DaveC6970 Posted July 26, 2014 Share Posted July 26, 2014 Now that vacation is over I am about to tackle the dreaded water pump replacement on my 401. I've read all the threads about breaking bolts and I'm preparing for the worst but hoping for the best. There are few other things that I was thinking I should do while I'm changing the pump, but thought I might ask you guys what you thought.1. The service manual says to drain the radiator, I was thinking since the radiator was drained it might be a good time to go ahead and have it cleaned and tested. Also might it make the water pump removal easier?2. Since I've drained the system, replacing all the coolant hoses should be a must especially since I have no idea of their age.3. Cooling system flush, should I do this before I install the new hoses?4. Replace the thermostat while I'm at it.Is there anything else I should consider while I have it apart?As always any advice is appreciated, Dave Link to comment Share on other sites More sharing options...
JanZverina Posted July 26, 2014 Share Posted July 26, 2014 It's all about the bolt removal and possible breakage, so heat and a gentle touch. If you need a good rebuilder, I've used "The Flying Dutchman" in OR. He does a high quality rebuild and knows his stuff. http://water-pump-rebuilders.com/ Link to comment Share on other sites More sharing options...
RivNut Posted July 27, 2014 Share Posted July 27, 2014 If you really want to get the block cleaned and drained, there are two drains at the bottom level of the water jacket. There on the side of the block in the middle about where you'd think the water jacket should end. If you have the pump and front cover off, you might look to see if there's a step between the bottom of the water jacket and where the water goes into the block. If there's a step, you'll never get the last of the cruddy water out. Link to comment Share on other sites More sharing options...
arnulfo de l.a. Posted July 28, 2014 Share Posted July 28, 2014 I would take the timing chain cover off and check the condition of the chain and gears.also, use anti seize on every bolt when you reassembleSuerte,Arnulfo Link to comment Share on other sites More sharing options...
rocky5517 Posted July 28, 2014 Share Posted July 28, 2014 On my 67 we did the timing chain, fan clutch, rebuilt the radiator, and, while the mechanic was busy doing this I did some painting and detailing at those hard to reach places on the engine. Painted the shroud, fan, and everyrthing else I could reach. He also rebuilt my oil pump, PS pump, and new fuel pump. Ill try to post pix. And he made it clear to use distilled water when replacing the anti freeze. Im lucky to have a good friend who's also an instructor for GM and loves old cars. Link to comment Share on other sites More sharing options...
rocky5517 Posted July 28, 2014 Share Posted July 28, 2014 Dave- hope these pix help/ you'll see a before and after, and it wasn't that hard to do when all the components from the front of the engine are off. You'll see those alum brackets that hold the A/C and PS; I thought they were black until we scraped all the gunk off, washed them down, bead blasted, and wiped with alcohol. I think I sprayed a clear on- don't remember. Pay close attention to the front cover; looks great, right? It ended up in the trash because I damaged it trying to pry it off. OPGI- $500. At least it included the bearings. Link to comment Share on other sites More sharing options...
DaveC6970 Posted July 29, 2014 Author Share Posted July 29, 2014 Hey guys, thanks for all the responses and the pic's Rocky.I was hoping to not pull the timing cover, but I know I may not have any choice if I break a bolt.I'll keep you all updated on my progress. -Dave Link to comment Share on other sites More sharing options...
