teamtoken

Hi folks

Im having heating problems with my 98 civic hatch. A few nights ago I was stuck in crawling stop start traffic, where after about 15 minutes I noticed the temp guage slowing starting to climb beyond the half way point. It got pretty close to the top of the guage, before the traffic cleared to normal highway speed and I got back up to 80km/h (or 50mph - im in australia) it quickly settled back to normal temps. I wasn't overly worried, excess heat is to be expected in such conditions

I replicated the same stop start conditions in the street outside my house and it start doing the same thing after only 5 minutes, took it around the block and once up to cruising speed the temps settled back down to normal. Radiator fan didn't seem to come on. Fluids are all ok. Temp is fine when left stationary in idle. Car is completely stock

Not sure whats going on here, but any help would be greatly appreciated!

Thanks

NotARaCist

iTrader: (1)

Open your hood, start the car, and let it sit and warm up. Watch the radiator fan. Does it come on?

teamtoken

Radiator fan does not come on, AC fan comes on when A/C is switched on, nothing from radiator fan though

NotARaCist

iTrader: (1)

Disconnect the radiator fan switch (it's the one screwed into your thermostat housing) and use something to connect those two prongs on the plug (not the switch, the plug), with the key turned to ON(II). Does the fan turn on now?

teamtoken

Just tried that, but with a paper clip, fan works.

So fan works and relay works so it must be either the fan switch or thermostat I presume? I think ill order both parts and replace the two of them. Im hoping its not something more sinister!

While im at it I may as well do a coolant flush as well. I only just picked this car up a few weeks ago so I don't know how old the coolant is. Is there any problem with using different types of coolants? Pretty not sure this is not the genuine honda coolant in there, which ill be replacing it with.

Thanks

NotARaCist

iTrader: (1)

Standard coolant is standard coolant. As long as the last person to flush didn't use some "do not mix with" stuff, you should be fine. Diagnostically, the test points towards a bad switch. Since it's all in the same area, it doesn't hurt to replace the thermostat too, just make sure you replace both with OEM.

teamtoken

Thanks notaracist

Bad update. Was just driving before for around 30 minutes, pretty calm driving, No stop start, temps initially good, its a hot day here, 35 degrees and humid as hell. Pulling into my destination and start seeing steam coming from the bonnet, temp guage is maxed. Quickly pull in and shut off, its dropped a lot of coolant, radiator looks empty. Now stuck at the gym wondering what to do. Might try the paperclip trick in the fan switch plug and try and limp it home. As its an aluminium engine im pretty worried thats it overheated so badly as it aluminium warps. The thermostat and fan switch can't come soon enough, although im wondering if its something more serious?

NotARaCist

iTrader: (1)

If you went steam status, it's extremely likely that you blew the head gasket.

teamtoken

Ouch

Ive just attempted to drive it home, filled with full coolant, radiator fan on, now overheating within 15 minutes. Had to leave it by the side of the road.

No smoke, but spat more coolant. Is a head gasket the most likely? Its been running like an absolute charm until 3 days ago. Unbelievable.

Jimi Hondrix

Could be a:
1) Crack in bottom of radiator
2) Leaking radiator or heater hose
3) Thermostat
4) Head gasket breech

These piece of **** Hondas can't take any overheating without blowing a head gasket so, that's most likely the issue. These Hondas have blown more heads than a 50 year old **** *****. Goddamn pieces of Shivics..lol

teamtoken

Thanks Hondrix

Drove the car today from where it has been sitting on the side of the road. Started up, running well, no smoke at all. Driving around the back streets for a little to see what it did, fine for first 5 minutes, then temp gauge slowly started rising above half way. Quickly pulled over and shut off. Seems like theres no coolant at all circulating through the motor? Getting a roadside mechanic to come out and look at it tommorow, then to get it towed back to my house.

By some divine miracle its looks like the head gasket could be ok. No smoke at all, oil was fine, coolant looks good, car runs smooth.

Jimi Hondrix

One thing I left off the previous list: Waterpump.
Is there a leak near the waterpump?

Being that it's overheating so quickly it seems like it's likely to be thermostat or waterpump. However, even if it is either one of those, there's still a possibility of a blown head gasket due to the engine overheating. White smoke and coolant mixed in oil aren't a common failed head gasket sign with Civics. Read this: https://honda-tech.com/honda-civic-d...g-why-3265707/

existanzcivicb20

at this point i would start with the cheapest easiest thing and that would be replace thermostat. start the car, add coolant, leave the radiator cap off, turn heater on full blast, keep adding coolant as the thermostat opens up.

NotARaCist

iTrader: (1)

Or we can stop beating around the bush pointlessly. Do a block test.

existanzcivicb20

What do you mean by block test? Compression test?

NotARaCist

iTrader: (1)

No, I mean a block test.



Suck up a small bit of coolant, apply litmus, if litmus changes, you have exhaust gasses in your coolant, which definitively means you have a blown head gasket.

existanzcivicb20

Wells thats pretty handy!!!

nixrox

OR you could just do a compression test.

By the way - I am a journeyman mechanic with 50 years of experience and I never, ever use anything OEM from the manufacturer, unless I cannot find it anywhere else. 99 percent of what the OEM's sell is overpriced crap made in China. So I just buy everything from China direct through a local retailer and it saves me and my customers a lot of money.

I also buy my oil in bulk containers for the cheapest price possible and change it every 10,000k along with the filter. I always use 10W30 or 20W50 oil in my Hondas because they are high reving and need the extra viscosity. Aircraft engines use 100 weight oil so it makes sense to me.
I can not even estimate how many main conecting rod sets of bearings I have replaced for people who were using the OEM specified 5W30 oil in the cars.

Enough of my rant about OEM.

NotARaCist

iTrader: (1)

Compression test is not definitive. Block test is. With your "50 years of experience", you should know this.

nixrox

Your joking right????

How many years of experience do you have as a licensed Journeyman Mechanic who specializes on Honda cars?

NotARaCist

iTrader: (1)

No, I'm not joking. Throw whatever credentials around all you want, but considering that you don't know the differences in diagnostic uses of a compression test vs. a block test, I'm gonna go ahead and say...



It's unfortunate that you make it so easy to tell that you're lying, though. If you'd like, I can also point out that you're making a pretty blatant logical fallacy called "appeal to authority". What you're saying should be able to hold it's own water without the nonsense of who you are. Unfortunately for you, it doesn't.

tony_2018

Compression test won't tell you if you have a blown gasket, a sure way is the block tester. If exhaust gas is introduced in the coolant the tester will change colors.

Compression test can only tell you that you're not holding compression properly, that could mean either rings or a bent valve, etc..etc..

nixrox

Wow you guys are really living in a dream world.
If this is the kind of definitive knowledge you spout on this web site then I'm outa here.
Have fun in lala land.

NotARaCist

iTrader: (1)

No loss.

Jimi Hondrix

Best test is leakdown but that can be expensive to either buy the equipment needed or have it done at a shop. For $10 of test fluid and free rental a block test is the next best and lowest cost option.