overheated /purged coolant /otterstat help

[glockworks21]

went for a short 10 minute drive and turning into neighborhood noticed temp was at the first red line. Pulled into drive heard the gurgling and realized coolant was dumping everywhere. Realized that the fans were NOT running.
I let it cool enough to get hands in there and pull wires from otterstat switch. I jumped them with a wire and the fans started running. (with the car off)

Is it safe to say that the switch is bad? Is there something else i should be checking?
If so does anyone have the new style pipe/switch from DGO that has the screw in switch? would that be a good upgrade and what else should i do just to be safe?
I am hoping nothing was damaged getting that hot for a short period of time. any advice on what i should do next would be great.

thanks
Dave

[AugustneverEnds]

I'd replace the otterstat, it sounds like it has failed. Your engine should be ok if you shut it down as soon as it began boiling the coolant. When you refill the cooling system you will have to bleed the air out unless you have a self bleeder kit installed.

I do not have the screw-in otterstat pipe but I plan to buy it and install this winter. I've never thought the OEM push and clip was the best design.

[glockworks21]

went for a short 10 minute drive and turning into neighborhood noticed temp was at the first red line. Pulled into drive heard the gurgling and realized coolant was dumping everywhere. Realized that the fans were NOT running.
I let it cool enough to get hands in there and pull wires from otterstat switch. I jumped them with a wire and the fans started running. (with the car off)

Is it safe to say that the switch is bad? Is there something else i should be checking?
If so does anyone have the new style pipe/switch from DGO that has the screw in switch? would that be a good upgrade and what else should i do just to be safe?
I am hoping nothing was damaged getting that hot for a short period of time. any advice on what i should do next would be great.

thanks
Dave



meant to say pulled into driveway.. so it was not boiling over too long before i shut it off...

[iflights]

You can now get that same screw-in pipe with new otterstat directly from DMCH. Part K110131A.

[glockworks21]

went for a short 10 minute drive and turning into neighborhood noticed temp was at the first red line. Pulled into drive heard the gurgling and realized coolant was dumping everywhere. Realized that the fans were NOT running.
I let it cool enough to get hands in there and pull wires from otterstat switch. I jumped them with a wire and the fans started running. (with the car off)

Is it safe to say that the switch is bad? Is there something else i should be checking?
If so does anyone have the new style pipe/switch from DGO that has the screw in switch? would that be a good upgrade and what else should i do just to be safe?
I am hoping nothing was damaged getting that hot for a short period of time. any advice on what i should do next would be great.

thanks
Dave

Im going to order from dgo or dmc tonight. Is there something else i should be checking? The car was only running for about 10-15 minutes before it started boiling over. It was about75 degrees outside. Does it seem like it heated up to quick for just the fans not running in that short of a period of time?

[WHO1DMC]

Im going to order from dgo or dmc tonight. Is there something else i should be checking? The car was only running for about 10-15 minutes before it started boiling over. It was about75 degrees outside. Does it seem like it heated up to quick for just the fans not running in that short of a period of time?


My guess is air in the system. If you haven't done anything to possibly cause it. The water pump could be going or not a good pipe seal on one of many pipes. Air trapped in the water pump will cause it to fail sooner because it sits above the water column.
This is why myself and others have installed the auto bleeder system.




Dave B.

[AugustneverEnds]

Im going to order from dgo or dmc tonight. Is there something else i should be checking? The car was only running for about 10-15 minutes before it started boiling over. It was about75 degrees outside. Does it seem like it heated up to quick for just the fans not running in that short of a period of time?

If the car was stationary (no airflow passing through the radiator) and no fans spinning for 10-15 minutes, for sure it will overheat.

Besides replacing the otterstat common sense says to check for any leaks. If you have an inspection camera or have access to one it take a peek under the intake for any coolant there. Check the weep hole under the shaft of the water pump, any drip there means the pump is toast.

[glockworks21]

dont see any leaks. weep hole is dry. I ordered the new style pipe and threaded sensor from Dgo along with hoses clamps and a self bleeder kit. I appreciate the help and will update when i get it together.

