Since I finally have my car ready to drive after restoration and revision I noticed I have a problem with cooling at idle. It goes up to 240 to Autometer gauge. En we tried some point and shoot thermometers on it and they confirm. Ambient was 68. Freshly built (thus clean) engine. New radiator: https://www.rockauto.com/en/moreinfo.php?pk=3611613&cc=1021442&pt=2172&jsn=6 with a 190F thermostat. Taurus fan and shroud set up with BMW double temp (91C/99C) switch. (=195F/210F). That pulls a lot of air. No issues when driving, so I'm thinking my waterpump doesn't provide enough flow at idle. (Higher RPM in Park seems to confirm this, because temp does go down a little) Now I do have a 1969 GS 400, but I have a 430 engine in it, not sure, but I think a Riviera. Could my problem be there? It came with a fixed 5-blade fan, which now is replaced. In this thread (https://www.v8buick.com/index.php?threads/bbb-overheating-at-idle.311792/) I see different pulley sizes and waterpump combinations discussed. I have the 6 1/4" crankshaft pulley; 6 3/4" waterpump pulley and the 5 impeller probably original waterpump of that engine. (looks like the short type). Any thoughts? Ignition is 8* initial + manifold vacuum of the stock distributor. (recurved a little bit; stock would have been 0* and manifold vac). So definately not retarded. 1 added picture of old blade, 1 of water pump, 2 of current situation.
The water pump is under driven, that isn't helping anything. I would guess the Taurus fans are not pulling enough air either.
The electric fans should be able to keep it cool at idle I agree fans may not be strong enough, not enough cfm Or they may not be in the right spot from rad to cause air to be pulled thru rad. Obviously you have no air flow thru rad when sitting still possibly? I have the old school 7 blade and fan clutch with shroud and I would let the car sit in drive idling on a hot day to see if it would overheat and it just would not. Can you see the water flowing in rad at idle? Could be water pump and under drive pulleys if you have that. But those fans should be able to cool that off. Maybe they need to just be on anytime the engine is at idle, that may get a jump on overheating before it happens. just some thoughts
If you decide to upgrade the water pump, checkout the TA performance hi flow pump. Young Mike from TA Performance posted a comment several years ago how they redesigned their pump to solve several cavitation issues. They don’t explain this in their catalog. "Our water pump is a cast aluminum housing that we machine in house and I personally assemble. We use bearings, seals and flange that are made in America. The impeller is cast aluminum that we machine and have hard anodize coated to prevent corrosion. Our water pump casting has much larger water passages than a common pump and the casting is much thicker. Our impeller is a positive displacement type so it prevents cavitation, builds more pressure, and flows much more than typical "finned" impeller designs (stock and flow kooler) that rely on the clearance between the fins and the timing cover to seal and build pressure. More pressure in the cooling system prevents steam pockets from forming and reduces cooling system temperature. One of the most important changes on our 455 pump is the sealing surface between the inlet cavity on the pump and the impeller which doesn't exist on any other pump (the surface between the impeller and the triangular inlet cavity in the picture below, up and left of the part number). Our pump casting seals against the timing cover so that the inlet and outlet cavities are separated from each other. A stock type pump (and flow kooler) is "open", so pressure on the outlet side can bleed back into the inlet (high to low-pressure differential). Very inefficient design that we corrected."
I run the same combo but with the clutch fan ,..never ever gets over 180 idc if it's 110° ambient Only difference is I run 160 in all my Buicks Reason being from my experience with these cars is the 190 doesn't start cooling it down fast enough so it just "runs with a headstart" if you feel from the engine not having water going thru it till it hits 200° and it just can't recover,...try a 160 stat
That's the non ac pullies,...they worl great on my pops car but the AC pullies will spi. It faster at all rpms The fans need to turn on sooner also,...put it on a switch and hit them at 180°
Jup, you found it: " The p/n's for these pulleys are stamped on them and are as follows: water pump - 1375141 dia. 6 3/4 " one groove balancer - 1375142 dia. 6 1/4 " two groove The water pump used with these pulleys is the 6 blade pump." As you can see on the picture, I have the 5 blade pump. Which makes sense if my 430 came off an A/C car: " The p/n's for them are also stamped on them and are as follows: water pump - 1375146 dia. 5 5/8" two groove balancer - 1375143 dia. 7 3/8" three groove, with one groove 5 3/4" This setup is used with the 5 blade water pump .." Looking at my old fan, that would have been the case: I guess the fan clutch got lost, I've never had that. So, I have the correct pulleys and wrong pump. The Taurus fans are widely used on big blocks and should pull plenty of air. The radiator there is also cold, so it cools. I can also see it flowing. I have the wrong combo, that's not gonna cut it. Those TA pumps look interesting. I could also opt for different size pulleys, but I'm not sure how that would affect my alternator.
I would go with the TA pump or the Flowkooler. I have used a flowkooler and it was good. As stated above, the TA pump has improvements made over the stock casting. The flokooler is just a stock casting.
