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I have got a potential spare engine which might be useable, but it's three bearing.
Is it feasible using something on a 1929 chassis just because its there, or would the differences in crankcase height muck up the uncoupled handbrake mechanism, entail drilling new chassis holes or whatever?
The front starter wouldn't be a huge problem.
Be interested to know from someone who has done the same.
Was also thinking of the drivetrain height issue for people who run solid mount engines on rubber for safety... presumably that raises the engine a tad under 1/2" or so?
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I'm running a 3-brg engine (+ 4 speed box) in a '31 chassis if that helps Jon (albeit with coupled brakes).
But I'll hazard most people would say why not just look for a 2-brg engine...
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well I know it's possible then! I agree, seems silly, but it landed in my lap and it seems that it was recently rebuilt and just has something like a loose nut seizing somewhere. I was going to use it to continue my reverse-meccano learning and if it really is all fine and dandy, seems silly to put aside when my '29 will plainly need some attention at some time.
Just for the purposes of a question on the forum, do the feet 'oles have the same position and any idea about the difference in height of output shaft. Or does one not notice?
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Yes, that! I think it's 3/4" isn't it? (sorry, can't read the tape on my mobile). Hence the different types of fan pulley.
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Brilliant thankyou - incredibly useful.
so which is the datum hole - are the front holes always the same and one redrills the rear? Just trying to get my head around why the pulleys will be different as presumably the crankcases are the same length.
Or did the units historically come forward to make up for longer 4 speed box?
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01-05-2019, 09:40 AM
(This post was last modified: 01-05-2019, 10:16 AM by Chris KC.)
Yes, that.
Jon, it's not a big deal to fit a later engine into an earlier chassis, if that's what you want to do; but as you have surmised there are a few snags to overcome. I honestly can't give you a blow-by-blow as mine was done decades ago, and by someone else at that, and even then on a car which was being built around the engine. However if your intention is merely to use the 3-brg as a spare or temporary replacement, these sound to me like problems you could live without. Would it not be a better idea to acquire a spare engine which is directly interchangeable with the one you have? Then in times of need it is a simple matter to exchange the two.
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Car type: '28 GE Cup. '28 AD Chummy '30 RL Saloon. '34 RP Saloon. Too Many toys!
Jon, the dimentions of the holes vs each other are exactly the same.
Effectivley the 'engine' is moved 3/4 inch forward vs the hole positions in the chassis. done by moving the engine mounts on the crankcase.
Note how in the photos the engine mounts are further back on the crankcase.
This was done initially because of the longer 4 speed gearbox (introduced in 1932?). You cant put a 4 speed box on a early coil crankcase as it hits the front cross member. That is unless you drill some new engine mounting holes.
Most 3 bearing crankcases are mounted so the crank is at a different angle vs the chassis to suit the low chassis driveline. Hence the different offsets on the mounts vertically in the pictures.
4 speed cars have shorter top fan pulleys, and a shorter nosecone also. as the 'engine' is nearer the radiator
The 3 bearing will go in, and bolt to your existing mounting holes, but the rear will be a bit higher than the proper engine, which could cause issues with the bulkhead, and if you put your 3 speed box back on you may need a longer propshaft. You will need the shorter fan pulley, but you may get away with using your existing nosecone.
The 2 bearing low chassis crankcase in my daughters box saloon is propped up at the front to help, but the flexible coupling still occasionally hits the tunnel.
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ok understood.
I've presently just found a bit of piston ring as being one of the things which might be causing it to lock up, so yes, it might be moving from the "sustainable re-using what you have" towards "problems I can live without" depending on what damage is in there.
Presumably the design of the casting feet for rubber mounting means it would be unwise NOT to rubber-mount just to help get the correct line if you did such an operation.