Seafoam65 Posted July 30, 2014 Share Posted July 30, 2014 (edited) Hey guys, thanks for all the responses and the pic's Rocky.I was hoping to not pull the timing cover, but I know I may not have any choice if I break a bolt.I'll keep you all updated on my progress. -Dave Dave, you didn't mention how many miles are on the engine and whether the timing cover has everbeen off before. I just went through all of this on my 65 with 56,000 original miles. When I bought the car it hadit's original 50 year old water pump and fuel pump so I changed them both so I wouldn't have a breakdown out on the road.I had one water pump bolt break off flush in the hole of the timing cover and had a machine shop drill out the bolt and helicoil the hole.I didn't really care because I was removing the timing cover anyway to get rid of the aluminum upper gear with plastic teeth whichlikes to shuck off the teeth and fill your oil pump screen with plastic chunks and leave you stranded by the side of the road. My gear stilllooked good with no wear on the plastic teeth, but the chain was very loose on my engine. I installed new steel gears and a new chain, but the first timing chain I bought from OPGI was very loose right out of the box. I ordered a chain from another source and it went on very tight like it should. I boughtthe tight chain from Kanter in New Jersey. Three very important things about this job........make sure you tighten the harmonic balancer bolt tofactory specs when you go back with it. If you don't the balancer will fly off on you and do all sorts of damage, possibly even damaging the crankshaftnose and definitely destroying the harmonic balancer. The spec is very high, as I recall something like 250 foot pounds. Just like a Pontiac v-8, thebalancer is not a press fit and only the high torque on the bolt will hold it from coming off. Also be sure to replace the front seal while you have the cover off as it comes off from the inside of the cover, not the front. I converted my seal from rope to neoprene. Third, unless you want to replacethe thermostat housing gasket ten times trying to stop a coolant leak, don't use a gasket....use "the right stuff" silicone form a gasket from permatex.If your timing cover has a lot of miles on it, it will be pitted to hell on the inner surfaces and you will need to replace it. My cover had some pitting butnot bad enough to need replacing yet. While you have all of this apart, it would be a good time to have your alternator gone through as it is a PITA to remove it if you have a problem later. Hope this helps....Winston Edited July 30, 2014 by Seafoam65 (see edit history) Link to comment Share on other sites More sharing options...
DaveC6970 Posted July 31, 2014 Author Share Posted July 31, 2014 Hey Winston, thanks for all the info. My car has about 75K miles and as far as I know the timing cover has never been removed. It does look like the water pump may have been off before. I'm starting to think it may be worthwhile to remove the timing cover, even if I don't break any bolts, just to check the timing chain. Wonder what the thinking was at Buick to use plastic teeth on the gear? Thanks! Dave Link to comment Share on other sites More sharing options...
RivNut Posted July 31, 2014 Share Posted July 31, 2014 Before you replace the front cover, look at the ROA website for the part number for a neoprene seal to replace the old style.FYI, the pictures in post #6 are for a Buick big block (400/430/455,) not a nailhead. Link to comment Share on other sites More sharing options...
Seafoam65 Posted July 31, 2014 Share Posted July 31, 2014 Hey Winston, thanks for all the info. My car has about 75K miles and as far as I know the timing cover has never been removed. It does look like the water pump may have been off before. I'm starting to think it may be worthwhile to remove the timing cover, even if I don't break any bolts, just to check the timing chain. Wonder what the thinking was at Buick to use plastic teeth on the gear? Thanks! Dave Supposedly the plastic teeth were used to cut down on engine noise. My belief is the engineers were playing a joke on the consumer, theywere idiots or GM management made them do it as part of their planned obsolescence program. Back in the 70's I used to see them fail all the time in less than 100,000 miles. The worst part of the whole thing when they fail is you have to pull the pan and get the plastic bits out of your oil pump screenor risk ruining the engine from oil flow restriction. Link to comment Share on other sites More sharing options...
arnulfo de l.a. Posted August 2, 2014 Share Posted August 2, 2014 I would also suggest using all new grade 5 hardware when you reassemble. I tried using the original hardware when I reassembled and ended up breaking a couple when torquing. I'm anal about trying to maintain the originality of the car down to every nut, bolt ,and washer. Live and learn .... Right?arnulfo Link to comment Share on other sites More sharing options...
DaveC6970 Posted August 10, 2014 Author Share Posted August 10, 2014 Thought I would update the status of my water pump replacement. All the bolts broke loose with just a reasonable amount of effort after soaking with penetrating oil for the past week, woohoo! I'm betting that this water pump has been off before by how easily the bolts came out. Now I have the water pump loose from the timing cover but cannot remove it completely. It appears that the bracket that mounts the AC compressor and alternator is trapping the lower left bolt, circled red in the image attached. I have removed the 2 bolts directly above this that hold the bracket and crossover to the block. My question is do I have to completely remove this mounting bracket to get the water pump off? If so how big a job is that? Thanks for the help, Dave Link to comment Share on other sites More sharing options...
Lapham3 Posted August 11, 2014 Share Posted August 11, 2014 Years ago on a road trip I had to replace the water pump on my '66 cat w/AC. I got the other bracket mounting bolts out or somewhat loose and then was able to lever it over just enough with the tire iron to get the pump to clear-good luck! Link to comment Share on other sites More sharing options...
