bigtunadaboss

So my radiator fan isn't switching on. So far I've put a mishimoto radiator, mishimoto fan and hoses for the cooling fan upgrades. Now I've also replaced the thermostat with OEM one, I've replaced the ECT and the Radiator Fan switch also with OEM ones. I've put working relays in. And If i run a paper clip to the radiator fan switch and jump the connectors the fan comes on. I've tried 2 new switch and neither of them have fixed it. I can't verify the engine is overheating but the top hose is indeed hot and the overflow tank starts to fill up. What are other things to check?

This issue was happening before I put the upgrades on and it just appeared out of the blue since the fan was originally working a few weeks ago and I haven't driven it since.

Wankenstein

In the meantime, if not already doing, leave the fan jumpered whenever driving so the fan stays on. To test coolant temp...drive it operating temp for 15 minutes then slowly open the rad cap with a rag, stand back while doing so, open the cap halfway and let pressure release. After a minute or two remove the cap and test coolant with a high temp thermometer.

Coolant overflow in reservoir could be due to a blown head gasket.

bigtunadaboss

I've been taught if you rev the motor with the radiator cap off you should see bubbles for a blown headgasket. I don't see any when i do this and doesn't the overflow fill when overheating.

Wankenstein

There's several types of head gasket breaches. Best test is a leakdown test on each cylinder: 150 psi of compressed air injected via spark plugs holes at TDC with radiator cap off and look for bubbles. I prefer to start with a block test because it's cheap and easy (free rental at auto parts store). However, it doesn't detect every type of breach but if the blue test fluid turns yellow or green it proves exhaust emissions/leak and if the fluid stays blue it will then need a leakdown test (more time consuming).

IMO revving the engine to find a possible head gasket leak could lead to a false-positive as air bubbles are created by water-pump cavitation at high revs. With honda 1.6 and 1.7L engines the strongest symptom of a headgasket breach is a decrease in radiator coolant level and in increase or overflow of the coolant level in the reservoir.

bigtunadaboss

regardless assuming I have a blown headkgasket which is possible I’d still need to figure out why the fan isn’t coming on our else I’d just blow another head gasket right away.

Wankenstein

If you can't figure out how to get it to work then just keep it jumpered so it's on all ther time. Doing so will slow the time from cold start to operating temp and possibly cause the rad fan to wear out quicker ( should still last years) but other than that it shouldn't cause any harm. The previous owner of my car said he jumpered it for years but I removed the jumper soon after purchasing it three years ago.

Has the temp gauge on the dash ever went higher than half way (cold to hot)?

bigtunadaboss

yes so I’m already assuming headgasket is blown.
It’s never hit the red but it’s been about 80% of the way there so.

Wankenstein

Do a block test on it and/or if you have a 150 psi air compressor do a leakdown test. Also, jumper the fan and run the engine with the rad cap off...once it's up to operating temp and with the engine still running see if the coolant in the radiator is flowing. May have to rev it up (2500 rpm) to get the coolant to flow better...if it's not flowing properly it could be a waterpump issue causing the temp to rise. Did the radiator you purchase come with a new cap?

bigtunadaboss

was a mishimoto so it did come with a cap. Also I can see coolant moving so I know water pump is working.

Wankenstein

When you did a coolant bleed after the radiator install did you follow the service manual?
1) raise front end on jacks high as possible
2) set climate control to max heat and fan off
3) bleed until air bubbles are non-existent at idle
4) fill radiator and reservoir to proper level after engine cools

bigtunadaboss

yes I did. I was having this issue before the radiator but I figured it was time for an upgrade.

Wankenstein

With everything else considered it's pointing to a head gasket breach. Have you checked compression recently?..If not it's good to do one before removing the head just to ensure there isn't a deeper issue to consider than just replacing the head gasket.

bigtunadaboss

no I have not check compression. Would a blown headgasket cause the fan to not come on? I could see how it might cause an air pocket

Wankenstein

Possibly, but I'm not sure. If you end up replacing the head gasket it may solve the fan engaging issue? Can always leave it jumpered.

Wankenstein

These may help:

https://www.thoughtco.com/signs-of-a...gasket-4148136

https://mechanics.stackexchange.com/...kets-are-blown

CMDR Karos

Dn my D16Y8 my fan wouldn't come on because I had this buildup of residue on the end of the sensor. I pulled the sensor out of the thermostat housing and took some 350grit sand paper to it and polished it up. It worked fine after that. Also my fan rarely ever turns on. Usually goes on when I hit 210-220F but I use an OBDII reader to measure exact temp. Also your temp guage can't measure steam, only liquid so made sure your system is properly bled out.

bigtunadaboss

Well I got the fan working, the connector was being funky and I just wiggled it around and it turned the fan on. Too late now thought as the first time it must've happened the HG blew. Today was overhating while driving down road. Pulled over and turned car off and then put it to run to get the fan on to cool the radiator down, checked the coolant and it was full. Turned car on and coolant was coming out of radiator and as I revved it more coolant was shooting out with RPM's. Only use a honda HG or is a fel-pro one fine?

Colin42

Only use the Honda one, people have reported problems with the aftermarket ones

bigtunadaboss

Besides doing timing belt and water pump and tensioner is there any seals I outta replace or a engine seal kit? Already ordered a honda rear main and cam seal

Colin42

Valve cover and spark plug tube seals? Basically anything you take apart you should consider replacing the seal, unless it's been done recently.
Should get the head checked out as well

CMDR Karos

I used felpro and haven't had issues.


D16Y8