Nealio240z Posted September 10, 2007 Author Share Posted September 10, 2007 Well I tore into my engine this weekend and took off the heads. At least this way I could rule out the head gaskets... Or so I thought... The heads and the block both have a 1" hole for the water jackets, but the STUPID HEAD GASKETS only has one little 1/8" hole in them, blocking off most of my cooling capacity... come to find out that that motor was throttle body injected and they wanted to run it hot on purpose for emission control... What a load of crap... All that work for nothing... Thanks to all of you for your help. I couldnt have solved the problem without reasoning it out with others... Quote Link to comment Share on other sites More sharing options...
deja Posted September 10, 2007 Share Posted September 10, 2007 Well I tore into my engine this weekend and took off the heads. At least this way I could rule out the head gaskets... Or so I thought... The heads and the block both have a 1" hole for the water jackets, but the STUPID HEAD GASKETS only has one little 1/8" hole in them, blocking off most of my cooling capacity... come to find out that that motor was throttle body injected and they wanted to run it hot on purpose for emission control... What a load of crap... All that work for nothing... Thanks to all of you for your help. I couldnt have solved the problem without reasoning it out with others... Holy crap! Well I guess they accomplished what they wanted. Glad to hear you figured it out. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted September 10, 2007 Share Posted September 10, 2007 so! Im assuming,swapping to differant head gaskets DID significantly lower the operating temps??? Quote Link to comment Share on other sites More sharing options...
lbhsbZ Posted September 10, 2007 Share Posted September 10, 2007 I'm not sure the headgaskets were the problem....the reason for the small holes in the headgaskets towards the front and the larger holes towards the back, is to force the water to go to the rear of the engine....if the front cooling holes in the headgasket are large and provide no restriction, then water will go straight through the front ports into the intake manifold and back through the upper radiator hose.....without any coolant flow through the rear of engine..... When you reassemble everything, get a temp sensor in the rear of one of one of the heads and monitor that temperature vs the coolant temp at the thermostat....I think you will cook the rear cylinders. Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted September 10, 2007 Author Share Posted September 10, 2007 The hesd gasket doesnt have any hole larger or smaller than the others. The small holes in the gasket for the water jacket are the same size in the front as the back... I have two temp senders- one in the back and one in the front, both in the intake manifold. I havent got new gaskets yet, because I just pulled everything apart yesterday... I flushed the block and inspected the water jackets all around the motor and nothing was astray... If not the gaskets- than what else could it be? Its a 90's motor and I dont think ill find gaskets that are open holes for the water to flow through. - So I might have to punch my own... Has anyone else had this problem? Is anyone running the same set up as me? Anyone running a 90's motor w/ a carb, and not throttle body??? Please tell me that im on the right track........... Quote Link to comment Share on other sites More sharing options...
lbhsbZ Posted September 10, 2007 Share Posted September 10, 2007 Post a picture of the deck of your block and a picture of the gasket...I've got a stack of gaskets at the house for earlier motors, I'll compare them when I get home. Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted September 10, 2007 Author Share Posted September 10, 2007 Crap I dont have a web cam or digital camera @ work... Any block and heads from 1986-1994 should be the same as I have if that helps. ---------sorry... Quote Link to comment Share on other sites More sharing options...
Bartman Posted September 10, 2007 Share Posted September 10, 2007 I think the small hole in the head gasket is probably just a red herring. I think the most important issue has already been stated in this thread a few times. You need to ensure that the air is getting to, and flowing through, your radiator. Providing a "scoop" to the bottom of your radiator not only helps direct the air through your radiator it also helps prevent air from going under your radiator instead of through it. I experienced higher temperatures at speed when I "leaned" my radiator back, and I was able to get my temperatures back down by installing some sheet metal to prevent air from going below the radiator. This problem can also be compounded by thicker radiators that are more likely to resist air moving through them. As you stated in your original post it "heats up on the freeway. Runs fine around town". That sounds like an airflow problem to me (of course there are other possible candidates that were already covered in this thread), and the same symptoms that I had. Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted September 10, 2007 Author Share Posted September 10, 2007 K.. I hear ya loud and clear. To put it into detail -- why doesnt it cool down after freeway driving when im at an idle? And how come Im running a 160 thermostat and around town it runs around 210? shouldnt it be about 175?--- (im still gonna put a scoop under the car though) Quote Link to comment Share on other sites More sharing options...
