Death Rattle

[Guest]

OK, like I need this. Lately, when I crank my car from cold, I hear a nasty rattle coming from somewhere near the bottom of the engine. Kind of a muffled clanking noise that goes away after about 20 seconds. Now, I really need to throw her back on blocks and look around underneath and check my headers, exhausts, etc. but this is a new noise that is quite unsettling. Almost as if my crank has an issue. Question, there is no way in heck that a crank bearing cap or something could have come aloose, is there? Really don't want to drop the pan, again, to look around. The engine runs fine after warmup, with no noise. We drove the 3+ hours from Natchez last month at 70+mph without a hitch. Gotta be something rubbing. That, plus the whistle when it warms up, has me rattled. Guess it is time to do the gorilla thing and pull the valve cover to check the rockers against the cam. Just gotta get some relief from this rotator cuff pain.

 

[Tinkerman]

din't know the TR6 had a rotator cup, heh

 

[Brosky]

If it's any consolation Bill, you would have been towed long before the three hour drive if it was crank related.

Could the header or exhaust pipes be hitting the frame, ever so slightly, then moving away when expanded a fraction of an inch after warm up? My car has a slight noise from the pipes, but only when shutting down and I know that it's hitting, but haven't crawled under to find out why.

What whistling noise are you talking about? Whistles are usually vacuum leak related.

 

[donbmw]

Bill I had a connecting rod cap come loose on my TR3 that made a sound like you have.

Don

 

[Tinster]

Oh Bill, I sure hope it's not an escaped Chupacabra.
They are the devil himself to get rid of.

Ask me how I know!

d

 

[14dna]

Bill
I own a Miata that has the exact same noises that you describe.
It is an exhaust leak. The pipe moves a little when cold and expands enough to take up the slack when warm. The whistle is exhaust escaping around the manifold to pipe gasket.
Check this first as it is by far the easiest.
Dave

 

[RonMacPherson]

First thing I would check is the exhaust pipe through the frame, possible the exhaust hangers have stretched, and the pipe is contacting the lower panel.

 

[jessebogan]

How quickly does the oil pressure gauge register? If it makes the rattle, and the gauge begins to register as the sound disappears, then you have a potential lower end problem. the first thing to check if that is the case, will be the oil filter. You may be having a "drain back" issue, and are hearing some bearing rattle until the filter fills up again. Change the filter, or even better the brand of filter, and see what happens. Good luck!!!

 

[Guest]

Hey, Jesse, I just changed to a "better" oil filter, the NAPA Gold 1516, which is made by Wix. Been using the Fram 3600 for years with no problems, not sure why I changed. Guess I will drop the oil and try that. The oil pressure goes up quickly, once the engine turns over a few times, even if under starter power. The other option is to drop the pan and start checking the oil pump and everything I can get a wrench on. Strangely enough, when I put a new oil pump in last winter, I blew the new one right of the bottom of the block. Installed another brand new one and that one works. Both County brand.