I have had this POS for a couple of years now. The engine was overheating and blowing water out the overflow. I thought, blown head gasket. Well it was sort of, but mostly it was the eaten up head that wouldn't allow the head to seal properly. I also had another block bored because what I had needed rebuilding and I wanted a fresh engine.

The problem was that the cooling system would pressurize and blow the water out of the system and overheat! I tried a couple of heads from the junkyards but all of them had been eaten up pretty well and the gasket wouldn't seal. I bid on a realy nice head, got it in and checked it out and stuck it on. Well I was still getting the bubbles in the radiator coming out the cap hole. I finally pulled the head off the last time and found that the number 1 cylinder had some pitting and it looked like the water was seeping in there but also being pushed out when the engine was running.

I got my old block and had it bored then just transferred the parts to the just machined block. I built it, put it back in, connected everything, poured water in. I started it up and the bubbles are still there. They look like bubbles that might have a bit of exhaust gas in them. They just keep on coming out, never stopping. Eventually the system pressurizes and blows the water out and it overheats.

I got the radiator cleaned out and it has a new water pump. I just have been racking my brain trying to think of where and how these bubbles are getting in the system. It has to be something periferral, at least I think it does. I am ready to shoot it. I want to drive it so very bad, but I can't.The head is basically new, the block deck was milled flat I am getting the same problem with the engine setup as with the other. That is when I start it up. with the radiator cap off, I am getting bubble coming out of the cap hole. It never stops. the engine overheats after 20 minutes of idling and blows all the water out. Freeze plugs are sealed too. Somthing is forcing air into the system somewhere, but I am at a loss.

Any help would be very much appreciated. Suggestions, hints, even Miss Cleo. If you need more specifics, please ask.

Thanks
Russ Lawson

:(

well... it's 2am currently

i read your thread... i'm dumbfounded...

i'm sure i know why

but i can't think or answer right now LOL

i must be tired, but tomorrow i will answer ;)

promise!! hehe

well... i've been thinking about your problem all day....

about the most i can come up with is...

it's not bhg'd... more you have a split or leaking water hose which is sucking in air.. therefore constant bubbles?

have you burped the car?
are you sure it has a bhg?

have you done

• leakdown test
• compression check
• block check

let us know how you get on :)

hello,it maybe a leaking hose this would more likely leak coolant than suck air in.is the waterpump actually pumping,even when you do replace a waterpump brand new there may be air in the pump preventing the water from ciculateing coolant thru the engine.sometimes a vacume pump is requred to get the air out.my other suggestion is that the thermostat is not functioning correctly preventing the flow of the coolant thru the waterpump,thus the system becomes preasurized and extremely hot and spitts the coolant thru the overflow and out into the overflow tank.if your rad is good you've covered all the other bases milling the block,milling the head at the same time making sure the surfaces are true and using brand new metal head gaskets .also,have you had these blocks magnafluxed along with the heads there may be a minute crack somewere causin this irritating endevor.thats all i got for now, i hope this helps.being as thorough as you sound i'd immagine you'll figure it out.if not i'll try to brainstorm a few fresh ideas.have a less frustating day,and don't let that crap defeat you.

^ thanks for the additional suggestions heh

i should be the bhg expert considering i've killed 4 LOL (crappy locally made ones :( )

i think i've seen almost every symptom there is for bhgs... but the above really had me for a while lol

man, the more i look at this post the more it seems like the block deck surface and head deck surface are not mating correctly,the reason i say this is because you say you see exhaust gas leaks ,you also say that it seems like water is getting into the block. check the valve seals,if this is okay then make sure the blocks deck surface is machined to factory specs and also that the head deck is machined to factory specs,then with a new metal head gasket slap that onry thing back together use arp fasteners.if you've done all this correctly then all you have to worry about is the stuff i mentioned to you in my previouse post.i'm not assuming that you haven't done this correctly, i just want to make sure you have the right information.i hope this helps, if it doesn't help then i deserve 900 lashes with a wet noodle.

Hmmmmmm...I sure do appreciate all the suggestions. I did not have the block magnafluxed. I have done work on other Toyotas and while I have seen the blocks leak on the outside from rust below a freeze plug or a stress crack, I have only seen the cylinder pitted just once where it was leaking coolant once and that was my last 7mge engine. The mating surfaces are flat and the guide pins are not too tall and the head bolts are not bottoming out. I feel good about that mating surface.

What I don't like is the way the waterpump impeller is turning. The fan is turning the correct way to pull air through the radiator, but the impeller seems to turn backwards from what I would think as normal. Most people mechanic friends I have asked about this say it looks like it should turn just the opposite from the way it is turning.

