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| | | | Joined: Nov 2018 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2018 Posts: 44 | Friends:
My 235 sings a constant musical note while running, when idling and running down the road. It is the same kind of sound you get wetting your finger and rubbing it around the rim of a glass. It is continuous and the tone and intensity stays the same regardless of engine speed. ! What is the cause? It is difficult to isolate to a specific part of the engine but seems louder on the distributor side. The only thing I can guess is the lip seal on the timing gear cover. I have no oil leaks.
Regards,
Joe
'49 3100 "Sweet Caroline" because the truck has fabulous curves .... like Caroline!
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Take the fan belt off & try it. If it goes away then spin the water pump & Gen. by hand & see if makes a noise or turns hard.
Check the dist points to see if there is a small amount of grease on the cam. I've seen this make a squeal when the rubbing block on the points are dry.
George
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Nov 2018 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2018 Posts: 44 | George,
Thank you for the reply. The distributor points were lubed recently. When I installed the water pump, it did not turn freely in the sense of spinning but otherwise exhibited no excessive play. I attributed the stiffness while turning to the seal which would normally be lubricated by the coolant. I had the generator apart and the bearings were lubed and fine.
Joe
'49 3100 "Sweet Caroline" because the truck has fabulous curves .... like Caroline!
| | | | | Joined: Aug 2012 Posts: 1,214 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 1,214 | If it weren't for it staying constant and not varying with rpm I'd say air rushing through the air cleaner or a vacuum leak around the carb, intake or even the vacuum wiper motor under your dash (if so equipped).
But it's loudest on the dist side, hummm, maybe a leaky vacuum advance canister?
I've seen electrical circuits vibrate at frequency's that could be heard, if you had a radio and heard it the capacitor/condenser in the dist could cause that. Might try replacing the condenser just for GP.
Good luck
Dave
| | | | | Joined: Nov 2018 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2018 Posts: 44 | Thank you Volfandt, I DO have the air cleaner off. I will check it with it on and the vacuum advance, the truck's performance is as if it were not working.
'49 3100 "Sweet Caroline" because the truck has fabulous curves .... like Caroline!
| | | | | Joined: Mar 2014 Posts: 4,484 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,484 | I've seen this with a failing vac advance diaphragm. Same thing with air pressure regulators for compressors. Sounds like a tuning fork, doesn't it?
~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
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