[David T]

There are many reasons the fans don't run when they should. A little trouble-shooting and visual inspection is in order. Inspect the fuseblock for signs of overheating. Inspect the fan fail relay or whatever you have in place of it. Check with a meter the circuit breaker for the cooling fans. If that all is good use a paper clip or a clip lead and jumper the two wires going to the Otterstat switch. If that doesn't get the fans to run you need to use a meter and find where the circuit is failing or it's possible the fan motors are bad (or the wiring to them). It is "Good Practice" to replace the "O" switch anytime the car got too hot, it often damages the "O" switch so it no longer works correctly once it gets overheated. It is also a good idea to bleed the system because it probably has air in it once it boils over. If the system hasn't been flushed in a long time (over 5 years) now is a good time to do it. Replace with Prestone and mix with 50/50 soft water unless you buy the pre-mixed stuff. You should pressure test for leaks while you bleed the air out.

[glockworks21]

I replaced the pipe and sensor a couple hoses and added the bleeding kit. There was a leak at one end of the bleed valve that was hissing air and a bit of coolant. I swapped the hose clamps to smaller ones than what they supplied and it stopped leaking and looked a lot cleaner. everything seems to be working. The fans kicked on like they should. Ive let it heat up and cool down twice. cant find any leaks so far.
Is it best to just leave the bleed valve open all the time? Is that what everyone does with this kit?

Thanks for all the help.

[WHO1DMC]

I replaced the pipe and sensor a couple hoses and added the bleeding kit. There was a leak at one end of the bleed valve that was hissing air and a bit of coolant. I swapped the hose clamps to smaller ones than what they supplied and it stopped leaking and looked a lot cleaner. everything seems to be working. The fans kicked on like they should. Ive let it heat up and cool down twice. cant find any leaks so far.
Is it best to just leave the bleed valve open all the time? Is that what everyone does with this kit?

Thanks for all the help.

Glad everything is going better! You leave the valve open all the time it's only closed for pressure testing.



Dave B.

[glockworks21]

Just realized that only one of the fans is spinning....
soooooooo

[82DMC12]

I don't think it really matters too much if the bleeder is open or closed. Technically the car should run hotter if the bleeder is open because the hottest coolant is bypassing the radiator and returning to the expansion tank continuously but I have never measured this.

I didn't have a bleed valve for many years but I did add a ball valve last year after an overheating incident. Sometimes I check to make sure the thermostat is bled off so I'll let the car warm up and get hot, open the valve, hold the black hose until it's burning hot, then close the valve again. That way I can be sure all the air is out.

One way you can increase the reliability of the original otterstat clip / push in otterstat is to tighten a zip tie around the clip so it can't pop off. Pretty rare for the clip to fail though, unless it rusted away.

[glockworks21]

Thanks Andy, I took it out for a longer run today with the valve open and both fans now working. (i made a jumper for the relay. Mine had nothing in it) Im coming up on a year now and still finding problems and learning. Anyways it stayed at 160 or slightly below with mixed driving of highway and stop and go through town. So far so good..
I replaced with the newer style o valve that threads in from DGO. seems to be a good design.

[Bitsyncmaster]

Thanks Andy, I took it out for a longer run today with the valve open and both fans now working. (i made a jumper for the relay. Mine had nothing in it) Im coming up on a year now and still finding problems and learning. Anyways it stayed at 160 or slightly below with mixed driving of highway and stop and go through town. So far so good..
I replaced with the newer style o valve that threads in from DGO. seems to be a good design.

If your fan fail socket had nothing in it and the fans were still running, someone has done wiring modifications to the wiring to that socket.

[glockworks21]

If your fan fail socket had nothing in it and the fans were still running, someone has done wiring modifications to the wiring to that socket.

ugh.i wouldn't be surprised. everything seems to be working as it should. Nothing shorted out when I did the jumper. the fans both stay on with ac and when it hits 160deg. i will continue to take on short drives to test.

[glockworks21]

ugh.i wouldn't be surprised. everything seems to be working as it should. Nothing shorted out when I did the jumper. the fans both stay on with ac and when it hits 160deg. i will continue to take on short drives to test.

so today(one month later) the car temp started rising again. Lucky it cold out and i was near house. I checked the jumper wires on the fan control and one of the fuses was blown. I replaced it and still no fans. I disconnected the wires from otterstat and jumped them and both fans came on again. Do you think I just got a bad otterstat? Luck of the draw? Im wondering if it shorted out due to something else? Any thoughts on something else i should be looking at?


