neil morse Posted March 8, 2019 Share Posted March 8, 2019 I'm having water pump issues with my '41. Can I remove the pump without taking out the radiator? I sure hope so. The shop manual is no help at all. Any assistance would be most appreciated. Link to comment Share on other sites More sharing options...
Daves1940Buick56S Posted March 8, 2019 Share Posted March 8, 2019 Yes! I have done it several times on my 1940 56s. I think I have replied on this before, gimme a few minutes to go find it. Cheers, Dave Link to comment Share on other sites More sharing options...
Daves1940Buick56S Posted March 8, 2019 Share Posted March 8, 2019 OK, nothing like what you want, so will do from scratch: 1. Drain coolant and loosen and remove fan belt 2. Remove upper rad hose and pull off water pump end of lower rad hose 3. Pull heater hoses off of pump and bypass 4. Remove thermostat cover and thermostat 5. Unbolt bypass (2 bolts, one long, one short) 6. Loosen upper clamp on bypass hose (connects to water pump) 7. Remove bypass using twisting action to break from hose 8. Cover front of radiator with a piece of cardboard to protect it and your knuckles 9. Loosen long bolt in center area of pump 10. There are 2 bolts on the pump to block connection. Remove the inner bolt and loosen the outer one 11. Holding pump by fan to keep it from flopping about, remove long center bolt (you many have to spin fan to clear) 12. Remove pump to block outer bolt, and carefully maneuver pump/fan assembly to top of engine and out Cheers, Dave 4 Link to comment Share on other sites More sharing options...
neil morse Posted March 8, 2019 Author Share Posted March 8, 2019 Thanks, Dave! Link to comment Share on other sites More sharing options...
Matt Harwood Posted March 8, 2019 Share Posted March 8, 2019 Dave's got the long and short of it. Just one other note: at least one of the bolts goes through the water jacket, so you'll need sealer on it when you reassemble (photo attached of when I pulled the pump on my '41 Century). I have a fresh water pump for my '41 Limited but the thing runs at 160 degrees without flinching, so I don't much want to take it apart even though the pump is starting to get a little noisy. Keep us posted on your job so I can feel better about going in after mine! 2 Link to comment Share on other sites More sharing options...
neil morse Posted March 8, 2019 Author Share Posted March 8, 2019 21 minutes ago, Matt Harwood said: I have a fresh water pump for my '41 Limited but the thing runs at 160 degrees without flinching, so I don't much want to take it apart even though the pump is starting to get a little noisy. Keep us posted on your job so I can feel better about going in after mine! Thanks, Matt. I will definitely keep you posted. That's interesting about that bolt that goes through the water jacket because that seems to be the general area where my pump is leaking. I can't tell until I get in there, but I have a slow leak somewhere at the bottom of the pump. I figured that the gasket may have failed there, but it may be that it's leaking from that bolt hole. Having reviewed Dave's recommended procedure and having taken a look at the clearance between the fan and the radiator (barely an inch, I would say), I now want to ask the opposite question: Is it possibly easier on the '41 just to take the radiator out? Once the hood is removed, it looks like it's actually pretty simple -- just unbolt it and pull it straight up. I did it on my '48 Chrysler and it was very easy. Getting it out of the way sure would make it easier to tackle the pump removal. Link to comment Share on other sites More sharing options...
Morgan Wright Posted March 8, 2019 Share Posted March 8, 2019 It was really easy to take out my '40 radiator once the hood was off. Except the drain cock stuck forward a few inches on mine, and hooked on something, so I had to remove the drain cock first. I replaced it with a shorter one to make it easier next time. The drain cock nut is made of brass so you have to use the box end of the wrench to avoid stripping it. Link to comment Share on other sites More sharing options...
Matt Harwood Posted March 8, 2019 Share Posted March 8, 2019 It's not a HUGE job to remove the radiator, but it's an extra step and the radiator is VERY heavy. With care you should be able to get the pump out without much effort--most of the bolts are closer to the block than to the radiator so a wrench can get in there without too much difficulty. It's just the nose of the pump that's close. The pump itself isn't very big, about the size of your hand, so maneuvering it out isn't a big deal. It's always my preference to do a job where the fewest number of things can go wrong, and that often means leaving as much as possible intact. But that's me, there's no right or wrong way to do it and if you are more comfortable with the extra space, that can make the difference between a pleasurable afternoon project and thrown wrenches. 3 Link to comment Share on other sites More sharing options...
