Running HOT AGAIN

[Lemon Owner 11]

My waterpump pulley is a butterfly's breath away from the crank pulley so I would say it's normal.

[Max Power 74]

I still want to know why pulley and water pump etc are supposedly bad yet it consistently runs 170 degrees at speed. If any/all those things were bad, why doesn't it overheat at speed? The engine creates more heat at speed, the only difference is airflow. What should that tell you?

 

I am not sure this car is behaving that much differently that it did when it was new.

[rc4mike 10]

My waterpump pulley is a butterfly's breath away from the crank pulley so I would say it's normal.

 

My pulley is similarly close to crank but I have overheating issues at high speed w a new alum large rad. I have A/C and it really overheats fast w ac on

[MikeStang 247]

I think the pump is probably OK at this point, i did see water moving with the water level a bit lower at idle, so its safe to say we can rule out the thermostat AND the Water pump...after all i have had 4 different thermostats in it, & have seen the pump moving water at idle, but whose to say its enough?

I would however like to know the stock diameter of that water pump pulley, because the one i have now is in excess of 6", so that may be what is causing the problem, and i know an AC equipped car had a smaller pulley, just not sure how much and if that would make a difference.

Also the new 4 core fan shroud fits very well, BUT with the way its made, its spaced OFF of the radiator almost a half inch at the top and bottom.....whould there be a rubber or foam seal in there perhaps....My fan is just a bit Over half way in the shroud, i may try to move it Back away from the radiator a bit, and fill the gap in the shroud next, in every attempt to help out, short of putting one of those spray bars across the front that the turbo guys use to spray their intercoolers LOL.....I now believe this problem to be one of an Air flow nature, altho the pump and thermostat may have been contributing to it.....

Gonna make changes tonight, then report findings, and ill let yall know, also i will post pics of the shroud distance and fan distances.

Mike

[LoneWolf2U 136]

Pulleys are sized from 7.1/4 to 5 7/8 for Ac engines.

The smaller the pulley the faster the pump will turn.

Higher rpm of the pump, the more coolant will flow.

 

Fan should be half in and half out to be at best flow rate.

Too far in and it doesn't dispatch the hot air as good.

 

Also sealing the shroud is an excellent way to draw more air thru the rad and not around it.

[buening 63]

I use this website to verify pulley part numbers that are on my car. http://www.mustangtek.com/pulley/Pulley.html

[1969 Mach1 14]

MikeSang:

 

I think in my first reply in this post I mentioned insuficient air flow through the radiator is the typical cause of cooling problems at idle and low speeds. The non-A/C pulley set up on my 351W is identical to what you are describing. Mine use to do the same as yours with a 4-row copper brass radiator. I think there is something with the design of the 4-row copper/brass radiators that makes them not as efficient as they look to be. With the aluminum radiator I installed the temps still climb higher at idle then at cruising but at least they seem to only climb to about 185 deg. or so with a 160 deg. high flow stat. For your situation it is probably worth trying the smaller A/C water pump pulley like you are planning. Also, like Mach1Rider mentioned, sealing the gap between the shroud and radiator is a good way draw more air in through the radiator.

 

What type and size of 6-blade fan are you using? Some of the flex or fiberglass fans just don't move much air even at low speeds.

Edited September 21, 2011 by 1969 Mach1

[MikeStang 247]

I misquoted ...The fan is a 5 Blade stock style fan, didnt know the stock 5 blade fans would actually work kinda like a flex fan when revved up lol...have to measure the diameter, but it fills the shroud out.

Tonight, I sealed the radiator to shroud with some nice rubber weatherstripping at top and bottom, the sides are butt up to the radiator, I installed a shorter spacer to move the fan back to exactly half way in and half way out, then took it on a ride....It runs 160-165 when moving, when stopped it climbed to 190 when i got home and sat it still with it in gear, I shut it off and came in the house as disgruntal as ever.

The fan moves air pretty good, but i just dont think its enough, kinda disheartning.

