87 Prelude starting to get warmer

Hi there,

Just wanted to confirm my diagnosis, the temp in my girlfriends
87 prelude (carb) always sits around half, then when you let it
sit, it goes over half.

The upper rad hose is frickin hot, and the lower is not so hot.

So I was thinking 1. thermostat, 2. coolant replacement, 3. Water pump
as the order for repair.

Also, just wondering if the rad could be a huge prob, and what
would be the best alternative for rad replacement if necessary.

I am located in Winnipeg, Canada.

THanks!

t

 

++++++++++

If anybody has used Winnipeg tap water to dilute the coolant in the
past, that could explain why the rad would be corroded.

You didn't mention how often the cooling fan(s) are running. Water pump
runs all the time, so, unless the impellers are corroded OFF the pump,
it's not a likely suspect. It should still be replaced as part of the
timing belt schedule.

'Curly'

 

Thanks Curly,

Hey whats wrong with winnipeg tap water??

It doesn't look like the water pump is part of the timing belt
system, the pump runs off of the alternator belt, so it should
be an easy check to see if the impellers and bushing are in good
shape...

I will have to check the fan, i'm pretty sure its workin though

t

 

------------------

Ooops, you're right about the water pump being different. With a vehicle
that age, crudded rad is a good possibility. 'Curly'
---------------

.....

 

Alright, so i went in and changed the thermostat to a 180F, even though
the OEM replacement is 192, since i figure the cooling system can use all
the help it can get.

First off, good idea?

Second, when i drained the coolant, it was BBBB-LACK. It didn't foam up
much
when i poured into the jug i used to store it til i take it to
the recycler, but i thought it was odd that it was that dirty.

I ran a garden hose thru the system once it drained, so i think i got all
the loose crud outta the system, or do i have
bigger problems?

I can't see any oil beading up on the top of the fluid (or the bottom, I
can't remember what is heavier, though i assume that water with coolant in
it is)

thanks
t

 

Probably not. If your engine is getting too hot, you either have
improper temperature regulation (bad thermostat, failed thermo switches
etc.) or you have insufficient cooling capacity (clogged radiator,
blocked hoses, too many insects blocking airflow through radiator etc.).

If the problem is insufficient cooling capacity, a lower temp thermostat
isn't going to help. If the system can't maintain 192°F it certainly
won't maintain 180°F.

If the problem is improper temperature regulation, the thermostat
certainly is a likely failure point, so replacing it is a good, cheap,
idea. There really is no point in not using the specified temperature.

If the engine is running too cool, you can get into issues where the ECU
never gets out of the cold enrichment mode etc.