pont35cpe Posted March 8, 2019 Share Posted March 8, 2019 (edited) Neil, I rebuilt a `41 248 for my `36 coupe. The engine had never been apart. I hope this doesn`t happen to you, but all the water pump mount bolts twisted off. flush with the head. Also all the mounting bolts had copper washers.. Edited March 8, 2019 by pont35cpe (see edit history) Link to comment Share on other sites More sharing options...
neil morse Posted March 8, 2019 Author Share Posted March 8, 2019 Okay, thanks everyone for the help. I will consult with my "assistant" 😉 Mr. Micheletti, and we will figure out which way we want to go. I like the way you summed it up, Matt! Link to comment Share on other sites More sharing options...
neil morse Posted March 8, 2019 Author Share Posted March 8, 2019 6 minutes ago, pont35cpe said: Neil, I rebuilt a `41 248 for my `36 coupe. The engine had never been apart. I hope this doesn`t happen to you, but all the water pump mount bolts twisted off. flush with the head. Yikes! That sounds like a huge drag. Talk about "thrown wrenches!" I don't have a full history on my car, but I know a lot of work was done on it in the 80's or 90's, and I'm pretty sure the water pump has been off. We shall see. Link to comment Share on other sites More sharing options...
pont35cpe Posted March 8, 2019 Share Posted March 8, 2019 Just now, neil morse said: Yikes! That sounds like a huge drag. Talk about "thrown wrenches!" I don't have a full history on my car, but I know a lot of work was done on it in the 80's or 90's, and I'm pretty sure the water pump has been off. We shall see. Yes, I did have a little fit and glad no one was here to witness it. I also used anti-seize when I put it back together. Link to comment Share on other sites More sharing options...
neil morse Posted March 20, 2019 Author Share Posted March 20, 2019 On 3/8/2019 at 1:14 PM, Matt Harwood said: Keep us posted on your job so I can feel better about going in after mine! Okay, here's the rest of the story (skipping a few twists and turns). It was very hard to tell where the leak was coming from on my car. Water was trickling down the engine block under the generator and ending up on the ground. It was not a huge leak, but enough to take probably a few quarts a week out of the cooling system. This photo shows where the water was trickling down the block. The inside of the fan pulley was completely dry, so it was clear that it wasn't a typical water pump problem where water is coming out of the relief holes at the base of the shaft of the pump. Water seemed to be collecting under the elbow joint of the pump, but I really couldn't tell because you can't see in there. But if I stuck a dry rag in there, it came out wet. So I bought a new pump ($125.00, free shipping from Cars, Inc. in New Jersey), and arranged to bring the car down to Don's house in Menlo Park where he is kind enough to assist me in all mechanical operations that I don't feel confident tackling by myself. We figured we would just replace the pump as a proactive measure which would presumably take care of the problem wherever the leak was coming from. In the meantime, I painted my new pump with a rattle can of correct Dante Red engine enamel. But then my concern for cosmetics entered into it. The thermostat/bypass housing looked terrible, and I knew there wouldn't be time to strip and repaint it when I was at Don's house, so I figured I would go ahead and remove it, strip it, and repaint it even though I would have to remove it again to do the water pump job. After this operation was complete and the housing was reinstalled with a new gasket, with the addition of a new thermostat and new hoses while I was at it, guess what? The leak has stopped! So it’s difficult to say where the coolant was leaking from, since I changed several things at once. It could have been a failed gasket in the area of the rectangular opening between the block and the housing, a leak from one of the bolts that holds the housing onto block (which both penetrate into the water jacket), from one of the hoses I changed, or the gasket on the thermostat housing. I didn’t see any obvious evidence of leaking in any of these areas when I took the housing off, but who knows? So now I have a better looking engine, and a new pump in reserve, and I’m just waiting to see what happens next. 5 Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted March 20, 2019 Share Posted March 20, 2019 I LIKE bad stories that end well! Ben 1 Link to comment Share on other sites More sharing options...
Matt Harwood Posted March 20, 2019 Share Posted March 20, 2019 Nice work, Neil. It's always a pleasant surprise when a job is easier than expected instead of a nightmare. The Dante Red matches well, too! 1 Link to comment Share on other sites More sharing options...
neil morse Posted April 1, 2019 Author Share Posted April 1, 2019 The rest of the story Well, it looks like this situation was not as easy as it appeared to be. After running with zero leakage for nearly two weeks (including an all day tour of over 100 miles), the leak is back in the same place. This is really a mystery. Now that I know where to look, I have examined the thermostat/bypass housing as carefully as I can, and I can't find any coolant coming from that area. Even though taking it off and putting it back seemed to have taken care of the problem initially. It's very odd. I've driven the car every day for the past three days, and all of a sudden I come home from running an errand this afternoon and there it is -- drip, drip, drip. So it looks like we will be pulling the water pump after all, although I damned if I can figure out how the pump has developed an intermittent leak that seems to somehow be related to the thermostat/bypass housing. Obviously, any and all opinions are welcome regarding what might be going on here! Link to comment Share on other sites More sharing options...