Im not sure where they actually take the measurements for the pulleys at, i measured mine while i had it off and the outer dimentions are over 6", probably around 6-1/4 maybe a bit more, but when you measure the bottom of the groove the belt rides in its 5-7/8 which i am being told buy mustang parts places is the right size for AC cars....John's mustang did say 5-13/16 was for ac cars, but thats only 1/8" difference WTF....I cant even get the water pump pulley on with the AC Crank pulley, so its gotta be too big...when you try to slip it on it hits the larger front ac belt groove and dont have enough room to go on, no matter how much you tilt and play with it :( maybe i just hunt for a smaller pulley off of something else, but then im worried about overspeeding the AC compressor.

Lost now guys....

[buening 63]

Look for the part number on the face of the water pump pulley. Then look up the number on that link I provided to see what motor and with/without A/C.

 

For example:

 

 

is casted onto this pulley:

 

 

 

and appears correct for 69 mustangs with A/C. It measures 5.86", which confirms what Johns Mustang said of 5 13/16"

[MikeStang 247]

Ok buening, but heres the thing, isnt the 5-13/16 only 1/8" smaller than a non ac pulley?

And where is the measurement take from, in the groove at the bottom OR from outside of the pulley.

My pulley is 6 plus inches on the outside, but down in the groove its 5-7/8

Which is 1/8" larger than the 5-13/16, so in conclusion there is appx 1/8 in difference if they are measured from in the groove, which will make no difference i dont think.

Mike

[1969 Mach1 14]

The outside diameter on my non-A/C pulley is 6-7/16" and my A/C pulley is 5.86" outside diameter and is identical with same casting number as what buening has pictured above. Use the link beuning provided and verify your cank and water pump pulleys. Another source you can try if you want to make a phone call is Perogie Enterprises. Their website isn't the best. But 1969 and 1970 Mustangs was their primary market and they almost always have the parts you are looking for.

[buening 63]

Regardless of the diameter you measure, just pull the part number from the pulley and look it up on that site. You could have one "close" but could be for a completely different motor. I'd also recommend getting the part number off your crank pulley and checking it against this website. That will eliminate two variables.

[MikeStang 247]

I will check my pulley casting numbers tonight, if they are off, i may have to take mine back from my buddy who i gave mine to for his AC LOL

Mike

[MikeStang 247]

What i dont understand, is WHY would it not stay cool with this pulley which i think is a NON AC pulley, which tons of other non ac cars used :/

Mike

[1969 Mach1 14]

MikeStang:

 

First of all, I think these cars had a tendency to run hot even when new back in 1969. The temps usually creep up as yours is doing, at idle and in stop and go traffic. Some time ago in high school my older brother also had a 1969 Mach 1 with a 351w, 90k original miles, complete and correct original untampered car, and it had heating problems at idle and stop and go traffic. The 289 and 302 Mustangs don't seem to have this problem. But the 351w and big block Mustangs do. I think this is in part due to the small engine compartment trapping in too much engine heat. Second, if your block's bore is 0.030" or more oversize heating problems can start to happen. Third, I also had a 4-row copper/brass radiator in my Mach 1 trying to cool a non-A/C 351w that is bored 0.030" oversize, and it couldn't do it. Mine did the same thing your is doing right now. The aluminum radiator helped drop temps on mine about 20 deg. F. I am NOT suggesting you go out and buy an aluminum radiator I am just saying the 4-row copper brass radiators don't work as good as you'd expect. It seems the copper/brass radiators ar not as efficient as aluminum and require more air flow than aluminum.

 

This thought just popped in: your radiator is not coated with a ton of paint, is it? I believe you are only suppose to use laquer type paint on them.

[LoneWolf2U 136]

What i dont understand, is WHY would it not stay cool with this pulley which i think is a NON AC pulley, which tons of other non ac cars used :/

Mike

 

First there are some unknown facts that may be the cause of the problem.

 

One is why there is not visual flow at idle in the rad.

This could be from clogged passages to an improper impellered water pump.

The pulley size will dictate speed in which the pump turns.

It may be that the pump you have on it requires a smaller dia pulley to run at the correct speed. But there in lays the unknown, it may have an incorrect impelleror coverplate placed in it when it was rebuilt?

 

Yes there are tons of other cars out there with and without ac that are working well cooling, but maybe they have a properly matched set of pullies and correct pump speed.

[MikeStang 247]

There is water flow at idle, i didnt see it Bfor because i had the coolant filled to top of water neck waiting on the thermostat to open and the coolant level to drop, but when i lowered the level i saw the fluid slowly moving.

