[mike nixon]

You need to run some flush thru that thing, It's filthy inside and that's probably the source of your overheating. The fallout from that may end up being a plugged radiator and heater core [if it was ever hooked up with this].


Mike

[screamingchief]

Lot of stuff going on here,eh Clay.

Where to start,OK the flushing,as some have mentioned you might try pulling the block drain plugs out if you can get them out (hit or miss proposition often),in the past that has been one of my favored methods of clearing crap outta the cooling system,though as with other methods,it may take some multiple tries to get the desired results.

Otherwise a cooling system flushing kit like somebody mentioned earlier that does a reverse flush would be the next best option,or if you understand how that's done you could adapt what's on there now to do the same thing seeing as you dont have the heater core hooked up.

The advice on pulley ratios is sound advice,so keep working on that front.

In the pics,the exhaust looks like your planning a turbo install down the road?

Is that exhaust on there now???

If those turbo logs are too restrictive,that could aggravate any potential cooling system issues,the engine needs to get those hot exhaust gasses moving to keep the hot manifolds from radiating their heat load back into the cooling system,make sure the logs dont actually touch the block anywhere if possible too,as that would be a very bad situation to have (direct contact transmits heat very well).

Might try some other exhaust set-up if you have something handy,but I know that's probably a stretch here.

And you need to be 100% sure the radiator is mounted high enough,I see you converted from a downflow to the crossflow,and that's a move I approve of,providing the proper care is taken to ensure the new radiator location is correct,and the cap remains the highest point in the system (that is not optional,not unless you take very specific measures to address such).

None of the pics give a very good angle to judge that situation,so honestly I cant tell much from those pics in that respect.

Also somebody mentioned adding a coolant recovery jug,that's another very good idea seeing as you switched to the crossflow rad,this would be very easy to do once you know for sure the radiator cap is at the highest point in the cooling system.

And as mentioned,the current radiator shrouding situation leaves much to be desired,so keep working on that too,the better you seal that shrouding to the rad,the more air that moves across the rad core and the better the cooling system should work.

This "shrouding" deal in and of it's own right could fill a book,but understand the basics and that knowledge can take all that theory pretty far in practical terms.

Rarely ever is one issue alone responsible for these hard to fix cooling situations,often it's a series of smaller issues together that make for a bigger problem.

I'd also suggest you lose the universal "ribbed" radiator hoses,they are a step backwards IMHO,if the custom molded hoses did'nt have the "anti-collapsing" springs in them (mainly just the lower hose needs one,the upper hose does'nt really need that),then you can buy that spring seperately and add that to the molded hoses.

I'll just end this by saying that I feel there absolutely is a resolution to your cooling system problems,but it wont necessarily be easy or fun,just work your way thru the detail items,and do not get too far ahead of yourself trying to solve this deal,try to avoid making multiple changes at one time,as it's nearly impossible to determine what net result any one change has at that point,take your time,stick to the "basics" of cooling system dynamics,and try to be patient if you can.

Feel free to PM me Clay,I'll be glad to help with any specifics that I can.

HTH

BP.

[baron_]

Thanks for the replies.

I'm on flush #21 or so. And its still really really dirty.
I can drive it around for about 20 minutes without it overheating now (give or take)
And then I come home and pop the hoses and its just as dirty as ever.

I flush until everything is clear (3 or 4 minutes)
Flush radiator out first, then flush block out by hooking up bottom hose and leaving top off - its still surprisingly nasty

I read BP's thread about having the radiator cap highest - done that

I figure I'll just keep flushing until its all clear (i think its getting marginally better - its not frothy dirty anymore, just reddish looking)
And once I'm sure that isn't the problem, I'll move to the next thing =]


And yea....turbos were the plan
This overheating issue is a rather large thorn in my side, on that project.
Delayed things rather impressively

[mike nixon]

Clay, I'd go to NAPA or Carquest and buy a bottle of zerex flush. Dump it in the radiator and drive it a day or so if it'll stay cool then flush it and see if that breaks most of it loose.


Mike

[baron_]

I tried Zerex a few days ago. With how much i'm flushing....and how much is coming out from simply running the car for 15 minutes, then draining....i'll wait until its clearer to try it


Here's flush #24. This is ridiculous.


I think its a bit odd.

Drive for fifteen minutes (or 10, something like that). I try to get it up to about 210 degrees
Take bottom hose off - drain radiator...looks like picture below


Then put on bottom hose and unplug top hose....and fill again, so that it comes out the block and top of radiator
And it'll empty some more nasty stuff
3 minutes with a hose later, everything is crystal clear.
Fill with water....

Drive 10 or so more minutes and get up to temperature, and its just as dirty again.
Is that unusual?
I figure the pressurized system is stirring stuff up that simply flushing can't get?

[chiphead]

Lots of rust and gunk from a poorly maintained cooling system. I've had this happen and it's a nightmare. I was never able to clean the water jackets and had to pull the engine. Too much scale in the bottom of the jackets to flush clean. As I said, your radiator is now totally contaminated and stuff is coming out of it as well. The rad tubes act as a filter and will just collect rust and scale until it compacts in the tubes and blocks the radiator off internally.

As a sanity check, I would do all normal tests of the headgaskets. Leakdown, compression test, pressure test cooling system, etc.

[baron_]

...as long as this isn't extraordinarily weird or something


I have no problem flushing 100 times, adding in some evaporust, etc etc
It gives me hope that it's all there is to the overheating problem

[lust4speed]

A tablespoon of Tide in the water on each refill will help also clean out some of the gunk. The soaps for washing machines are very low sudsing, and this is what you need in the cooling system. You can afford to do this multiple times, whereas the profession flushes are expensive which limit you to a one time shot. I'd go the cheap soap for a number of flushes and then finish up with the commercial stuff left in for several days of driving like Mike says.

