Check your PCV valve, hose, and connections, also to see if something is rubbing or squeaking on the underside of the air cleaner or carb.
Squeak from engine bay
Dear all,
My 1966 has an annoying squeak coming from the engine bay. Sounds like a typical worn out V-belt, but it's not that. I've replaced it and I ran my car without V-belt to verify it's not that. The issue remained.
The squeaking sound increases with RPMs and seems to come from either the back of the engine or the bellhousing.
I've replaced the clutch (incl. pilot bearing, throw-out bearing, etc.) about 500 miles ago and never had this sound until now. Also, the squeak remains the same when depressing the clutch pedal.
My local shop and I think it's more likely to come from the back of the engine (perhaps a leaking intake) but spraying with brake cleaner didn't change anything in the way the engine ran. We've listened with a stethoscope, and our first bet would be the back of the engine (a valve?).
Somehow the squeak only starts when the car is warmed up.
We're now running out of options, but I don't want to be sent home with this squeak still there.
Here's a video:
Any suggestions would be appreciated.
My 1966 has an annoying squeak coming from the engine bay. Sounds like a typical worn out V-belt, but it's not that. I've replaced it and I ran my car without V-belt to verify it's not that. The issue remained.
The squeaking sound increases with RPMs and seems to come from either the back of the engine or the bellhousing.
I've replaced the clutch (incl. pilot bearing, throw-out bearing, etc.) about 500 miles ago and never had this sound until now. Also, the squeak remains the same when depressing the clutch pedal.
My local shop and I think it's more likely to come from the back of the engine (perhaps a leaking intake) but spraying with brake cleaner didn't change anything in the way the engine ran. We've listened with a stethoscope, and our first bet would be the back of the engine (a valve?).
Somehow the squeak only starts when the car is warmed up.
We're now running out of options, but I don't want to be sent home with this squeak still there.
Here's a video:
Any suggestions would be appreciated.
1 - 20 of 24 Posts
Sounds like the noise is coming from the front of the engine. Fuel pump cam?
I don't think so, it's most likely coming from the back, closer to the firewall/bellhouse. We've tried to localize it with a stethoscope and it might be coming from the block/intake.Sounds like the noise is coming from the front of the engine. Fuel pump cam?
Weird, but for me, it sounded like maybe an exhaust leak tweet
Thank you for this suggestion. This is what the shop did today, but nothing weird to be seen and no increase in volume of the squeaking noise.Run it with the rockers covers off. Get some cheapies and cut the tops off.
I do on mine. Might help.
View attachment 896778
They have also switched from full manifold vacuum back to ported and checked the PCV valve/hose. Didn't help either. Same for the carburetor to intake gasket. The exhaust gaskets/headers were inspected but it's unlikely to be issue. It sounds more like some metals slightly rubbing against each other, or some air/vacuum leak.
Next step is replacing the intake manifold gaskets as the sound does seem to be a bit louder on the top of the engine, closer to the back. If this doesn't fix it, I will ask them to pull the transmission and check the clutch/flywheel assembly, as I've replaced these (for the first time) about 400-500 miles ago*.
(* I did replace the pilot bearing and throw-out bearings too. This squeak wasn't there since the clutch repair 400-500 miles ago, and the squeak remains regardless of depressing the clutch pedal or not.)
The weird thing is that after firing up the engine, the squeak only starts after about 30-60 seconds.
I will keep you all updated.
Towards the beginning it sounded like it was rpm related. If so it’s more than likely rotational. It also sounded the loudest on the passenger side. Easy to say from here but it’s hard to believe its not easily diagnosed?
Just doesn’t sound like anything to do with PCV or manifold/gaskets. I would be thinking flywheel, inspection plate, starter contact,,,? Definitely sounds metallic from here.
Good luck.
Just doesn’t sound like anything to do with PCV or manifold/gaskets. I would be thinking flywheel, inspection plate, starter contact,,,? Definitely sounds metallic from here.
Good luck.
Yes it does seem to be slightly louder on the passenger side. And it’s related to RPMs indeed. But my shop, who only do vintage Mustangs (!), still couldn’t find the issue. The inspection plate was checked on their car lift and slightly opening it with a screwdriver didn’t change the sound of the squeak.Towards the beginning it sounded like it was rpm related. If so it’s more than likely rotational. It also sounded the loudest on the passenger side. Easy to say from here but it’s hard to believe its not easily diagnosed?
Just doesn’t sound like anything to do with PCV or manifold/gaskets. I would be thinking flywheel, inspection plate, starter contact,,,? Definitely sounds metallic from here.
Good luck.
It’s just strange that it only starts after 30-60 secs when hot and only after a minute or two when cold.
Tomorrow the guys at the shop will continue by replacing the intake manifold gaskets and sealant. Spraying brake cleaner didn’t show a sign of a leak, but the stethoscope did point out a louder noise from the top and back of the engine near the intake.
Next step would be pulling the transmission to check flywheel, bearings, etc. but I’m hoping for a leaking intake.
Next step would be pulling the transmission to check flywheel, bearings, etc. but I’m hoping for a leaking intake.
Is it that "ticking" sound? I think that's an exhaust leak - maybe at the manifold-head interface or at the joint between the head pipe and the manifold
No it's that very high tone, that sounds like a singing bird or the sound of a cricket.Is it that "ticking" sound? I think that's an exhaust leak - maybe at the manifold-head interface or at the joint between the head pipe and the manifold
Local vintage car shop as well as another local Mustang shop are not thinking it's the exhaust, but who knows...
Intake gaskets have been replaced today. Another test drive tomorrow.
Going out on a limb here, but I would check the starter. Maybe the motor winding are going and its not disconnecting all the way possibly?
Troy
Troy
So it wasn’t the intake gaskets either…
A never ending story it seems and my money going down the drain!
A never ending story it seems and my money going down the drain!
Did you verify it was not the PCV system? Is it possible that it is an exhaust pulse squeaking through a choke air tube? Is something getting hot once the engine has warmed up and squeaking a little with engine vibrations such as exhaust against something, transmission or accelerator linkage? Is the blower motor on?
To me from here on my lazyboy chair,,😜 it definitely sounds metallic and it’s affected by rpm. So I would be thinking either a chirp from vibration or contact on a rotating assembly. The fact it starts several minutes after engine start is peculiar if thinking exhaust leak, as they tend to decrease as things heat up...
Have you tried pulling all the belts? Eliminates pulleys, bearings, and belts?
We’ve checked PCV and exhaust. Not that unfortunately. Blower motor was off.Did you verify it was not the PCV system? Is it possible that it is an exhaust pulse squeaking through a choke air tube? Is something getting hot once the engine has warmed up and squeaking a little with engine vibrations such as exhaust against something, transmission or accelerator linkage? Is the blower motor on?
Yes, still there when running without the belt.Have you tried pulling all the belts? Eliminates pulleys, bearings, and belts?
I agree that it sounds metallic and is RPM affected.To me from here on my lazyboy chair,,😜 it definitely sounds metallic and it’s affected by rpm. So I would be thinking either a chirp from vibration or contact on a rotating assembly. The fact it starts several minutes after engine start is peculiar if thinking exhaust leak, as they tend to decrease as things heat up...
They have pulled the transmission today and the bellhouse and flywheel.
Here’s a new video of the engine running without transmission:
They have reinstalled the flywheel, clutch, etc. but still there.
Running out of options now and they start to think it could be coming from inside the engine? Hard to believe as the engine runs great, looks fine and doesn’t consume any engine oil at all.
1 - 20 of 24 Posts
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