Thanks
Dave

[David T]

so today(one month later) the car temp started rising again. Lucky it cold out and i was near house. I checked the jumper wires on the fan control and one of the fuses was blown. I replaced it and still no fans. I disconnected the wires from otterstat and jumped them and both fans came on again. Do you think I just got a bad otterstat? Luck of the draw? Im wondering if it shorted out due to something else? Any thoughts on something else i should be looking at?


Thanks
Dave

The early cars had the "O" switch on top of the pipe and if an air bubble got caught there the "O" switch didn't work. The "improved" version turned the pipe over and put the "O" switch on the bottom. If you have the early version you should update it. The "O" switch can be bad. If you are blowing fuses you have a wiring problem to one of the fans or one of the fan motors is bad.

[glockworks21]

The early cars had the "O" switch on top of the pipe and if an air bubble got caught there the "O" switch didn't work. The "improved" version turned the pipe over and put the "O" switch on the bottom. If you have the early version you should update it. The "O" switch can be bad. If you are blowing fuses you have a wiring problem to one of the fans or one of the fan motors is bad.

i have it facing down.(the old one was as well) its all new. if there is a wiring problem would it burn out the new "o" switch? Its only a month old..

[AugustneverEnds]

It is possible the otterstat failed already. If it's NOS or something in your car's wiring might have killed it. I ruined a new otterstat when I dropped it while installing it.

[Ron]

so today(one month later) the car temp started rising again. Lucky it cold out and i was near house. I checked the jumper wires on the fan control and one of the fuses was blown. I replaced it and still no fans. I disconnected the wires from otterstat and jumped them and both fans came on again. Do you think I just got a bad otterstat? Luck of the draw? Im wondering if it shorted out due to something else? Any thoughts on something else i should be looking at?


Thanks
DaveIt would take a lot of amperage running through the Otterstat to blow it. A bad fan could do it. But I'm thinking you may have another problem as well and that Bitsy is on the right track... Try pulling both fuses and check if 1 fan runs when you short the two Otterstat wires together (Key at RUN). If so, see if it is the fan that the blown fuse fed or not before you change anything you might find allowing it to run.

[glockworks21]

It would take a lot of amperage running through the Otterstat to blow it. A bad fan could do it. But I'm thinking you may have another problem as well and that Bitsy is on the right track... Try pulling both fuses and check if 1 fan runs when you short the two Otterstat wires together (Key at RUN). If so, see if it is the fan that the blown fuse fed or not before you change anything you might find allowing it to run.

I did this and when i pulled one of the fuses from the relay nothing changed(both fans kept going) when i pulled the other fuse one fan shut off and the other one kept going
i looked at the wiring to the fans and can see a splice and some wire ties ect that have been added so i know its been messed with. there is also a green relay with a empty connector. Im sure to one of your trained eyes you can see whats been hacked. maybe someone can give me an idea what to change back.. im confident that the po took this to a shop when the oem fan relay failed and they did whatever bs job they could to make one of the fans work.

I am overwhelmed with the support that you guys have given. I have done everything myself on this car. It was a runner when i got it and l have a half ream size stack of receipts of well over 30k that came with it. but it sat for years after all that work.
i tallied up my Dgo receipts for the last year at $2500 and another $500 or so from dmc and have done everything myself. Im learning as i go. I guess the biggest frustration is finding things that have been done wrong. many were obvious an i corrected quickly. some like this fan issue were not obvious and only showed when the car boiled over.
Rant over.. Thanks everyone. I hope in a couple years i can start giving advice.


thanks again and i hope this mess helps others out there..


Dave

[WHO1DMC]

Looking at the fan motors in the pictures I think it's time for them to go. A few years ago I did mine and it definitely made things better. The old fan motor wires were getting bad and hard telling what the windings looked like. I had the melting problem with the common fused wires that replace the original blue relay. I also whent with Dave McKeens fan fail relay. In my opinion is a must.
It is possible to get the fans and shroud out with the radiator left in place by yourself. It's a pain so if you have some help it would definitely be better. Going back in with new fans not that much of a deal. The biggest thing is that it's less stress on the electrical system because they use less power.


