What's that sound?
Thread Starter
Instructor
Joined: May 2018
Posts: 200
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From: Tennessee
What's that sound?
Sbc 350. What could this sound be? I don't know about the mileage of this motor and next summer I plan to rebuild it and upgrade it (vortec heads and all that). The car shakes and awful lot and this sound doesn't increase as rpms do. Motor mounts?
Pro
Joined: May 2016
Posts: 708
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From: Minnesota
Doesn’t sound steady enough for bearings, but could be. Maybe broken rocker(s) or pulled out rocker studs? Broken valve spring(s)? The shake is probably due to a miss.
I would start by pulling the valve covers and looking things over. Go from there.
But - it does NOT increase with rpm?
if you suspect motor mount, have another person get in the car, put in gear and lean on the gas (like the start of a Brake-stand) while you watch the motor with the hood open. If it moves a lot, you may be right about mount(s). The DS usually goes first.
I would start by pulling the valve covers and looking things over. Go from there.
But - it does NOT increase with rpm?
if you suspect motor mount, have another person get in the car, put in gear and lean on the gas (like the start of a Brake-stand) while you watch the motor with the hood open. If it moves a lot, you may be right about mount(s). The DS usually goes first.
Last edited by JoeMinnesota; Jun 25, 2019 at 11:49 AM.
Thread Starter
Instructor
Joined: May 2018
Posts: 200
Likes: 25
From: Tennessee
I will try leaning on the gas tonight, thank you for the suggestion. Doesn't increase with rpm, but its louder when you first tap the gas, then that's it. I did install a new fuel pump, it's running very rich and bogs way bad when you floor it.
Thread Starter
Instructor
Joined: May 2018
Posts: 200
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From: Tennessee
also also, the car does pull hard to the right. The motor mounts are the last things to be untouched. New trans bushings, diff, a arms, all that. But it could just be an alignment issue, haven't had a chance to get it aligned
Last edited by BlueL82; Jun 25, 2019 at 12:27 PM.
Racer
Joined: Mar 2019
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From: west mi. / ms. gulf coast
I have had motor mounts completely come apart with no noise whats so ever. Pulling is either alignment , brakes or tires. As stated pull valve covers and check for broken spring, rocker assembly , that would cause a miss. as aquaroscoe stated above check the torque converter bolts. and bolts to the fly wheel/crank. It is odd that the noise doesn't increase with acceleration of the engine. What did you have done recently?
Pro
Joined: May 2016
Posts: 708
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From: Minnesota
If you just changed the fuel pump, mechanical on the block or electric? If mechanical maybe pull those bolts loose and make sure your pump pushrod is in position and working proper. Did you put a bolt in the block to hold the rod in place? Was it removed after install? Although it probably wouldn’t run without that working and it would change with rpm.
Thread Starter
Instructor
Joined: May 2018
Posts: 200
Likes: 25
From: Tennessee
The fuel pump was installed correctly, this noise happened before I changed the pump. I think I might need to start setting money aside to swap out this motor and put more power into it. You know, while I'm at it.
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Thread Starter
Instructor
Joined: May 2018
Posts: 200
Likes: 25
From: Tennessee
Does this look normal? I really don’t know much about valves and rockets but see on the left how that washer/retainer on the spring is sitting certain and flush? The one on the right almost looks like it’s sitting on top of where it needs to be.