DaveC6970 Posted August 15, 2014 Author Share Posted August 15, 2014 Well, she's off! It was a bit of a pain but I was lucky it could have been worse. I did have to remove or loosen all of the bolts on the AC/Alternator bracket. The worse one is underneath the AC compressor, so you need to remove the compressor bolts and move it out of the way. It is a cylinder head bolt I believe so that's going to need torqued when it goes back. Now with the water pump off I was checking the timing cover for the pitting that I hear about. It looks pretty clean inside to me but I'm no expert, what do you guys think? pic attachedAlso, any advice on where to get a replacement? I was leaning towards Russ at nailhead.com, I would rather go to a nailhead specialist than just a parts retailer.Thanks, Dave Link to comment Share on other sites More sharing options...
Seafoam65 Posted August 15, 2014 Share Posted August 15, 2014 I don't see any pitting at all.....it looks in better shape than mine was.....looks to me like you can use the timing cover that you have. Now that you've come this far,keep going till you get to the timing chain and gears if you don't know if they have ever been changed. Also hang a new fuel pump on there while you are in there. Even if thepump that is on there has low mileage on it, pumps from a few years ago were not made with a diaphragm designed to cope with alcohol laced fuel. Link to comment Share on other sites More sharing options...
60FlatTop Posted August 15, 2014 Share Posted August 15, 2014 Around 1994 I put a new pump on my Riviera and used hardened 1/4-20 Allen screws in place of the standard cap screws, The got a liberal coat of Never-Sieze on the threads. Since then the whole works has been coated with Bill Hirsch engine paint. A can of water pump lubricant in the coolant is a standard procedure of mine.In typical machine use the black coated Allen screws tend to corrode less and the hex socket is as deep if not deeper that the original screws heads, which seem a little shallow. Seems fine so far.Bernie Link to comment Share on other sites More sharing options...
DaveC6970 Posted August 15, 2014 Author Share Posted August 15, 2014 SF, I've been debating about doing the timing chain since I already have it this far apart. Just how hard is it to get off? Is that balancer a PIA? Do I have to drop the oil pan? I know a new timing chain would be good insurance against future issues, but I have been lucky about the bolts and would hate to jinx it. Bernie, I like the idea of using cap screws, I was about to ask that very question. Thanks -Dave Link to comment Share on other sites More sharing options...
Guest Kaber Posted August 15, 2014 Share Posted August 15, 2014 I'd keep going, your almost there. Tim Link to comment Share on other sites More sharing options...
RivNut Posted August 15, 2014 Share Posted August 15, 2014 Make sure that when you put on a new pump, you install a pump for the a/c cars - five blade impeller vs. three blades for the non-a/c cars. Make sure that the impeller blades them selves haven't been "smoothed" up in a rebuild. If they've been "smoothed," there will be material missing and you won't have a tight fit of the impellers against the timing cover and you'll just cavitate water rather than moving it.If you do go for the timing chain, get one from Russ Martin or someone else that doesn't have the nylon on the gears and get a double roller chain for it.Ed Link to comment Share on other sites More sharing options...
Seafoam65 Posted August 15, 2014 Share Posted August 15, 2014 (edited) SF, I've been debating about doing the timing chain since I already have it this far apart. Just how hard is it to get off? Is that balancer a PIA? Do I have to drop the oil pan? I know a new timing chain would be good insurance against future issues, but I have been lucky about the bolts and would hate to jinx it. Bernie, I like the idea of using cap screws, I was about to ask that very question. Thanks -Dave You don't need to drop the oil pan. The balancer slides right off once you remove the balancer bolt. The hard part is going to be breaking the balancer bolt loose. Since I'm in the car repair business I had my car on a lift and one of my techs held a backup on the flywheel with a flywheel toolwhile I broke the bolt loose with a very long breaker bar. When I went back with the bolt we did it the same way except with a torque wrench on the boltwhile holding a backup on the flywheel. I don't recall the exact spec on the bolt torque but it was very high....something like 250 ft lbs. You could probablybreak it loose with a high powered impact wrench as well.....I didn't pull my radiator out so I didn't have room to get a wrench in there and do it that way.If you put anti-seize on the threads when you go back you won't have a problem in the future with seized and broken bolts. I installed my originalbolts back in the water pump with anti-seize on them. Be sure to replace the front crank seal while you have the cover off, and use the right stuff siliconesealer from permatex on the water passage holes in the timing cover gasket, and in the corners where the front oil pan gasket meets the timing cover gasket. I like Ed's suggestion of the double roller timing chain.I wanted to use one but I was unable to find anyone who had one for a nailhead engine. If there is one available I would definitely recommend using it....they are much better about not stretching. Edited August 15, 2014 by Seafoam65 (see edit history) Link to comment Share on other sites More sharing options...