Just an observation.
Dave B.

[Ron]

I did this and when i pulled one of the fuses from the relay nothing changed(both fans kept going) when i pulled the other fuse one fan shut off and the other one kept going...
Just to be sure before going further, you are talking about the two fuses in the fan fail relay's SOCKET (lower left in the pic below), not an aftermarket unit etc., correct?
69217

If so, check if there are any obvious modifications to the socket's wiring.

Use the pic below to help check the other wiring.
69218

[glockworks21]

Just to be sure before going further, you are talking about the two fuses in the fan fail relay's SOCKET (lower left in the pic below), not an aftermarket unit etc., correct?
69217

If so, check if there are any obvious modifications to the socket's wiring.

Use the pic below to help check the other wiring.
69218


yeah the fuse on the jumper wires in the blue relay(pic) Im going to see if i can identify any obvious modification later this week. i will share what i find. Im waiting on new otterstat also.

Thanks again..

[Ron]

yeah the fuse on the jumper wires in the blue relay(pic) Im going to see if i can identify any obvious modification later this week. i will share what i find. Im waiting on new otterstat also.

Thanks again..I'm seeing fuses in a socket, no relay???

I don't recognize the green relay in the last two pics in post 22. (Anyone else?)

[WHO1DMC]

I'm seeing fuses in a socket, no relay???

I don't recognize the green relay in the last two pics in post 22. (Anyone else?)

It looks like a random relay but there's also a black one next to it.
I'm thinking the fans were pulling so much current they connected relays to them with a main power wire. So if that is the case then the fuses are offering no protection.



Dave B.

[Ron]

It looks like a random relay but there's also a black one next to it.
I'm thinking the fans were pulling so much current they connected relays to them with a main power wire. So if that is the case then the fuses are offering no protection.



Dave B.Yeah, sounds about right.

Probably best to strip everything off up to the OEM harness and start from there.

[glockworks21]

Yeah, sounds about right.

Probably best to strip everything off up to the OEM harness and start from there.

pulled the tape off and this is what i found...
thoughts on what to do with this?
im thinking of ordering 2 new low draw fans from dmc. can they be installed without removing radiator?

[glockworks21]

pulled the tape off and this is what i found...
thoughts on what to do with this?
im thinking of ordering 2 new low draw fans from dmc. can they be installed without removing radiator?

another pic

[glockworks21]

one more.. got most of the tape off..

[Ron]

pulled the tape off and this is what i found...
thoughts on what to do with this?
im thinking of ordering 2 new low draw fans from dmc. can they be installed without removing radiator?
Since it's been hacked so much, I'd check the wire arrangement at the Cooling Fan Relay Socket. Then its wire (may be Black/Orange or Brown/Orange) to the 40 Amp Thermal Breaker. The other breaker wire may be Brown/Slate, or, Black/Orange. It should feed the Fan Fail Module Socket. Check the arrangement of its wires. Borrow one of the other 03332-204-151 relays known to work (eg. high beam) for the Cooling Fan Relay Socket. Then jump the Otterstat Plug to check the harness at the Fan Connector Plugs for power and ground. Check the amp draw for the fans to see if they are worth keeping.

New ones are always nice. :smile:

[glockworks21]

i just unplugged both of those relays (8 wires) one at a time while the fans were both running (jumped wire on otterstat)
only one of the 8 wires pulled made any difference in the fan speed. they slightly slowed but both kept running.
I then went and pulled the fuses one at a time from the jumper i made in the empty blue fan relay and each one now controls a fan(which it didnt before)

all this mess instead of a jumper for the blue fan relay???

I think im going to tidy up the spliced wires and get them back to oe. i dont think they ran anything additional or messed with factory wiring in other relays.

