striped threads on oil cooler - PeachParts Mercedes-Benz Forum

jamesNB · #1 02-19-2008, 02:27 AM

So I was trying to re-install the oil cooler and the lower line wouldn't go on. I pulled it back out, cleaned up the stud with brake parts cleaner and notice a touch of striped threads at the top of the stud. I tried using the new oil line to get the threads started but no luck.
I don't know if I stripped the threads removing the line, trying to get it back on or more likely, that was why it's been leaking at that spot since I bought it. I thought a new hose would take care of things.
Well, I called the only two machine shops in town and they don't deal with metric sizes. I checked a tool store on the way home and they had a tap and dye set that had an 18mm dye in it (I'm guessing that's the size" but it was $87.
I was planning to run the proper sized die down the threads to clean them out. I think I can handle it but I would rather a machine shop do it. If worst come to worse, I'm thinking they could cut of the old piece and weld/braze a piece of aluminum stock on the cooler and thread it. Anyway, I think it would be cheaper than the $550 for a new oil cooler.
So what do you think?
1. Buy the tap and Die set; clean up the threads myself, making sure everything is nice and level as I cut?
2. Find a big city machine shop that has metric tools and could replace the nipple if needed?
3. Spend the $350 for a new oil cooler?
Anybody try this personally?

BillA · #2 02-19-2008, 02:58 AM

how about a used oil cooler off eBay ?
I spent $50, have as a spare as my lower connection did not want to seal initially

charmalu · #3 02-19-2008, 04:08 AM

I don`t know what part of the country you live, but do you have any pick n pull type wrecking yards? I would check there first before buying a new one.
There is a replacement piece for the stripped nipples from MB. I`ll have to check through my notes and find it, it`s some where in my pile scratch paper and stuff

.

when you remove the oil lines the threads sometimes strip being aluminium with the steel line attached. I use some anti siez when I reinstall them.
use a back up wrentch on the oil cooler. a 7/8 inch.

FOUND IT. part number 915013 - 013002.

www.peachparts.com/shopforum/showthread.php?t=104244

Post# 5
charlie

rs899 · #4 02-19-2008, 07:05 AM

Pick n pull is your answer. When you get one- cut the hoses with a knife. Put it on your bench and hacksaw or dremel across the nuts. Spread the threads apart with a screwdriver to keep from wrecking the fragile alloy. In my experience, very few of these will come apart without damaging the threads.

LilTimmy · #5 02-19-2008, 10:50 AM

Quote:

Originally Posted by rs899

Pick n pull is your answer. When you get one- cut the hoses with a knife. Put it on your bench and hacksaw or dremel across the nuts. Spread the threads apart with a screwdriver to keep from wrecking the fragile alloy. In my experience, very few of these will come apart without damaging the threads.

Wow, good tip! I have to do this chore soon and hadn't thought of that one.. Thanks.

Stevo · #6 02-19-2008, 11:39 AM

You folks that don't put your location (unless your in the witness protection program or a dead beat dad) my be missing out on help, someone near by may have the part you need if he knew you were a "neighbor". Just a thought

rs899 · #7 02-19-2008, 11:49 AM

Quote:

Quote:
Originally Posted by rs899 View Post
Pick n pull is your answer. When you get one- cut the hoses with a knife. Put it on your bench and hacksaw or dremel across the nuts. Spread the threads apart with a screwdriver to keep from wrecking the fragile alloy. In my experience, very few of these will come apart without damaging the threads.
Wow, good tip! I have to do this chore soon and hadn't thought of that one.. Thanks.

This approach is not without peril, either. If you cut too deeply across the nuts you could damage the seating bevel or even cut through the alloy entirely. If you nick the threads a bit, that's Ok. The sealing is done inside the bore of the outlet, not the threads.

Rick

t walgamuth · #8 02-19-2008, 07:05 AM

The oil coolers are extremely fragile. I would not attempt the cutting and tapping of one myself and I am an advanced hobbiest. I would recommend getting a good used cooler. be sure to use the second wrench when installing or removing lines on the cooler as you will twist off the fitting and ruin it in a heartbeat if you don't.

Tom W

Eric Eliel · #9 02-19-2008, 10:12 AM

James,

I have a spare oil cooler, it appears in very good shape. I haven't used it.
Contact me off list and we can discuss. I can ship, its not a heavy item.

jamesNB · #10 02-19-2008, 09:27 PM

Thanks for the suggestions. I live near San Antonio and there is a PICK-N-PULL but I don't think there would be many MB there but it might be worth a look. Maybe next time I'm in Houston or Dallas I'll back a parts grab. I'm going to try to find a used one and get it going. Then I'll try to fix the other one as a spare.
Eric, PM send
Charmalu, thanks for the link
Stevo, I updated my profile just for you.

turbobenz · #11 05-10-2009, 09:14 PM

In my experience these fittings are pretty robust. I just take a wrench and rip em open without using two wrenches since i can never find the right wrench. I think the problem stems from people being impatient and rushing the threads back on.

cmbdiesel · #12 05-10-2009, 09:39 PM

Quote:

Originally Posted by turbobenz

In my experience these fittings are pretty robust. I just take a wrench and rip em open without using two wrenches since i can never find the right wrench. I think the problem stems from people being impatient and rushing the threads back on.

I have taken two oil cooler lines off, one took all the threads from the cooler, one didn't. My lines need changing, as they both weep, so I will do that job when I have the used replacement cooler right at hand.

pawoSD · #13 05-10-2009, 09:30 PM

I have an oil cooler I could sell if needed, just PM me if interested. I have a couple good condition spares.

Diesel911 · #14 05-11-2009, 01:26 AM

When I remove the Upper Oil Cooler Hose nut a piece of the threads from the Oil Cooler got stuck in the Threads of the Nut and ruined about 3 threads as I backed the Nut Off. I was not rushing the job and it did not feel like it was that hard to turn off either.
But, the wrench I used was a big full sized combination wrench; not the cut down one recommended so I had a lot of leverage.
I only removed the upper hose connection as my plan was to only change the rubber part of the Hose and I needed that upper section of the tubing to get a measurements from to determine what size hose I needed.
In my case I had enough good threads left that I degreased everthing and coated the Oil Cooler Threads with JB Weld and installed the tubing and tightend down the nut (remember I can change my hose now without unscrewing any of the tubings).
I have been driving over a year now with no prblems with the hose or the JB Weld repair.

However, I have aquired the Tap and Drill to install a Repair Nipple at a later Date.
Since I have read that the Repair Nipples are the same Nipples that are on the Oil Filter housing; if they can be removed easily I plan to get some at the Junk Yard and use them for my repair.

Fuzzball · #15 05-10-2010, 06:09 PM

Would Teflon plumbing tape be a reasonable sealer for these connections or would it have a problem with the temperature?