91 7.3 V-Belt water pump procedures?

crowmeyocks

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Searching has been a mixed bag—mostly running into serpentine instructions. Does anyone have a link for a thorough water pump replacement procedure for a 91 V-belt? Are both the big fan clutch nut and pulley bolts LHT? I’m a bit confused there. Mostly wondering what all accessories I have to remove, alternator tension arm and AC / power steering plate both look bolted right on to the WP. Are my fears justified? Do I have to tear all that down? Thanks, I’m sure this is all well tread territory—a link would be great.
 

snicklas

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OK. I just did this earlier this spring on my 88 C-6. The only Left Handed Thread you will encounter on this is the large 30+mm "nut" on the fan clutch itself. For me, this was the worst part of this repair was getting the clutch loose. Having a helper was almost a must for me to get it loose and tight again.

For me, I removed the fan clutch, the fan shroud, the brackets that holds the power steering pump, and A/C Compressor on the drivers side. I just moved the pumps to the side, I didn't disconnect the lies to the pumps. Had to remove the brackets that was the adjuster for the alternator. The vacuum pump and alternator stayed mounted, just pushed to the side. Just to be safe, I laid the new water pump on the work bench and as I removed each fastener, I put it in the same hole in the new pump, so the same bolt came out of, and was returned to the same hole. My new pump cam with 2 new top bolts, which I used. The upper boss on some pumps is thicker/thinner, so they supply the correct length of bolt so you don't get the bolt into the timing gears. Once I had the old pump out, I moved the bolts back to the old one, in the same holes to keep them in the same position.

I also bought two 5/16 studs a couple inches long (or bolts and cut the head off) and thread them into the top two center bolt holes to act as guide pins. if you haven't changed an IDI water pump, they are surprisingly heavy, like several pounds heavy. I put just a very thin layer of schmoo (RTV) on the gasket, and slid the gasket, and then the pump on the guide studs. Threaded all but the two top fasteners into their holes, making sure to put the mounts back in where they went. Once I had all the bolts finger tight, I removed the studs and replaced them with the supplied bolts. Make sure to put schmoo on these two bolts, and the bottom two middle ones (when you have the pump off, it's really clear which four bolts) that pass through the timing cover into the oily side and will leak if they aren't sealed.

Put everything back in the reverse order. For me being a first time on an IDI (I've done water pumps on other engines before) it took 4 or 5 hours, just working through, not rushing. The most time consuming was getting the clutch loose (had to run back to the part store for additional tools)
 

IDIBRONCO

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A couple more things to add. 1) always start the fan back on the new water pump "on the bench". If not, start it before putting the fan shroud and top hose back in place. Sometimes there is an imperfection on the threads that makes it next to impossible to get the fan started on the threads straight while everything's in place. Just go on 3 or 4 threads. That will be enough.
2) I also recommend taking a flat file and gently running it across the mounting surface of the new water pump. There can be burrs on the mounting surface. I did have one that leaked after I put it on so I had to take it off. I now do this every time before installing a new pump. You don't have to push hard, just hard enough to remove the burrs that could be on there. Also, you don't want to remove any metal from the mounting surface. You're just trying to smooth it up just in case.
 

crowmeyocks

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Excellent tips everyone, thanks so much for that write up snicklas! Some poor guy in the future will be glad he found this thread. Exactly what I needed. It’s one of those times where if I start this project and don’t have what I need, I’ll be taking the bus back and forth to the parts store ha. Which is likely. Couldn’t appreciate your help more!
 

crowmeyocks

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Just one more question—for the four bolts that contact oil, can I use the permatex WP gasket goop or blue locktite or do I need some third kind of magic sludge?
 

IDIBRONCO

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Most use black rtv. I wouldn't use loctite.

Sent from my SM-N960U using Tapatalk
X2. Plus there's no "can contact oil". They will contact oil. It gets slung from your timing gears all over the back of the front engine cover that the water pump sits against.
 

PROFG

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What worked better, for me, an hour ago was put extra tension on belt with breaker and smack wrench with 2' 2x4. No glancing off metal to metal plus 2x4 was handy :D. Now to split shroud, I think, and order a clutch (no obvious means to split and fill). Still undecided on cross pinning the hub on new clutch.
 

Kizer

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Leave all your belts tight and smack the wrench on the fan clutch nut with a sledge hammer

I bought the $100 NAPA wrench / tool for fan clutch removal a few years ago. I've used it on 4 trucks now ... well worth it, in my book. You may be able to rent it from the parts house.

Also, I've used a "dead blow" hammer, on the wrench, with great results.
 

IDIBRONCO

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I've only tried to use one set of the "proper" wrenches and I HATED those things! The one for the fan nut was fine, but I feel that the one for the pulley wasn't made right. It was made flat and I couldn't get it to hook over the bolts good enough it to hold while I was turning the nut. I feel that this wrench should have been made with a little offset so that it could grip the bolts better. Of course, I may have been a dumb kid at the time and couldn't figure out how to use the wrenches the right way.
 

PROFG

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Took clutch off 5 times in last 3 days then took tools back to Oreillys (since only 48hr rental ea time). Got identical set from Autozone since could have for 90 days but could not get them to work. Turns out previous user had either turned wrong way or his nut was Locktite red since worn tool would only round off the nut:eek: I had used Locktite blue figuring it would not have to come off. Also, the most common wrench for this is 48mm but nut is actually 1-7/8" which is somewhat smaller. To hold the fork wrench on the WP nuts, push some foam pipe insulation between clutch and tool. HF 18" crescent for $20 opens just enough, tied down handle to tie rod and Bob's your Uncle. If renting the set check for wear on the 48mm wrench or just use Crescent. Pictures on request.
 
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