Daves1940Buick56S Posted April 1, 2019 Share Posted April 1, 2019 Perhaps a dumb question, but did you replace the bypass hose? Cheers, Dave 1 Link to comment Share on other sites More sharing options...
neil morse Posted April 1, 2019 Author Share Posted April 1, 2019 There are no dumb questions. Yes, I replaced the bypass hose. But there is no indication that I can see that there is any leakage from that area. Just to recap, there was leakage coming down the left side of the engine block under the generator, as shown in the photo I posted. I took off the thermostat/bypass housing, replaced the top hose, replaced the bypass hose, replaced the thermostat (and gasket), and put the housing back on with a new gasket, and the leak stopped for about two weeks. Now the leak has come back. Again, the coolant is leaking down the driver's side of the engine block under the generator, but it's very hard to figure out where it's actually coming from. Link to comment Share on other sites More sharing options...
FLYER15015 Posted April 1, 2019 Share Posted April 1, 2019 Neil, Just an idle question. How did you seal the 2 bolts holding the pump on ? Also did you do the standard bypass fix for overheating, and that is to tap in an expansion plug, and drill a 5/16ths hole in the center. That finally fixed my overheating issues on the '40 LTD. Mike in Colorado 1 Link to comment Share on other sites More sharing options...
neil morse Posted April 1, 2019 Author Share Posted April 1, 2019 There are no idle questions, either! I have not removed the pump, so I don't know anything about the bolts holding the pump on. I sealed the two bolts holding on the thermostat/bypass housing with black silicone, and used sealing washers on them. The leak is not coming from either of these bolts, as far as I can see. I did not do the "standard bypass fix for overheating." I am not experiencing any kind of overheating problem. Link to comment Share on other sites More sharing options...
FLYER15015 Posted April 1, 2019 Share Posted April 1, 2019 Neil, After fighting a severe overheating problem with my '40 LTD, and after installing 2 gallons of Evap-o-rust, for about a week, to no avail, I learned about pulling the temperature sensing spring loaded deally out of the bypass valve, tapping in an expansion plug and drilling a 5/16ths hole in the center. Supposedly this restricts the flow of water coming out of the bottom of the radiator, and creates a "venturi effect" to pull water out of the head, thus solving the overheating issue. It worked very well for me. The evap-o-rust did work so well that I had to replace the front and rear expansion plugs as they started dripping. I did get to see in the back of the water jacket and it was squeaky clean in there, but she was still running hot, till I did the bypass valve fix. Mike in Colorado 1 Link to comment Share on other sites More sharing options...
neil morse Posted April 1, 2019 Author Share Posted April 1, 2019 Hi Mike, Yes I read all about your bypass fix when I was searching for threads about water pump issues. But I am not having any kind of overheating problem. More of a "phantom leak" problem, it seems. Link to comment Share on other sites More sharing options...
Grimy Posted April 1, 2019 Share Posted April 1, 2019 Neil, try drying the area with rags and/or hair dryer, then check with "long handle" cotton swabs from drugstore. If no leak when not running, repeat cotton swab test after running long enough to get t'stat open. Link to comment Share on other sites More sharing options...
1940Super Posted April 2, 2019 Share Posted April 2, 2019 I've had the screws holding the backing plate to the pump leak before but seeing as you replaced the pump with a new one that shouldn't be the problem. Another problem area with 1940 buicks noted in a 1940 service bulletin is the inlet of the water pump having no shoulder at the end of the casting where the hose connects onto. I found the neck of the casting that sits above the thermostat housing very corroded to the point where it was a very uneven surface due to leaks over a very long time so I decided to follow the same instructions used in the service bulletin for the water pump inlet and file it round and create a small shoulder. From the photos it looks your neck is in a similar condition but I doubt it is what your leaking problem is as you would easily see it leaking from that spot. I found the bypass hose can be tricky getting clamped up tight because there is minimal clamping area. Link to comment Share on other sites More sharing options...
