Sidethumper

iTrader: (1)

I have a long single dark green wire with a spade connector coming out of the harness along with the two plug tranny wire. Anyone have any idea where this goes? There is no place that I can see where it hooks to the tranny but yet it comes out of the same area. Thanks

Sidethumper

iTrader: (1)

Ok I will give some more info, the wire is a key on power wire but its only showing 11.8 volts. I get 12.4 to 12.8 volts everywhere else. Kind of weird but I still don't know where it goes and why it comes out at the same place as the transmission wires.

Anyway If this wire is not important to the transmission I would like to use it for the electric choke. Heck maybe that is what it was for before?

BigBadLou

iTrader: (3)

The only single dark green in the engine harness would be for the temperature gauge sensor which is in the driver side head, between the first two spark plugs.
You can check whether your temp gauge shows anything. If it shows full hot, that would be very likely due to the wire being disconnected.

Let us know what you find
Lou

Sidethumper

iTrader: (1)

Well it does not show full hot. When I turn the key the pointer on the temp gauge moves just a tiny bit. The green wire is not hooked up.

Another question... what sensor is on the other side of the block between #6 and #8 plugs is that the temp sensor location for electric fan?

BigBadLou

iTrader: (3)

On the passenger side, that's an overheat temp switch in the head. It turns on the secondary cooling fan in case the engine reaches dangerously high temperature (I don't recall exactly but is is around 240*F).

Do you have some resistors laying around? You could try a few kilo-ohms to put between the green wire and ground and see whether the gauge moves.

I realize now that I made a mistake earlier. When the wire is disconnected, you will see full cold on the temp gauge. When the wire is grounded, you will see full hot on the gauge. Sorry about the mishap.

Sidethumper

iTrader: (1)

I do not have any resistors... where and what do I need to get?

I put a regular temp sensor in the passenger side not knowing, but then I bought a 3 gauge setup oil , temp , and volts and installed it on the driver side. I am thinking of going with a mechanical fan, the car came with a single electric fan but I can't get it to fit properly. It just seems really cheap plastic . So now I do not know what to do with the passenger side hole... I guess just plug it.

I wanted to be able to get all the stock gauges working properly but I don't know what wires are what lol.

BigBadLou

iTrader: (3)

If you are absolutely positive you have the right dark green wire, you can simply touch it to ground and the temp gauge should come up to full hot. I was suggesting the resistors to avoid any potential damage if the dark green wire is not the right one. If it is, you can skip the safety step with resistors.

Single electric fan? That's TBI equipment. 1987 TPI cars (IIRC) came with dual fans already. The single fan on TBI cars is controlled by a temp switch installed in the passenger side head, your empty hole. You might want to consider a lower temperature switch, though, than the stock one which is around 238F.
I would strongly suggest keeping the electric fan. It runs only when it needs to run and doesn't rob you of horsepower. And it does not "howl" when you start the car up cold, like the mechanical fans do.

If you have any questions about the gauge wiring, just ask, that's what we're here for.
Or you can refer to a good set of diagrams that I compiled here.

Hope this helps.
Lou

Sidethumper

iTrader: (1)

I am not 100% sure of anything on this car as Im learning as I go lol . I have been looking for someone to coach me with this build from day one. As far as the electric fan goes I don't even know how to wire it up. I guess that is one of the reasons I was going to do mechanical fan. I don't know what to do man Im at a loss here.

So anyway here is a pic of the old 305 .... It looks like a carb to me...



And this is what I have today...

Sidethumper

iTrader: (1)

Its not a super high performance build just a mild 350. I always liked an old school look to the engine and that is one of the reasons I did carbed.

Keeping the electric fan would be cheaper for me but I would have to figure out why its not fitting correct and then figure out the wiring.

BigBadLou

iTrader: (3)

If the fan is not fitting right, I would check whether the radiator is maybe an aftermarket part.
Once the fan bolts on, you can use the stock wiring and relay to control it, no problem. It will run with A/C on and when the engine gets hot (you can control the temperature based on what switch with temp rating you buy).