If you turn the waterpump over and look at it from the impeller side it turns counter clockwise as it should with the way the engine turns over, clockwise.........with me still?!?!?!?!....lol. Most mechanics think the impellers should turn with the leading upper edge first, cupping the watter and forcing it to move. Instead it looks like the back side of the impellers are pushing the water away. They are arced and this way looks like it causes cavitation when it spins and very little water movement. I looked at a bunch of water pumps for the car and that is the way they all look.........so, anyway it just seems weird.

Now I have an electric fan on the newly acid dipped radiator, but I didn't have a thermostat in it. Well there was one in it but hollowed out. Is this one of those cars that needs a thermostat to slow the water down through the radiator?

If I drive it around town for a little bit, it seems to run a normal temp, but as soon as I get it on the freeway, it overheats. Should there be a shroud under the car from the airdam to the front crossmember? Would that help more air go through the radiator at higher speeds and keep it cool?

I have never had a problem with overheating like this car. I really like it, but I am taking more and more drugs to help me not drive it off a cliff, well, into a swamp down here in Louisiana..........lol.

Thanks and sorry to be so long winded, my kids think I talk too much also..........sigh.

Russ

try putting a 180 degree or 192 degree thermostat in,it's cheep and easy and worth a try.i'll bet at this rate that your thermostat set up is your problem,it will tops cost you 16.00 dollars and at most an hour of labor.without the thermostat the rad does not have time to cool the water .after all an easy fix is the best ,if it is possible.see if it's possible ,laters!

Yes, there are airdams on the underside of the car, but the car has a grill that allows plenty of air through, but it's worth getting them to force the air where it's supposed to go. Yes, get a thermostat, it may help a lot on this. Also, I know that water constantly goes through the heater core, so there may be air trapped in there, I know my bro had problems on his car getting the system to release all the bubbles and fill with water after he changed the engine.

Also, change your radiator cap. It holds the pressure in the system, and is spring loaded to allow it to vent to the bottle, and they do wear out. I think your water pump is fine, if you've looked at a bunch and they're all teh same, it should be fine, plus I don't know of any years that had backwards rotation on the fan/pump.

Also, is your electric fan one with a fan shroud, if not, that could cause yu to overheat as it will just suck air from around the fan and not through the radiator.

I'm outta suggestions, but if you suspect it's the HG, do a compression and leakdown test and at least get that out of the way and make sure it's not that.

and i grow even wiser,i love this place!

Well, I got the thermostat and drove it around a bit last night. I almost thought it was cured but it started tooverheat again during the drive.

The fan has a shroud, but doesn't cover the whole radiator. I need that row of two fans that is supposed to come with the radiator originally. It is getting too warm where there is now air flow. I think I will try making a lower cover to close th underside off and force the air to go through as much of the radiator as possible.

I do not think it is the head gasket. I just rebuilt the engine and like I said before, I feel confidant in that area. Now I may try to bump up the torque number like I saw "Supra Girl" (supra girl music here).....lol. But it torqued down evenly.

Like I said before, I don't like the impeller setup on the water pump though and thinking that it may be causing some of the bubbling in that area. I did notice a difference between makes of water pumps though. Some had deep blades while a few others were shallow. I suppose I should break down and buy the proper TOYOTA pump, $95.00 ouch!

Keep up the suggestions as they are what is keeping me motivated to continue with this......................thing.

Thanks
Russ

Those fans on the side are for the A/C system, and they never come on unless your A/C is on (at least on my car). I'm honestly starting to think it's the radiator now, since the stock units are copper and are prone to clogging (had the same problem in my toyota truck). Replace it and see what happens, couldn't hurt, though it's harder to get a really hot heater in the winter with a really good radiator.

I haven't used them yet, but someone posted the link to cheap supra parts, and they have a water pump for about $70

http://www.trademotion.com/partlocator/ind...m?siteid=213747

I'm doubting it's the water pump though, as putting the thermastat in it fixed a lot of it, which means it's moving the water plenty fast, and the thermastat slowed it down so the radiator could work.

http://www.ddmcse.com/turbo/images/pump1.jpg

http://www.ddmcse.com/turbo/images/pump2.jpg

for online reference . i have comments but can't post em right now

lemme say this for now

been there ,done that .

