Author Topic: M110 coolant system fitting rusted away  (Read 242 times)

Seb

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M110 coolant system fitting rusted away
« on: 30 October 2021, 06:28 AM »
Hi friends,
On the M110 engine, there is a pressed fitting (I think it is pressed into the block) under/between cylinders 5 & 6 intake where the coolant flows from the block, through a hose and to a fitting that leads into the cabin. Please see the slightly rusted round thingy in the middle of the attached photo (from my parts car). On my actual car, this piece is completely rusted away, there is only a small rest left that a hose will never attach to.
The only solution to this problem I can think of is removing the intake manifold, drilling the rest of the rusted fitting out and pressing a new fitting. For this maybe the engine needs to be removed.
Do you have any other ideas?
Thank you!

Seb

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Re: M110 coolant system fitting rusted away
« Reply #1 on: 30 October 2021, 06:47 AM »
Let me correct myself: the piece is in the head, not the block

daantjie

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Re: M110 coolant system fitting rusted away
« Reply #2 on: 30 October 2021, 07:40 AM »
Is there enough left to attach a new sleeve over the nub that's left?  You can try JB Weld, not sure if it'll hold but that stuff can sometimes work wonders.
Daniel
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rumb

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Re: M110 coolant system fitting rusted away
« Reply #3 on: 30 October 2021, 04:25 PM »
Maybe sleeve it with a slightly bigger pipe and jb weld together, or the old one might be brazed shut the holes?
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Seb

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Re: M110 coolant system fitting rusted away
« Reply #4 on: 30 October 2021, 08:07 PM »
Thanks guys but there is not enough “meat” left to put anything on it. I think the head needs to come off  :'(

Randys01

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Re: M110 coolant system fitting rusted away
« Reply #5 on: 31 October 2021, 12:52 AM »
I'd like to see what's left of the job to be done but removing the head just for this would be the last resort.

I don't know how accessible it is but I'd be calling Captain Thread or equivalent,.

UTn_boy

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Re: M110 coolant system fitting rusted away
« Reply #6 on: 31 October 2021, 01:12 AM »
There are two versions of this connector used.  Up to a certain engine number and from a certain engine number.  Consequently, you need to post your engine number.  In addition, we need to know of you have a D-Jetronic M-110 or a K-Jetronic M-110.  The information you give in your post and profile doesn't tell us anything except that you have an M-110 engine. 

Both versions of this connector show to screw in, not press in.  That may or may not help you. 
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Seb

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Re: M110 coolant system fitting rusted away
« Reply #7 on: 31 October 2021, 06:31 AM »
I'd like to see what's left of the job to be done but removing the head just for this would be the last resort.

I don't know how accessible it is but I'd be calling Captain Thread or equivalent,.

This is what is left. Sorry for the blurry picture but I can’t get to the location any better.
To get to the fitting I’ll have to remove the intake manifold

Seb

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Re: M110 coolant system fitting rusted away
« Reply #8 on: 31 October 2021, 06:48 AM »
There are two versions of this connector used.  Up to a certain engine number and from a certain engine number.  Consequently, you need to post your engine number.  In addition, we need to know of you have a D-Jetronic M-110 or a K-Jetronic M-110.  The information you give in your post and profile doesn't tell us anything except that you have an M-110 engine. 

Both versions of this connector show to screw in, not press in.  That may or may not help you.

Thanks for the reply. I’m surprised that they screw in because I put a pipe wrench on the fitting of my donor car and couldn’t get it out.
By the way I have a 1977 K-Jet M110. Not sure where the engine number is but the cars serial number is 105518.

rumb

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Re: M110 coolant system fitting rusted away
« Reply #9 on: 31 October 2021, 09:43 AM »
With dissimilar metals the 2 parts are likely corroded/bonded together and will require some careful machining to get out and restore the threads. It would help to have a new tube on hand. Who knows what the thread size will be and if a machine shop even has a tap that size?

Alternately you could drill it out and run some pipe threads in and then use a short piece of pipe. This may still be a machine shop operation.
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Seb

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Re: M110 coolant system fitting rusted away
« Reply #10 on: 02 November 2021, 04:11 AM »
Quick update on my dilemma:
I removed the intake manifold and a bunch of other things to get access to the fitting. I cleaned it up a bit with a wire wheel and there is enough material left to cut a thread into I’d say. Now I need to find somebody that can do that.

Randys01

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Re: M110 coolant system fitting rusted away
« Reply #11 on: 06 November 2021, 08:54 PM »
Call for Captain Thread!.....or what ever your local equiv is.