Shadyredeyes

Ok so in the past eight months Ive gone through two water pumps. My Temp. gauge doesn't work either for some reason so its difficult for me to monitor the temp. Twice now the engine has gotten so hot it blows the little plug in the top of the water pump. What could cause this? Is my coolant system in need of a good flush or do I have bigger issues?

eseibel67

Your overheating can damage the WP seal. Other possible causes might be contaminated coolant, or a bouncy belt tensioner.

camaronewbie

Are you buying the correct water pump?

I'm assuming you have the serpentine belt system (1988 car), you do know that your waterpump is a reverse rotation pump right? Maybe the part seller is giving you the wrong one. Visually you can't tell the difference between standard rotation and reverse rotation pump.

Also, have you deleted anything like A/C or smog pump? If you have a serp belt system, you can ONLY delete one or the other without using the delete pulleys. There's no physical way to rerun the serp belt and keep the water pump rotating correctly if delete pulley is not used when removing BOTH A/C and smog pump.

Your temp gauge sender is in driver side head, between #1 and #3 spark plug - has a single spade connector on it. The wire is dark green.

Shadyredeyes

Ive been buying reverse flow pumps. I'm gonna replace temp. switch and flush coolant system this weekend to see if that helps any.

87350IROC

iTrader: (2)

Whats brand pumps are you buying. I would not skimp with the water pump.

Also, get your gauge working so you can tell for sure.

Sparkytfl

I'm kind of amazed none of your hoses are blowing up if its getting that hot or pressurized. Radiator cap still good?

IROC4U

fans come on?

drknow90rs_ss@y

iTrader: (3)

Thats crazy! If it is getting that hot, the motor should be toast! Sounds like a pressure buildup thing to me. Check that cap! Maybe buy a "Thermo-cap"?

firehawk1988

I would see what the temp actually is to further find the problem. If you check your sending unit( mentioned above) and still have no gauge, one way to check it is by using a small temp gun. I used one for RC racing to check motor temps. They aren't actually guns but more like the size of a cell phone that you can pick up at R/C hobby stores for around $20. You can point it at your thermostat housing at the top and get temps there to see if the thermostat is stuck or not. You can check hoses, lines, caps, radiator and any part of the engine.

And like said above, don't scimp on a cheap pump. I know on other cars i've seen where they use a cheaper impellers instead of the cast ones. This has caused flow issues in other cars( my brother had this problem in his 3.4 DOHC Monte Carlo)

swisscheese

What pump do you recommend?

Shadygrady

iTrader: (3)

Not the cheapest one you can find.My neighbor bought one from jegs for his RS,Aluminum high flow for around 80 bucks.Not a bad deal if you`re already buying one.

87350IROC

iTrader: (2)

Anything Stewart works well.

87350IROC

iTrader: (2)

I'm confused so you neighbor bought one from Jegs. But which one did YOU get?

Shadyredeyes

I replaced the water pump today and the temp. switch. About to crank it up and see what happens. I'll let yall know.

Shadygrady

iTrader: (3)

Mine is the gm pump that came on my crate engine I bought about 5 years ago.When its time for a new one I will prolly go with the my neighbor bought.

Shadyredeyes

Dont remember what brand the pump was. My fan is coming on. And I replaced the temp. switch today, so now I have my gauge back. I'll keep my eye on it and see if it still wants to act up.

IROC4U

nice id check out a oem 195 thermastat if it does it again maybe it doesnt open

Shadyredeyes

So now my engine will run hot, 220+ unless I turn the heater on. Then it cools back down. But without the heater on it gets hot again. I didn't see my fan come on yet during this either. My top radiator hose builds up pressure also. Is my thermostat stuck maybe? Is it possible my fan is shot? Really need this fixed due to being a daily driver, and a naggin old lady!!

Shadyredeyes

I just ordered a fail safe 195 degree thermostat to replace the one in my car. Not sure if it's bad but it's a start I suppose.. Also I will soon replace the radiator cap. The one I have is at least three years old, although it looks ok to me. I'd rather have one that I can bleed the pressure off of.

Shadygrady

iTrader: (3)

If your fans not coming on at about 195 its either shot,the fuse is blown,relays bad or something to that effect.Thats where Id spend my time checking before buying anymore parts.You could try to hook it directly to a 12volt source to see if it comes on.
There is a tech article off the main page called total fan control that should prove very helpful.

Gumby

180 is the sweet spot

http://www.carnut.com/ramblin/_cool3.html

Shadyredeyes

I noticed today my fan comes on when I turn the heater on, but not for long. I plan on hard wiring it tomorrow to see what happens.

Shadyredeyes

How do I wire my fan to a 12V supply? sounds dumb, I know but I tried to just put wires from my battery to where the fan plug is and got nothing in return. Is there an easier way to do it?

Shadygrady

iTrader: (3)

You can wire the power to an acc. in the fuse box,then find a good ground.IMO i would try to hook it up factory.There is a how to in the tech articles

https://www.thirdgen.org/electric_co...pec_mod_single


https://www.thirdgen.org/electric_co..._spec_mod_dual

Or here.In the stickies on top of page.
https://www.thirdgen.org/forums/cool...total-fan.html

Gumby

If you wire any fan direct, make sure you turn it off before the car or the spinning down of the fan motor, will keep the juice flowing and the car will run for a sec after shutting off the key.