[baron_]

I'll start with that as well
I've got a gallon of evaporust in there right now.
gonna play with that for a day

[baron_]

Also, was thinking about BP's comments


Might i be overheating the entire engine compartment with those turbo manifolds merely dumping in the middle of everything?


the temp very slowly crawls up...
I guess it gets to 150 reasonably quick
But then takes a few minutes to get to 180, and a further few minutes to get to 210

Maybe I'm overheating the radiator, engine and everything else after about 10 minutes?

I may try a different exhaust....to route it out of the engine bay

[baron_]

Rerouted the exhaust. Quite nice....no more fumes in face.

However, still overheated....

Evaporust drained this morning was almost black looking, it was so dirty.
I'm on flush #25, #26 and 27 today. Still rusty looking...but might be some progress.

Running out of ideas, short of a big fan shroud (which I shouldn't need)

I may try raising the radiator an inch. Its above the outlet, but not by terribly much

[GTOJOE228]

PLEASE REFER TO THE THREAD "The Magic Bullet"...Drum roll please! Under Heating and Cooling....

[baron_]

I refuse to pay that $$$ for a pulley like that, thats ridiculous

Maybe it works, but its just masking a problem in your cooling system that you should discover, first.
(my two cents)

I'll find this problem eventually.


On the other hand, its nice to be driving your ride. Congrats!

[GTOJOE228]

Originally Posted by baron_

I refuse to pay that $$$ for a pulley like that, thats ridiculous

Maybe it works, but its just masking a problem in your cooling system that you should discover, first.
(my two cents)

I'll find the problem eventually.


On the other hand, its nice to be driving your ride. Congrats!

Hey Clay,

I've done all I could in combating this elusive problem. Mind you, my car never overheats...it just runs hotter than I'd like. This solution, although masks the problem, gives me a temporary fix until I nail it for good.

It does feel good driving instead of guage watching......Good luck with yours....

GTO JOE

[ctgross]

Not to take away from the baron's ongoing problem....I'll offer my latest on the battle of heat. For the past two years I've been running a 160 deg. stat. with 3/16 holes drilled around it. When I first did this, it seemed to drop my temps about 10 deg.(from 220 to 210 at full warm-up on a 95+ deg. day). About six months ago I learned my fan clutch was worn...replaced with standard duty Hayden...temps. seemed to drop on average about 10 deg......BUT, this was on days of ambient temps. in the 50-60's. Last month I drained, flushed and filled with a 60/40 mix of coolant/water. When I did the flush, I changed my thermostat to a Mr. Gasket 180 deg.

I had my first chance last Sat. to give it a good testing on a 220 mile round trip ride to a car show. When I left home it was 75 deg. and the car never got over 180 deg....average seemed to be 160-170. On the trip home, the outside temp. was 90 deg. with high humidity...the temps. of the car were exactly the same, even when I ran the a/c for about 15 minutes just to see if it would make a big difference.
I am firmly convinced that finding the correct thermostat that permits the water to stay in the radiator long enough to cool is a huge factor in this battle.

The past couple of years I had just about resigned myself to believe that no matter what I did to the cooling system...it was going to run 110 deg. above ambient temp.

I've changed my thinking on that now Guess the summer months ahead will give a good test. Right now I'm super pleased. Sorry for the rant, and not to step on your thread baron

[baron_]

no problem

I haven't had a car yet where the thermostat ever made a difference - a real difference
I don't know if i buy the whole theory about keeping water in the radiator longer....giving it more time to cool

My thoughts........
Suppose water pumped 10 gph goes through the radiator and system in one full minute
If we go up to 20 gph, it will go through the system twice in a minute (roughly)

Yea, the water in the 10 gph example will have twice as long in the radiator to cool the first time its in there (and only time)
But the water in the second system will be through the system twice...exposed to just as much as the radiator in terms of time...just half as long each time


Seems like slow, or fast...they're the same


You changed the clutch fan which was worn, and the thermostat
I bet it was the clutch fan and not the thermostat that made the difference

[george kujanski]

Slower flow is a myth. Slow it down to zero, if it's true, that would be the optimum. More flow is the key.

Don't take my word for it; Visit any heat exchanger mfgr's website and view the performance specs of their units. They will all show that greater flow for both air thru the exchanger and liquid inside provide greater heat transfer. Real data, not opinions.

George

[lust4speed]

And more flow has a better chance of supplying enough coolant to the nooks and crannies where steam pockets like to form. Slow down the water path and you decrease the ability to properly purge these hot areas.

[baron_]

Good news: I drove it for about 2 hours today...90 degree heat
Didn't overheat! Didn't even hit 180, which is what I wanted. About time!


The culprit? Daggone lower pulley was still slipping, even after changing from the march billet pulley to a nice stocker. Evidently, the stocker was still too slippery

I put on the rustiest lower pulley I had and bingo - no overheating.
Only took....2 weeks to figure out.

Unfortunately...now that the belt isn't slipping, its squeeling like hell.
Comes in at about 2,000 RPM

I'm pretty sure its because I don't have a power steering belt on this car. Later style pulleys and 11 bolt setup with a single belt (alternator)
I'm running manual steering.

I've read and heard that you should have two belts turning the water pump or they'll slip and squeel (too much for a single belt to turn all that without slipping)


Anyone have a solution to that?
I'm hitting napa tomorrow and see if i can get a super tight belt i can put on the pulleys and get lucky...it fitting perfectly (good luck)

[bnorris_74]

See if you can measure close enough to get a belt to run from the fan pulley straight to the crank pulley. there won't be any adjustment and you'll have fun getting it on. Just don't get too tight or you'll trash your water pump.