v80z Posted September 11, 2007 Share Posted September 11, 2007 Mine runs 205 210 all the time night day highway around the block. I think it is a function of poor gas in this modern day and age and fuel delivery in non atomized state. this can cause a blow torch effect where the fuel is not fully combusted at or near tdc and continues to burn out the exhaust port thus heating the engine. I have worked on my issue alot and have worked with Don at: http://www.4secondsflat.com/Demon_Tuning_Guide.html His main suggestion to me was to get the carb and timing tuned correctly. Utilize a quality intake and add a 4 hole carb spacer to help direct the mixture down where is needs to go. Without a 4 hole carb spacer the fuel/air tumbles down past the butterflys in varying concentrations. I am not quite there yet but continue to work on it. BTW his qwork on Mighty Demon is very extensive. To this day when traveling at 60mph at 3000rpm I can still hear a "burble" ever so slightly in the exhaust note. it is a great free read and his dowwnload is well worth $10. At this point I have come to accept 205 - 210 as normal. I am sure you have run a pressure check on you water system. And of course sealing around the radiator and all other suggestions are well worth investigating. Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted September 11, 2007 Author Share Posted September 11, 2007 Another question--- How many cfm does a ford tarus fan put out?? (single speed). And how many cfm of flow is needed for a sbc to keep cool? Could my shroud be keeping air from flowing through the radiator while driving? -It covers most of the radiator, -is it acting as a blockage??? Quote Link to comment Share on other sites More sharing options...
v80z Posted September 12, 2007 Share Posted September 12, 2007 Taurus fan is rated at 3500 cfm slow speed and 5000 cfm hi speed Quote Link to comment Share on other sites More sharing options...
COZY Z COLE Posted September 12, 2007 Share Posted September 12, 2007 Another question--- How many cfm does a ford tarus fan put out?? (single speed). And how many cfm of flow is needed for a sbc to keep cool? Could my shroud be keeping air from flowing through the radiator while driving? -It covers most of the radiator, -is it acting as a blockage??? Are you telling us now that you only have a single speed fan or you only have the low speed wired on a two-speed fan??? LARRY Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted September 12, 2007 Author Share Posted September 12, 2007 I have a tarus fan with two wires coming out of it---Im assuming that this means it is a one speed fan... It also has a shroud. I think the shroud is too close to the radiator and causing blockage... Is it enough flow to keep it cool? Quote Link to comment Share on other sites More sharing options...
COZY Z COLE Posted September 12, 2007 Share Posted September 12, 2007 I would strongly suggest the 3 wire 2-speed Taurus fan. You can get it from a junk yard at around $25. Have a read... http://forums.hybridz.org/showthread.php?t=99700&highlight=Ford+Taurus+2-speed+fan LARRY Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted September 12, 2007 Share Posted September 12, 2007 I think the shroud is too close to the radiator and causing blockage... Is it enough flow to keep it cool? The shroud should be as close as possible to the radiator, if not sealed to it. It will still flow enough air at speed. I sealed mine with a seal I bought from McMaster-Carr, # 2 , I think part # 1120A821 but it depends on the size of your gap. Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted September 13, 2007 Author Share Posted September 13, 2007 Ill give it a try this weekend and let ya know what I find.... Quote Link to comment Share on other sites More sharing options...
