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A few days ago, The Old Bucket (1988 900S 4-door with original engine, 5-speed trans and clutch) proudly rolled over 250k miles--and its 15-year-old radiator marked the event by p- (no, no, bad word) h-issing coolant from most of its lower third :evil:

Todd Morin, owner of www.eeuroparts.com, offers an OEM rad by Valeo (comes with thermoswitch) for $127, and a Nissens aftermarket unit for $100 (no switch: this is an extra $7). I asked his advice about which to buy, and he told me he sells equal numbers of both! I went with the (Danish-made) Nissens, and ordered the thermoswitch as well.

Here are my notes on changing out the rad:

To remove the old one: Loosen the drain valve (lower RH corner of rad as viewed from inside car); remove cap from expansion bottle; slip 1- to 2-foot length of fuel/heater hose over drain valve; aim hose at suitable container under car (cat-litter pan, say; evict cat first); twist hose to fully open valve and drain coolant.

Remove top hose, and distributor cap (swing out of the way). Remove small hose at rad upper LH corner (this leads to expansion bottle). Unclip airmass meter from air cleaner body; unscrew hose clamp holding its duct to throttle body intake; remove AMM and duct. Pull apart the electrical connectors for both fans. Pull off 2 connectors from thermoswitch.

Loosen the clamp for the lower rad hose. Quickly pull off the hose, then bend it up and back so you can jam it behind the plastic tube through which your battery-to-starter cable goes. This will minimize loss of coolant from block.

Undo the 2 bolts holding top of rad to hood-support crossmember. Tilt rad back, and pull up: the bottom has 2 pegs that locate into holes in rubber bushings in the lower crossmember. Carefully lift rad out (I did this solo, but an assistant really helps here).

Remove the fans. Their screws will probably be very rusty--drill 'em out if you have to. Use a wire wheel in a bench grinder to clean them up, or plan on replacing them with generic sheetmetal screws of the same length. CAUTION: The Nissens rad had holes that were TOO SMALL for the OEM screws! I enlarged them with a taper-reamer. You may want to just buy screws to fit the holes as they come.

Install thermoswitch and reattach fans. Remove metal tubes and rubber bushings from mounting points at top of old rad, and insert in new one. There is no drain fixture on the new rad, just a plastic screw-in plug that you tighten with a flat-blade screwdriver.

Lift rad into engine bay, and guide the bottom pegs into their holes. Watch out that you don't foul the distributor rotor! (Again, a helper is really useful here). Refasten the upper bolts, then reconnect all wires and hoses.

To fill: not as simple as it seems! Turn heater temp. dial to hot; loosen bleed screw (11 mm) on thermostat housing. Cut top off empty 1-gallon windshield-washer bottle just below swage line, and wedge this funnel into opening in expansion bottle (it's a perfect fit). Pour in 50-50 mix of water and antifreeze until it oozes out of bleed screw. Tighten bleed screw.

Start engine. The water pump will suck coolant from expansion bottle; top it up to "full." Wait until temp. rises; you will see 2 or more episodes of bubbling where the thin overflow hose from top of rad enters expansion bottle. After fan comes on and goes off again, top up expansion bottle one last time. Remove funnel, and screw on the bottle's cap. You're done!

Now, go pour some suitable cooling liquid into your own system :cheesy:
 

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Nice job man! :D When I did mine I left the disributor cap on.I bumped it, and completed the job.Then I took it for a test run .It went about 1/4 mile before it missfired and stalled, ruining my new cap and rotor!Glad you had better luck than I!Keep your cool, 8) Pat
 

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its funny you know, around here i have yet to come across a saab with a replaced radiator. you guys must have hard water. this radiators are REALLY FRIGGEN AWSOME! they last decades. my 84' 900sport had the original rad, no issues.

i do want to replace my radiator in my current saab to increase reliability, 17 years and 310,000+ kms i'm sure its going ot go with a bang at some point (knock on wood). i would also liek ot know if the eeuroparts radiator is good, I was thinking of ordering it in the spring and fitting it myself.
 

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I replaced my radiator about 3 weeks ago with the Nissens one and I've noticed a huge difference in traffic with a new rad. Prior to the leak appearing in the radiator 5 minutes in stop-go and the cooling fan was on and off every couple of minutes until I got moving properly (stock 87 thermostat), but after I replaced it it takes about 15 minutes to kick the fan in, and then a lot less often until I get going properly again.

I'd recommend it woywitka if you've got the cash. A new rad will be more efficient which can only be good for the engine, and it really isn't that difficult a job.
 

