How-To: COOLING FAN crunching noise source found/FIX!!!

[GoofyTimL]

It's the side seals between the radiator and the housing. Somehow they are not staying put and get sucked into the housing and torn up by the fans. The fans themselves are just fine.

I decided to start a new thread so that this is easy to find for those who want to check their SRT8, or need to address this very issue. It certainly is a DIY possible task. vvv90... please consider this for the TECH TIPS section. As far as I know it will apply equally well to the 5.7L fan housing as it does to the 6.1L engine cooling system.

This may take me several posts to document with pictures and commentary so until I indicate that I'm done, please don't post a response.

[GoofyTimL]

Two weeks ago, while on vacation we noticed an alarming noise from the engine bay one morning. It sounded like a rock grinder. At the time I didn't know whether it was within the engine or something else, but it quickly became obvious it was something to do with the fans, not the engine.

I contacted FnkyChkn over at LXF to see if it was feasible for a non-gearhead like myself to investigate further, or should I just take it to the dealer. He provided the following schematic diagram and procedure...



(1) RADIATOR FAN ASSEMBLY - (2) ELECTRICAL CONNECTOR - (3) UPPER RADIATOR HOSE

1. Disconnect negative battery cable.
2. Partially drain cooling system (Refer to 7 - COOLING - STANDARD PROCEDURE).
3. Remove upper radiator hose (3).
4. Disconnect cooling fan electrical connector (2).
5. Remove cooling fan mounting bolts.
6. Remove radiator cooling fan assembly (1) from vehicle.

Of course you have to remove your air intake (stock air box or CAI) back to the throttle body. You also need to move the electrical snake that crosses over the radiator up and out of the way.

I see no reason (unless your paranoid about electrical issues) to remove the battery cable. I did not. The only electrical items are the IAT sensor and the fan control cable. Both those are foolproof connectors and pose no difficulty. He also indicates to remove the top radiator hose. I also found this unnecessary. You simply need to move it out of the way.

I did this using a short bungie chord and the fuse box terminal as the anchor...


This is a good time to check inside the Tstat housing connector and down inside the radiator hose itself. When I did this I didn't particularly like the look of the Tstat housing... it looks as if it was painted internally, and of course the antifreeze does a number on paint. But what was left didn't wipe or scrape off, so I left it.


The fan control chord connector is on the fan housing, just above the low-speed fan and easy to access and disconnect once you've moved the radiator hose. Then there are only two bolts which hold the fan housing assembly in place. The first is located just under the other end of the top radiator hose... it can be accessed without removing the hose entirely. The bolt head size is either 10 mm or 8 mm... I don't recall now.


The other bolt is on the opposite side in a similar location...


I was concerned that there might be a third and fourth bolt down below, but was pleased to find that the connections on the bottom side are merely slide on positioning pins. It took a little bit of persuasion to lift the fan housing out of the engine bay. You have to work the bolt tabs and the lower positioning pin tabs past the radiator hose on the passenger side and the two small hoses on the driver's side.

[GoofyTimL]

When I got the housing out I examined it closely. I saw no impact marks, and no wear marks on the housing or fan blades. I heard no rubbing and observed no wobbling when rotating either fan blade. I was baffled. Then I looked down into the engine bay to examine the back side of the radiator.



Clearly there was "minor" damage to the fins, but in no discernible pattern that I could detect. Then I saw something laying down near the bottom, and in fact there were two pieces. I didn't take a picture until I had them laying on the table with the fan housing...


These two stips of plastic/rubber were totally chewed up! Here's a closer look.


But it was not obvious to me where they are supposed to be mounted. They are the right length to go along the side of the housing, but... There is no tell-tale sign of something that slipped off the housing (like a dirt line), and they didn't appear to be curved in the way that would follow the outer edge of the fan shrouds.

[GoofyTimL]

Then it occurred to me that perhaps they mounted on the edge of the radiator itself. There seems to be a place where the plastic part could mount and leave the rubbery fin reaching out to seal to the fan housing.


So I don't know if this is correct, but I tried a test fit to visualize my theory...