steelman Posted August 15, 2014 Share Posted August 15, 2014 When you look for a replacement water pump, check out TA Performance. They have one with a bearing in place of the front bushing. Less drag, lasts a lot longer. Minor casting change to do this, but hard to tell once installed that it is any different. Link to comment Share on other sites More sharing options...
DaveC6970 Posted August 17, 2014 Author Share Posted August 17, 2014 Ok, so I agreed with the advice that I'm this far I should just keep going and removed the timing cover. As with the water pump all the bolts came loose with a little effort, none broke off. I'm pretty sure this engine has been this far apart at one time in its 74K miles. All of the bolt holes appeared to have some leftover coating around the openings. I'm thinking I was lucky in that a previous owner coated all the bolts when he reassembled. I'd like to buy that guy a beer BTW. Attached are pics of my timing chain, I cannot see any plastic/nylon but I'm not exactly sure what I'm looking for, maybe this chain has been switched out already? Is it easy to tell the plastic coated gears? It does seem to have a lot of slack in it so maybe a new chain was in order anyway. How much slack is too much?Thanks again for all the help. -Dave Link to comment Share on other sites More sharing options...
RivNut Posted August 17, 2014 Share Posted August 17, 2014 I went back and re-read my post about nylon. I confused everyone. My bad. The nylon is on the teeth of the timing gears, it's not on the chain. Your gears look to be in good shape and it appears that there's no slack in the chain. That brownish colored coating looks like the nylon that I'm familiar with. Looks like you're good to go unless you just want the added assurance. Ed Link to comment Share on other sites More sharing options...
DaveC6970 Posted August 18, 2014 Author Share Posted August 18, 2014 This chain seems loose to me. I checked the deflection/slack and with the chain tight on one side, the loose side had over 1/2 inch of movement or slack. I could not find any spec in the service manual but it seems like a lot doesn't it? -Dave Link to comment Share on other sites More sharing options...
Seafoam65 Posted August 18, 2014 Share Posted August 18, 2014 This chain seems loose to me. I checked the deflection/slack and with the chain tight on one side, the loose side had over 1/2 inch of movement or slack. I could not find any spec in the service manual but it seems like a lot doesn't it? -Dave In the picture I see an upper gear that is aluminum with yellow plastic teeth and the chain is very loose. You need to change out the upper and lower gears and the chain. When you install them be very careful that the timing marks are lined up correctly. A double roller chain is best but asI stated I never found any offered for a nailhead engine. If someone on the forum knows where the double roller setup can be sourced, go with that.Once the chain gets loose it can rip off the plastic teeth from the chain whipping around. It looks to me like you are doing this just in time. Link to comment Share on other sites More sharing options...
RivNut Posted August 18, 2014 Share Posted August 18, 2014 Well, Russ Martin used to have them on his website but now he only advertises the double roller set for the smaller nailhead - 264/322, and it's out of stock. Has anyone checked with Tom Telesco or Carmen Faso to see if either of them might have one? TA Performance has a single roller chain that they are proud of. They want more for it than for a double roller for the 400/430/455. Their ad says it's "better."Ed Link to comment Share on other sites More sharing options...
DaveC6970 Posted September 13, 2014 Author Share Posted September 13, 2014 Well, I think I have finally collected all the parts to finally finish this job. Work and life seem to have gotten in the way if you know what I mean. After talking to Russ Martin I decided, that even though my timing chain set had been replaced at some point with a non-plastic tooth version, there was too much slack in mine and it would be prudent to replace it. I went with the roller chain version he sells, not cheap but a nice part. So before I remove my old chain I would like to line up the 2 "dots" on the crank and cam gear, per the service manual. This may be a dumb question, but is there an easier way to do this other than bump the starter, which is what I was planning to do?Thanks, Dave Link to comment Share on other sites More sharing options...
