still getting temp creep, now what?

[EMSjunkie]

I have been trying for the past several months to figure out why I am getting temp creep at hi-way speeds. :?

it cools down pretty quick at low speeds with the elect. fan on, but the temp creeps up at hi-way speeds. will get up around 195-200* on the guage. haven't hooked the a/c up yet, don't wanna run the a/c if the temp is not within "normal limits".

I am running a 16" Spal curved blade fan, a shroud, 180* t-stat. nothing in front of the radiator to block flow, Walker Z-series radiator with a/c condenser. I have opened up the side panels to allow heat to escape. all to no avail.

I did change t-stats this weekend. new Stant 180*, drilled a 1/4" hole in it before install, added a bottle of Redline "Watter Wetter". it dropped the temp to 190-195* on the hi-way. but still too high to run the a/c, right :?:

I feel like it is an air-flow problem, since it cools rather well at low speeds with the fan on, but heats up at hi-way speeds. there should be enough air flowing across the radiator at hiway speeds to not need the elect. fan, right :?:

I have stainless steel upper and lower hoses, and heater hoses.
but it did the same thing with standard rubber hoses.

I give up, I have tried everything I know, now its time to stop and ask the brain trust here.



it seems to be worse when the ambient temps are high, in the upper 80's to mid 90's



Team Smart needs your help  

Vance

[Dave]

Timing maybe :?:  :?:  :?: Most all the problems ive ever had with cooling have been at an idle. I was always under the assumption that heat at highway speeeds was more a timing  issue.  The other think is moving the water too fast thru the engine. Then your not letting it stay there long enuff to do any cooling thus the engine heats up and eventually the water cant be cooled anymore either. my 34 had a walker and my 32 had a griffin .. both ran 180 with full hoods and 190 at louisville when it was 105 degrees. Of course i was running crate engines that were all new and had clean water jackets too.
Dave  

[sirstude]

Timing will do it, but the other time I ran into this issue was when I had a new radiator made for my Studebaker.  It always ran 160 on the road, would heat up on the hills and then cool back down on the downhill stretch. The new radiator had smaller top and bottom and probably cost me 2 quarts of coolant and it always ran around 200 after that.  I think the total coolant capacity was just too small to get rid of the heat.  Never could prove it, but the new owner put bigger tanks on the same core and the heating issues went away.  

Doug

[EMSjunkie]

Thanks for the info.
I don't think timing is an issue, I have set the timing with a light, with a vacuum guage, by ear, no difference. if I "tweak" it too much, it really heats up. or won't run worth a crap :?

flow too fast. possible  

Vance

[Charlie Chops 1940]

I have a 195 stat in the '40 Chevy and a "no-numbers" temp gauge, just a low at one end and high at the other. Normal is to the left of center. When the a/c is on going down the highway there is little to no heat creap. Traffic will raise it some but it never spits anything out.

Don't over analyze the situation. Getting a reasonably stout engine to run at 160 or 180 is somewhat unrealistic given the characteristics of todays fuel. Current GM systems run at 200 or more.

Charlie

[donsrods]

Something that happens that many people refuse to believe is that airflow can go around the radiator rather than through it.  The design of some engine compartments creates a high pressure area at speed, and new, incoming air can't get through it.

Cars like '40 Fords seem to be the most common offenders.  What kind of car are you talking about here?


Don

[EMSjunkie]

Its a 34 Ford "replicar" from the wonderful (choke) folks at Innovative Street Machines dba "Street Beasts"

not really a "stout" small block, mild cam, chrome goodies, etc. nothing really major. bored .030 over, some mild porting and polishing to the heads. normally aspirated, Demon 625 cfm carb.

I am kinda curious about the timing issue, is it too advanced, or too retarded  :?  that could cause the temp creep :?:
I have tried to block the air from going around the radiator, at least on one side. I dunno :?

thanks for the help

Vance

[CQQL33]

Personally, I do not feel the temperatures you are getting are too high.   Water boils at 212 F.......but your radiator has a pressure cap (?) that will bring the boiling point of water over the normal, sea level boiling point.  When you add any additive to the water the boiling point goes up higher.
I have a '33 Ford coupe but I have louvers on the hood sides.   In the hot weather, about 95 degrees, My gauge reads about 200 while idleing through the fair grounds during a car show, 5 mph at best through lots of people.    When I first got it on the road, I installed a 165 F thermostate.   The car would warm up to the 165 temp, then cool down slightly, then warm up to about 200 degrees.    When out on the highway, it would cool down, at speed, and get down to 170.     I then installed a 185 degree thermostate.     Now it runs at about 190 to 200 degrees most all of the time during the summer months.    This seems perfect for the tune on the engine.   A lot of the new cars run temperature as high as 220 degrees without any concerns.    I would not worry too much unless the thing boils over.    
Rich