Gonna check numbers on pulley...

numbers are C70E 8509-D

Guess its the wrong one,

Mike

[Lemon Owner 11]

MikeStang:

 

First of all, I think these cars had a tendency to run hot even when new back in 1969. The temps usually creep up as yours is doing, at idle and in stop and go traffic. Some time ago in high school my older brother also had a 1969 Mach 1 with a 351w, 90k original miles, complete and correct original untampered car, and it had heating problems at idle and stop and go traffic.

 

 

 

These cars do have a tendency to run hot in traffic. You have to remember back then there was no traffic! Every old car I have ever owned used to get hot when stuck in traffic and in the macdonalds drive through. It didn't get hot in five minutes flat, but 10 minutes in stop start traffic I'm starting to get concerned. And when you make them breath better it just makes it worse. And I know you have a 4 row aluminium radiator but your still using a crappy 40 year old engine and technology.

[buening 63]

Gonna check numbers on pulley...

numbers are C70E 8509-D

Guess its the wrong one,

Mike

 

Yup, wrong pulley. That pulley is roughly 1/2" larger diameter than the A/C pulley.

 

Have you also considered upgrading your stock fan to one with more blades and one with a clutch? I'm not too knowledgeable on the mechanical fan upgrades, but obviously the more blades the more air flow.

[Pakrat 1,043]

I upgraded my fan to a clutch fan and love and highly reccomend it but considering it's purpose is more to free up horses by not spinning until things get hot I'm not sure it will change your idle problem unless somehow the waterpump is able to turn faster and more freely without drag from the fan any longer. Since it's a good upgrade it probably woudn't hurt to try it especially if you need a new fan with more blades anyway, the clutch is pretty cheap and available at your average parts store.

[MikeStang 247]

PAk,

Not sure if i need more than 5 Blades...got a pump pulley coming so will tray that first then go from there.

Mike

[MikeStang 247]

Ok fan is a 5 blade factory unit....do i need to step up to a 6 Blade?

Installed the AC water pump and AC Crank Pulley....

The AC crank pulley i installed is larger than the one i had which was a non ac crank pulley, and the ac water pump pulley i installed is smaller than the one i replaced, SO this should make the water flow faster right?

Wellllll......It seems to be drawing more air at idle, and when cruising temps are fine 165-180 never higher than 180.....At idle with car in park, temps get to 180-185 and hold, throw it in gear and put on the Ebrake and in 10 Min she is 190 and climbing....Is this normal, because in stop and go traffice 10 min is pretty normal....You can throw it in park and hold the idle up and she will actually drop the temp but only to a point stays around 185 no lower when doing this...Its about 81-85 degrees and Dark here so its not super hot.....I guess the next thing is a High flow water pump :-/

I dont know if this is going to work tho, because this seems like an air flow problem, but i suppose if you could move the water through the radiator faster and get the water to cool a bit it might work?

This is such a PITA, may talk the guy to adding a small electric pusher fan for when temps climb, it will give the system a bit of help, especially once i get the condensor on and the AC working.

Mike

[LoneWolf2U 136]

I would change the fan to a 7 blade clutch system before adding an electric fan.

Edited September 28, 2011 by Mach1Rider
counted the blades

[MikeStang 247]

Thats what i was considering, but would there be any reason for a clutch versus a direct drive manual fan, aside from the loss of power, which aint going to hurt this car because it never goes over 50-55 mph LOL the owner will never know if he lost 100hp.....The fan on there now doesnt make much noise when your running the car either so that isnt a concern, really dont know if one more blade will make that much difference or not?

Thing next is going to be the high flow water pump, altho i dont think its going to help this air flow problem, i just dont know of any way to increase the airflow.....suppose i could idle it up more haha, problem would then be putting it in gear when idled up that high haha.

Mike

[LoneWolf2U 136]

Using the clutch fan set up will help.

Locking the fan when temps require more air flow and free wheeling when its not needed.

Not only will the two extra blades help flow, Check the pitch of them vers the 5 blade. IIRC they are turned more to draw more air.

 

On another thought, placing an electric fan in front of the cond may cause air flow restriction when the fan is not on.