The old 305 in your picture has what seems like the last year of the CCC (computer controlled carburetor) system on it, those did come with at least one fan so as long as you have the old wiring, you will be fine with the electric fan. Check out my cooling fan troubleshooting page and see if your circuit is missing any components and wires.
http://www.austinthirdgen.org/index.php?pid=36
That year also came with an electric fuel pump. You can see the troubleshooting article here: http://www.austinthirdgen.org/index.php?pid=35

Let us know what else you need.
Lou

Sidethumper

iTrader: (1)

It had a mechanical fuel pump on the side of the block? Please tell me I have a sending unit in the tank and not a pump in the tank

BigBadLou

iTrader: (3)

A mechanical pump? Hmm. It was not the stock block then. *scratch chin* The CCC engines were supposed to have an electric fuel pump in the tank.

You can easily check how many wires go to your tank. If you are thin, you can slide under the rear bumper from the driver side, right behind the rear tire. Look up above the differential and there should be a connector C313 on the fwd wall (the back seats lean against it). If you have 2 wires black and pink, those are for your fuel sending unit only and you probably don't have an in-tank fuel pump.
The fuel pump used tan/white wire so if you see that on your C313, that would indicate that there "might" be a pump in there but that's hard to conclude. You'd just need to put power on the tan/white wire and see if the pump whirs. That would be definite proof.

Let us know what you find.
Lou

Sidethumper

iTrader: (1)

Pink black and tan are the three wires going to the tank, The black wire is grounded under the rear driver side seat

Sidethumper

iTrader: (1)

As far as the electric fan goes, did the ecm control that because I have taken out the ecm and all the harness.... Another reason I was going to use the mech fan

BigBadLou

iTrader: (3)

Apply 12V to the tan/white wire and listen for the pump whir. Or if you have a DMM, you can measure the resistance on the tan/white wire on the tank side (disconnected from the car wiring). If you see any resistance (probably less than 10 ohms), you have a pump in the tank.
Which is a GOOD thing.

BigBadLou

iTrader: (3)

Nope, the ECM does not control the fan on the old CCC or TBI.

The fan is controlled by two triggers (via the relay). The first one is the overheat switch in the passenger side head, the second one is the A/C switch.

You can use the current wiring harness to work the electric fan.

Sidethumper

iTrader: (1)

Thanks Lou for taking some time to school me, I was doing some different searches and found out the answer to the ECM question. My problem with the fan was after mounting it the blades were rubbing at the bottom so I maneuvered it and pulled it so I finally got it to stop rubbing as it spun but just barely. These fans just seem so dang cheap IMO.

I will check that tan wire for the fuel tank in the morning, its storming out here right now. Thank you I suppose an extra pump in the tank would not be a bad thing lol. When I turn the key on the 12v should make the pump whir right? I don't hear anything when I turn the key. What is a DMM? Digital muti meter? I have one in the pic below but never used it other then checking volts and continuity. I will have to figure out what setting to use to check ohms, never done that one before.

So here is the long harness that has the fan plug on it. Can you tell me what the two boxes that appear to be relays are for? they were both attached to the engine bay near the battery when I took the car apart. Im trying to find them on the diagram. Since I am not running duel fans do I still need a overheat switch in the passenger head? I was reading in your post #10 link where that switch kicks on the second fan in overheat situation? I am going to use your troubleshooting guide tomorrow... thanks, but I cant read the diagram very well to see if I am missing anything in that circuit. I need to try and get it to come up bigger on my screen . I was also reading where people were putting in a toggle in to control the fan manually but I would love to get the fan working properly on its own.



Here is a closer pic. The box on the left is in need of some TLC every wire going into it has almost an inch of bare wire showing and touching each other.