[UGLY OLDS]

Fought this FOREVER on a '39 Ford Standard... Car would idle at 190* in the driveway at 90* ambient with the air on for about 45 min with no issues...Drive it around the subdivision...temp drops to 180*..( Stat temp) ..Drive 2 miles on the highway...220* & climbing.....Park on the shoulder..Let car idle ..190*...AAAAARRRRGGGG :!:
 Finally got angry..( Yea,right )  & used light cardboard & duct tape to seal the front of the radiator to the grille shell...Top..Bottom ..Sides...No air coming in the grille could go anywhere but through the radiator...VOLIA :!:  :!:  Problem solved...  The little rubber pieces on the top on the Ugly Olds radiator support that seal it to the bottom ( underside) of the fenders were worth 15* on the highway..Remember..Air in the grille area is going to take the path of LEAST resistance to avoid the radiator core...Over ..Under & Around..look at the little foam seals on a late model....Sounds crazy but it woiks....    

[Mikej]

Heating up at cruise speed could be because its to lean. Caused by too much advance or carb to lean. What temp does your fan come on? Mine doesn't come on until 205 to 210. BBC  I use a 17lb cap to keep the water in the radiator. When I first bought the car it would go to 230 and up. I did all of the things suggested here. I also put on a high flow Stewart pump. The hotter outside it is the warmer it will run. The space for the radiator just isn't big enough. I also have a full flow thermostat from speedway. It has 4 bypass holes. This isn't the best when temp outside is 40 or lower. The motor never gets up to temp. If the water is staying in the radiator you are probably all right.

[Charlie Chops 1940]

All good points. Sealing the leaks around the radiator is very important as some pointed out. Louvered hood tops and/or hood sides help a lot. For some reason completely open sides offer little improvement - airflow slows down through the radiator I think.

Charlie

[EMSjunkie]

Thanks Guys, all very good information

I'm gonna try the lean mixture / too much advance first. I think I have 70's in the primaries, but not sure :? may go up to 72's or 73's

will try to back off the timing just a little.

I did not remove the hood side panels, just took out the perforated steel I had behind the flame cut-outs, have pretty good air flow out the sides with the fan on.

I'm a firm believer in the K.I.S.S. theory (keep it simple, stupid)

also gonna try to plug the gap on the drivers side of the radiator too.

surley its something simple, just too complicated for my simple mind

updates to follow..........



Vance

[t-vicky]

My 40 Olds did this very thing.  Could sit in the driveway or cruse around town 35-40 mph it would sit on 180  Get out on the hiway over 55 & the temp would go up 200-220 Slow back down to 40-45 & the temp would drop.  
Problem was -- a full Walker shroud with a 16" elect fan mounted to the shroud was blocking air from coming thru the radiator.  My upper hose is in the middle so I cut a slot about 3" high & 6" long on each side of the shroud at the top. Hinged them on the top with a small piano hinge.  Cliped a small tire weight on the bottom edge.  Fixed the problem. I can see them thur my hood louvers & they start coming open at about 25 mph.

[EMSjunkie]

My 40 Olds did this very thing.  Could sit in the driveway or cruse around town 35-40 mph it would sit on 180  Get out on the hiway over 55 & the temp would go up 200-220 Slow back down to 40-45 & the temp would drop.  
Problem was -- a full Walker shroud with a 16" elect fan mounted to the shroud was blocking air from coming thru the radiator.  My upper hose is in the middle so I cut a slot about 3" high & 6" long on each side of the shroud at the top. Hinged them on the top with a small piano hinge.  Cliped a small tire weight on the bottom edge.  Fixed the problem. I can see them thur my hood louvers & they start coming open at about 25 mph.

Very interesting

I too am running a full walker shroud. may hafta try that trick, Thanks

leave it to a fellow Jayhawker

just a quick update on what I did this evening:
re-jetted the Demon. had 66's in the primaries, put 70's back in
retarded the timing about 4*
stuffed a towel (don't tell Debb, but I stole it from the Powder Room) around the radiator.

went for a little drive, ran around 185-190*, but the ambient temp was in the upper 70's low 80's

guess I'll hafta wait till the ambient temp gets back up in the 90's

thanks to all for the help / ideas. mucho appreciado

Vance

[sirstude]

Bring it up here, been high 90's low 100's the last couple of weeks and another week of the same at the least.  This is August weather, not July type.  It would sure test your car though Vance.  Also, remember, too retarted on the timing will make them run hot too.

Doug