I am going to repost a answer I gave someone else in a different post on the same subject. I went through this in the past and I am confident a water pump will correct your issues. You just can't use a 5 vane pump with the small non A/C crank pulley without a compromise of flow at idle. I used a Flowkooler pump but I would probably buy a TA pump if I did it again. The problem at the time was that the TA pump cost by the time I had it shipped to Canada in my dollars was just too much. That said the Flowkooler pump has been performing excellent and my car has run nice and cool even in the hottest weather now. It sounds like you are on the right track. Get rid of that pump. I am pretty sure your electric fans are adequate. I would drop to a 180 thermostat though. I personally think 160 is too low. Here is my previous post. "I have had a similar issue. No problem cooling when moving but temps would climb at idle. I had been chasing cooling issues at idle on my 66' with transplanted 455 for years. Last year I installed a new Aluminum rad with 2 row 1.25" tubes. While it did run cooler I still have had issues with cooling at idle especially in traffic. I noticed that I had almost no coolant flow at idle. After some research I found out that BB Buicks can have this issue when mixing parts from different applications. A/C Buicks used a large crank pulley with a small Water pump pulley to overdrive the water pump by 31%. The A/C cars used a 5 vane pump because it turned faster than the Non A/C cars. This was also to increase the fan speed for the clutch fan that was used. On an A/C car they had a 7 3/8" Crank Pulley driving a 5 5/8" Water Pump. 800 RPM idle would equal 1049 RPM for the Water Pump. On the non A/C car they used a 6 vane pump that was under driven. They had a 6 1/4" Crank Pulley driving a 6 3/4" Water Pump Pulley with a fixed blade steel fan. This would be 7% under driven for the Water Pump and Fan. 800 RPM idle would only equal 741 RPM for the Water Pump. Finding A/C pulleys or using a high flow pump from TA or Flowcooler were looking like my only options for more coolant flow at idle. I ended up purchasing a Flowkooler pump. It is a very nice high quality piece. Turns out I had a 5 vane pump installed which would have made the cooling issue even worse. With the pulleys I have it should have had a 6 vane. I just installed a FlowKooler pump and it made a huge difference. You can see significant flow at idle now. Temps are in control and much cooler now. I have posted a picture of the two OEM pumps. You can also find lots of info in the link below about the pulleys and pumps. If you are having issues with temp at idle on your BB Buick consider this info. http://www.buickperformanceclub.com/455pulleybrkts.ht I have a fixed pitch 18" fan out of a big Cadillac sedan deville along with a pusher electric fan on a thermostat. Temps are holding right on 180 now pretty much no matter what. That is running a 180 thermostat. Sounds like you have a plan to check a few things but I think you should consider water pump and water flow. Good luck with it.
Anyone experience with the stock replacement pumps of TA? My engine is stock, nothing fancy. So if those would compare to the old 6 blade pumps I should be fine. $60 vs $230 without shipping and customs in Europe would be a steep difference in the end. And the Flowkooler would end up in between, but I kinda lean towards TA.
As far as I know, all stock replacement pump’s available of the last 25 or 30 years are 5 vane only. Only option that route is to find a NOS one on EBay or a used one. I have one good used one in all my parts but I am using it on a 430 I am building for my Wife’s car. It is a budget build. I feel you pain. I am in Canada and getting a TA Or FlowKooler pump up here is significant in cost. I am sure it is worse to Europe. Greg
Once you address your water pump, think about running more initial timing as this also helps the engine run cooler at idle. If you do this, you may have to limit the amount of mechanical advance the distributor is creating to compensate for more initial timing………but your 455 will like it.
I have flow kooler, I bought it prior to knowing about the TA pump. It seems to work well, engine stays very cool.
Much as I distrust electric fans; I have to ask: What sort of shroud are you using on that "Taurus" fan? How much of the radiator does it cover? Does it have "vents" or "outlets" that open when the vehicle is in motion, but close when stopped? Photos of the fan/shroud? The rule-of-thumb, which is NOT always correct, is that overheating at idle is generally too-little airflow, overheating at speed is too little coolant flow.
The one that's attached to it https://www.rockauto.com/en/moreinfo.php?pk=274870&cc=1138766&pt=2181&jsn=10 I'd say 75% of the radiator is covered: Don't know if it has flaps, actually. But the radiator is almost cold when the fan is on. There is just to little coolant flow at idle, so the heat can't dissipate. I'll give TA a call today, see what they recommend regarding the pump.
I manage to cool my 470 with a 21 year old Griffin Radiator, a stock 18" x 7 blade clutch fan, and stock shroud. Can't imagine why you would leave any part of a radiator uncovered like that, not to mention the added complexity of an electric fan.
Here's what it took to get my 462 under control in all conditions: 160 hi flow Robertshaw thermostat, 7 blade 19" fan on a non HD 4 seasons clutch, Flowcooler waterpump, HD/Stage 1/AC coolant pulleys, Cold case 2 core aluminum radiator, 70 Cutlass radiator side baffles.. Now of course it has no heat at all and I dont even think the thermostat opens all the way in this weather, but in 95 degree heat I can race and cruise at 3200 rpm. Thats what it took for me.