Hello all, Need some help trying to diagnose overheating problems with my Wildcat. Standard 401 nailhead with a Dynaflow. Pertinent info: Car has been stored for a LONG time, but runs fine and has no apparent problems Original radiator, no A/C, the small 4 blade fan and no fan shroud The problem I'm having is that the coolant keeps boiling. Seemingly at far too low a temperature, when I first got the car is was boiling well before the HOT light on the dash even came on. I have also noticed (potentially unrelated) a lot of moisture in the exhaust even after the car has been running. So far, I've done the following: Week long system soak with cooling system cleaner, just flushed that out today Brand new 5 blade impeller water pump installed (original three blade pump had a wobbly bearing, and the impeller was eroded) New 180* standard type thermostat (the original appears to have dissolved ... the steel housing was there but the brass parts all gone) New 16lbs radiator cap New radiator hoses (I retained the spring in the lower hose) When I replaced the water pump, I found the passage from the pump into the passenger's side of the block had a pretty good blockage in it. I was able to clear that out mechanically using several long tools, and then flush water through that side of the block. The water neck looked clear, as did the other block passages. The car currently has a 30/70 mix of antifreeze and distilled water. All the work done, I'm starting to get coolant boiling right about the time the HOT light comes on. I can let the car idle for perhaps 15 minutes before it gets too hot, or I can drive about 2 miles at around 45 before the light comes on. I do not have a temperature gauge installed but will be getting one soon. Should I be looking for more blocked cooling passages? The radiator is definitely flowing coolant and does not appear to be obstructed. I did a fresh oil change on the motor last week, and the oil which came out showed no signs of coolant. I have also seen no signs of contamination in the cooling system. My assumption had been that the worn water pump and old coolant were causing my problem, but that clearly is not the case. Thanks in advance for any suggestions!
Where is your timing set? Retarded timing can contribute significantly to overheating. Have you made sure the system is free of air since you refilled? One way to help make sure it is free of air, is to drill a 1/8" hole in the side of the thermostat so that it doesn't create an air lock. Also, try to run the heater for a few minutes to see what that does. I would install a mechanical temp gauge on the car to get an accurate temp reading. Have you made sure the radiator is not clogged? When the engine is hot, feel the core of the radiator. If it is evenly warm, then it's clear. If you feel cold spots, you need to have it rodded out or recored.
It sounds as if this engine was severely neglected when it comes to cooling system maintenance. If so, there is NO WAY that your radiator is any good. Once they are clogged, there is no way to clean them out as good as new. Either get a new one or have yours re cored.
How did the timing cover look beneath the water pump? Since they are aluminum, pitting can cause cavitation. Since your old impeller was eroded, I suspect the timing cover is also no good. Cavitation can cause overheating as the coolant does not flow as smoothly, which goes along with Larry's suggestion about past poor cooling system maintenance. Been there and done that.
Hopefully I don't miss anything: Timing set by the book. 10* advance no vacuum, 12* with vacuum at idle, total advance about 32* degrees (IIRC) at 2500RPM ... it matched the specs in the service manual. I did not think to purge the system of air, I've had that problem in some other engines so I will try drilling the thermostat. I did run the heater and after flushing the core I am getting pretty good heat inside the car. I have a gauge here I am installing in a bit. I was skeptical of the radiator at first, but the passages certainly look clear, and it does get uniformly hot when the coolant is flowing through it, and there is a significant gradient across it from top to bottom. Not ruling it out at this point, as you suggest, but since it does seem to be working I wanted to triple check all my bases. Are the radiators in these cars that undersized? The timing cover looked fine, to me. The seat was smooth beneath the impeller, though it did appear to have a slight cup to it (not sure if they were designed like that, or the impeller with the bad bearing may have been hitting it?). There was some scale built up around the passages, which I cleaned out. Is there any good way to check out the internal passages in the block without completely stripping it? Pulling freeze plugs or other such? Please forgive my ignorance on this subject, I've been a small block Chevy guy for years and this is my first nailhead. :grin: ---------- Post added at 01:28 PM ---------- Previous post was at 11:44 AM ---------- Updates: Drilled thermostat, filled block to the water neck while it was out, then finished fill from the radiator. Installed a temperature gauge at the plug on the rear of the driver's side head. Drove the car maybe 1 mile, then idled it for 10 - 15 minutes. Temperature got up to 190 driving, and then crept up to about 215 while idling. I unfortunately had to cut the test short as I have an obligation this afternoon - I am not sure if it was stable at 215 or if it was still creeping. Did not boil, though. I think it may have been vapor lock in the pump.
Further update. Photos of old pump. I believe the car must have sat with only a partial fill of coolant in it.