RivNut Posted September 13, 2014 Share Posted September 13, 2014 You can put the crank snout bolt back in the end of the crank and use a breaker bar to turn it over. Taking out the spark plugs will take any compression out of the cylinders. Link to comment Share on other sites More sharing options...
DaveC6970 Posted September 14, 2014 Author Share Posted September 14, 2014 You can put the crank snout bolt back in the end of the crank and use a breaker bar to turn it over. Taking out the spark plugs will take any compression out of the cylinders.I was thinking of using the crank bolt but forgot about pulling the spark plugs. Thanks Ed! Link to comment Share on other sites More sharing options...
DaveC6970 Posted September 24, 2014 Author Share Posted September 24, 2014 I was thinking of assembling the water pump to the timing cover on the workbench, before bolting the timing cover back to the engine. Things are always easier on the workbench. Is there any reason I wouldn't want to do this? Thanks, Dave Link to comment Share on other sites More sharing options...
DaveC6970 Posted September 27, 2014 Author Share Posted September 27, 2014 Thought I would post an update, spent most of the last week prepping gasket surfaces. This took much longer than I expected, but finally everything is nice and clean.Installed my new roller timing chain I got from Russ Martin today. It didn't go on as easy as the old loose chain came off, this dude is tight, but a real nice piece. I looked in the manual and searched online but can't find the torque setting for the cam gear anywhere. Any ideas on what this value is or where I might find it?Also, I was thinking of using thread lock on this bolt and the crank damper bolt, good or bad idea?Thanks, Dave Link to comment Share on other sites More sharing options...
Garett Posted June 8, 2019 Share Posted June 8, 2019 (edited) This is the water block behind the water pump.What do you suggest to fix the pitting? Jb weld? haha. Does a new part replacement for this exist and if it does what is it called? Thanks, Josh and Garett Robertson Edited June 8, 2019 by Garett (see edit history) Link to comment Share on other sites More sharing options...
RivNut Posted June 8, 2019 Share Posted June 8, 2019 The new part is just called a front cover or a timing chain cover. As long as you have the timing chain covervoff, check the timing gear on the camshaft. Originally it had nylon covering the teeth to help keep things quiet. As time goes by, the nylon will break off making the engine hard to time correctly. There are reproductions ofvthe timing cover available. New cam gears are solid with no nylon. Your new pump has a five blade impeller. It came as original on air conditioned cars. It will move more water, helping cool the engine. 1 Link to comment Share on other sites More sharing options...
telriv Posted June 8, 2019 Share Posted June 8, 2019 DEFINITELY needs a NEW timing case cover WITHOUT A DOUBT!!!! Link to comment Share on other sites More sharing options...
60FlatTop Posted June 8, 2019 Share Posted June 8, 2019 Being aluminum it is already potentially porous material. The corrosion can get you closer to leak between the cooling system and the crankcase, especially under pressure. Since new covers are available it is good insurance to replace it. It is also another good reason to periodically pressure test the cooling system. I like to do the test with the engine cold and warm. Odd porosity over years, corroded core plugs, and weak hoses can go unnoticed without testing. I also hung a spare cover on the wall about 25 years ago. You can't beat having Murphy's Law on your side. Bernie Link to comment Share on other sites More sharing options...
Zimm63 Posted June 10, 2019 Share Posted June 10, 2019 Any best source for a new cover, or are they all from the same original maker these days? Link to comment Share on other sites More sharing options...
Garett Posted June 13, 2019 Share Posted June 13, 2019 Thank you everyone for the input. Just gotta fork over the $325 for the new timing cover. Was hoping to avoid it. But "best laid plans". Just will delay things a bit. Link to comment Share on other sites More sharing options...
telriv Posted June 13, 2019 Share Posted June 13, 2019 Believe me it's a quality piece. I was in on the design & fab. Tom T. Link to comment Share on other sites More sharing options...
60FlatTop Posted June 13, 2019 Share Posted June 13, 2019 The spare I have hanging on the wall has flour or five 1/4-20 Helicoils in it from repairing the broken bolts. If I had to farm that job out it would have eaten most or all of the $350. Link to comment Share on other sites More sharing options...
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