Stubborn coolant tube elbow

[wwheeler]

HELP!

I am trying to remove the coolant tube elbow on the rear of my M130 cylinder head that goes to heater core. So far I have tried WD-40 and then heating, and also PB blaster followed by heat. NO luck.

The flats of the 36mm fitting are already too far gone for an open end wrench. I am going to start using a pipe wrench but want to see if any one has some good advice.

[glenn]

Heat on an aluminium head???

[SteveK]

Wallace, I've used Blaster many times and to get it to work you need to let it soak for a long time.  I typically will spray the area every night for a week before I try to break something free.   The longer the soak time the more likely it will work its way through.   Good luck!

[lurtch]

Hello Wallace - -

      I had the same problem a couple years ago on my M130 head .  I have decades  of experience in the mechanical trades and I finally threw in the towel after trying every trick in the book.

I had to purchase one from Classic Center for  $ 152.20.  I think the problem occurs because the threaded body extends too far into the coolant channel and subsequently the exposed threads begin to corrode. Once it is fused in  like that it will NOT come out no matter what you do.

Good Luck with whatever comes next - - Larry in CA

[wwheeler]

The fitting never gets very hot, like maybe 120 F. The PB blaster does seem to cling to the part where WD-40 just evaporated. I started spraying PB everyday since last Saturday and like Steve suggested, I will let it soak until this Saturday and try again. I have a good feeling this extended soak may work. But if it doesn't, I'll just leave it on and paint it to cover up the messed up flats. I have a new elbow that I would just love to put on, but I have to get the old one off first.

The other problem with this fitting is that it is soft and has a very narrow hex flats! If the flats were twice as thick, I could get a better bite. Frustrating!

[waqas]

The other problem with this fitting is that it is soft and has a very narrow hex flats! If the flats were twice as thick, I could get a better bite. Frustrating!

Could it be possible to use the closed [box] end of a large wrench [spanner] ?  You can slide it down along the elbow from the open end of the elbow.  And a cheater pipe is always useful.

Also, might be a good idea to use some anti-sieze on the threads before re-installation. (however, the exposed threads on the inside would still be susceptible to corrosion once the coolant has washed off the antisieze from there).

[pagoden]

Hello, Wallace - I don't know this fitting like you do by now, but I did learn from other soft German fasteners years ago to, yes, soak with solvents - - and to shock the parts with hammer & broad-faced punch at various times during all that soaking. 

And sometimes German Judo helps, sometimes not; apply your turning force clockwise, so that you're not fighting that corrosion buildup on the inside of the threaded section.  Ideally, it will give you just that little bit of 'wiggle room' needed to begin Phase Two of your current character-building exercise.  This used to work well with fasteners that had corroded in their original factory-assembled positions and would just twist off about 9 times out of 10 if approached counter-clockwise.

And then if it still won't listen to reason, you might saw it off back to the flats or so, then use a large dullish cold steel chisel applied to that "soft" fitting parallel to the bore in order to collapse it, pulling much of the threaded portion away from its mate in the head.  You want to break it inward rather than cut it, so that the break carries into and through the threaded portion in the head.  That ought to show it who's boss. 

OK, wise heads of the forum: will the head itself stand up to such treatment of this fitting?

Denny

[DavidBrough]

Hi Wallace,

I had the same problem a couple of years ago and had to cut the elbow to remove the nut with a socket, I then had the elbow welded back together and all is now fine. Good luck.

[wwheeler]

I was too chicken at first to cut the tube and use a socket in case I couldn't get the fitting off. Now the flats are messed up enough that a socket won't work.

I like the German Judo technique! I will try the flat punch on the face of the fitting and give it a bump clockwise. I think along with the PB Blaster and a little heat, that might loosen it up.  I am afraid to use an extension wrench because I don't want to shear the fitting (point of no return). I will definitely use anti-seize as Waqas suggested. 

Thanks again for the excellent suggestions. Oh well, back to the PB Blaster.

[glenn]

WW, I've had some success with dry ice(-70?) shrinking the inner member of the frozen pair.  Have the outer member uniformly heated.  Have the head in the sun or hot water.   Can get at least 200 degrees delta.  Put a six point box end on the fitting.   Some supermarkets have dry ice at a buck or so a pound.  Don't transport it in a closed car-CO2 will kill you.
Anything helps.

[wwheeler]

SUCCESS!

Funny how something as "simple" as removing a coolant elbow can make your entire weekend.

I did the "German Judo" technique. After that, I went clockwise on the fitting but did not notice any thing significant. Next I tried to loosen it counterclockwise with the 14" pipe wrench with no luck. I made the decision to go ahead and use an extension pipe noting that the fitting was so soft the the pipe wrench jaw made very deep impressions in it. With these deep impressions, I knew that the wrench probably wouldn't slip and more likely would first shear the hex flats from the threads in the head. While this sounds deadly, again the fitting is so soft that you should be able to use a chisel to collapse the threads inwardly and then remove with minimal damage.   

While I am not entirely sure what or what combination did the trick, I think the week long PB Blaster assault was the most effective. When the fitting was removed, there was penetrant all over the threads. Threads were not corroded and in fact, looked brand new as did the threads in the head. Not sure why it stuck.

Anyway, it is out and my new part is awaiting installation! Thanks for all of the help.