1940Super Posted April 2, 2019 Share Posted April 2, 2019 Before and after photos. 1 Link to comment Share on other sites More sharing options...
Dynaflash8 Posted April 2, 2019 Share Posted April 2, 2019 On 3/8/2019 at 4:45 PM, neil morse said: Thanks, Matt. I will definitely keep you posted. That's interesting about that bolt that goes through the water jacket because that seems to be the general area where my pump is leaking. I can't tell until I get in there, but I have a slow leak somewhere at the bottom of the pump. I figured that the gasket may have failed there, but it may be that it's leaking from that bolt hole. Having reviewed Dave's recommended procedure and having taken a look at the clearance between the fan and the radiator (barely an inch, I would say), I now want to ask the opposite question: Is it possibly easier on the '41 just to take the radiator out? Once the hood is removed, it looks like it's actually pretty simple -- just unbolt it and pull it straight up. I did it on my '48 Chrysler and it was very easy. Getting it out of the way sure would make it easier to tackle the pump removal. You don't want that fan shaft to come loose into the radiator. I had that happen one time on a '34 Pontiac...took out the radiator with it. Link to comment Share on other sites More sharing options...
1940Super Posted April 2, 2019 Share Posted April 2, 2019 19 hours ago, FLYER15015 said: Neil, After fighting a severe overheating problem with my '40 LTD, and after installing 2 gallons of Evap-o-rust, for about a week, to no avail, I learned about pulling the temperature sensing spring loaded deally out of the bypass valve, tapping in an expansion plug and drilling a 5/16ths hole in the center. Supposedly this restricts the flow of water coming out of the bottom of the radiator, and creates a "venturi effect" to pull water out of the head, thus solving the overheating issue. It worked very well for me. The evap-o-rust did work so well that I had to replace the front and rear expansion plugs as they started dripping. I did get to see in the back of the water jacket and it was squeaky clean in there, but she was still running hot, till I did the bypass valve fix. Mike in Colorado Perhaps this overheating issue was more a problem for the larger engines? Link to comment Share on other sites More sharing options...
neil morse Posted April 2, 2019 Author Share Posted April 2, 2019 Thank you, everybody, for your responses. I am out of town this week but I will try Grimy's diagnostic suggestion when I get back home. It's very hard to figure out what's going on here. Link to comment Share on other sites More sharing options...
Matt Harwood Posted April 2, 2019 Share Posted April 2, 2019 The system is designed to run at about 7 PSI anyway--you can buy a pressurization setup that fits on the radiator neck and will pressurize the system. If you clean up the affected areas really well, you might be able to determine where the leak is coming from without the engine running. We do it all the time on various cars and it's a very useful technique. Let us know how you proceed! Link to comment Share on other sites More sharing options...
Grimy Posted April 2, 2019 Share Posted April 2, 2019 Neil, I have the pressurization equipment Matt speaks of, and you're welcome to borrow it, or to bring the Buick over here if we ever get a dry day..... Link to comment Share on other sites More sharing options...
Daves1940Buick56S Posted April 2, 2019 Share Posted April 2, 2019 Another suggestion, get one of the LED Black Light flashlights. Use it at night or in a dark garage. The antifreeze flouresces so it can be easily seen. Just a note, though: so does oil! So make sure you know what you are looking at... Cheers, Dave Link to comment Share on other sites More sharing options...
neil morse Posted April 26, 2019 Author Share Posted April 26, 2019 (edited) The end of the story (I hope) So Don and I finally were able to schedule a time for me to bring my car down to his place and go ahead and remove and replace the pump. As the photo shows, once we got the old pump off and could get a good look at it, the stains on the pump made it clear that it was leaking in the conventional way and looks like it had been leaking on and off for some time. It's the "on and off" part that's hard to understand. Why the leak started and stopped, and seemed to do so in response to taking off and putting back the thermostat housing, will remain a mystery. As long as the problem is solved (and it seems to be), I'm a happy camper! Thanks again to all of you who chimed in with helpful comments. The job turned out to be pretty straightforward, just as Dave said it would be. Edited April 26, 2019 by neil morse (see edit history) 3 Link to comment Share on other sites More sharing options...
neil morse Posted April 27, 2019 Author Share Posted April 27, 2019 Two more photos: The obligatory "job's all done" shot showing everything back together. Bonus photo showing Don annealing one of the copper sealing washers before installation (another example of how fortunate I am to have Don's assistance since I had never even heard the term "annealing" before I learned it from Don!). 3 Link to comment Share on other sites More sharing options...
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