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Topic Review (Newest First)
09-12-2012 05:12 PM
RWENUTS sbnova. If you look in the top left corner of all posts you'll see a date on it.
This thread is 3 years old. Likely the problem was solved a long time ago.
09-12-2012 04:13 PM
sbnova If you have a flex fan try a solid 5 blade fan. It solved my problem in my sbc. I could idle all day at 180 as soon as i got on the road the temp shot to 210 and up. Changed the fan and the engine wont go over 180.
09-01-2009 12:11 PM
kirkschopped67 sbchevfreak's


Thank you for the post. I did not know how it works. I now understand why we need t-stats now. I am going in for a tune-up at a local hot rod shop. I will post the out come and how well the truck performs.

I am having second thoughts on the torque converter that was chosen for me. I will post about that later today, because I do not believe this application is correct for the driving I want to do.

Kirk
08-31-2009 06:57 PM
sbchevfreak
Quote:
Originally Posted by sunsetdart
Running without a t-stat with a water based coolant is a no-no, ...reason why is that a water based coolant needs to develop pressure for it to work properly. Without the t-stat the system does not get up to the correct pressure.

Not exactly. Even without the t-stat, pressure will develop. The reason for pressure ais basically to crank up the boiling point of the coolant's water base. For every 1 psi pressure increase, the boiling point goes up 3.25 *F. What running without a t-stat does is allows too much flow through both the rad and the engine. This prevents heat saturation of the coolant. The coolant does not stay in contact with the heat bearing areas of the engine long enough to absorb enough heat energy, and then does not stay in the rad long enough to transfer any heat energy to the airflow through the core. This causes a compounded effect of some heat removed from the engine, but not enough released to atmosphere. You then end up with overheat, as well as localized hot spots in the engine.
08-31-2009 11:57 AM
Bryan59EC Less tha 13volts at the battery really screws up the gage readings as well.

low voltage/bad connection will show a high temp (in my case 30*)
It will also cause a low oil pressure reading (as much as 20#)

I spent 2 years beating on an overheat condition that was really just a bad alternator.

My 454 in the 59 ---base timing at 18*
08-31-2009 10:28 AM
kirkschopped67 I had pulled out the t-stat that morning, but I did not run it. Someone knew what I was thinking. So that night I went and reinstalled the t-stat. I figured that the t-stat was not the problem and It would not fix it . The timing and the jets in to be adjusted to work together.

Kirk
08-31-2009 10:08 AM
sunsetdart Running without a t-stat with a water based coolant is a no-no, ...reason why is that a water based coolant needs to develop pressure for it to work properly. Without the t-stat the system does not get up to the correct pressure.
08-31-2009 09:20 AM
kirkschopped67 Yes here are the updates. The first thing is the timing was retarded. I advanced the timing and the temp started to fall with in a minute or so. On the highway it was over 230 degrees. It dropped down to 212 degrees. Still not happy with the results; I did a spark plug test. I ran the truck at 35 mph for a 1/2 mile and shut the engine off and coasted to a stop. Right there I pulled a plug from each side and found that it was still running to lean. I made an appointment to take it in to a Hot Rod shop where I live to have the jets changed. Out of the box there is no way that all these parts are going the be able to work together without being adjusted.

I did go to a car show this weekend. I had to set in line for about an hour. The temp stayed at 183 degrees and it was 102 outside. Advancing the timing really helped. I will have it tuned and I believe it will solve a lot of problems

Thanks for the help, I needed it.

Kirk
08-29-2009 11:49 AM
dawg any updates?
08-28-2009 03:39 PM
dawg
Quote:
Originally Posted by kirkschopped67
You said; running without a t-stat in a BIG NO NO. I believe what you are saying; but what effect does it have in the end. I know now it can not be good. I am just trying to learn.


Kirk
the T stat does two functions
1. it gets engine up to operating temp faster
2.it also acts as a restrictor of sorts.
if coolant flows too fast it wont absorb the heat effectivly.
you can also have a faulty thermostat.
I cant remember how many I took back for not opening all the way.
I would test it in boling water to see if it opens fully.
but i suspect that your fans dont have a good shroud.
but alas ol DAWG knows where to get good one fairly cheap.
check them out here.
http://www.coolcraft.com/shrouds.html
08-28-2009 02:43 PM
kirkschopped67 That is a possibility. I will check it tonight. I have made notes of all the suggestions and I will keep everyone informed of the end result. This is how we learn.

Kirk
08-28-2009 02:32 PM
302 Z28 Running hot at highway speed is indicative of a radiator problem ( discounting an engine problem) . Either it's too small or air flow through it is insufficient. Perhaps your electic fans are restricting air flow too much.

Vince
08-28-2009 02:13 PM
kirkschopped67 The truck is a 67 ford pickup. The radiator should cool up to 700 hp. It is from BeCool. The front of those trucks can except a lot of air flow. In town at slower speeds I run the fans, and it runs around 200. As soon as I run it at 50-60 mph the temp starts to climb. I manually keep the fans on and I have shut them off, and there is no change. I am beginning to think this is a timing problem. I will set the timing tonight and check the plugs for how lean it is running.

Running without the t-stat??

Kirk
08-28-2009 01:43 PM
oldbogie
Quote:
Originally Posted by kirkschopped67
I know this topic has been beat to death. I have research this site and read a lot about the subject.

I have a big block 460 ford crate motor that has just been broke in. I have Dakota Digital gauges and in town under 30 mph w/electric fans running the temp moves between 195 and 210. As soon as I take it out on the highway, (55mph) the temps quickly begins to rise to 225. Last night going up the hill to a car show ( 1000 ft elevation) the temp quickly hit 231. Once I came back down the hill the temp still wanted to stay at 218. I was hard to keep running at a stop light. Can you give me a list from first to last of things to check and what might be the problem.

Electric fuel pump
750 holley carb
gear drive
cobra jet heads
Aluminum Radiator from BeCool
MSD electronic Ignition
Cool Flex hoses



I need help so I do not ruin this motor.

Thanks
Kirk
Typical of not enough radiator, to a lesser extent lean mixture, retarded timing of either or both cam and distributor.

What is this engine installed to? Many custom installations in classic 1920s thru early 1940s bodies have trouble flowing enough air thru the core at speed. Especially prevalent with open hood installations where the air flow finds it easier to go around the radiator core than thru it, this problem only gets worse as speed goes up and mysteriously goes away at idle when the fans are effective.

My first guess would be the aluminum radiator is either insufficient in size or has an inability to keep air passing thru it as speeds go up.

Bogie
08-28-2009 01:41 PM
kirkschopped67 Yes it is.
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