Sorry for bombarding you with what seems to be dumb questions, like I said I am still learning all of this. I'm not good with electrical at all. I was asking a question in another thread about the relay cluster above the brake booster here https://www.thirdgen.org/forums/elec...ml#post5570825 to find out what one is the relay for the fan.

BigBadLou

iTrader: (3)

Lucky dog!

I didn't mean to imply to use two pumps, btw. The mechanical pump on the block is sufficient for the carb but then you have to drop your tank and remove your current pump. The electrical in-tank pump, however, would help you prime the carb bowls before even cranking the engine over. You could re-use the original pressure regulator if there was one on the old CCC engine.

According to the diagram for CCC engines (which I have never worked on personally, so I cannot vouch for the correctness of the diagram in the first place), the pump is activated when the engine is being cranked over. And then the FPOP switch powers the fuel pump when the oil pressure comes up (safety feature). If your wiring harness is still intact, you can disconnect the purple wire from the starter and try turning the key into the start position and listening for the fuel pump whir.

Yup, DMM = Digital Multi Meter, it can perform multiple types of measurements. You measured for continuity before, it's the same as measuring resistance. For your fuel pump resistance test, you simply select Ohms on the dial (or buttons), select range of ohms if it is not auto-range DMM, then you can measure the disconnected C313 (the tank side). Put one lead/probe on the black wire and the other lead/probe on the tan/white wire. If the DMM reads a few ohms, you have a pump. If it reads empty (usually something like 0L to indicate infinity), you probably do not have a pump or are not measuring it right.
Btw, Youtube has some good videos on DMM use. Pictures are worth a thousand words (and I sure typed a thousand already ).

The boxes do appear to be relays, however I would need the wire colors to identify their purpose. I a surprised that they are at the battery (TBI and TPI cars have them by the brake booster) but then again, this is a CCC car and I have never worked on one.

The overheat switch in the passenger side head is the only thing controlling the fan when it comes to engine temperature. So yes, you need some kind of a switch but it does not have to be in the head and it does not have to have the same temperature rating. (I got some 180*F universal switches sitting around, if you are running colder thermostat in your 350).

A good browser should let you magnify/zoom the picture. Usually Shift+=

The fan control circuit is no rocket science, yet people often try to control the fan manually or just hardwire it to the ignition. You are smart to keep it original and not have to worry about when to turn the fan on or off.

Yes, the insulation is so old, it gets brittle and crumbles apart, especially in high-stress areas, such as right by connectors. You can temporarily wrap each bare wire in el. tape but the wires should be cut and re-crimped into the connector pins eventually.

No dumb questions here.
To identify the fan relay, I will choose the "giving fish vs teaching to fish" approach here.
Ask yourself: what color wire is powering my fan? (answer in your picture ... and black is usually ground) Then look for that thick wire in the relay cluster. I don't guarantee the relay will be in the cluster by the brake booster, it might be one of the two relays by the battery.

Hope this helps.
Lou

Sidethumper

iTrader: (1)

Ok first things first, I followed your fan troubleshooting guide and located the relay for the fan which is in fact the white box on the firewall above brake booster. It has the Black/red (fan) orange (12 volt constant) brown (relay 12 volt keyed) and green/white (ECM)

20 amp fuse good, Orange good and good 12 volt on the brown when keyed. So I then jumped the orange and black/red and fan came on. Im not able to start the car at this time but my question is the relay good or bad? Since I am not able to bring the car to temp for the correct operation of the fan. I am going to go to the parts store and get the right switch for the passenger side head. Once I get that in is it just a waiting game until I can bring the car to temp? Also my engine builder told me to get a 160 thermostat... you said a 180 switch will work good with the colder thermostat right? And also since the ecm is gone what will the effect of the green/white wire be? Oh and my AC is deleted also will that switch have an effect on operation?

