'90 Honda Civic cooling problem, DIY radiator installation questions

OK, here’s the story.

About a month ago, I noticed that my 1990 Honda Civic DX (with automatic transmission and A/C and ~75,000 miles) started getting hot within 5 minutes after starting out. Almost to the red line on the gauge. I was stuck in traffic when I noticed this. I immediately tried to pull off a freeway exit. As soon as I got off the exit, I noticed the temperature drop almost instantly on the gauge from the line below the red to midway on the gauge. But then a couple of minutes later through town, the temp went back up again, only to drop back down later when going back onto the freeway. It did this on the remainder of my freeway trip and ever since then. Doesn’t matter when or where I start out (morning/noon/night, freeway/town), this pattern is consistent. It continues this same pattern: a couple of minutes after starting it would go to almost the red line on the gauge, a couple of minutes later back down to midway on the temp gauge, back up to almost the red line, back down, etc. etc. etc. Never overheated to where steam was pillowing through the hood. As it happened during the Christmas holiday season, I passed it off for fixing until after the holidays, driving it all the while. I would put on the A/C just to keep the fan blowing on the radiator.

I did a little research and concluded (rightly or wrongly) that my thermostat was stuck. So I went to Honda last week to get a thermostat. However, as soon as I was about to replace it, I saw the cooling fins on my radiator were bad. They were disintegrating, crumbling. Whether the thermostat is the root of the problem or not, the radiator will most definitely need to be replaced (I intend to keep the car for at least a couple of years). So I decided that I will go ahead and have the radiator replaced.

My questions to you folk:

Do you think that the radiator is the root of the problem with the symptoms I am having? Initially, I was hesitant to think the radiator was the problem because if the radiator was that bad, wouldn’t it lead to the car always running hot (i.e., not cool and hot like it's running now)?

OK, more importantly, I am thinking that I will attempt to replace the radiator myself and have some questions regarding this. I normally would send the car to Honda, but right now I am trying to pinch pennies as I just bought a new home and have a new child in the family. BTW, I am not a mechanic, but I consider myself fairly handy as I do regular maintenance on the car (tune-ups, oil changes, etc.) and have done slightly more significant repairs to my previous car, a ’83 Honda Civic (water pump replacement, muffler replacement, starter replacement, etc.).

1) Is the work involved too much for a “backyard mechanic”? 2) Do I need any special tools the average “backyard mechanic” would not have access to? 3) How much will a new radiator be (price range)? 4) Should I purchase a Honda radiator? I know that many times buying genuine Honda parts, although more expensive, is always better in the long run. However, I understand that Honda radiators are plastic and am thinking maybe another type of replacement radiator (i.e., metal) would be better in the end. 5) Can I do the job in a day? Will I need more than myself to do it? 6) Any other advice you can give regarding the specifics about radiator replacement in Honda Civics of this vintage. As I understand it, I need to undo all the hoses (coolant, A/C and auto trans.) and fans (I think there’s two?) and brackets to get the old one out. Seems pretty straightforward. And then just reversing what I did. I also plan to put into a new upper and lower radiator hose and a new thermostat at the same time.

Thanks for your time, Chris

Reply to
Seven
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Reply to
Randolph

I have also found that it is also easier to remove the lower radiator hose where it attaches to the engine, and wait till the radiator is on the bench to remove the hose from the bottom of the radiator. bob

Reply to
N.E.Ohio Bob

No, the temp going up and down is not related to speed. It can heat up when I am going down a major hill out of the mountains. That's why I suspect it's the thermostat. Also, fan comes on and stays on when I put the A/C on. Even with the fan running, however, the temp gauge can still head north, just to come down a few minutes later. Again, I am thinking the thermostat is sticking and the coolant can't get back to the radiator to cool. Thus my quest to see if this could be the case from the gurus...

I do want to replace the radiator as well so there are no surprises later...

Reply to
Seven

You should check if your radiator fan and itsswitch are working fine. Never changed a radiator on a Honda but did it on a Ford and a Nissan no problem. It is easier than several other things you have done.I didn't buy new radiators with my old cars. I bought refurbished ones instead. And you should change the thermostat at the same time since you're not sure. You might also want to plus a garden hose into the system and rinse everything clean since you'll be changing the coolant anyway. They sell an adaptor that you can easily install on one of the hoses and plug a garden hose to rinse the system.

Reply to
Paul Bielec

Sorry, forgot to mention I had the timing belt and water pump changed July 2002 at Honda and only put about 12,000 miles on it since then, so I don't feel a need to change the water pump.

Thanks, Chris

Reply to
Seven

message news:...

