Running HOT AGAIN

[sportsroof69 13]

It may cause starting problems if the timing is too far advanced, but if your heat issues are timing related, and you retard the timing, it will make it run even more hot. Advancing the timing will help it run cooler.

[MikeStang 247]

When i say Hard Starting, i dont mean that it wont turn over easily......It spins over just fine, you just have to pump the gas, and or hold it to the floor too make it fire off......When you first start the car you tap gas 2 times, it sets the choke, and you hit the key, and she fires off on the first spin of the motor....as long as the car doesnt get over 180 you can kill it and let it sit , then come back, and hit the key with out giving it gas and it fires right up....BUT if she goes to 190 and up, it will start to run rough, and once you kill it, if you let it sit long enough to walk into the store and get a coke, when you try to start it you have to either pump the gas, and or hold it to the floor.......The choke is set correctly and is open once she is warmed up, so i know its not flooding because the choke is closed partiall, hell if anything the hotter it gets the more the choke would open IF it were out of adjustment haha...when i rebuilt the carb, the previous owner had installed the choke spring backwards inside the housing, so when it got hot the choke would close LOL.......i know im not getting any nozzle drip because i have watched it, and it would take a good amount of nozzle drip to flood one, but having to hold it to the floor indicates to me that its flooding for some reason, im wondering the bowl is leaking down some how.

Heres something else......I am installing a water pump pulley for an ac car, which is smaller, BUT what did the old cars that were NON AC do for cooling with the larger pulley? They didnt run hot at idle ......makes you wonder dont it.

Mike

[LoneWolf2U 136]

From that discription you are having a fuel perk flooding condition happening.

Try lowering the float level down a 1/4in.

It is not coming out of the nozzle but thru the overflow ports, an indication of bowl leak/seek would be excessive cranking on first start up as there would be a lack of fuel in the bowl after sitting.

 

Buening has point on partually plugged passages, Or worn/improper pump as there is little to no flow at idle with your current set up.

I am basing my suggestions on a clean system as you have not stated there was any discolorations or chunks in the system.

Some non ac engines will temp creep at idle if setting for too long.

[MikeStang 247]

Rider,

1st start up is just fine pump gas 2 times and hit the key and She fires right up....it's after it gets up to 190 and you kill it and it sets for 5-10 min then it has to be put tonthe floor to start most times.

Coolant looks great no chunks or anything else ....intake passages look nice and clean too.....gotta find an ac water pump pulley now lol

[LoneWolf2U 136]

By chance are you using a carb spacer plate?

if not it could be causing the fuel to perk (boil) when warm after shut down.

[MikeStang 247]

That was exactly what i was thinking Mach, and no i dont think it has a spacer on it, im gonna have to take a look.

 

Mike

[MikeStang 247]

Well carb has a spacer on it, and the timing was set at 6* BTDC, so i bumped her up to 10....The car will get up to 182 then drop down to 165-170, then come back up, then go back down....This is sitting in my shop idling, still no coolant movement tho...gotta try to find an AC water pump pulley now.

Anyone got one for sale>?

Mike

[buening 63]

I honestly don't think an A/C pulley will help your cause as much as you think. It will increase flow slightly, but you should still see a good flow of coolant with a standard pulley. My 302 without A/C has a very noticeable coolant flow with the stock 20" radiator. Yours should too. I'd pull the pump and get a FlowKooler from Summit. While you have the pump off, inspect the coolant passages that are exposed.

 

FWIW just because you have a new radiator doesn't mean it didn't get plugged once you first fired the car up. I've seen it many times, because the previous radiator was plugged so they buy a new radiator only for the coolant passages to still release more crud into the new radiator. You mentioned your coolant is clean so it may not be an issue, but pointing this out for others who may be reading this thread for help.

[Max Power 74]

I honestly think that any water pump that can keep up the coolant flow at speed will not have a problem at idle.

[LoneWolf2U 136]

Well carb has a spacer on it, and the timing was set at 6* BTDC, so i bumped her up to 10....The car will get up to 182 then drop down to 165-170, then come back up, then go back down....This is sitting in my shop idling, still no coolant movement tho...gotta try to find an AC water pump pulley now.

Anyone got one for sale>?

Mike

 

What type of spacer?

I suggest using a 4 hole hollow type spacer over a soild style, it dissapates heat faster.

As for coolant flow, at those temps you will never see it.

Even at the 182 the stat is not open long enough to get it flowing because as soon as the lower temp coolant reaches the stat it snaps closed to rewarm engine.

You need to drive it and bring the temp up to 185-190 and remove the cap and inspect for coolant flowing past the neck.

[buening 63]

What type of spacer?

 

You need to drive it and bring the temp up to 185-190 and remove the cap and inspect for coolant flowing past the neck.

 

I'm not sure I'd recommend removing the radiator cap on a hot engine unless it has a pressure release lever on it

[1969 Mach1 14]

MikeStang:

 

I haven't followed this post regularly so I hope I don't repeat something somebody else said. From what I have read everything seems to be correct. When the motor was rebuilt, first, how much were the cylinders bored? For 351w, 0.030" is about all you can go without having overheating problems. Even at 0.030" if there was some core shift when the block was cast you can start having problems getting the cooling system to work correctly. Second, are both gead gaskets are installed correctly? I haven't personally seen the effects of an incorrectly installed head gasket but the motor will overheat.