Sounds like you might have fixed it. With the unshrouded 4 blade fan, I don't think 215* is unreasonable for an extended idle time. That setup doesn't move much air. And for future reference, I believe the HOT light comes on at about 248*.
CameoInvicta, I wish! Took the car out for a drive this morning, after about 4 miles it was running 190 or so, and then steadily crept up. The hot light came on right about 250*, I got a total of 6.5 miles driven before I had to stop and let the car cool off. That said, significant improvement over the way it was behaving before. I also noted the coolant which was boiling out has a LOT of deposits dissolved in it, so the cleaner is definitely working on the block, at any rate. Anyone have a good suggestion for a new radiator source? I'd prefer to keep the stock copper/brass type if possible. Not adverse to a larger core, though!
It really sounds to me like there is a lot of gunk in the water passages. I would repeat the cleaner several times until it runs clear after a treatment. There may be a shop which specializes in this, you might ask around. Be sure there is no air getting into the system. Mine had that problem and it ran very, very hot. My radiator was shot so I replaced it with an aluminum one. Wasn't an exact match, but it works. I'm not really sure if you can even get a brass/copper radiator these days, but one thing is for sure, it would be expensive as it would have to be custom built.
Like I said, if your cooling system was that neglected, there is no way on G-d's green earth that your original radiator is not at least partially blocked:grin:
I have been suitably chastised on that point, haha! Well played, sir. I know you can still get the copper/brass radiators, as I bought one for my truck not that long ago. It was a tad pricey but it works like a champ. And yes, definitely planning to run some more system cleaner through it. Right now I need to get it so I can drive 10 miles without overheating, then I can go get an inspection sticker and be legal for the year :TU:
I'm not sure of a source for a new copper/brass radiator. All the new ones are aluminum. Champion makes a drop in aluminum replacement. The other option would be to have it recored. I had mine recored, but it didn't last too long. I ended up with a universal aluminum unit from Jegs. I think you are on the right track though. Do whatever you can to get the cooling passages clear, then replace the radiator.
While I'm thinking on it, slightly different question: Is it normal for the car to have faint white smoke / vapor and moisture from the exhaust, even when warm? It does not smell like burning coolant to me. Just like water. I haven't noticed any cross contamination between oil and coolant. I'm planning to run a compression test this weekend, hopefully put my concern about the headgaskets to rest.
Water can condense in the muffler and pipes. It can take quite a while to burn off. Doesn't sound like you have been able to drive the car long enough due to your overheating problem.
I agree with Larry, especially around this time of year where the temps and humidity can change drastically.
If you recore the old rad be sure to do it with a 3 row. I had mine done and stuck with the original 2 row. Now I am kicking myself in the arse. Here is a link to the Champion on Ebay. Looks like a fit but can't say for sure. It would have to be exact to make the stock hose's fit. I believe this one is a non air model. The top hose configuration is different for the one with air. Keep us updated, I'm interested to see what comes of this.
Interesting. My radiator (which as far as I can tell is original, it's the correct vintage Harrison and I was told it was original) has 3 rows to it - I was actually looking at this: http://www.usradiator.com/buick-wildcat-1961-64-v8-radiator.html And I figured I would get their 4 row model with the "high efficiency" core. I have not done this yet, as I am still not sure if I am going to pull the trigger on a manual swap this winter and want to get the correct radiator/trans cooler combo. To this end, however, I have been making progress. I've gone through about 4 different chemical flushes at this point, and I have definitely made progress. The last time around, I basically ran the car up to temp and then just let it pump all the hot water straight out of the car and kept refilling the radiator. Got a LOT of scale and crystallized old coolant out of it. I can now drive the car locally, after it reaches op temp (around 185), it slowly creeps up to 230 over the next 10 miles or so, and doesn't seem to go above that. There is still a definitive cold spot in the center of the radiator core. I'm going to have the radiator rodded out this weekend and hopefully that will tide me over until I get a new radiator for the spring.
If your radiator can handle being rodded out, then it should not need replacement. I did the same thing to my radiator this Spring...holding up fine for a 55 year old core.
Now that you brought up this subject it has got me thinking about my car that runs about 220. So, just searching the web I found this page and it gives some good basic info. Seems that there may not be a quick and easy fix to the problem. http://www.rootesparts.com/id201.htm Yesterday I advanced the timing to about 14 degree (I think) no markings after 12. Seems maybe a little cooler but it was only 75 degree outside and not the usual 98-102 like in August when I drive it the most. Bty, I use the original shroud, put on a better fan blade and moved it much closer the rad. The rad was recored a few years ago and the pump was replaced many years ago, I cant remember how long ago or if it was the 3 or five fin pump. Wish I could tell without removing it.ou:
