cooling problem

I'm still having trouble cooling my 455. I've seen in other postings about using a fan from a Lincoln MarkV111. Does anyone know what year(s) would have the 4000cfm fans? My 455 is a 1975 with 1970 heads, comp cam-469/268, comp lifters, Edelbrock intake & 750 cfm performer carb, new water pump, bored .030 over, new Howe aluminum racing radiator 28x19 with no trans cooler in it (external trans cooler), two electric puller fans. I've tried different radiator & changed the timing. If I can't get this overheating problem solved i may take the cam out and put in a stock one, change the heads back to the 1975 heads to see if that works. sorry to be long winded, but i'm running out of ideas. any help would be a god send. thanks, Duane

 

What thermostat are you using? Any at all? Radiator cap new? Makse sure your thermostat is opening. Check to see if the upper radiator hose is buckling when you give it gas.

What car is this in?

What temp is it running when it gets too hot?

 

i'm running a 160 degree thermostat thats been checked out, the hoses are fine. the temp is climing above 220 degrees and i added wetter water. it's in a 1964 riviera. thanks, duane

 

Is this a combo that you have been running for awhile and now its over heating? Or did you just do some work to the engine and notice the prob. right away? Is this a fresh rebuild and you have this prob?

Just trying to get an idea of where to start.:TU:

 

This motor is a fresh rebuild with everything new. It has ran hot since day one. It will run at 180 degrees for a while the it starts to climb to over 220 degrees. it's boiling over. I had been runing a 18# cap but changed over to a 22-24 cap as per Howe racing. Still running hotter than i like. It ran hot with a 4-core radiator and full shroud with different types of fans. I replaces the 425 that was in the car in hopes of being able to find parts easier and the 425 would overheat also. thank for the help, duane

 

Could it be the headgaskets?

Are you using headgaskets for 1970 or 1975?
Look for the water passage holes in the heads.

Maybe, it could be a difference between heads from 1970 and 1975.
I can be wrong, only a guess...

Someone else here maybe knows exactly if there are some differences between the heads.

If you locate the problem, i dont think you need the electrical fans either.

I hope you find out the problem.
____
Elis

 

Get the '97 up fan and make sure you wire it up on high speed. You'll need a high current relay and might need to upgrade the alternator.

For severe cooling needs, the electric fan from the Lincoln Mark VIII provides the greatest airflow. The part number is F8LH 8C607 AA and is available from Houston Performance for $149.00 plus shipping (as of 09/2002). This is a brand new Ford Motorcraft part and has a fan diameter of 18" and a uniquely shaped fan blade

http://www.houstonperformance.com/

The dimensions of this fan are 22"W x 18.5"H x 6.25"D.
This info was give to me by Matt W.
part # is F3LY8C607A

93-96 use p/n F3LY 8C607 A @ 245.80
The 93-96 spin 1100 rpmson low and 1850 on highspeed.

97's use p/n F7LZ 8C607 AB @ 196.23
98's use p/n F8LZ 8C607 AA @ 140.11
The 97-98 spin 1800 on low and 2225 on high.

They all look the same, all come with a shroud. The 93-96 spin slower according to Ford Motorsport Tech line.

 

Thanks for the info Scott, it's greatly appreciated. duane

 

wondering?

I was talking with a chevy man and he was wondering if the goose neck on the 455 was allowing too much flow like the 409's did and they had to restrict the flow or release some pressure to allow more cooling time in the radiator? Any thoughts? thanks, duaneo No:

 

Remeber that the cooling system is a closed system - the mass flow rate through the engine is that same as it is through the radiator. If you slow down flow, yes it will spend more time in the radiator cooling off, but it will also spend more time in the engine heating up.

 

The thermostat should be enough flow restriction to let the coolant cool in the radiator.

I ran my car w/o a t-stat for a little while until I realized I was making the coolant boil over every time I went on the highway. The cooland didn't have enough time to cool in the radiator. So I popped a 160 t-stat in and solved the problem.

 

Something else is wrong. You can take that set up on a hot day and run AC on our cars with no problem. Fan cover in place? Timing mark is really correct notwithstanding it appears to be in the right place? No Bars leak in your system? No coolant in the oil?

 

cooling

i'm running a new aluminum radiator (28x19) and cap, a 160 degree thermostat & two electric puller fans. The lincoln mark V111 electric fans are too deep for my set-up. I only have 4.5" from radiator to pully. I contacted comp cams again to make sure that the timing marks are correct. I going to have to play with the timing a bit along with the vacuum advance set-up. thanks for the help, duane

 

I think Elis is on to something. But I don't know jack about water passages between the different years of heads and blocks.

 

Just some more thoughts to toss out there, does it overheat in town but ok on the highway or the opposite??

Timing set with vac disconnected?

Maybe its too lean?? 750 is pretty small, these things like big carbs....I had an engine once that would start a slight miss at cruise rpm and would overheat there too, finally got it gas analysed and the thing was leaning itself right out in cruise...with a bigger cam in there and a smaller carb might be something to check. Quick tailpipe sniff is only like $50.00, might solve a lot of questions.

Also, some 455 waterpumps were different for a/c or not, some rebuilt waterpumps are crap too and don't flow anything....

I know you have probably covered all these but just some more things to check before you start tearing engine apart....on the head gaskets, using early heads on a later block is generally not a problem, if you use the wrong head gasket you will end up with water in the oil and that is pretty easy to check....pull drain plug and watch (water will come out first)....and it will look milky....i persoanlly have not heard of overheating problems by using worng gasket unless it blows or leaks....

later
Tim

 

Just some info here... I am running an Aluminum Rad with two puller fans To, Allways ran cool. Then My Holley 850DP took a dump so I had to put the 750 QJ back on... Imediatley I noticed at least a 20 deg. jump in opterating temps. Went from ideling at 190(HOLLEY) to 210(QJ) and average running temp was 175-180(holley) now will tip 200-215!!:eek2: Just from a carb that is to lean. But the engine runs great.. no stumbleing or hesitation, and also no pinging. Just a carb that is too small. I am also not running a Tstat.. (never needed one, but I might try one now).

Restrictions and Air pockets are a good thing to check for too. But if you don't find anything there, I'd try an 850 or better carb. Heck, your engine would probably like that better anyways:TU:

Good luck.

 

Carb May Be A Little Small.

Just a little food for thought. I too at one time ran a 750 cfm carb. My engine didn't operate as hot as yours, but it was always borderline hot. 200 - 210 deg. on a somewhat warm day. Yes that is with a four core radiator too. Nevertheless that was too hot for me and I struggled with this problem for about a year. I know what it's like to be stuck at one of those dreadfully long stop lights and watch the water temp. gauge steadily climb. ou: I knew my motor was under carburated for awhile, and it wasn't untill I stepped up to a larger carb. size ( which would be a 950 ) that my engine temp dropped about 15 - 20 degrees. This was completely unexpected, as I bought the carburator to go faster at the track. It made me aware that I was running my engine quite lean for awhile. On the hwy now, it is usually around 180 deg. On a cool winter day, it may not even climb over 170 deg. That's a little to cool for me. :eek2: In my humble opinion I think you have a lean condition and that is contributing to your high engine temps. As far as everything else goes, it seems like you covered all your bases. Good luck my friend.
John

 

Here's a little different cure we found for my 455 overheating problems. I have a high output electric Flexlite electric fan and the engine was really overheating once the outside temp got relatively hot for Vancouver, say 75. I wasted much of last summer trying to solve that and other problems and lo and behold the answer was trashing the 3 different Petronix's [or is that Petronii?] and installing Dave's rebuilt distributor with an MSD 6A system. That made a huge difference and after a few weeks I did a total flush, added some water wetter, and now it barely gets off the normal on my '49's old guage where before it was way up at high and boiled over after longer highway runs. Best of luck.

 

Mike Bucy,you are correct!

With that kind of stuff you mention, the engine should never overheat.

A no leaking cap is also important.
If the pressure is O.K., the differences between the cooling air temp and the cooling water temp, could be a lot bigger.
The boiling level for the cooling water is rised.

Because of that, a cooling system is a lot more efficient.
Air-cooled A/C-systems works on the same way.

Sometimes when buying new head gaskets, there are small plastic water restrictions to be used for different kind of heads.
Dont know if there is such a things for Buick.

____
Elis