new owner 1990 zr1
 

Hi having cooling problem!! temp almost pinned 2/3 and fans are working but radiator is a mess.started pulling shroud out and going to continue today,somebody mentioned the (high press by pass valve) is this a concern and where is it.thanks for any help!!!

Re: new owner 1990 zr1
 

try first pulling the radiator out and cleaning out all the cooling fins .our cars are hoovers picking up all sorts of things . that should solve your cooling issues.. you might also get on mark haibecks site for other cooling solutions .sorry don't know how to do the link thingy

Re: new owner 1990 zr1
 

if your rad is blocked that's going to hurt your temps, clean that and get an aftermarket chip. I suggest mark haibeck at www.zr1specialist.com. as for the by pass valve, over 5800 rpm the rad can't handle the flow of coolant so it bypasses the rad and goes back into the block causing temp to go up. Found this out the hard way, I was playing around in second gear one day, looked down and almost **** my pants. If you swap the rad for an aftermarket one you can get rid of this "feature"

Re: new owner 1990 zr1
 

Thanks guys started shroud and met up with the three on drivers side and realized my small ratched was not in tool box,thanks again cant wait to see this radiator.

Re: new owner 1990 zr1
 

Here is a link to Marc's website section on a clogged radiator. I had this problem on my 93 and had to remove it and hose it out. ---Bob
http://www.zr1specialist.com/HAT%20W...o/radiator.htm

Re: new owner 1990 zr1
 

BTW, at high revs, you don't stop flow through the radiator, you just run excess flow around it.

Re: new owner 1990 zr1
 

Thanks cant wait to get home.

Re: new owner 1990 zr1
 

HELP !!!!!! SHROUD LOOSE WHATS THE TRICK FOR GETTING IT OUT?

Re: new owner 1990 zr1
 

I had the same issue. Took it to Marc's for some other work and had him pull and clean radiator. It was nasty - even with 18k miles on the car. 1/3 of it was covered in oil from oil cooler lines that had leaked at one time - which attracted all kinds of dust, vegetation, and fuzzy junk. The rest wasn't as bad - but it still had a lot o junk in it. He used like 2 cans of brake clean just to get the oil out (so you know what to expect). If your car doesn't have a debris screen on it you can make one pretty easy. http://www.zr1.net/forum/showthread.php?t=20178
I also went with Marc's chip - and between the cleaning and the chip I went from running 200 on the road and 230+ in traffic - to about 180 on the road and 210 in traffic...

The shroud takes some wiggling to get off there - I didn't do it but I watched Marc and it takes some careful wiggling and lifting...

Re: new owner 1990 zr1
 

Ill get it just looking for some tips haha!!thanks

Re: new owner 1990 zr1
 

ITS OUT AND REALLY DIRTY, ANYONE KNOW IS THE WATERPUMP SOMETHING I SHOULD DO WHILE IM IN THIS MESS.

Re: new owner 1990 zr1
 

only if it's leaking.

Re: new owner 1990 zr1
 

Welcome onto the boards there...

Re: new owner 1990 zr1
 

Keep cleaning until you can see some good light from behind or better yet, get a new & or alum rad, why put a old rad back in, just asking for another rad pull soon

Re: new owner 1990 zr1
 

I was thinking same thing,sometime I go over board and replace things that don't need it, rad is in great shape though ,but gonna go new along with the hose kit from marc and possible wpump.

Re: new owner 1990 zr1
 

if you do the water pump be very carefull. as the bolts MUST go back into the hole they came out of.

Re: new owner 1990 zr1
 

Hi trying to find out info on this procedere, have you done one and how difficult is it?

Water Pump Installation
 

I use a very thin coat of Permatex 300 Form A Gasket on each side of the Water Pump gasket and IH coolant manifold gaskets (unless you have eliminated TB coolant) before installing. I use a drop of Blue Loctite 242 on all water pump bolts and torque all water pump bolts 18 ft-lbs. NO LEAKS

http://i287.photobucket.com/albums/l...a6c00b8a76.jpg

http://i287.photobucket.com/albums/l...psaf26fa81.jpghttp://i287.photobucket.com/albums/l...%20ZR1/242.jpg

Now if you get confused on which bolts go where......just insert the bolt and if it sticks out about 3/8 inch to 1/2 inch you have the correct position for that bolt :p

Re: Water Pump Installation
 

Didn't someone just post in another thread that the bolt sizes noted in the FSM are indicated incorrectly? --Bob

Re: new owner 1990 zr1
 

Did you pickup a new radiator?

Re: Water Pump Installation
 

I just pulled my water pump a couple days ago using this diagram, and all the bolts were a perfect match. Made my own drawing to put the bolts on so I know they matched. Will also make it easy to install the new pump.

Re: new owner 1990 zr1
 

YES I GOT A NEW RAD,WPUMP ,HOSES,AND THERMOSTAT.

Re: new owner 1990 zr1
 

Be careful of your thermostat, there were some bad ones out there.
http://www.zr1specialist.com/HAT%20W...thermostat.htm

Re: new owner 1990 zr1
 

Got a stat from napa, does the tensioner need to come out and there is a bracket under the altenator does that come out.ALMOST THERE

Re: new owner 1990 zr1
 

Pulling the tensioner is like a 5-minute job and makes everything else easier to get to. Stand on the passenger side, grab the tensioner and pull towards you. The belt will just about fall off. Then unbolt the tensioner and remove. Enjoy the increased access. :)