Chris, I am now wandering what made the fins on the radiator go bad. Do you live in a state that receives lots of snow? If so, I wander if the salt used on the road to melt the snow and ice managed to get on your radiator. Did you drive into some standing water on the road and did the water coat the front of your car? If so, that could explain why your radiator fins are now in bad condition. If that did not happen--it could be a factory defect. You might want to talk to the service manager at the local Honda dealership to determine whether or not there have been in recalls on your vehicle. You may be able to find that sort of information on the internet. Try this site

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Reply to
Tom Wilson

snipped-for-privacy@nospamhotmail.com (Tom Wilson) spake unto the masses in news: snipped-for-privacy@pm3-broad-193.snlo.dialup.fix.net:

This is normal. If you live in an area that gets snow, it's only a matter of time before the fins corrode away. Very common up here.

You have to lose a good chunk of the fins before cooling is noticeably affected, like a third of them. Usually you get a hole in the middle bottom of the rad that goes dusty and falls out. It's that "bottom-feeder" grille that does it.

Reply to
Tegger®

i agree with TeGGeR®, this sounds like a low coolant problem, i had a very similar expierence, i would suggest topping off yuour coolant level and reserve tank before doing anything major.

Reply to
Andrew Smit

Hi,

Yes the coolant was low. Very rusty colored, too. I checked it yesterday before doing anything else. However, I still decided to go and replace the radiator and thermostat. I wanted to replace the radiator now as like I said, the whole front of it was pretty bad, all the fins had disintegrated. And I'd rather not get stuck someplace when it eventually goes bad. I put in a new thermostat as well, being that I was in there, as well as new hoses.

Reply to
Seven

Nope, fans come on. See above.

Ain't that the truth, I got nice and cut up putting the damn thing in!

Took me 12 hours to do it, including chasing down the parts, lunch/dinner breaks, flushing and refilling. Damn tiring. My legs/lower back hurt from stooping over the fenders and front end working in the engine compartment!

I had a Haynes manual, which was just OK. I could have done the work without it, I think. I'd much rather like an official Honda manual, though don't know where to get one.

The damn A/C line hose got in the way of me putting in the driver's side fan. I scratched up the fins a bit getting this fan in with the tight clearances between the exhaust manifold, A/C line hose(s) and the radiator. This shouldn't affect the functionality of the radiator, should it? I also noticed that the A/C line hose is brushed up against the shield on the exhaust manifold. The A/C line hose has a plastic shield around it I am thinking that acts as a shield from the somewhat hot manifold shield. I didn't notice the proximity of the hose to the shield before, so I don't know if this is OK or not. Also, I didn't notice/smell anything burning when I drove the car to work this morning, so I have to assume it's OK. Thoughts on this?

So the car is running cool now, the temp gauge is 1/3, solid. It does not move at all. Awesome! Stop-and-go or straight on the freeway, everything's "cool". The fans are not coming on at all, 'though I don't know if I hooked them up incorrectly or if the engine is not hot enough for them to come on.

Thanks, Chris

Reply to
Seven

sounds like you are all set, to check the fan i think you can unplug both of the wires going to the sullinoid in the rad and connect them together which should turn on the fan, but that may be differant on newer hondas

Andrew

Reply to
Andrew Smit

snipped-for-privacy@aloha.net (Seven) spake unto the masses in news: snipped-for-privacy@posting.google.com:

Yup. When I was there in '85, it rained pretty much every day, usually at night. I was also surprised at the amount of rust on the cars there, until I realized it had to do with the salt sea air.

Reply to
Tegger®

snipped-for-privacy@aloha.net (Seven) spake unto the masses in news: snipped-for-privacy@posting.google.com:

It's been years, so I don't remeber where I saw the rust, Must have been the windward side. We rented a Jeep and went around Oahu a few times sightseeing. I had never before seen such Hollywood-style waves until I saw the windward side of Oahu.

Yes. We stayed in Honolulu like most tourists. Saw lots of older Japanese cars especially, including a jacked-up Toyota pickup with the notation "Hawaii's Own Poi Pounder" in giant letters on the side (that one might have been on the big island...).

Reply to
Tegger®

Thanks!

Hey, George. Don't be so fast to jump to conclusions! I did use cardboard to protect the radiator and the fins and had the radiator protected until I had to remove the cardboard so I could install the fans. I mean, I *do* have to remove the cardboard at some point point, right? ;)

Well, I'm pretty anal about putting things back together how I found them, so I guess the bracket was missing in the first place. I guess I'll have to pull one off of a wreck at the local junkyard.

Thanks, Chris

Reply to
Seven

|I had a Haynes manual, which was just OK. I could have done the work |without it, I think. I'd much rather like an official Honda manual, |though don't know where to get one.

I downloaded a manual (PDF scan) for my 1990 CRX from a website. There were other models available, probably included the Civic. Found the link on one of the CRX tuner sites, so do some Googling. Rex in Fort Worth

Reply to
Rex B

Ah - OK, all is forgiven.:-) I don't recall the '90 Civic layout - mine was sold >5years ago - but in my '92 Integra I was able to remove/install the radiator with the main fan mounted; the A/C fan - the one on the driver side - I dismounted from the radiator before removal and left dangling, still attached to its electrical connections... which I had trouble getting to while the radiator was still in the car anyway.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

Reply to
George Macdonald

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