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Grand Caravan Water Pump Bolt

edited November -1 in Repair and Maintenance
1997 Grand Caravan 3.3 ltr V6 engine; 105K miles.



I was about to get my water pump replaced when my mechanic informed me that one of the 5 bolts has corroded. He said he couldn't guaranty that it won't break if he tried to remove it. I thought it is too risky and decided not to proceed with the job for now until I can get more info. Does anyone have any similar experience on a caravan? What has been the result? I would appreciate your advice on whether I should proceed with the repair. Thanks



Comments

  • edited March 2011
    I assume your water pump is leaking? Or are you replacing it for some other reason?

    Anyway, assuming that the water pump needs to be replaced, then there's no choice but to remove it. If there's enough rust there that one of the bolts may break upon removal, so be it. If they all come out, great! If one or more breaks, then that's the way it goes. Your mechanic will then drill out and repair the hole using a thread insert (commonly called "Heli-Coil") and give you a bill for the additional time and materials. That additional charge if something does break shouldn't be that much, there's enough room in there for a guy to get a short bit and a 90-degree drill to the offending bolt.
  • edited March 2011
    It's a coin flip unfortunately and a sad fact of mechanical life that bolts (especially ones involved with the cooling system) may freeze in place and break off during removal.

    If the water pump has failed then you have no choice but to proceed with the process and repair the damage as necessary with one exception.
    That would be dependent upon the full story about the water pump replacement. If the pump failed and the engine was severely overheated and frying like bacon in a cast iron skillet then maybe a further examination of the engine would be necessary before replacing the pump.
  • edited March 2011

    Been-there-done-that...

    But if it needs to be done...not much of a choice...And there's no way you can get any penetrating oil in there either.

    If it breaks..then it'll have to be removed...and maybe the hole retapped.
  • edited March 2011
    When I run into a situation such as this I prepare for the worst. If the bolt snaps off, I weld a nut to the broken bolt and turn it out. http://www.youtube.com/watch?v=4BFUfGKU_ts&feature=related

    Tester
  • edited March 2011
    I have done this pump on the exact same van. The bolts in question are M6 high strength and are threaded into an aluminum pump housing. I used a significant amount of heat to heat the area around the bolts to break them free. I was able to get all but one out. The one that snapped was at the bottom of the pump housing, so it was easier to get at. I was able to drill out the bolt with a right-angle drill adapter. I then drilled the hole out for an M6 Hela-coill. All the other threads had to be chased with a tap to clean them up. I replaced all the bolts with studs because I knew I would be changing this pump again in another 100k miles. Sure enough, at 200k it needed another pump. It was a breeze with the studs in place because I just had to remove the nuts from the studs.
  • edited March 2011
    Thank you all for your input. I guess I need to take my chances. I'll get the water pump replaced and hope for the best. The water pump has a small leak and my quick fix has been to add coolant in the reservoir regularly (every 500 miles). I was told that it could get worse anytime (like when I'm out of town) and could damage my engine. So far, my engine has not over-heated yet. In that sense I'm still lucky.
  • edited March 2011
    What I find strange about this story - especially on a vehicle this old - is that there's almost no such thing as any repair where one could "guarantee" that a bolt won't break or otherwise be mangled. Its a routine part of auto repair, and mechanics routinely deal with it. I'm wondering a little bit about your mechanic.
  • edited March 2011
    That leak means coolant is coming out the weep hole, which means the inner shaft seal is gone. If you keep driving it like this the bearing will blow and you will loose all the coolant VERY fast. The serp. belt will also come off once the bearing goes. I know, becuase that's what happened to ours the first time it went:) I ignored the leak for too long.
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