1990 Voyager overheating problem

Hi:

I've got a 1990 Grand Voyager 3.3 litre automatic that for some time
has been having overheating problems. Basically, if I have to climb up
much of a hill (say going over Roger's Pass in the Canadian Rockies on
a major highway), the engine temp will climb quite quickly and will
sometimes get very close to redline. I think this isn't right - any
other vehicles I've driven can handle such hills without breaking into
a sweat. Also, if it's hot out (ie: summer) and I'm in traffic in a
city, the same thing happens. Is there something about coolant
circulation that these minivans can't handle? Are the rads too small?

For information, I have a brand new, better than original rad, new rad
cap, the fan does come on and I'm not trying to pull anything. I've
also always used distilled water to mix with the antifreeze so there
shouldn't be excessive mineral deposits in the coolant system. Any
thoughts?

Dave

 

This was a known problem that was finally addressed for the 1993 model
year. When the V6 was added for the 1987 line up, the 4 cyl style
radiator was kept. The radiator sat side by side with the A/C
condensor, with each having it's own fan.

When the engine displacement was increased to 3.3 litres in 1990, the
same radiator remained. For most situations, the radiator was adequate.
However, when climbing high mountain passes, it was pushed to it's
limit. I had several aquaintances with pre-1993 vans that had this same
problem. It was always when climbing steep grades. The 2.2 and 2.6 4
cylinder engines seemed okay with this radiator.

For the 1993, a bigger radiator finally replaced the smaller one, and
the condensor was moved in front.

I realize that this does not do anything to address your problem, but
does offer a possible explanation.

-Kirk Matheson

 

I'd also suggest that you consider that the radiator may well have lost a
portion of its cooling capacity due to blockage in both the inner passages
as well as dirt/debris on the cooling fins as well. You can at least get it
to its current peak capability by doing a thorough chemical radiator back
flush and then thoroughly cleaning the exterior fins with a garden hose and
carefully using a nylon brush for any stubborn debris.

Also, as I recall from the 1990 Grand Caravan we owned, there were multiple
radiator options offered. The Heavy Duty version that came with the towing
package had an extra row of coils in the radiator. I know this since I had
to replace our radiator at about 60K miles due to a leaking plastic tank
seam. I saw both radiators at the place where I bought the HD replacement.
If the above suggested actions don't improve the cooling capacity, then you
may have to purchase and install a new HD version.

Good luck.

Bob

 

The radiator, by design, is on the small side. Don't know what kind of
better-than-original unit you've got, but you may need to look into a
very-heavy-duty unit. What is the status of your thermostat?

 

Maybe a 93 radiator, condenser, shroud and fan could
be put in a older minivan?