1997 V8 Cold Start Rumble

[Meadowlark Lemon]

Morning everyone, apologies if this a double post - I tried to post yesterday, but I am not seeing it anywhere.

My 1997 V8 Mountaineer makes a low rumbling noise for a couple seconds after a cold start. The colder it is, the longer it lasts. I've started it with the serpentine belt removed and it does not make the noise, so it appears to be somewhere in the accessory drive. None of the accessories or idlers feel especially crunchy when I spin them by hand so I am looking for some advice on what this might be before I start throwing parts at it.

I have thrown two new belts at it, one regular length, and a second that bypasses the A/C compressor. Neither seemed to help much.

Thanks!

Andrew

 

[410Fortune]

In my experience that noise you describe could easily be the alternator going out the bearings inside fail
Especially if all the other pullies seem fine when you spin them by hand

If it is an air noise, like a b25 taking off then it could be time for a new fan clutch

Otherwise you just have to spin everything by hand to try and find the culprit

 

[Meadowlark Lemon]

Good info. Thank you!

 

[Fix4Dirt]

when its really hot out pulling up the grapevine the explorer sounds like its gonna enter orbit with the amount of fan noise haha

 

[Lee's Automotive]

Morning everyone, apologies if this a double post - I tried to post yesterday, but I am not seeing it anywhere.

My 1997 V8 Mountaineer makes a low rumbling noise for a couple seconds after a cold start. The colder it is, the longer it lasts. I've started it with the serpentine belt removed and it does not make the noise, so it appears to be somewhere in the accessory drive. None of the accessories or idlers feel especially crunchy when I spin them by hand so I am looking for some advice on what this might be before I start throwing parts at it.

I have thrown two new belts at it, one regular length, and a second that bypasses the A/C compressor. Neither seemed to help much.

Thanks!

Andrew

That noise your hearing would be the fan clutch it's definitely annoying id recommend replacing it with a Hayden severe duty clutch and checking your fan blades for cracks if you find cracks replace it immediately

 

[Meadowlark Lemon]

Thanks again for everyone's input. Right now I am leaning toward blaming the fan clutch with the idea being the fluid inside the clutch collects somewhere it is not supposed to be overnight, and gets flung out to where it is suppose to be quickly after the engine starts. Takes a little longer when cold due to increased viscosity. Also, this is probably the cheapest to diagnose since I can pull the fan and try it out the next morning.

I did put a mechanics stethescope on the PS pump, upper idler, water pump, and alternator and none of them were particularly noisy. Not really a fair test since the noise abates so quickly, but I was hoping one would be a little grindier sounding than the others.

Thanks! Andrew

 

[Meadowlark Lemon]

Good morning,

Still working through this startup grumble. Last month I said I was going to pull the fan clutch because it was 'cheapest to diagnose'. Well, it certainly is free money wise, but turning expensive in the time domain. Any pro tips on getting this thing off? I've read a bunch of threads and I've got the good 36mm fan clutch wrench from O'Reilly, and the 'universal' fan clutch holder. Part of my issue is I cannot seem to find room to fit both tools onto the water pump / fan clutch at the same time. The 'universal' fan clutch holder is a bit of a pain to get properly adjusted and to keep on the two pulley bolts. I've tried the clutch wrench from the top of the engine and the holder from below, but mostly just got frustrated. Going to try the holder from above and clutch wrench from below next.

Any pro tips to share? Maybe some good photos or a video of the best way to position these tools?

Thank you!

Andrew

 

[410Fortune]

Both tools from the top, the fan wrench you will use the space in front of the alternator to work. Remove the air intake tube of course. You will be pulling upwards on the wrench while the holding tool is pressing downward on the drivers side

Set the holder on two of the waterpump bolt heads, rotate it so it sets up against something on the drivers side, so when you start to loosen the fan clutch nut the holder tool with be pressed up against an object. Now slide your wrench in there
Use a ratchet as extension for extra leverage

With the right tool they will both fit in there and one man can do it. Once you break it loose the fan will spin right off

 

[Meadowlark Lemon]

Both tools from the top, the fan wrench you will use the space in front of the alternator to work. Remove the air intake tube of course. You will be pulling upwards on the wrench while the holding tool is pressing downward on the drivers side

Set the holder on two of the waterpump bolt heads, rotate it so it sets up against something on the drivers side, so when you start to loosen the fan clutch nut the holder tool with be pressed up against an object. Now slide your wrench in there
Use a ratchet as extension for extra leverage

With the right tool they will both fit in there and one man can do it. Once you break it loose the fan will spin right off

Thanks for the quick reply. When you put it like that, removing the air intake tube sounds like an obvious first step, but I have not done that. Sounds like a game changer. Thank you!!!!!!!

 

[Meadowlark Lemon]

Well, I managed to get the fan clutch separated from the water pump over the weekend. Turns out my truck is a RH thread, and I was trying to remove it as though it was a LH thread for the first hour.

Removing the fan & clutch certainly changed the characteristic of the noise. The startup rumble is pretty much gone, but now there is a higher pitched whining type of noise that very definitely is coming from the area of the water pump. Increases frequency with RPM. I cannot imagine this is normal, but I am debating whether it is the water pump or if it could be the notorious cam position sensor chirp. But I would not exactly call it a chirp. At least we are making progress!

 

[410Fortune]

A Mechanics stethoscope can help pinpoint the noise (or long screwdriver)

With 3ea 13mm nuts and some wires you can remove the coil pack tripod and get direct access to the cam synchronizer
You can remove the two top 5.5mm screws and add a couple of drops of oil to the synchronizer
This will quiet any chirp for at least a short time
You can also do a visual inspection of your synchro and sensor

Look for excessive rouge or a broken sensor

If the waterpump bearings were worn out hopefully the weep hole would be spilling a little coolant (the weep hole is designed for this)

 

[Meadowlark Lemon]

Thanks again for the quick reply. I am using a stethoscope and the character of the WP noise definitely changed with the removal of the fan and clutch. Much less rotating mass probably contributed a lot. I've been chasing a general noisy accessory drive in addition to the startup rumble, so things are starting to piece together. Only thing is I did not think to put the stethoscope on the cam sensor while I was under the hood, so one more thing to check. I really am trying to avoid replacing the water pump, I understand broken bolts are likely in my future if I follow that path.

I do have some coolant leaking but I have not been able to pinpoint the source - somewhere up front, could be thermostat, WP, or timing cover.

I am kind of weighing the urgency of any of this work. The leak is very minor, but I don't want the WP to give up catastrophically at 70 mph one day....

Thank you!

Andrew