Author Topic: Water pump Housing bolt repair  (Read 2167 times)

230slhouston

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Water pump Housing bolt repair
« on: July 08, 2019, 00:51:05 »
Hi All,
I am taking my engine apart to get it ready for repair. A bolt holding the water pump housing broke in the housing. Any suggestion or ideas on how to repair this?

Thanks,
Maistran

Shvegel

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Re: Water pump Housing bolt repair
« Reply #1 on: July 08, 2019, 01:38:41 »
Always tough but doable.  If you are handy you can flatten the top with a file then drill it with a very small bit then gradually working up.  I start small so I can steer the bit into the exact center by leaning the drill and driving it to the center if the hole is off center then finish with a tap.   If you are not handy any automotive machine shop does this a hundred times a year.

Benz Dr.

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Re: Water pump Housing bolt repair
« Reply #2 on: July 08, 2019, 02:27:55 »
Looks like there's still a bit sticking out from the broken screw. If you have enough that you can fix a set of vice grips on what's left you have a good chance of being able to remove it. The trick is to use heat on the broken screw. Heat it until it starts to smoke when you pull the flame away and then try to turn it with the vice grips. If it doesn't turn don't force it. Keep applying heat until it comes loose.
If it gets crewed up to the point that you can no longer get a hold of the screw then you will need to grind it off nearly smooth with the pump flange surface and carefully drill it out. Use thread sealer on the new screws when you put it back together.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
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1967 250SL
1970 280SL
1988 560SEC

wwheeler

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Re: Water pump Housing bolt repair
« Reply #3 on: July 08, 2019, 02:52:31 »
Worse case scenario - I believe those housings are still available. Might check the price first and that may determine how aggressive you can be getting rid of the bolt.   
Wallace
Texas
'68 280SE W111 coupe
'60 220SE W128 coupe
'70 Plymouth Roadrunner 440+6

Bonnyboy

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Re: Water pump Housing bolt repair
« Reply #4 on: July 08, 2019, 04:05:38 »
I have recently been playing with outboard boat motors that were run in salt water and broken bolts are even more common than my Triumph motorcycles (which I have since sold). 

I would do what Benz Dr. said with the addition of spraying a bit of "Freeze Off" on the just the bolt itself when nice and hot (smoking) - and then carefully trying with the vicegrips,  just don't use too much heat like Oxy-Acetelyne or even just acetylene as you may bugger up the housing.  If you are quick an ice cube may work but you need to be quick so having the vice grips attached and spraying just the bolt is quicker - just don't force anything - if it wants to come out it will come out easily.

I bought a can of the Freeze Off from the local auto supply store and I swear by the stuff now - results have been amazing

Another thing to try is a backwards drillbit that when you drill into the bolt (after flattening and and drilling a small pilot hole) it is putting backwards pressure on the broken bolt and many times that is enough to get it out.   Hard to find these so try your auto supply or somebody like Acklands.  Harbor Freight may just tell you they don't exist.

If you do get to the stage of an easy-out, stay away from the spiral ones as I have had no luck with those - they break off in the holes and then its a real pain - the tapered rods with a groove on one side work the best after trying the backwards drill bit and first vicegrip, moderate heat and freeze off. 
Ian
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Benz Dr.

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Re: Water pump Housing bolt repair
« Reply #5 on: July 08, 2019, 04:13:19 »
Belay those instructions I just gave you. That casting is junk. Look at how corroded it is. The water pump impeller sits very close to the area inside the milled housing and that much corrosion won't make it work any better.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

ja17

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Re: Water pump Housing bolt repair
« Reply #6 on: July 08, 2019, 04:16:11 »
If you have a welder, just drop an oversize nut over the stud, and weld the nut to the stud, then just turn it out. The heat from the welding will assist in loosening stud so it will turn.
Joe Alexander
Blacklick, Ohio
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2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
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1974 450SLC Rally
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ja17

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Re: Water pump Housing bolt repair
« Reply #7 on: July 08, 2019, 04:18:50 »
Ditto on Dan's comment. The rough condition of the casting can cause bad circulation and over-heating if bad enough.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Benz Dr.

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Re: Water pump Housing bolt repair
« Reply #8 on: July 08, 2019, 11:56:37 »
That's the worst I've ever seen, and that would be quite a few. Makes me wonder what the head looks like.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

wwheeler

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Re: Water pump Housing bolt repair
« Reply #9 on: July 09, 2019, 00:23:58 »
That's kind of why I suggested researching a new housing. Yes, I agree a cooling system check is in order. Look at all aluminum pieces. If they are all corroded, better look at the head. What kind of coolant was used here?
Wallace
Texas
'68 280SE W111 coupe
'60 220SE W128 coupe
'70 Plymouth Roadrunner 440+6

Benz Dr.

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Re: Water pump Housing bolt repair
« Reply #10 on: July 09, 2019, 02:41:19 »
I hope not just plain water.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

230slhouston

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Re: Water pump Housing bolt repair
« Reply #11 on: August 07, 2019, 04:04:59 »
Thanks for the replies. I will look at the head and share pictures. Hope i do not have a bigger problem.

Benz Dr.

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Re: Water pump Housing bolt repair
« Reply #12 on: August 07, 2019, 04:25:55 »
Well, neither do we hope you have bigger problems.  The thing about areas that never freeze in the winter is the fact that some owners tended to cheap out and just use water as coolant. While it will work there's plenty of reasons why you should never do that. 
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

specracer

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Re: Water pump Housing bolt repair
« Reply #13 on: August 07, 2019, 10:37:32 »
Ill add this as an FYI, I have an oxy-acetelyne torch but about 6 months ago, I picked up one of these. As long at the fastener isnt too large ~ <1" (smaller induction unit doesn't quite make enough heat), this is a great tool. Its quick, compact, and the best part, you don't have to be concerned where the excess flame goes (burning / melting anything in the general area). Even used it on rusty brake lines.

http://www.theinductor.com/induction-heating-products/mini-ductor/models/md-venom