replacing this pump wasn't the answer for me either

you mention boring the blocks but what about surfacing the block(s)

what block got surfaced what block didn't?
are you using a metal gasket ?
could you have switched hoses going to and from somewhere ? kinda sounds like one hose is pushing when it should be pulling ..thats assuming it's not a bhg .
i have had my car for 10 years . i struggled with the same problem for about 60k miles . water pumps hoses radiators you name it , sensors swicthes anything i could think of finally she quit .
i swapped engines , and blew another gasket after 10k miles this was a remanu from japan . went with the metal blew that one in less time and had finally had it . i resurfaced the block by hand . had the head surfaced by machine and then did the head by hand . the two parts are beyond smooth . can you say badda bing ?

i've dealt with 4 bhg's on two different supras ....... they really suck .
flat and smooth

the picture makes the flaws easy to see but with the human eye the flaws are not easy to see and you can barely feel them .
i know it looks like grand canyon , but you can see the difference that the lapping tool made .
when i got the head back from the machine shop the guy there thought i was nuts for touching the head after he finished it . but the head looked like it had grand canyon all over it and i could feel it too . lapping the head made a big difference.. hand beats machine

one thing i've always thought about but never looked into is the pipe that runs along the entire block- exhaust side
http://www.ddmcse.com/turbo/images/block.JPG
it's coolant, it's a level pipe .. i just wonder what happens inside that pipe and whats stuck there or how plugged it could get .like i said i never looked at mine but it makes you go.... hmmmm

Well the waterpump pictures are appreciated. They all are the same I guess, just seems weird though. The mating surfaces on both the head and block were machined and very flat. I tried a few heads that had the water channels eaten out by electrolisis and that is where they never sealed well enough and leaked. This basically new head has no pitting nor any irregularities on the surface. It was checked before I bought it so I don't have first hand knowledge on actually seeing the checking being done.

The block was machined by a shop I regularly do business with, but no one is perfect! I don't seem to be losing water anywhere, it just doesn't seem to want to stay cool! I started with the fan and new fan clutch and a fan shroud. This shroud was from an older car and no electric fans for the A/C, but I don't have a compressor right now anyway. The fan clutch would run fast when it was cold but would slow down the hotter the engine would get. Sitting there idling it would eventually overheat.

With the electric fan, one big 16 incher, idling it will not over heat, but the side it does not cover does get hot. I thought driving it around would get air through that area so I tried it. Around town, not bad and it is hot down here in Louisiana, it managed to stay normal on the guage. As soon as I get on the freeway though the temp starts climbing. If I turn the heater on high, it doesn't go up as quick but still does go up. When I return to stop and go driving, it kind of stays where it is but slowly climbs, never drops.

The radiator is about a year old, aluminum, single core, 1" cores. I checked the parts house and the turbo takes the same radiator. There is no blockage of air from the A/C parts in front of the radiator other than normal. I am not sure about the smaller hoses running to various parts on the intake, but they will only fit at the places they go to. I replaced the heater core last year too, it was leaking.

It seems that the cooling portion on these cars is marginal at best. I know up north it might be better and maybe the car wasn't designed to cope with the heat down here, I know I am not!!!.....lol. I will keep working on it. I will find a smaller fan for the open side of the radiator and try to seal the bottom off between the airdam nose to the front crossmember.

Speaking of the water tubes running the length of the block. At the back corner on the exhaust side the is a port that is blocked off with a rubber cap. I don't see where it could go to. The heater hoses seem to go to the right places. Just wondering.

Thanks
Russ

i got the same cap off thing . blew it once a long time ago when i first got this car .

is it actually overheating still (water gushing the whole works) or is your temp gauge going crazy and/ or making you crazy ?

i think 20 minutes with the cap off is going to cause the water to blow out .
i don't trust my stock temp gauge and i sure can't trust yours .

what other over heating signs do you have ..

how about the extra water bottle up front is that pissing out onto the intercooler?
with the current setup has it actually over heated or maybe you have bhg paranoia (hey i've been there and i'm still getting treatment)

Well, Iput some water wetter in the system and am going to drive the car towork for the first time in a lot of months. I am not losing water when the engine isn't running too hot. When I do lose water, the guage has pegged or close to it and it blows it out the overflow bottle in front of the A/C condenser/evaporator, what ever that radiator looking thing is called. I can hear it boiling in the system and the bottle bounces all around while throwing up water. I am probably going to try a dual fan setup later on. I have one 16" fan and can't find one small enough to fit next to it, about 8" would be just right. So 2 twelve inch fans may be the way to go.

I guess with the engine over heating on me lately, many out there would think that I should have a bhg by now, but not yet. I haven't been pushing it and let it cool down naturally.

