Once the instrument panel is removed from a 300E, there is a cover at the very top center of all the HVAC mess. At the very front of this cover, there are two phillips screws that are almost inaccessible due to the protrusion of sheet metal rearward from the base of the windshield. I have tried a standard length, short length, stubby and offset phillips screwdrivers to no avail.

When in the military we had a flexible shaft phillips screwdriver for getting to a difficult to access screw on a missile control unit. If I had that I think I could get them. Has anyone ever seen such a screwdriver and where can I get one?

Does anyone have any suggestions for accessing these screws?

It is obvious that these two screws were put in place before the HVAC assembly was put in place. I am convinced that the person that designed this mess will spend eternity in hell changing evaporators on 124 cars.

If I can get these two screws out I think I will be able to replace the heater core without too much further trouble.

Most everything else is going reasonably well with my podectomy. Of course, I have not yet started back together.

Thanks for your help,

Thanks for the insight...

Larry -

No suggestions, unfortunately. I did mine on the bench - I don't even remember the two screws causing you problems. To the best of my recollection, you are the first to attempt a heater core replacement with the box in place. I do recall how tightly the box tucks up under the windshield base. Maybe we can get a professional tech to chime in.

Worst case, it's not that hard to pull the hvac box. Removing the console sides isn't much work. The radio just unplugs. You already have the radiator drained, I presume. So it would just be a matter of evacuating the a/c system and disconnecting the expansion valve. The heater box itself is secured by five easily accesible nuts; it just need be pried away from the firewall. I'd guess it's about an additional hour for you to just pull the whole box.

Of course, then you need new o-rings and probably a dryer. And the expansion valve can be uncooperative when it comes to getting a good, leak-free seal. Plus side would be the opportunity to pull the evap and give it a good cleaning.

Best of luck,

- JimY

Jim,

Thanks very much for the response. I expected this to be at least one of the replies.

I REALLY don't want to disturb my perfectly tight evaporator! I have found two special tools online that may allow me to get these two screws out. These two screws are all that's between me and the heater core.

Before I would disturb the evaporator, I will just leave the heater core. It is not leaking currently.

Thanks again for your reply.

If anyone else has a suggestion I will really appreciate it.

Have a great day,

I was going to suggest just leaving the heater core in place, but knowing you, didn't think that would be an option. I tend to agree with that choice; the heaters on these cars just don't go bad.

Glad to hear the task is going reasonably well. Like you, I found the work easier and less intimidating than expected. Although I share your disdain for working under the dash, it does have its advantages - there are no huge, high torque fasteners which won't break loose, and it's reasonably clean - nothing is covered in grease and oil.

Let us know how you make out with those two stubborn screws.

- JimY

Hey Larry,


I remember that type...


heres a source, google, .6 secs :





http://www.surrayluggage.com/flexscrewsta.html


http://doityourself.com/store/621239625187.htm

Best Rgds, Jeff

Jim,

I don't know if I mentioned it earlier in the thread, but a year or two ago the heater core developed a slight leak that I fixed by flowing some hot water with bars leaks through the core. That is a patch at best, so I want to replace it if at all possible.

fish4stripers,

Thanks for the links. I just got back from Sears and got every gadget they had that might have a shot at accessing these screws. If none of these snake oil gadgets work, I will order one of those flexible drivers. Thanks a bunch.

Have a great day,

Gotcha Larry,

I figure you're anxious to finish and dont want to order online unless absolutely necessary.

Other sites showed up too,heres one:

http://www.toolbarn.com/cgi-bin/products.cgi/T2641/

One other thought is radioshack or other electronic places locally. Soetimes they have different/odd tools.

best of luck

Jeff

I think one of my gadgets from Sears is going to work. It is a fit all driver with several bits including a number two phillips. It has a universal joint on the end that is about an inch long plus the protruded portion of the bit. It wobbles about 30 degrees and it BARELY fits in place on the screw. I managed to turn the screw about two turns during my quick test.

After I get done for the day, I'll go back out there and see if I can get both screws out. There are two brackets that these screws hold in place as well as securing that top HVAC panel. The brackets hold about 4 vacuum lines, so the screws REALLY need to go back in place. If it weren't for that I could consider leaving these two screws out, since there are two other screws holding it nearby. I really hate to leave screws out of anything, but in the past I have done so under certain circumstances.

Maybe this will get the project moving along again.

Thanks to all,

GOT 'EM!

I loosened the bolts and nuts that hold the brace along the top of the firewall and loosened the crossmember and got just enough room to get the screws out with my wobble joint screwdriver.

Once the cover was off, I then had to disconnect the plastic clamps that hold the water pipes on either side in order to push the pipes back far enough to pull out the heater core. Once out, I was able to change the pod in front of it. That one has to be changed from the inside. The only pods remaining to be changed are the fresh air.

Thanks for the help and suggestions,

BTW, I wonder if I should put the new o-rings on the heater core pipes dry, or is there a sealant that should be used?

Thanks,

Larry

I asked about this when doing the 190e heater core. I was told by a Meredes Shop Tech that they do them dry. The reason was when gooped with silicone etc, they will tend to deflect/slip instead of seal. This seamed right and so far so good.

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

haasman,

Thanks for the reply. I suspected this to be the case from looking at the original o-rings.

I am scared to death that I will get something wrong and have to pull the instrument panel a second time. Since they made everything so tough to get to they should have put the instrument panel on a hinge.

This is the way the instrument panels are mounted on some of the big rigs.

Have a great day,