HLS30-08077 Posted November 6, 2007 Share Posted November 6, 2007 I had major issues with cooling on my 240Z until I did the cowl induction hood. I made it from some spare steel I had around the shop. I roughly gave the air somewhere to flow to after it flowed thru the radiator. I now have a http://www.griffinradiator.com/ and it looks as beautiful as it works. I just had to make a custom cross-member seat and top bracket. It's 19" hi X 24" wide X 3" thick. And a cross flow design (side to side) Cost me about $300 and it was real easy to polish up. Picture to come after I finish the top plate. Dave. Air flow “to†and “through†the radiator seems to suspect in our S-30 Z cars. The results of the recent wind tunnel tests show the Z car definitely shows signs of having issues in that area. As you, I chased my tail trying to get my V-8 Z to run cooler as it wanted to run warm on warm days, even down the freeway under light to no load where air "should" be flowing through the radiator. In an effort to keep it cool I employed the following mods, and alterations. 1) Blocked off the internal block coolant bypass and redrilled the plug with a smaller hole. 2) Reduced the water pump impeller to housing clearance. 3) Ported the water pump itself, thermostat housing outlet and intake manifold coolant ports. 4) Added a backing plate to the water pump impeller. 5) Port matched the water pump to the block. 6) Over drive pulleys in two steps. 7) Colder thermostats. 8) Special high flow thermostats 9) Higher pressure rad caps. 10) Burping the cooling system using a few different methods. 11) Stock car racing radiator. 12) GM Radiator from JTR. 13) Higher flow cooling fan, (I should’ve went to a REAL fan as I was still using inadequate cheesy cheap-o fans). 14) Removed the license plate from in front of the grill. 15) Removed the grill. 16) Sealed off the holes in the radiator core support . Now the only mods that made ANY noticeable improvements whatsoever in the engine running cooler were the mods that improved air flow “to†and “through†the radiator. All other mods to improve coolant flow made no difference. With what I learned from the wind tunnel testing recently, I feel quite confident that if I would’ve employed some of the principles learned from the wind tunnel testing, the overheating issue in my car would’ve been 100% solved, at the time, I just had no idea what else would or would not improve air flow “to†and “through†the radiator in an S-30 Z car. That’s my $.02 Quote Link to comment Share on other sites More sharing options...
Nealio240z Posted November 12, 2007 Author Share Posted November 12, 2007 Guys. Thanks for the help. ALOT... I ended up going through the whole front end, as follows... I sealed the radiator to the frame with foam and aluminum foil tape (cheesy but worked) then I fabbed a piece of metal with a 3/8 hose lining the top, to seal my frame to the hood when it was closed. thus forcing more air in the rad. Then I relocated my front license plate to free up some air flow. Then I made a sheet metal plate to seal my air dam to the bottom of the radiator, I sealed off all of the open holes that would allow air through them in the front frame rail that the rad bolts to... All of these mods fixed the problem and forces enough air through the rad to keep me running about 185 degrees... Finally I can start to enjoy the car and drive it as intended... thx Quote Link to comment Share on other sites More sharing options...
icewtr Posted November 12, 2007 Share Posted November 12, 2007 Ok .. Spo when i first did my 383 i wanted a 160 thermostat .. thinking it would run there.. but no car was running about 190... i moved my temp guage to the rear of the intake and car is now showing 150.. thats your larger hole in the gasket at work.. .. so some old man told me .. and i mean old as in way older and wiser than me in the way of knowing alot more than i do about anything ...lol said the car can not maintain a 160 thermostat .. the water leaves the radiator to soon and can not cool down i moved to a 180 and the car sits right there all day long .. and i live in the desert where i am way over 110 outside sitting in traffic .. i have the stock radiator from a 70 240z in my z the 2 row .. i do also have a large hood scoop facing forward but that is why when on the freeway car drops to about 150 on the guage .. and i also am oly running 3.55 gears and a 700r4 tranny .. bye the way the tranny cooler is mounter under the hood above and to the front of the radiator .. kinda strange but works verry well .. Quote Link to comment Share on other sites More sharing options...
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