- This topic has 23 replies, 5 voices, and was last updated 12 years, 3 months ago by
.
-
Topic
-
-
Replies
-
Auto parts stores sell it. You won’t believe the worlds of difference it makes when bleeding yer system. I’d almost put money on that being your problem. I’m thinking you might be confusing fan speeds with one fan being on versus both (if is has a separate condensor fan, which is probably does). The noise level will be much higher when both fans are on instead of just the one. My Toyota Rav4 sounds like a jet getting ready to take off when both fans run, it’s pretty embarrassing when you’re trying to place your order at Taco Heck and the other fan kicks on and the girl can’t hear you over it.
The steps are pretty much outlined in the video, you don’t want to jump to conclusions or make assumptions so see if you can get your hands on the required tools to do your diagnosis.
I can’t stress enough however that air in the system is the most common cause of overheat issues. Bleeder valves are only there to make filling the system easier you still need to do the rest of the procedure outlined in this video to successfully remove the air from the system. You don’t NEED the funnel but it does make life easier, you can just as easily put a catch pan under the area to catch any coolant that boils over during the process.
http://www.youtube.com/watch?v=zUpXgAJ1gjU&feature=relmfuI found the wiring diagram and it show 2 wires coming off the PCM saying fan 1 and the other saids fan 2 . does anyone know if this van have 2 speeds for the cooling fans? i am at a lost why it still overheats?
the only thing i have not replaced is the water pump and the thermostat i don’t think thoses are my problem. i did the block test and that came up ok ( i dont think i did that test wrong) i bleed the air out of the system. my cooling fans DO turn on 2 marks after the halfway point on the temp gauge how they are running on low speed and not high.
any other ideas?
thanks
ohhh yes when the fans are on low speed both fans are running i can see that ( well unless it turning due to the air flow from the other fan) and i can trick the fans to run “low” speed or “high” speed but either way i should hear it turn on BOTH fans when it needs to right? if that is the case i only hear the one fan or low speed. i did test the fans relays,fuses all are good. at what temp should both fans be on??
thanks
when the van goes to over heat. if you turn the
heat on full hot does the temp gage return to normal?
if it does I would suspect the t-stat not opening all
the way. or radiator issue the easiest thing to try
is a new t-stat. If you lower the coolant in the
radiator and with the cap off can good flow be seen?I hate to keep pointing this out but much of what you are asking is covered in the original video that posted for you as I go through step by step what to check when you have an overheat condition. That said the break down is like this:
1. purge the air out of the system. Bleeder valves have NOTHING to do with purging the air they just make filling the system easier, to properly bleed the system follow the steps in the video I posted on the subject.
2. Check for leaks with a pressure tester AFTER you know all the air is out of the system, if not and there is still air in the system the test will not be accurate. Pressure should hold for about 10 min or so but to be honest it’s probably going to leak more at the connection where you installed the tester but the idea is to LOOK for leaks during this time OR for dried green residue that could indicate seepage of coolant.
3. Check the cooling fan operation, if they work and turn on as you would have verified during the process of bleeding the air out you should be fine.
4. Check for debris blocking airflow through the radiator, you may need to separate it from the condenser to see if there is any debris between the 2. Also make sure you have a fan shroud, if the fan shroud is missing this will compromise airflow and the fan will not work as efficiently as it should.
5. Check for a combustion leak into the cooling system with a block tester. If you find one DON’T assume it’s a head gasket as it could also be a cracked block or cylinder head, the truth is that you won’t know till you take it apart.
If you do all of the above checks and still have an overheat issue there could be a problem with coolant flow through the system such as a restriction in the radiator or engine block OR a problem with the water pump not moving enough of a volume of coolant.
Lastly if the engine timing is off this can cause an overheat, also verify that the temperature gauge is working, the engine could be fine but the gauge could read wrong.
yes that is what i did as to what u posted and what the video saids. i did the purge the air out of the system well at least i think the air is out. and i did it the way the video saids . i will recheck and do the pressure test again cause i did the pressure test when there was air in the system and it was low on coolant
thanks
- You must be logged in to reply to this topic.