Wire colors of the two boxes in the pic above left side box = Pink/black stripe x 2, light green, blue and black.

right side box = light blue, tan/white stripe, brown/white stripe, black

I am going to check the tank next and see what happens. Edit: on the tank side the wires are black purple and grey? And no tan/white I checked ohms to the black and grey and it showed 5.8 Checked black and purple and was 0. (I sure hope I don't have to drop the tank) This CCC engine ran before I tore it apart. I was told since there was a mech. fuel pump on the block that I had a sending unit in the tank and not a pump but I guess I am going to figure it out with your help lol.

I will wait for a reply before I go get a switch for the passenger head.

BigBadLou

iTrader: (3)

Did you try grounding the green/white wire on the relay (with the key on)? If the relay clicks and fan turns on, the relay is good.

You do not need the ECM to control the fan (that is done only by the TPI ECMs). The temp switch is sufficient.

A 160F t-stat would work fine with a 180F fan switch. Mine is not the threaded style for your head, it is just a flat switch with two mounting tabs. So you can just leave the hole in the head plugged.

5.8 ohms on the grey wire sounds about right. It seems that you do have an in-tank fuel pump.

I will have to look at the relays and wire colors later, it is too late here and I am falling asleep, brain is refusing to work.

See ya
Lou

jwfirebird

iTrader: (2)

my fan was rubbing for a while i figured out that i was using the coolant crossmember to jack the car sometimes and it bent. i had to finesse it back into place with the bfh

naf

iTrader: (7)

The 87 ccc-qjet came with both an in-tank and mechanical fuel pump WITH return system. You'll want to keep both. The in-tank was added to help prevent vapor lock in the fuel lines which can be caused by a hot-soak. Your headers, if they run closer to the fuel lines than the stock manifolds, will make this issue worse. You may want to add some insulation to the lines as well.

BigBadLou

iTrader: (3)

naf, thank you for chiming in. I don't know much about the CCC engines so this helps.
What pressure did they set the FPR at for the mechanical pump? (I assume they used an FPR)

naf

iTrader: (7)

The mechanical pump has a built in return system. I've never opened one but the consensus is that it uses a metered orifice.

The in-tank pump is a low pressure pump. It is not intended to feed the motor alone. I measured mine once at between 1 and 2 PSI, maybe.

The Carter 6626 comes highly recommended as a replacement mechanical pump, and only around $14 through RA.

Make sure the in-tank is functioning, you can jump the relay. A bad in-tank will cause a restriction and you want to keep it to help prevent vapor lock.

BigBadLou

iTrader: (3)

So it might be a good idea to take the original mechanical pump off the old 305 and put it on the new 350 block? I assume the pump is a common part for the 305 and 350 so it should be able to feed the 350?

Thanks
Lou

Sidethumper

iTrader: (1)

Thanks for all the helpful info. The mech pump on it now is for a 305. I will have to give it a whirl and see what happens as far as fuel goes. I will try your relay test later after work...thanks Lou and others for educating me. If I'm not mistaken I think I tried that test and nothing happened.

naf

iTrader: (7)

The mech pump for the 305 is perfectly fine for a 350.

Sidethumper

iTrader: (1)

Yea they both take the same pump. Thanks. All I need to know now is what them two relay boxes are in the pic above and I should be all set. If I don't need them I want to delete them.

BigBadLou

iTrader: (3)

Sorry, I dropped the ball on this one. Been incredibly busy switching groups at work and trying to get my car ready for a painter in what free time I have.

The box with the light green wire (for simplicity) is the throttle kicker relay for the fast idle solenoid. It is controlled by the ECM which you do not have anymore. And it controls the fast idle solenoid which you probably removed as well (part of the "huge mess" on top of the old 305 block).

The other box, I cannot identify, sorry. The diagram for the CCC engine does not show it so I assume it is part of the body harness. Is it the smaller box in the picture?
I will try to dig up some other diagrams for your car but I cannot promise anything at this point. I would recommend keeping the relay unless you are absolutely sure you don't need it.

Regards
Lou

Sidethumper

iTrader: (1)

Thanks for all your help Lou. I will keep the smaller one till I find out exactly what it is.