Water Pump Surgery on a 94

[firenexx]

Hi folks, I'm driving a '94 Mazda B4000 4.0L V6 with 167k miles. Manual, w/ broken A/C.

My cooling system is pretty screwed up. The radiator is leaking intermittently, I think something else is leaking coolant (not sure what yet) and the fan clutch tends to function incorrectly after about 30 minutes of highway driving, leading to overheating. Right now I'm losing coolant at an annoying rate.
I have a new radiator and upper/lower hoses coming in the mail. I have a new fan clutch that I attempted to install, but I had a little issue: Manual says thread is LH, shroud says RH. Since I'm stupid, I decided to go with the manual (before you say anything, remember, I admitted stupidity as the cause.) And well you know how those things go. Now I have a hopelessly stripped fan clutch bolt, and it's such a low clearance area that I can't seem to figure out any way to loosen it. Nothing fits in there except the tool that stripped it.

I don't really want to go somewhere and pay some dude a couple hundred bucks to fix it. So here's my crazy idea: For far less than what I'd pay for labor, I could buy a brand new or reman. water pump. I could remove the water pump/clutch/fan assembly all in one piece. Then I could slice and dice the water pump off of the clutch and remove the fan. Reassemble with new parts and I will live happily ever after.

So am I missing something? The manual says to remove the fan/clutch before removing the water pump, but perhaps this is just for convenience/ease. It looks like all 12 bolts could be accessed and removed with the fan still on there. It would be tight but I think I can make it happen. Is there some obvious thing that I'm missing, or has anyone tried this sort of thing before and found out that all the bolts are in fact not accessible with the fan still on? Any wise guidance would be much appreciated.

 

[BRUTUS_T_HOG]

yes i've been in the same situation and removed the fan/water pump as an assembly. it can be done.

its easier if you remove the radiator before you try it or you'll have to fight with pulling the fan shroud out as you pull the water pump

 

[calypso93]

I've gotten the pump/fan assembly off my 93 4L in one piece. Then I welded the impeller to the housing, stuck it in a big vise, and it was much easier to get the clutch off. Like B_T_H said, get the radiator and shroud out of the way.

 

[tobyduck]

YES!! Had to do exactly the same thing!!! The shroud can be unscrewed from the radiator, let it rest by the water pump..open up your drain and let the coolant out..take the tubing off from the radiator (to the water pump {easier}) and from the block to the radiator shouldn't be a problem. Then you can take the radiator out, take the shroud off and take the water pump off with the fan clutch still on it. I had to take a saws-all to get the aluminum off the water pump and beat the bearings out with a hammer and tough screwdriver..as for putting the thing in the vise, I had to weld a bead on the shaft (be patient with this, and don't aid in cooling it down otherwise the bead will break off)..I ended up switching from a pair of vise grips to a pipe wrench with a good set of teeth lol but as to why it is put on so tight? no clue

But my waterpump gave out and that's not what your problem is, but I still got the clutch off

 

[bronco_lou]

but as to why it is put on so tight? no clue

It not that it is put on tight, every time the engine runs and the fan clutch engages it like an impact hammer making it tighter. I put mine on finger tight and ran the engine 4 times in my driveway, just from that I had to get my trusty strap clamp out to remove the fan.

Louis

 

[tobyduck]

yea, i know over the years that is what happened. Auto manufactors make em' like that so it doesn't send the fan clutch through the radiator lol

 

[Big Jim M]

I've never had a problem taking one off.. The first thing I do is put a wrench on the fan nut and tap it with a BFH, it comes loose and then I start taking the belt and whatever else I need off.. However with the belt off it can be a real bitch, can't it.
Big JIm

 

[firenexx]

Too bad I was turning it in the wrong direction. I blame the haynes manual for that!

But anyways, thanks everyone for the input. I ended up doing it and it worked great. Of course, I didn't realize how hard it would be to get the fan off and ended up cutting my old water pump into pieces with an angle grinder to get it off so I could remove the fan. Oh well. I now have a brand new cooling system.

Strange thing - I coated the water pump bolts with anti-seize and tightened them, but once some of them got past a certain tightness, they felt like the threads broke or something and I could turn them almost freely. The rest I didn't tighten up to that point because I was worried - but does this mean the bolts were too short or something? I can't really figure it out.