Joined: Dec 2017 Posts: 2 Threads: 1
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Hi ,
I have been experiencing a high pitch noise from my 1936 Austin 7 Special, running on early 30s parts.
The car has been fitted with a electronic 6V SU fuel pump, I suspect this is the source of the noise.
My motor repair shop has replace the bearing on the distributor, that solve the problem for few weeks, it seems, but now I get the noise again.
We checked and confirmed fan pulley was ok, and not the source of the noise.
Apart from the noise, the cars runs well, starts well, brakes well, no overheating.
I just do not want to run the car till something breaks apart, so if I can trace and rectify the source of the noise, I would like to get it sorted out.
Appreciate your valuable feedback.
Melvin
Singapore
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Location: Darkest Bedfordshire
30-12-2017, 09:43 AM
(This post was last modified: 30-12-2017, 09:54 AM by Chris KC.)
Did they disturb the gasket between dynamo and housing by any chance?
Sorry, pressed wrong button! Dynamo gears will make a high-pitched whine if you reduce gasket thickness. But it wouldn't be intermittent. I've run SU fuel pumps for years and never heard a high pitched noise from them - they just tick gently when you turn the ignition on.
If disturbing the distributor made it go quiet even temporarily I'd suspect something in that area...
Joined: Aug 2017 Posts: 1,713 Threads: 47
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Location: Auckland NZ
Car type: 36 Nippy, 31 RM, 38 Special, 24 Works Rep
An intake manifold air leak can cause a high pitched whistle, although if work on the distributor/dynamo initially fixed it and now its come back just the same, one would have to suspect the dynamo has an issue.
Black Art Enthusiast
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I once traced a mystery noise to a small piece of brake lining which had broken off and got lodged between lining and drum. Might be worth a look?
Charles.
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30-12-2017, 11:30 AM
(This post was last modified: 30-12-2017, 03:00 PM by Ruairidh Dunford.)
As already noted - leaky gaskets squeak (exhaust, head, inlet and carb - cover with damp cloth or thin oil to find which).
Top fan pulleys, clutch release bearings and fan belts too.
Is the noise related to engine speed or wheel speed?
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I would check the dynamo. Remove the little circular oil cover (it prises out with a small screwdriver) and drip a couple of drops of thin oil down.
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A dry distributor cam can also squeal. A smear of vaseline cures it.
Jim
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Location: Deepest Frogland 30960
Car type: 1933 RP Standard Saloon
I agree - dynamo end bearing/bush.
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Ah OK, I only know the electric type. Still suspect the dynamo rather than the fuel pump though.