 

As far as hard starting when hot, you are probebly right in suspecting the carb bowl is draining but verify you have spark just to rule that out. Also, during these hot hard starting instances you may getting "vapor lock". The fuel in the line from the pump to carb is boiling so it compresses rather than flows when the fuel pump actuates.

 

Lastly, again make sure you are using a high quality or high flow thermostat with a bleed hole in it. Ford's are hard on thermostats. The regular low end lines parts stores sell do not work very well and by themselves cause temp fluxuations.

[LoneWolf2U 136]

I'm not sure I'd recommend removing the radiator cap on a hot engine unless it has a pressure release lever on it

 

True, some saftey precaution should be taken in doing so.

But on these closed cooling systems, I always use a lever style release cap.

[MikeStang 247]

Alright, after increasing timing and checking carb spacing, "Which is a 2 barrel carb spacer on this 2 barrel carb" I also adjusted the idle mix screws and ran it a bit richer, because i knoticed at idle you could cover the carb, or shoot a little propane in the top of the carb and the idle would go up and the engine would smooth out a bit, this indicates a lean mix at idle which i was hoping could have been part of my problem.

So i went and drove the car, ans as usual it ran plenty cool at speed, then i got her home and let it heat up to 190 and shut it off, waited 5 min and she fired up just fine with out having to touch the gas pedal.

But as we all know as a car sits, after being shut down, the temp will climb because ther is no water moving...so when i started it up the guage was around 230 or so, but it came down to around 190, then becan climbing agin, so i shut it off and went in the house...i have not let it just run past 190, well mabe 195 once, but it was still climbing so i shut it off....This is really starting to piss me off.......Oh in response to one of the questions about heating the motor to temp then removing the cap.....I have several times let the engine get up to the 190 range with the cap off the radiator, and there is no coolant flow, it just sits there.....Think i am just gonna put a flow kooler pump and go from there, the pump the owner installed is one of the cast iron pumps, and it likely has the crappy stamped impeller, and its pretty much a proven fact that the stamped steel impellers are junk, partially because there are generally less fins on them as opposed to the cast iron impellers which generally have 6-8 veigns on them, I may just let the motor warm up to past 195, and see where she goes. Also in regards to the thermostat not opening all the way, because cool water is hitting it, im not sure this i totally correct, because at idle when it gets up to 190 the thermost would be fully open and stay that way because the water temp keeps going up, which rules out the possibility of the thermostat not staying open.

Oh as i said before when the owner got the car, there was NO thermostat in it, this tells me there may have been a problem they couldnt solve.

I have also considered that if they bored this motor more than 30-40 over their could be heating issues, so i have not ruled that out as of yet.

Mike

[MikeStang 247]

Also wondering why you said go drive it to get it to temp then open the cap, when letting it idle does the same thing...thinking your just suggesting it so the temp will get up faster?

Mike

[LoneWolf2U 136]

Yes to get temp up quicker.

might I suggest that while you have the waterpump off you use a hose to pressure flush the block out.

Look for same amount of clear water exiting as you put in from both sides of the pumps holes.

[buening 63]

I've read and didn't find the answer, but how exactly are you getting your engine temp readings? If it is a gauge, is it a mechancial or electrical and what brand gauge?

[1969 Mach1 14]

I am running a Flowcooler water pump on mine. In installed it to replace a stock water pump. I noticed no reduction in operating temps. The only physical differences between the two on mine were (1) stock was cast iron, Flowcooler was aluminum and (2) Flowcooler takes a stock imported aluminum water pump and pop-rivits a disk to the back of the impeller.

 

Actually I have seen a kit from Summit Racing that includes the disk and pop-rivits to modify a stock water pump.

 

Is the carb too lean throughout idle, transfer, and main circuits? A lean condition will increase temps. Head gaskets are on correctly? If they are stock fel-pro's do some research, you can tell by looking at the shape of the gasket sticking out of the front of the motor. If thats all ok, it might be worth while to check for a leaking head gasket, just to rule out that possibility.

[buening 63]

Yes, but you replaced a water pump that apparently was working correctly, no? Can you visually tell your coolant is flowing in the radiator? I stand by my opinion that you should visibly see water flowing through the radiator with the cap removed AND the thermostat open. I'm not trying to have him throw parts at it, but either his thermostat is not opening or his pump is not working correctly. I can't claim the FlowKooler works better than a new cast iron, but he apparently has one of unknown shape. He will have one with a good track record and shave a few pounds off the front end in the process.

 

I still question how he is getting his temps, as I've seen some wacky things occur with sending units that will give false readings. A secondary temperature source needs to be utilized, whether it be a meat thermometer pressed through the radiator core near the top and possibly bottom to compare, or invest in an infrared thermometer scanner. This way you KNOW the gauge is correct and that the motor is actually running at that temp at idle. You obviously can't do this while driving though ;)

 

Wouldn't a head gasket issue cause overheating at high speeds and not just at idle? I would think it would exist at all conditions. A blocked passage causes overheating at all speeds regardless of air flow through the radiator. The same goes with a lean condition, unless his idle circuit is too lean but his mains are fine.