I think I need to work on flow through the radiator at speed. I have said it before though, I think the cooling system has been marginal at best. I think the radiator is too small and I think the pump lets the water stay too long in the block. That is a long block and maybe the water jackets weren't designed large enough, I just don't know. I raced a Toyota Celica 22R engine for quite a few years with rpms running up to 7800 prms and the engine always ran cool. Large radiator and good flowing system and no fan shroud! Go figure.

I hope I make it to work without getting pissed at the steam coming out of it again. I will let you know. The cap is pretty new and I will check the ignition timing tomorrow. I set it to where it just stopped detonating and then retarded it a bit more, just a bit. Who knows maybe that is my problem or part of it.

Later
Russ

i would only use toyota parts for the cap and thermostat .

i tired to stuff 2 elect fans onto mine too .. i took off the a/c fans and all the a/c i use (1) 14" perma cool elec fan and a 4 inch shroud made to fit around the fan , smack in the middle , i'm using a fluidyne radiator . i drove around yesterday for hours up and down all kinds of hills . it's seems great however i can never really relax...i always watch the gauge . i crap my pants once the temp gets to 190 degrees . the car seems to be a cold blooded beast . after the sun goes down and the temp cools off it will drop to 160 degrees . i get no bubbling or spitting but i refuse to run at water temps of 200 plus .. if it gets or starts to climb over 190 i start taking cool down action . use the heater--- coast all that patented supra cool down stuff . i'll pull over and chill for a second , i just can't handle driving above 190 .
you got some horse power behind the thinking on this problem hopefully we'll come up with the solution .

do you have a service manual ?

http://www.cygnusx1.net/supra/library/TSRM...M/co/CO_01.html


kinda funny the cooling system is the smallest section in the service manual

I do have a service manual on cd. I got it on ebay and you are right it is a very small, uninformative section! I did check the timing and I did have it at around 18 degrees advanced, but no detonation. I moved it back to 12 degrees to see how that does. I will probably lose some power, but maybe it will cool a little more, but it goes against my thinking. I did notice where it did say that if the timing was too far retarded, it might run hot, but they didn't say how much was too much.

About the fluidine radiator, how much was it and is it basically the same thickness of the stock one. Mine is aluminum and single core with plastic top and bottom. I wish they made a double core radiator same size. I would have bet money the turbo would have been that, but I was wrong! I don't have a numbered temp guage, but it runs for quite a while at about 1/3 up the guage. When it starts climbing to halfway I do the same as you, but I sure hate turning on the heater! I am going to make a piece that fits under the car between the airdam and the front crossmember to see if that directs more air to the radiator. I may even make a small scoop to pick up a little more air, but I will have to see about that.

My aftermarket Griffen for the race car was only $170.00, so I might just see if when all else fails, making one of those fit. They make several width and height combinations, maybe one will work if nothing else here does.

Thanks for all the comments and hints. It sure is a nice car to drive and with the better flowmaster muffler it sounds great too.

Russ

i forget exactly how much it was for the fluidyne
i think it was 500 bucks ... slides right into place using existing hardware

since you don't have a air/fuel meter you can't tell if it's running lean

That seems pretty cool, mine runs around the halfway point all the time after it warms up, and water never spews. :blink:

That radiator sounds funny to me, I don't have plastic ends, though my bro's T/A does, and he had to replace it because when it did blow it was nasty. Also, try putting the old mechanical fan on it, and replace the fan clutch, it sounds like it was going out since it slowed down when it got hot.

Fluidyne radiator with fans:
http://www.suprastore.com/copa.html

the more i think about this , the more i would like to know whats inside the long pipes on the side of the block .

the temp gauge should be around a third of the way from the bottom

if you in the market for a new rad ebay has some geat deals on koyo racing rads that are all aluminum construction,i got mine from drift factory warehouse for 364.00 with shipping and a free item of your choice.this core is stout and a tight fit,but it does fit unlike the peice of tissue paper the stock one.you can use all of you old hardware too.

also this koyo rad is normally 530.00 dollars,get a great deal now.you'll look at your stock one next to the koyo and wonder what the hell toyota was thinking putting that oem peice o crap in in the first place.

The pipes along the side of the block are clear, but they aren't really needed except the the fact that they are part of the piping for the heater core and it seems like you really need that to help cool the damn thing down!!!! Only 98* outside so 85 feels almost cool.......lol.

I am going to put a Griffen racing radiator in it like I used to have in my Celica race car. They make a 26x19x3 double row aluminum radiator for $160.00 I will have to make the mounting hardware for it, but it is nothing I haven't done before. It is an inch taller than the stock radiator but more than twice the cooling power and...........the price is very right for me ;-).

