I'm OK while driving, but running a little hot at an idle. It's a new build on a 350 SBC, so I expect it to run a little hotter than normal. I have heard of additives that help keep the Temp. down, "Water Wetter" being one of them. Anyone have any success with these products?
instead of a bandaid, you probably should address the problem, not trying to be a dick, just saying these arent your problem, Try fan shroud, size, radiator size and timing first, then fall back on gimmiks,
We need more info: What's it in, what was the overbore, does it have a hood fenders and inner fenders? We worked on a '40 Ford with a 350 in it; found out it was bored .120 over and would not work with inner fender wells even with a new radiator, shroud and 2 fans. Had to swap engines to fix it. Hope you don't have to go that far.
The water wetter does work, in my experience, but only by a few degrees for a street vehicle that runs 50/50 mix. SHaggy's right, solve the cooling problem. If it cools down when your going down the road, it's either retarded at idle or you have an airflow problem. Check your initial timing, not enough advance will make it run hot at low rpm. Make sure you have a good OEM style mechanical fan with a well fit shroud and all the cooling system components are in good operating condition.
I agree on the water wetter. I use it & it seems to work ok. What are you calling hot while at idle? Does it puke out the overflow?
It's in a '41 Ford Coupe, no bore on the 350, mild RV cam, Pusher Elec. fan, and sorry to say no shroud, I got lazy. I guess I gotta go build one. I was hoping to get by, but I guess it didn't work. I got pretty close though, the overheat is about 200 deg. I never put too much thought on the inner fenders, but sounds interesting. A double check on the timing would help.
A few of the things I have seen in the past with engines that run hot or seem to run hot. 1. Electric gauge that is way off from what it should actually read. 2. Radiator too small for the engine. 3. poor air circulation through radiator especially at low speeds. That is usually due to. plugged fins in radiator fan not pulling enough air or in wrong position in relation to radiator. Fan not designed to pull enough air. Those little skinny aftermarket fans are killers here. I almost fried the engine in my 48 with one of those. 4. Reverse rotation water pump designed for a serpentine belt being run with V belts. This is common when you go to the parts house and ask for a pump for the year model of the engine you are using an not telling them how you are using it. The opposite happens quite often also when guys swap to a serpentine belt system without changing pumps. 5. Bad or wrong thermostat. 6. Hose that is collapsing or bottom hose that is kinked due to the installation. 7. Engine timing that is late. 8. Wrong head gaskets for application. Not likely in this installation but it does happen. Like I said those are some of the things I have personally seen in the past.
This has been gone over many time,overheating at idle on sbc is common if the vacuum advance is not hooked to manifold vacuum.There are other reason but this is most common. My friend has a 40 4 door with a flex fan only and it doesn't overheat.
Yeah, thought I could get away without a mechanical fan by ducting the air and using a large tube radiator with the most powerful electric spiral fan made. Water wetter in straight water got it close, but still would climb to 210 in long stop and go traffic back ups. Had to give up the cool look and a few extra ponies using a shroud and clutch fan, but it will sit up against the shop door all day and idle at 185 now. Might not look as cool, but better than cooked.
could be the fan..pusher might not be the best choice..jmo a good mechanical fan if you have room is always a great bet, because when the beast is breathin fire the fan is pulling only 1 worry, belt. electrics you have relays wires switches temp probes fuses Jeasus cripes why would anyone want to do this when they have a 300HP fan motor is beyond me..again (unless they havent any possible room to run one) also..mechanical will always "look right" Nice Mr Woosh
One other possibility. How many miles on the rebuild? I had the 327 in my '67 Corvette completely gone through. Had the same problem; running hotter than it should when I let it idle. After I put a few hundred miles on it, the problem went away. My best guess is that the guy who build the engine had all the tolerances "stacked" to the low end and the engine was a little tight and had to break in. I was really worried, so I called the guy who did the rebuild and he said that if it was OK going down the road, it would "loosen up"; he was right. This probably wouldn't happen with a crate engine, but it makes sense for one freshly assembled and then dropped right into the car. You might have gotten lucky.