[David T]

The fans should not change speed. They are either on or off. You may notice a change in the noise but that is due to voltage changes. You should either have the double-bypass replacing the blue fan fail relay (with or without in-line fuses) or an aftermarket relay like the Fanzilla or Dave's relay. It is possible a connector backed out of the fuseblock and you aren't getting good connections or someone may have switched around connectors in the fuseblock. It is important you have good, solid, tight, connections. This circuit has a very high current draw and anything that is not 100% is going to overheat and fail. A lot of owners have switched to lower current drawing fans like Spall to reduce the current draw. This circuit draws so much that when the fans start up you can actually feel it in the gas pedal. That's why the aftermarket relays have a built-in "soft start" so both fans don't start at the same time.

[Ron]

I agree, the fans shouldn't have slowed down. Maybe that's what they were trying to solve...

(Don't forget the grounds;-)

[glockworks21]

anyone know if this is factory wiring? its where all the relays were spliced in to..
2red and one blue wire coming out by fans

[82DMC12]

anyone know if this is factory wiring? its where all the relays were spliced in to..
2red and one blue wire coming out by fans

There shouldn't be any relays or anything spliced into the front frame harness. It should be nothing but wrapped wires terminating at two 2-pin plugs, which then plugs into each fan. You might want to remove the electrical tape and keep going back to the main trunk until you find where that new wiring was spliced in. Remove that splice and then re-build the fan wiring using heat shrink marine butt connectors and 12-14 gauge wire. Might want to consider updating the plugs to weatherpack connectors while you're at it.

https://youtu.be/k0NAIge1n6Q?t=230

[glockworks21]

I know this is a long shot with this pic. I cant find diagram of how these relays are supposed to be connected. I bypassed the circuit breaker with that red wire just to test.

when the o switch is jumped the fans work. ive swapped the relays out and replaced the o switch again and it makes no difference. The fans wont kick on when the car warms up. they work with the ac. I cant figure out how this was hacked. Is there something else that sends signal to start fans when car hits temp?

[Bitsyncmaster]

I know this is a long shot with this pic. I cant find diagram of how these relays are supposed to be connected. I bypassed the circuit breaker with that red wire just to test.

when the o switch is jumped the fans work. ive swapped the relays out and replaced the o switch again and it makes no difference. The fans wont kick on when the car warms up. they work with the ac. I cant figure out how this was hacked. Is there something else that sends signal to start fans when car hits temp?

Your correct in testing the jumped otterstat and fans run. AC on and fans run. There is nothing else for getting the fans running. Is your otterstat pointing down (terminal facing the ground)? You must have an air pocket keeping the otterstat from getting heated.

By the way it looks like the PO had a ground problem and melted his relay grounds. I sell a front relay ground buss if your interested.

[Ron]

I know this is a long shot with this pic. I cant find diagram of how these relays are supposed to be connected. I bypassed the circuit breaker with that red wire just to test.

when the o switch is jumped the fans work. ive swapped the relays out and replaced the o switch again and it makes no difference. The fans wont kick on when the car warms up. they work with the ac. I cant figure out how this was hacked. Is there something else that sends signal to start fans when car hits temp?I posted the wiring (post 24 (https://dmctalk.org/showthread.php?19500-overheated-purged-coolant-otterstat-help&p=274044&viewfull=1#post274044)).

[glockworks21]

i just took it around block. its just over 220 degrees and no fans. But now realize that both main hoses going to water pump are cool to touch. Is it possible something is restricting flow? the coolant is not hot....

[AugustneverEnds]

Air, lots and lots of air.

[glockworks21]

Air, lots and lots of air.

You are 100% right! After the last post I went out and removed that auto bleed system and bleed it out of the theromostat housing. Made a huge mess but was able to get it flowing. I need to replace some hose links near the radiator so I will be doing it all again but its all working now.
my luck that i had 2 issues at same time with the shorted out fan system

Thanks everyone.
I still dont know where that wire runs to. Im capping it off and letting it ride for now...

[AugustneverEnds]

Glad you got it working :thumbup2:

The D's cooling system is genius at trapping air, sometimes you need several bleeds to purge it all.

Better it's air and not mineral build up because then you'd have a lot of flushing with dish detergent ahead!

[Ron]

Cool beans!
(You might try pulling one fuse at a time to get a clue for the mystery wire.)