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Running hot...or not?


iowa51

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Manual or not, would keep an eye out for any issues........

Having said this, do not think oil pressure is the issue with his engine temps...

Maybe there is no issue, just the temp this engine wants to run at, and if it's not boiling over and running well, maybe not a big deal, for me, I could see this happening in a Tim Hortons drive through, but a parade, not for this cowboy...

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My truck manuals say 20# at idle and 40# to 55# at 1800 rpm or 30 mph depending on which one you look at.

My engine is a '54 230 from a 1.5 ton dump truck and has always idled at right around 40# oil pressure.

Perhaps this varied over time? and later engines ran with more pressure? Not sure but I know I would always prefer to see that gauge reading around mid range rather than nothing.

 

Jeff

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Is it really near 0? 

I think there is some paranoia here. My 65 year old never rebuild 230 when hot and idling at 450 RPM will idle at 10 psi, and rapidly rise when I blip it, rising to 25 at 650 RPM and practically live at 45 any time I am above idle, as a matter of fact the blow off valve must open at 45 because it never rises above that, even cold. 

 

I know this is a different engine but my '65 VW idles at 5 psi hot and the oil light does not come on above 2.5 psi.

 

 

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Time will surely tell.

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It sounds like some base line info is needed on the car, before this spirals. First, what is the timing? Has the carb been tuned at all? Has the engine been tuned at all? Unless I am reading wrong, it sounds like the engine was put in and nothing else. For all we know, the timing may be retarded, the engine may be running lean, could be an ignition issue, or a mix of any of these. Methodically rule out the smaller issues before going into bigger.

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  • 1 month later...

It sounds like some base line info is needed on the car, before this spirals. First, what is the timing? Has the carb been tuned at all? Has the engine been tuned at all? Unless I am reading wrong, it sounds like the engine was put in and nothing else. For all we know, the timing may be retarded, the engine may be running lean, could be an ignition issue, or a mix of any of these. Methodically rule out the smaller issues before going into bigger.

 

 

Working on the car on and off the past month or so.

 

New spark plugs/wires.

 

Replaced the water pump. The one on the engine was kind of crusty looking so replaced it to rule that out.

 

Took the radiator out and had it pressure tested (15 lbs?) and the shop owner did a flush test and said everything appeared to be OK without taking it completely apart.

 

Reset the timing to 0 deg TDC. It was a few degrees off. Starts better now.

 

Between removing the radiator, water pump, and opening the pet cock on the block drained most of the antifreeze/coolant out and replaced with new. Filled it up to an inch or so of the top of the radiator.

 

Ran the car at idle for 40 or so minutes in the garage with the hood closed (garage doors open) and the dash gauge was at the 7/8 mark when I shut it off. A digital thermometer held against the brass fitting where the sensor goes showed 175 deg.

 

Bought a analog temperature gauge at Advanced Auto and again ran the car for 40 minutes in the garage and it was reading 200 deg. Digital thermometer on the fitting again read 175 deg. 

 

Both times nothing came out of the radiator overflow tube.

 

Is this an OK temp? If so, why is my dash temperature gauge reading so hot? Is there an adjustment? Like I said before with the old engine the gauge (same gauge) rarely went past the 3/4 in any type of driving conditions.

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Have you checked to see what temp the stat actually opens at by putting it in a pot of water on the stove?   If you have an extra old stat you can "gut" it by taking the valve out so it acts as a restriction plate and try that in place of the stat.  If you do that you know the system is open and circulating and the plate will provide enough restriction for the rad to be able to draw off heat.   I've had thermostats that didn't open at the correct temp before. 

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Have you checked the manifold heat riser valve to make sure it isn't stuck in the closed position?  That would cause the engine to run hotter.  

 

I once read that if the cylinders are bored too much it increases their surface area with the result that more heat is transferred to the cooling system, raising its temperature, 

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Have you verified the readings of your gauges by immersing the senders in known temp water and comparing them to an accurate thermometer? What mix of coolant/water are you using? What is the boiling point of your mixture?

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Have you verified the readings of your gauges by immersing the senders in known temp water and comparing them to an accurate thermometer? What mix of coolant/water are you using? What is the boiling point of your mixture?

I now have 3 thermometers in my garage, the analog temp gauge I just bought a few weeks ago, a digital wall thermometer and a digital probe type that looks like a cooking/meat thermometer. The wall thermometer and the probe type read the same at room temp. The analog and the probe type read the same when stuck in the radiator fill hole while the car is running. Other than getting a certified thermometer from work (which they wouldn't allow) I would think my thermometers are reading relatively accurate. 50/50 mix. Figured boiling point is about 225 deg with 4 lb cap.

 

 

Have you checked the manifold heat riser valve to make sure it isn't stuck in the closed position?  That would cause the engine to run hotter.  

 

Would it be stuck open or closed to cause it to run hot?

 

I know it isn't stuck (rusted) as I have moved it back and forth and wrapped the spring 350 deg around like the service manual said and in the same direction. Seems pretty tight. However tonight I marked the shaft with a marker and it never moved even when the car got up to operating temp so it could be staying open/closed. Brand new spring when the manifold was off. Another problem!! 

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Is this an OK temp? If so, why is my dash temperature gauge reading so hot? Is there an adjustment? Like I said before with the old engine the gauge (same gauge) rarely went past the 3/4 in any type of driving conditions.

 

No. The temps you report are not ok for that engine. Those temps are too high.

 

1. Taking the temp from the outside of a brass fitting is misleading at best, and useless.

2. The proper temperature is taken where the original gauge's bulb is; at the back of the block/head inserted into the coolant.

3. In a healthy engine, the normal coolant temperature at the gauge's bulb should be between 160 and 180 degrees F. This would be with the stock cooling system.

 

If your temps are actually as reported, your engine was likely poorly rebuilt. The most often seen culprit would be the water distribution tube not being replaced, or was replaced badly. This would create poor circulation of the coolant over the length of the engine and higher than normal temperatures. The most immediate problem with overheating like this on these engines is burnt valves at the rear of the block and blown head gaskets.

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