200* isn't really overheating. I've never seen a shroud on a pusher. What kind of water pump you runnin'?
I wouldn,t worry much about 200 deg. thats really not bad especially on a new build.I understand the feeling though. The fans in my C6 didn't come on till it hit 260 & never could get used to that!
Is there a chance that your fan is a traditional puller and you put it on the front. There are some fans that the buckets are cupped the wrong way to push affectivly and the fan as to be turned around
Pushers rarely work well. Pullers are more efficient. Few aftermarket electric fans are worth using, Spal is tops! Large OEM type pushers are the best, I like the Lincoln Mark VIII If you are running hot only at idle and not at low speed cruising then there is an airflow problem. Still running hot at idle and low speed cruising (15-35 MPH) most likely an air flow problem but could be a tuning issue like timing or an over rich condition. Stocker 350 like you describe should be fine even with a relatively small radiator like a Mustang/Falcon unit. I doubt it's a radiator efficiency issue because you did not mention the car gets hot at any other speeds other than idle.
I'm betting on the engine still being a little tight or the timing. Could also be water pump if it's a high flow unit. More often then not, a high flow water pump hurts more than it helps with the smaller radiators. Steven.
When will we all get over the 160* syndrome? 200 isn't overheating. I have a 190 thermostat in the falcon and it runs 190-210 all day every day, hot or cold. My 2005 Silverado likes 210, but could easily run 220 and never be at risk. It isn't 1958 any longer. Pressurized cooling systems allow us to run higher temps and get better combustion. Step away from the temperature gauge and relax. Overheating is defined by boiling over, over pressurering your cap, run-away temp, detonation, etc.
Got a SBC 350 in my suburban. Looks like previous owner just pulled a whole setup out of a mid-to-late 80s Silverado; radiator, electric fan, everything. Normal driving it holds 180f easy. Got stuck in a jam yesterday and the temp started climbing slowly. About 15 min later it is around 210-220F (which I don't consider that hot) it just dies and won't restart. Let it sit with the hood open to cool, I try to start it at 170F and everything is fine. Fired right up. Drives fine, runs fine, holds at 180F again as I drive home. When it was dead, plastic fuel filter was completely empty, and it felt like it ran out of gas. This is the first extended idling experience I've had with it. I recently put a 180F thermostat in it, and flushed the coolant as well.
Sea level here, but there's a marked difference to the way E10 and E0 fuel boils up once my engine compartment temperature gets above about 190 degrees. Possibly the same thing happening here, causing a potential leaner-than-ideal mix at idle?
Classic vapor lock [on todays fuels] Install an electric flow through type fuel pump to prime the fuel system If it dies while running , you need a return fuel line.
I figured vapor lock, but not experienced enough to be sure. Any considerations I should make before tackling this job? As most things with this truck, it's pushing me beyond my general "know-how"... I don't know anything about converting from a mechanical to an electric fuel pump. I also had dreams of replacing the original gas tank (it's seen better days) with a new one... worth combining this into one bigger task?
Good temperature at speed? Overheating only while sitting? Airflow. Pusher fan... bad. Puller fan... good. No shroud... less-than-ideal.
It's got a puller. No shroud. I'm not convinced a shroud would make a big enough difference... though I've been wrong plenty of times.
Thermostats do not cool an engine....They are strictly to get the engine up to a certain temp...160,,,180 or 190....If the cooling system temp is above the thermostat temp range it will stay wide open...
I second this comment…. Vacuum advance hooked to manifold should add about 16 degrees if idle timing advance which should help a lot. I also recommend using the B28 (echlin vc1810) which comes on full at 8” of vacuum to ensure max performance. Works great on 2 of my Chevy powered Rides
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