Wherever they go, they clearly were/are not reusable so I simply put the fan housing back in and reconnected everything. It is difficult to see anything AFTER you put things back together, but I did have a little angle to view down beside the washer fluid and ABS brake distributor. There clearly is a gap now between the housing the the edge of the radiator... as indicated by the arrow.


I would appreciate it if some of you, who have NOT experienced this fan issue would check and maybe take a picture of a similar visual in your car to verify what the side seals are supposed to look like. I would think you will not be able to see the radiator edge as you can in the picture above.

I plan to take the two destructed pieces to my local dealer on Monday morning and get or order (under warranty) replacement parts. I think I probably can install them myself, but to maintain warranty considerations I probably will schedule a time when they can install them... with another dozen donuts of course!

Ok... I'm done. Comments?

[GoofyTimL]

Originally Posted by bruno

GTL,
You are pure genius! Fabulous troubleshooting report! I already linked the other similiar thread to this one. Not sure if I'm bright enough to take a photo of what you are requesting. Do I have the same parts on my 5.7?

bruno

Bruno... When I was done I tried looking at and feeling around the Heritage Edition housing, and I couldn't tell for sure whether it was or looksthe same or not. After spending a couple hours hunched over the SRT8, I didn't feel like pursuing it further.

But... the H.E. has nearly 19k miles now, and has never given any indication of the same kind of noise.

The MSRT8 did this with just over 5k miles... and the only other vehicles I've heard about are SRTs as well.

[GoofyTimL]

Thanks folks. Took the pieces to my dealer this morning and it certainly raised eyebrows. Service writer said they would order replacements and be ready for the reinstall on Monday morning... unless they call me later to say delivery will be delayed.

So maybe I'll be able to take pictures of how it should look AFTER they are done. Then I'll have my fingers crossed that it doesn't happen again.

[YoungMedic23]

GOOFY!!! You beat me to the solution by one day buddy! About an hour ago my partner and I at work spent two hours pinpointing the sound after a couple co-workers said my car sounds like it's broken! My arm wouldn't fit that far down but his did. I happened to have a little hole in my bottom engine cover and i pushed the mangled pieces up to him and he pulled them out! I was just bout to post a thread with pics!!! Now my arms are slightly burned and have a couple scratches but no big deal! No more rock crunching! What a coincidence u found it and posted exactly one day before me!!! AMAZING!

I'm not replacing mine.....no way do i ever want there to be any possibility of that happening again! And besides i don't think it will do any harm at all.

If you think about it.....as long as we've all been ignorant of the sound cuz it's only heard from the outside with the passengers fan goin.....our cars have done FINE with these culprits flying around on the bottom of the housing with NO HARM. I SAY LEAVE EM OFF!!!

[GoofyTimL]

I'm going to replace them one time at least and give the design another chance. IF they fall off again, then plainly it's a design flaw/weakness and they will stay off, or I'll try another means of sealing the sides.

[GoldNnasty]

Hi Tim,

Curious..... did you look at the HE to see if it uses the same "seals"?

After looking at your great "how to" photos, I am thinking the seals were not installed properly, ?( you know the old saying..... "probably done on a Monday or Friday")

I am not near my "C"....so I'll be lazy and ask you. It could be possible that the seals are to mount on the outside of the fan-radiator assy.

This is totally a sepculation on my part.

Hope it gets resolved for everyone

[GoofyTimL]

I tried looking at the H.E., but frankly... I was tired of being "hunched over" the MSRT8 engine bay and had little patience to look deep into the H.E. bay. in order to be able to see anthing really, you have to remove the air box and intake, and the upper radiator hose.

I'm not going to do that with the H.E. until I'm ready to install a 180 Tstat over there, which is going to be a while yet. But from what I could see, it looks like it might be a little different and I've not had any problems with the H.E. over 15 months and 19k miles.

The MSRT8 developed this problem around 5500 miles. As far as the question regarding to which surface the seals mount, I don't think they go on the fan housing. The hard plastic channel looks to be more the dimension of that side piece of the radiator itself. The side of the housing is thin, has not "locking" groove, etc., nor accumulated line of dirt/dust that would indicate anything like that actually was attached to it.