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I've been running a nissens without rad fan for the last few months, granted the cold weather has helped alot but at worst the temp gauge has it about 2/3rds and that was sitting in traffic moving very slowly for 30 mins, if i'm on a m'way or as long as i'm not stationary in city traffic too much it will stay at 1/2 way and not heat up atall.

When i had the old rad in (the rad fans were'nt working either) if i left the car idling for more than a min it would cause the coolant to boil over.
 

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The old radiator on the car was of substantial construction, with copper fins and brass end-tanks. It had far greater thermal mass than the new lightweight Nissens unit, which has to be better for temperature stability.

Copper is also a more efficient material for a heatsink (which is what the radiator is).

I'm thinking of getting the old radiator re-cored with copper and keeping it as a spare.

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Discussion Starter #8
Matthew said:
ProfZ, I have just fitted a Nissens radiator to my car. What were your impressions of the Nissens unit compared to the OEM lump?
I've been very pleased with both of my Nissens replacement rads:lol:

My 1988 900S was scrapped some months ago with almost 3 years of perfect cooling-system performance after fitting the Nissens rad; my 1990 900S has now also done almost 3 years with the new rad, which still looks and functions like new.

It seems to me that the spaces between the fins are greater than those in the OEM rad core, which would of course improve airflow and heat dissipation. The only (minor) complaint I have is that the 2 Nissens I bought both came without drain fittings (just plugs).

Hope you will be pleased with your Nissens, Matthew!
 

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"Copper is also a more efficient material for a heatsink (which is what the radiator is)." - Aluminium conducts heat better for this application - a heat exchanger not a heat sink. A clean radiator of either material will be more than adaquate and a huge improvement to anything old which has built up a coating of insulating scale on the inside and has narrowing passages.
 

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Saab Mad
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Gloucester Radiator Specialists quoted me £75 +VAT to get the old radiator re-corded in copper. That's for two-layers of fins (I suspect the old one is three-layers but haven't looked closely enough yet to be sure.

I have to say that, with a 82° thermostat the new radiator is performing very well. The car is nice and cool (so cool that I'm thinking of putting in a spare 89° thermostat) and temperature is very stable. Despite the inferior thermal mass, the engine temperature doesn't rise quickly when the car's stationary in traffic.

trackside said:
Aluminium conducts heat better for this application
That's not true - copper is a better conductor of heat than aluminium and therefore more suitable for use as a heat exchanger/sink. Copper has over 50% better heat conductivity than aluminium.

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Dean O said:
sounds a reasonable price, but if this one is a comparable rad then perhaps not?
http://www.carpartsconnexion.com/partdetail.asp?dp=3282
That's a good price - at least £5 less than the cheapest radiator that I saw for sale.

After thinking more about the cost, I'm now not sure whether to get the old radiator re-cored. Seems a waste to scrap it though. It's ever so much heavier than the new unit, and is stuck right at the front of the car, which can't be too good for handling.

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I had a "Nissens" rad fitted about 2 years ago, can't fault it. I also run with a Saab 82deg C stat which is what Saab recommend for a T8 ;)

I had no problems fitting the unit all the holes for the fans were correct

Paul

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Resurrecting an old thread, I found my Saab has a brass/copper radiator. Since that means it can be rebuilt/cleaned, I plan on yanking it out and having that work done (it is like $60 in the local shop). What is currently stopping me is that the hose clamp for the lower radiator hose is clocked such that its business end -- where you put the screwdriver or 7mm socket -- is aimed up towards the bottom of the fan. Let's see if tonight I get that taken care of.

At the same time, I found two 8v N/A 900s in the yard, one 5sp and the other automagic. If their radiators are also brass, would they be drop-in replacements for mine? I just want to have a backup.

FYI, I hate the radiators with plastic end tanks. And I found out they do not like me either...

Also, if you have one of those aluminum radiators with plastic end tanks, consider grounding the aluminum core to the body.
 

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supremedalek said:
Resurrecting an old thread, I found my Saab has a brass/copper radiator. Since that means it can be rebuilt/cleaned, I plan on yanking it out and having that work done (it is like $60 in the local shop). What is currently stopping me is that the hose clamp for the lower radiator hose is clocked such that its business end -- where you put the screwdriver or 7mm socket -- is aimed up towards the bottom of the fan. Let's see if tonight I get that taken care of.
You'll need to remove the fan before you pull the rad out anyway, so might as well just do it first...
 

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supremedalek said:
Also, if you have one of those aluminum radiators with plastic end tanks, consider grounding the aluminum core to the body.
What does grounding the aluminum core do and is it as simple as attaching a wire to the core and to the body?
 
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