burrs or other damage. What you do need to be aware of is that sometimes the keyway is machined for a smaller diameter key - not a problem as long as you know about it, and I've had some cranks where the flywheel nut is not the standard thread- again not a problem, but if the nut is tight, that might be why. Usually you have to take a few thou off the side of the key to get a good fit.

I would recommend that you have the crank fitted to your crankcase by someone who has previous experience. New cranks and bearings are expensive things and the last thing you want is to face stripping the engine down once it is finished.
I have been playing with Austin 7's for 40 years but recently had my Phoenix crank fitted by an expert, the cost was almost negligible when you look at the cost of the parts and the potential damage if it isn't right.

Thank you all for the advice. I have built up an engine previously when I had to use a replacement crankcase and that was successful with no problems. On this occasion it all went together with no tightness just a nice fit. Having taken your advice I have ordered new woodruff keys (wether I need them or not as the cost is nothing) and I have rubbed the inside of the pinion with emery cloth. It now fits freely but not sloppy.. Once again thanks for the advice.

Location: Mansfield Nottinghamshire

I did this job a couple of weeks ago. The crankshaft gear was a light interference fit, ie needed very gently tapping home with a rubber mallet. The key I had wouldn't fit, so I ordered a new one, which also didn't fit! I had to take a few thou off the side of the key on an oil stone to make it a nice snug fit . Everything all went together beautifully then. obviously the key has to be fitted before the gear is fitted...

Oh, yes the nut on the rear of the crank wasn't a standard A7 one, must use the one supplied with the crankshaft.

Stuart.

I've been rebuilding an engine in the last few days (standard crankshaft), and I had to take a few thou off the side of the (new)key, so it could be a batch of slightly oversize keys.

Location: Bonnie Galloway

I have always 'fitted' keys, I assumed it was common practice to adjust them to a nice snug fit.

David Cochrane explained to me about the rear crankshaft nut.
The standard thread would be one of Austin's 'Admiralty' threads and David specifies that for shafts he buys.
However Phoenix tend to use standard Whitworth by default in which case the Phoenix nut is needed.

Location: Melrose, Scottish Borders

No, it's normal for keys such as these to be specified to the same size as the keyway and therefore needing a small degree of 'fitting'. The alternative is the risk of the key being a touch undersize and that would be no good at all would it? Remember, the manufacturer of the keys is not likely to be the manufacturer of the keyway.

Steve

Location: North Yorkshire

Yes quite right Steve and R. I wasn't very clear. The key I had "in stock" came from one of Fathers tins of keys, so I wasn't certain it was the correct one, hence I ordered one. They are far better ground to size, so they fit properly.

Thanks again for the advice. Yes I have the correct nut and lock washer supplied with the Phoenix crank. I do however take on board the trimming of the key to fit the new crank. The previous strip down and rebuild I did on a seven engine used the same crank and key etc so all went together without having to make the key fit.

Location: Mansfield Nottinghamshire