1994 Overheats with AC on (1 Viewer)
- Thread starter vinlc562
- Start date
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I would definitely put a timing light on it and check ignition timing via the fsm since you said that you haven’t checked it since the HG.
Side note, I had nothing but trouble with the brass CSF radiators that I purchased. My 80 would consistently overheat with the one I purchased and the one that was warrantied. I put an OEM rad back in my 94 and it’s solved the overheating issue. I’m running a 94 with 35’s and an Aisin OE replacement fan clutch from cruiser outfitters with no fancy mods. It has not overheated since (30k miles). 518k miles on that engine.
Side note, I had nothing but trouble with the brass CSF radiators that I purchased. My 80 would consistently overheat with the one I purchased and the one that was warrantied. I put an OEM rad back in my 94 and it’s solved the overheating issue. I’m running a 94 with 35’s and an Aisin OE replacement fan clutch from cruiser outfitters with no fancy mods. It has not overheated since (30k miles). 518k miles on that engine.
Prob not a bad idea to also install a scangauge to monitor your ECT.
- Thread starter
- #25
Is there Scangauge for OBD1?
- Thread starter
- #26
Yes, I’ve check the coolant level and it did changed from cold to hot to cold and did that 1-2 inches. At first, when I got my 80 I thought something is wrong but as the days goes by consistently checking I guess its normal for it to do that when engine hot and cold but anyways no coolant loss.
OK. It's normal for the coolant level in the overflow tank to change (go up when engine is warmed up) 1-2 inches then go back to the original level in the overflow tank once the engine is shut off and cools down.
What I was getting at is that with a leaking head gasket (or even cracked cylinder wall in my case) the cooling system may get over-pressurized with exhaust gases that blow past the head gasket and that can force coolant out of the water jacket in the block into the radiator then into the overflow tank and then out onto the ground.
So if the coolant level (cold engine) starts at the correct level, assuming the radiator/system is full and the level in the overflow tank was at the FULL mark to start, then goes way overfull in the overflow tank (like to the top) while driving along with overheating, that might indicate a leaking head gasket or something worse (cracked block/cylinder) .
What I was getting at is that with a leaking head gasket (or even cracked cylinder wall in my case) the cooling system may get over-pressurized with exhaust gases that blow past the head gasket and that can force coolant out of the water jacket in the block into the radiator then into the overflow tank and then out onto the ground.
So if the coolant level (cold engine) starts at the correct level, assuming the radiator/system is full and the level in the overflow tank was at the FULL mark to start, then goes way overfull in the overflow tank (like to the top) while driving along with overheating, that might indicate a leaking head gasket or something worse (cracked block/cylinder) .
Of course under these circumstances, you don't want to assume the radiator is full, which I'm sure is not what Kernal is saying here. You want to check that it is.
From a dead cold engine, open the cap. If it's full to the top, you're OK. However, if overheating it is possible that you'll lose enough coolant that once the engine is hot, the coolant won't rise high enough to maintain the siphon action that moves the overflow tank level up and down as is usual. This can lead to a false sense of security, with coolant in the overflow seemingly indicating there's plenty in the radiator - when there's not. If the radiator coolant level isn't full to the top, top it off and this will ensure that it re-establishes the siphon action.
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- Thread starter
- #29
Do it right:
Modified 95 Degrees Fan Clutch, 80 Series Heavy Duty - 1FZ-FE Blue Hub Fan Clutch Mod
Modified Fan Clutch for the 80-Series 1FZ-FE. This Fan Clutch will engage at 95 degrees, earlier than factory specifics. (Optional) V-Belt Set; Fan & Alternatorredlinelandcruisers.com
The overheating issue has been solved. I ordered this one and everything is good. I was trailing at 106-108 degree weather and didn’t overheat. I installed aux fan just incase but didn’t end up needing it.
Thanks everyone that were involve with this.
CSF is your problem plus heat wave. might look into weak fan clutch. Wheeling with AC off...
- Thread starter
- #31
Problem solved. CSF is not the issue, it was the fan clutch.
easy fix. Get a real time temp reader other than the stock temp gauge. 3/4 to full indicates 230 plus coolant temp. which would be a disaster for the 1FZ
- Thread starter
- #33
Do you have link? I have OBD1.
For us OBD1 you will need Toyobd1 scan gauge. Or do what most of us did, attach a sensor that reads coolant temp. You will need to cut the upper rad hose and attach a hose fitting so that the temp sensor could tapped into.
Search MUD forum....
DEWHEL Aluminum Black Water Temp... https://www.amazon.com/dp/B018FY12CW?ref=ppx_pop_mob_ap_share
Trail Tech 742-ES2 TTO... https://www.amazon.com/dp/B07D9VYCP6?ref=ppx_pop_mob_ap_share
OR:
zf-scantools.com
Search MUD forum....
DEWHEL Aluminum Black Water Temp... https://www.amazon.com/dp/B018FY12CW?ref=ppx_pop_mob_ap_share
Trail Tech 742-ES2 TTO... https://www.amazon.com/dp/B07D9VYCP6?ref=ppx_pop_mob_ap_share
OR:
OBD1 Scantools
zf-scantools.com
Toyobd1. Can read ECT, and your ECU signal.
Post in thread 'Toyocom OBD1 Bluetooth available again' Toyocom OBD1 Bluetooth available again - https://forum.ih8mud.com/threads/toyocom-obd1-bluetooth-available-again.1136285/post-15099591
- Thread starter
- #38
Looks nice, do you have link for this?
- Thread starter
- #39
Thanks, I’ll check it out!
- Thread starter
- #40
Hey, do you have pics on how your wired this?
