Lite grinding from between engine/transmission

[DiamondStarMotors]

I have been on the forums for the past couple hours searching for this same problem to see if this already had been answered. No one described the same problem as mine.
No matter what gear, including neutral, I hear a lite grinding noise that gets louder with the engine revving up. It has really started to bother me.
And i am unsure of where to go as I am new to the whole wonderful DSM world.
Any help would be much appreciated. thanks in advance.

 

[luv2rallye]

Does it change with clutch pressed in or out?

 

[DiamondStarMotors]

no that's what throws me off. It doesn't matter if the clutch is in or out.

 

[ampsyco]

are you sure its in the trans and not the engine ?? maybe an idler pulley or tensioner pulley ??

 

[DiamondStarMotors]

I guess i really don't know, it just seem like it's coming from the driver side.
I did a little more investigating today and it seems as if it makes the noise when the rpm's fall and not so much when they are getting higher. The noise is at it's loudest between two and three grand.
if it is tension or idle pulley, could there be even more trouble down the road if not fixed right away?

 

[Clever Gs-t]

Regardless of where the sound is coming from, it definitely sounds like a bearing failure. An idler or tensioner bearing for the accessory drive belts would result in a thrown belt and loss of a/c or voltage from the alternator. But a tensioner or idler bearing on the the timing belt side would be catastrophic and needs to be addressed ASAP. So figuring out more specifically where the noise is originating is of the up most concern.

Good luck!!

 

[DiamondStarMotors]

and it's not as loud as it use to be...

if it is on the timing belt and goes to the next step. What will it "f" up when it gets there?

I have to drive myself to school tomorrow and all this worries me.

 

[Redslayer]

and it's not as loud as it use to be...

if it is on the timing belt and goes to the next step. What will it "f" up when it gets there?

I have to drive myself to school tomorrow and all this worries me.

the 420a engine is an "interference" engine which means if the timing belt breaks (or comes off) while its running 9/10 times your valves meet your pistons resulting in valve damage.

I had a 91 Protege snap a timing belt (my first car) and it was an interference engine. It bent multiple valves.

It's still sitting in my back yard 7 years later.

 

[DiamondStarMotors]

Yeah I wanna keep this car for after college and maybe make it a project.
Who's great idea was it to make an engine that does that crap?

 

[Redslayer]

Yeah I wanna keep this car for after college and maybe make it a project.
Who's great idea was it to make an engine that does that crap?

I've often wondered that myself. But what can we do

The cover is a PITA to take off on the 420a too, I actually got pissed off at mine and drilled a hole through the wheel well to get one of the bolts out . But there should be a small cover held on by a single bolt on the timing belt cover, take that off and check the play in your belt for starters. And then see if you can maybe listen close near that side while its running to see if the sound is in that area.

The only problem is, everything else is in the same area, so it may be near impossible to tell for sure.

If you aren't sure, but think its a a tensioner (I.E. you narrow it down to that side) , then you could always pull the belt off the power steering/AC. And see if you still hear the sound

There is no tensioner on the 95 420a alternator. So you should be fine leaving that belt on.

Edit : If you can avoid driving it until you know its not anything to do with the timing belt, I would do so. And I'm sure its common sense, but don't try to mess with the belt while the car is running

If you absolutely must drive it, I'd go super easy on it. But I recommend parking it until you can be sure it's not timing belt related.

Good night, and good luck! I'll check back in tomorrow to see if you've figured anything out.

 

[DiamondStarMotors]

I don't know if this makes a difference, but on idle when i stand by the driver side front wheel well, the sound is very subtle but almost sounds like it is coming from the back of the engine.

 

[Redslayer]

I don't know if this makes a difference, but on idle when i stand by the driver side front wheel well, the sound is very subtle but almost sounds like it is coming from the back of the engine.

Its so hard to judge sounds from under the hood. I had what sounded like a valve tap, sounded like it was coming from the engine itself.




Turned out to be a loose radiator fan . Like I said, If I was you I'd make 100% sure it wasn't timing belt related, because if that fails you're screwed. It could be something stupid though. like something loose rattling about, or a bad intake manifold gasket (which is on the back side of the engine). Or even a bad exhaust gasket right before the cat (which lines up almost perfectly with the back of the engine ).

But you said it was a grinding noise, so I'd check all the timing components first just to be safe.

Now I really need to sleep haha, don't let it stress you too much, just take your time and give it a careful look over. These cars tend to mess with your head if you let them haha. goodnight!

 

[chadjoe]

my Gs-t did the same thing and it ended up being the flywheel bolts backing off.

 

[DiamondStarMotors]

once i pull off the cover of the timing belt, how will i know if the bearing is bad? pull the belt away a little and spin the tensioner a little?

 

[Redslayer]

once i pull off the cover of the timing belt, how will i know if the bearing is bad? pull the belt away a little and spin the tensioner a little?