Not a big deal just note that, I can do it in my Buick but I got the fan blower wired direct because a full 12volts sent to it MOVES air. 3-4 setting beyond the typical GM high.

Shadyredeyes

Ok so now my fan will not come on with the temp at 220+. But it does come on if i turn my ac or vents on. Which leads me to believe the fan motor is still god. Should I replace the relay now? Got a new thermostat coming Monday. I've already flushed the cooling system. What now??

Gumby

you may be cursed, get yourself some bells and hang them in random places under hood and car, gremlins don't like the ringing of a bell.

They also work best when given to you / don't go out and buy them yourself.
Xmas stuff is agood place to look.

but you can try the relay, fan should come on with AC as it would then run hotter.

Though I don't member what stock temp is, I know my V6 it didn't come on till well over 200 factory. [now it never goes above 200.]

Sparkytfl

I think its more likely the temp switch than the relay.

Shadyredeyes

I've replaced the switch already though.

bluegrassz

iTrader: (3)

What about the fan switch in the passenger side head? Its between #6 & #8 cylinder. You can remove the connection and ground the wire. When the key is on, then the fan should run with the wire grounded.

cuisinartvette

Wonder what the switch is rated at? There are different temp ones you can get that will have it come on sooner

Shadyredeyes

Replaced fan switch as well bluegrassz. Still does this. The temp switch was rated at whatever the OEM replacement is set at cuisinartvette. I'm not real sure what that is, to be honest with you. Maybe I should just replace the switch again. It's been a while since I changed it.

bluegrassz

iTrader: (3)

Did you try grounding the connector on the fan switch?

henryd3

iTrader: (128)

I've had many of those fan switches only last a couple of months. If the fan comes on when you turn on the AC then your fan and relay are fine. You need to take the connector off the fan switch and with the key on ground the wire to the switch. If the fan comes on the problem is that switch

Shadyredeyes

I'm about to go try to ground the fan switch and see what happens. With the switch grounded the fan comes on. Guess I know what I'm buying tomorrow. Thanks alot Blugrassz. One of two problems solved now.

Shadyredeyes

My plastic pigtail connector crumbled away while checking the fan switch. Where's a good place to get another one?

Shadyredeyes

Changed my cooling fan switch today, still have the same problem. Guess my fan relay is the problem now. I'm about tired of changing parts and getting no results.

Awesome-X

You may as well just wire the fans up to a switch. Or buy a programmable one from Ebay.

And I saw in there somewhere that you said you wired your fans to your battery and nothing happened...they should have come one immediately and ran until you severed the connection.

Shadyredeyes

When I wired the fan to the battery I dont think I had a good connection. I talked to a guy today who was a GM tech. in the 80's when theses cars were new. He said it sounds like my passenger side head might be cracked or have a bad head gasket. Said it was common for the 305 to have higher temps in that side due to smaller exhaust ports. Hopefully thats not the case.

Shadyredeyes

Any suggestions on a good programmable switch? I'm looking at a Derale 150 to 240 degree switch. I also found one with a 1 amp inline fuse to protect the relay. This one cost $50 more. Is it really that advantageous?

Elthesh

Alright, hang on a sec. Did you properly replace the crumbled pigtail along with the passenger side temp switch? I replaced my pigtail last year as it fell apart and was just hanging there. Works fine now. If so, are you test it at the plug end to see if it turns on when you ground it? If it works then and you replaced the switch, then unless the switch itself is defective, it honestly HAS to work. The switch turns on the fan when the car gets to about 220-230. I forget the exact figure. Might even be 235.

You really need to get a completely accurate temperature reading and not go solely on the dash gauge. Also, the car WILL run at 220 degrees on the gauge. That is dead normal. Once it goes above that, a bit, then the secondary fan turns on. The only time the car runs cooler than 220 is on the freeway or in freezing weather. Mine runs at a completely steady 220 degrees in the Florida heat. It has since I bought it 8 years ago. My first 91 back in 93 also ran at 220 degrees when heated up.

If you are blowing water pumps at 220 degrees, then you have another problem that needs to be addressed.

Have you replaced the radiator cap? Get an AC Delco one, the factory original. On my 91, it is an RC27. Likely the same for you, but check.

Have you had the system pressure tested and completely professionally flushed? Get all that done first because hardwiring the fan when you very likely have another problem is a bad idea.

Again, my secondary fan, the one that also turns on when I turn the ac on, does NOT turn on itself until the car is over 220 degrees. Could be 225 or 230. Somewhere around there. My car also has almost 200,000 miles on it.

90 camaro cj

ummm i just came across this page but idk what everyone is saying... the stock fan comes on at about 225 and turns back off at 200ish sitting it traffic my car will get hot hit about 225 to 230 on the gauge, fan comes on and cools back down. idk y everyone is saying that thats high...

Shadyredeyes

My engine will skyrocket into the red on my temp gauge. Sometimes it will come back down to around 220. Most times it won't. I have not replaced the radiator cap yet. Will do that today. I also have yet to have it flushed out. I personally haven't driven it in about a month, but my ex girlfriend did. I'll drive it around and see what its actually doing this weekend. When I let it run in the driveway it shoots up into the red and my fan, single stage factory one, never comes on unless I turn the ac on full blast. Then the engine cools down to around 220.