Air Cleaner Woes. Help. Novice etc 81 240D - PeachParts Mercedes-Benz Forum

pj67coll · #1 05-08-2006, 08:46 AM

I've done a search but cant find anything specific to this issue. I'm a complete novice mechanically but figured after reading up on Air Cleaner mounting issues that it would be no problem for me to fix mine. So I ordered the parts and set about removing the air cleaner this weekend. Questions...
1) Is a 240D supposed to have the mounting bracket (the one that's always cracking at the back) because mine doesn't?
2) If not. Then it seems the rubber mounts screw straight into the holes in the intake manifold?
3) Only the front one screws in. The rear mounting hole in the intake manifold itself is stripped and the outside,, I dont know what they've done with that so I haven't had the courage to take apart yet. You'll see what I mean if I can get the pic to post. What can I do short of buying a new intake manifold?
4) Is the rubber seal that goes under the air cleaner the same for 240D's as 300D's. The one on the car looks different to me than the one shown in Fastlanes online catalogue.

The picture is too big to post here so I'll try and post a link to it.

- Peter.

t walgamuth · #2 05-08-2006, 09:06 AM

i think maybe on a 240 it does screw directly into the intake. if the threads are stripped you can prob install a thread insert, the brand name escapes me at the moment.

the name is helicoil.

tom w

vstech · #3 05-08-2006, 11:06 AM

if you clean out the hole real well and fill in the hole with jbweld the mount should hold quite well. I would put a very thin layer of antiseize on the mount threads before putting it into the jbweld so you could unscrew it when it brakes later...
helicoil would be a better alternative, but finding one that small may be a problem.

rhodes2010 · #4 05-08-2006, 11:15 AM

Agreed on the above points.
Mounts go directly into manifold.
If it is stripped helicoil if you can get one, JBweld should work fine.

pj67coll · #5 05-08-2006, 11:54 AM

Thank's for the reply's folks. I shall indeed try the helicoil route. But if that's unsuccessful, how do I use the JB Weld? Surely if I place the mount in the JB before it's set it will stick fast and become one with the intake manifold?

- Peter.

trontek · #6 05-08-2006, 05:10 PM

.....

pj67coll · #7 05-10-2006, 01:08 AM

Ifound what appears to be exactly the right size kit in Autozone. It's OEM 6.3mm for 27 bucks. Cant believe my luck but the screws in the new rubber mounts appear to fit perfectly in the new threads. I'm going to photograph the entire operation with a digital camera. Just wonder if there would be any interest in seeing this under the DIY threads? Moderators anyone? Assuming I dont screw it up of course.

- Peter.

pdrayton · #8 05-10-2006, 09:40 AM

I'd be interested in seeing it. I have the same problem and was going to go the JB weld route.

Still, $27 might be more than I wan tto pay to fix it. I have it held down with a piece of wire at the moment....

pj67coll · #9 05-14-2006, 02:49 PM

OK. So I did this job yesterday. The first hole that was completely stripped was a perfect repair. I didn't have to drill it out at all, I merely screwed the tap in by hand and then inserted the new thread. Perfect results. Fortunately the second hole did not need tapping. Merely had to remove the rubber mount who'se top section had sheared off at some stage and screw in the new mount. So that's two out of three mounting holes fixed. Unfortunately the third hole (front one) which was the only one that seemed to be okay turned out to be a problem. I tried installing a new mount in it but it just wouldnt go further than a few mm into it and stripped the threads. So then I tried tapping this hole as well but nothing I did would get it to work like the first one did. I'm stuck with two options at this point. I either drill out that hole and attempt to double up on the inserts, by using a larger size than the original and then inserting the original sized thread inside the larger one... or I have to go the JB Weld route. Which I've been trying to avoid. I'll keep updating this as I decide. I photographed this procedure but the pictures are all too large to post on this forum so I'll see about reducing them and maybe getting them in the DIY section. At least I now have two out of three mounts holding the air cleaner instead of only one so at least I'm two thirds of the way there.

- Peter.

pj67coll · #10 05-30-2006, 10:45 AM

Update for those who care. I fixed the final mounting with JB Weld. I had to drill out the mounting hole and then fill it up with JB Weld into which I inserted a new mounting with a lot of anti-seize on the threads and the thread insert screwed all the way on to the mount. I left it for 24 hours to set and so far after about sixty miles of mixed highway and town driving it's holding up great. I have photographed the entire fix and hope to get some pictures up somewhere soon. Thank's to all who offered advice. I never would have had the courage to attempt this otherwise.

- Peter.

Ken300D · #11 05-30-2006, 11:33 AM

I've had good success with the JBWeld method for stripped bolt holes. If there is sufficient clearance, I change the mounting method from a bolt to a section of threaded rod and a nut/lockwasher. The threaded stud gets screwed into as much thread as is left and secured with JBWeld. The the nut/lockwasher serves as the fastener. Not a stock result but effective and quite cheap.

Seems to hold up well under vibration and heat - the example I'm thinking of is on the intake manifold of a small logsplitter engine - LOTS of heat and vibration.

Ken300D

1983/300CD · #12 05-30-2006, 04:59 PM

You can also make the diameter of the hole a little smaller with JB Weld, then tap it out once it's set. But, if the "plugging it in with anti-seize on it" method works, then great! Saves a step.

pj67coll · #13 05-31-2006, 12:19 AM

I had thought of using the JBWeld to decrease the diameter of the hole and then tap it out again but wasn't sure if that would work. In my test run with a plastic bottle cap and and the old mounting I found the completely new plug with antiseize worked fine - to my amazement. So I went for it and it seems to have been just what the doctor ordered.

- Peter.