[Pakrat 1,043]

Actually I have seen a kit from Summit Racing that includes the disk and pop-rivits to modify a stock water pump.

 

FWIW I did this mod to my stock pump when I replaced the timing chain and what not. I had to run 2 gaskets though to space it enough, I didn't want to grind the rivets down and risk it coming loose.

 

http://www.1969stang.com/mustang/forum/showthread.php?t=1889

[1969 Mach1 14]

buening:

 

Your right about the head gasket. My mistake. This long thread, I've lost track of when the heating problem is occurring. But with both water pumps on mine, at idle there is very little visible water movement when looking through the radiator cap with a warmed engine and open thermostat. And I am running a 160 deg. high flow thermostat as well as the largest 24" wide aluminum radiator Griffin offers for 1969 Mustangs. If that makes a difference. And actually, switching to that aluminum radiator was the only thing that brought temps down on mine.

 

I also still question the thermostat. The quality of todays parts seem to be you have to buy the high end stuff to get what was just average years ago. I can see your point with his water pump. I hate throwing parts at it also, but at some point you have to start installing known good parts.

 

On a side note high engine temps seem more common than not on these early Mustangs. I contribute some of this to heat not being able to escape the small engine compartments. The only Mustangs I have seen with absolutely no cooling issues have had old worn out low compression, low power engines.

 

Did I miss the radiator size that is in this car?

[buening 63]

4 core radiator but not sure if its a 20" or 24".

 

Yeah I'm running the high volume thermostat Mr. Gasket one like shown below, except mine is all brass/copper

 

http://www.summitracing.com/parts/MRG-4364/

 

 

 

He does mention the temps getting up to 187 and then dropping down to 160, which seems to indicate the thermostat is working however I've never seen one fluctuate like that. Typically it will get up to a certain point and then just stay there, as it most likely will need to be wide open to maintain the 180°. Something fishy going on there but can't put my finger on it!

[1969 Mach1 14]

I am running out of ideas. I know I originally had a 24" wide 4-core copper brass radiator in mine and it just would not do it. If ambient temps were 80 deg. or more the engine temp would just keep creeping up. It looked more than large enough but I guess it was not efficient enough.

 

Todays high flow thermostats look identical to the regular thermostats from years ago.

[MikeStang 247]

The radiator is a 4 core 24" unit, which should cool anything just about in fords line up for the 69 year model hahah.

The motor is pretty much stock, altho i cant say for sure, i can tell you it does not have anything over a stock cam in MHO, it idles pretty smooth and runs well......I richened the carb up, but it does have the autolite 2100 studder when running around 50, I can feel it but the owner says he feels nothing, BUT its running Cool at cruise speeds. I richened the air mix screws and it smoothed out some, but now it actually smells rich, where as it didnt before.

When i rebuilt the carb, it was trashed inside, there was literally what looked like sand caked into one side of the bowl....I had to soak that thing for 2 days in my dunk bucket to get it all clean,

I would love to get the little studder out, so i may rebuild the carb again, but i do not think that is the source of running hot at idle, since i richened it up and you can no longet put your hand over the carb or shoot propane in it, and make it idle up.

Safe to say i cured the lean mix at idle lol.

the little guages i have are made by Sunpro, i know they are not the best in the world, but the probe is stuck into the intake where the stock sensor was located. maybe i can take it out and try another guage, but have the feeling its gonna show the same thing.

I may take a ride tonight, and video the temp fluxciation when driving.

Mike

[MikeStang 247]

Ok heres the latest developments....

I installed one of the Mr. Gasket high flow thermostats, let it warm up, but saw no drop in coolant level when the thermostat opened, which in my opinion is WEIRD...I have one of the little funnels that you screw in place of the radiator cap, that you fill with water and let the car run and when the coolant level drops what you have put in the funnel fills it up all the way....Well what was in the funnell NEVER went down .....Ok so i let it sit in gear, and warm up to 210 degrees, and she kept climbing, but i did see some coolant moving around at Idle, thats a good thing i suppose LOL....Anyhow when you would rev the car in neutral and hold it there the remp started coming down, so i took it for a ride, and it immediatley in the first 1/2 mile cooled down to 170 and stayed there LOL....So when i got home i killed it and just sat there and thought about it a bit......Then i had a moment of clarity.....I wondered "What if the pulleys are wrong, since i did not install them and had no idea of what the dimensions were......The crank pulley is of the 3 bolt variety, so i was kinda assuming it was correct, i then looked at the gap between the water pump pulley and the crank pulley, i couldnt stick my finger in it so i decided to measure it with feeler guages.....Well there is 0.060- 0.065 in between the pulleys "is it just me or does this seem kinda close?"

I then grabed my trusty calipers and ran them all the way out to 6" and they were tooi small to measure the water pump pulley....So im now wondering how large the water pump pulley is supposed to be and what about the crank pulley, AND how much room should there be in between them....I figure about an inch or so, but i may be wrong.....Some help here please...

Mike