It runs so marginally hot that I know this will fix it. I guess it never gets hot in Japan so that tiny thing up front was good enough there. Even still though, it seems that it would almost always have to be in the 50's to keep the car cool enough to have fun and drive without worry........maybe?!?!?! The car sounds too cool to give up on and there aren't any around here or there are but they all have a...BHG.....arghhhhhhh....................won't say the three words... ;) .

Later
Russ

i've held onto mine for ten years and poured cash ,sweat and tears into it for a reason .

i use a 160 degree thermostat from toyota

DDMCSE.....lol!! That is a very good website. Nice history of your two cars. Very sad about the first one. I even liked the touch about being faster than anything in Bossier City.........lol, that was good. It sure is a sad event when these beautiful engines have to be upgraded so much to make them reliable. That is a great looking radiator, but way to much for me to spend, the wife would kill me more than she already has!!!

The turbo has always been a dream, but was just hoping to get this one done, drive it then sell it to upgrade to the turbo. Well, maybe someday. I went with the 180 thermostat but had the option of the 160. Have you tried both and could you tell a difference? I mean did it keep it cooler any longer or run too cool. I really want to know just how good that Fluidyne radiator turned out. I am sure it is a double row aluminum rad. Can you run it as hard and as long as you like it and have it still maintain its cool? Tell me about it. Thanks

Russ

when it gets warm there was no difference in the temp between 180 or the 160 . I've used aftermarkets too
but it's nice to see it chill to 160 once in a while like at night
i figure why wait till it gets to 180 to open we know where this is going so open at 160 and get to work and thats why i stick with the 160.
i haven't spit a drop of fluid in years . do i beat on it and get it hot .. you bet .
in fact last years dyno runs were done after an 1hr and a half highway drive to the place
i haven't seen the hottest temp she'll go and i won't find out what that is 210 is /was tops i've seen on this gauge ..btw the stock shows normal at this temp
my gauge shows green from about 180 to 240 my head guy told me it should be able to handle that high . i'm not finding out . i used to use redliine's water wetter . and if it went to 210 i pee'd my pants thinkning the water would boil (red line isn't anitfreeze). im back on usual antifreeze type stuff have been all this (summer) year and i don't see much diffence between last yr with the redline stuff .
it gets hot here and very humid it's 10:pm and the temp is still 78 but the humidity is 78.5 % it sucks for boosting during the day it was in the 90's today .
i was hoping to find out what some other people were getting for known temps or highest seen temps .
supragirl says she flies at about 190 ish all the time thats what the books says too .. ha !

recovery time with the setup is nice and quick , if i do get to boostn and/or the temp starts to climb above 190 for whatever reason it will cool down pretty nice . 190 is it for me . the ride becomes "no fun" higher than 190 . i would love to have someone say they run at 210 all the time so i could chill .
i used a mechcanical temp gauge for a while but i ran the line too close to the exhaust downpipe which whacked the gauge ..
plus the downpipe developed cracks in the accordin flex part which gave me more flase positives . great time for the 3" downpipe and an electric sensor temp gauge .
people will say 160 is too cool and it is but it's not like 160 is hanging around for long . i'll get 160 on a cool morrning or night
the car runs great at 160 or 190 . i drive it everyday in the summer ..cept for rain i rarely bolt on the targa top
. my wife used to have a supra so i'm off the hook a little . the car is a dream to drive and i really wanted to kill the cooling issues so i could enjoy it . i did the same stuff you did i was so disgusted i replaced the engine thinking it had to be a cracked block after a few years of the same crap.
you like that internet address lookup thing huh ? it pisses off a few .. it's a keeper
:D

sorry monkihead i know it's way past your "too much to read quota"

Yeah the internet thing was pretty good!

My biggest problem is on the freeways. It should get some of its best cooling then but that is exactly when the temp starts to rise and keeps going. I have to turn on the heater and get off the freeway and slow it down. I am not spitting out any fluids or anything, but it is unnerving to see it rise. That was why I asked about your new radiator. If it is double row and if you can get the temp to rise then drop back down anytime, then I am going to order one.

I figure that the turbo charging should heat things up just a bit more that the N/A car like mine and a good radiator would hopefully take care of that. So comparing the stock to the new one, did that make all the difference as far as you feeling comfortable when the temp rises, that it would go back down with your new radiator?

Again I appreciate the info.

Later
Russ

crap your's is an N/A ?
i am happy with the radiator
that griffin one you mentioned looks about the same except mounting

mine was a perfect drop in

koyo!