You shouldn't be able to pull the belt away from it. If you can you have problems.

 

[DiamondStarMotors]

oh ok good thing i didn't try that. so what do i do once i get the cover off?

 

[Redslayer]

oh ok good thing i didn't try that. so what do i do once i get the cover off?

Well if you are going to or already have pulled the whole cover, if there is no visible damage to it, and you can't tell by just wiggling it or whatever, make sure you hands are clean of any oil/grease and try to twist the timing belt, you shouldn't be able to turn in beyond sideways (basically you'd go from look at the edge of the belt to the bottom or top of it) . Don't strong arm the thing , But if it wont go past half twisted, then its tension should be fine.

At that point, you could start the car and see if you hear a problem. Make sure you have everything away from the timing belt, no tools or wires or anything that can get near it. It will run off the battery alone.

But before you pull the cover completely off (if you haven't already), when you pull the belt off the Power steering spin that tensioner below it and make sure its ok and that's not what you're hearing.

If only you lived in Maryland or Delaware, I'd just roll up there and take a listen .

 

[DiamondStarMotors]

Well if you are going to or already have pulled the whole cover, if there is no visible damage to it, and you can't tell by just wiggling it or whatever, make sure you hands are clean of any oil/grease and try to twist the timing belt, you shouldn't be able to turn in beyond sideways (basically you'd go from look at the edge of the belt to the bottom or top of it) . Don't strong arm the thing , But if it wont go past half twisted, then its tension should be fine.

At that point, you could start the car and see if you hear a problem. Make sure you have everything away from the timing belt, no tools or wires or anything that can get near it. It will run off the battery alone.

But before you pull the cover completely off (if you haven't already), when you pull the belt off the Power steering spin that tensioner below it and make sure its ok and that's not what you're hearing.

If only you lived in Maryland or Delaware, I'd just roll up there and take a listen .

I haven't done a single thing yet, I'm at school.
So i check the power steering tensioner first, it that's not the culprit then i take the timing cover off? Then check the tension of the timing belt and look for visible damage?

 

[Redslayer]

I haven't done a single thing yet, I'm at school.
So i check the power steering tensioner first, it that's not the culprit then i take the timing cover off? Then check the tension of the timing belt and look for visible damage?

Yeah, you can check the belt tension without removing anything but the little cover at the top, #4 on this shows it - Timing Belt VFAQ

Number 6 shows the layout. That's the guide I used to help me do my timing belt when I replaced it. But there are also some good ideas to help along the way on the forums. So look around if it comes down to that.

This is the pulley layout for the power steering @ AC on our cars - http://img510.imageshack.us/img510/9507/copyofscanfj2.jpg

Just happened to find a pic with the part in question circled in yellow

For your sake I hope its that and not one of the pulleys for the timing belt, just for the PITA level which the timing covers are in these cars.

 

[slinkmerc]

I haven't done a single thing yet, I'm at school.
So i check the power steering tensioner first, it that's not the culprit then i take the timing cover off? Then check the tension of the timing belt and look for visible damage?

I just got done doing a timing belt and water pump and timing bearings on my 420A if your car sounds anything like mine FOR THE LOVE OF GOD STOP DRIVING IT video below
Rattle noise coming from pulleys on eclipse - YouTube

if it sounds anything like mine it more than likely means you'll need a timing belt,water pump, hydraulic tensioner, idler and tensioner bearings (or pulleys what ever you like to call them)

if you post a video of what it sounds like then we could probably help you out a bit more

 

[DiamondStarMotors]

Mine is nowhere near that bad...
I will post a video soon. maybe tomorrow or saturday.

 

[Chrispy0530]

the 420a engine is an "interference" engine which means if the timing belt breaks (or comes off) while its running 9/10 times your valves meet your pistons resulting in valve damage.

I had a 91 Protege snap a timing belt (my first car) and it was an interference engine. It bent multiple valves.

It's still sitting in my back yard 7 years later.

Correct me if I'm wrong, as I'm curious but I thought the 420a's were non-interference motors?

 

[Redslayer]

Correct me if I'm wrong, as I'm curious but I thought the 420a's were non-interference motors?

If it wasn't, that would be news to me. Everything I've read so far has said it was. I checked around a lot when I was about to do my timing belt.

Edit : After some searches the only thing I see that isn't is the sohc A588 used in the 97 neon and other SOHC engines. The 420a and 4g63 both list as interference engines.

 

[gprix1]

I had a noise like that too and as a test I pulled the AC belt off and the noise dissapeared so in my case it was either A/C clutch or the tensioner pulley.

 

[Tha Fella Dylan]

Mine was making the same noise but with a little whine at the top. Didn't wanna risk and towed it to my mechanics shop. He said my timing belt tensioner was effed. That would be my guess.