? re: Sunpro temp. gauge installation

[jaymac]

Regarding sending units, am I going to need an adapter set?
It says it includes a CP7576 sender w/ 1/8" NPT thread. The directions say to obtain the CP7553 or CP 7573 adapters if needed.
The kit has 3 different size adapters w/ it, but they're not labeled or mentioned. Should these be the only things I'll need?
Does anyone know which of these I will need to make it work on my car, and if it can go right in the stock location w/o drilling and tapping?
Lastly, how much coolant should I have to drain to safely remove the sender?
Thanks,
Jeremy

 

[stang8urimport]

I had Sunpro temp and oil pressure gauges in my 83 before doing the customer Autometer dash... The gauges came with everything needed to put it all in. The adapter came with it.

 

[jaymac]

yeah, it appears that the stock fitting uses an 11/16, as does one of the adapters they include, so I think I'm all set there.
Now how about coolant? How much should I need to drain so it doesn't spill when I reove the stock sensor? Or can I swap them w/o draining???
Thanks

 

[stang8urimport]

Nope, it will spill out seeing as where the sensor is a lower point then the top of the radiator. Just empty out enough for the radiator to be below the point of where the sensor goes in. Maybe about 1/4 of the coolant out of the radiator.

 

[jaymac]

how STUPID of me would it be to try to swap the senders w/o draining the coolant (such a PITA if I don't have to).
Just keep a towel in the hole then jam in the new one?!?!
I know, I'm lazy...
No flames please!!!!
If it's a disaster waiting to happen, just tell me....

 

[stang8urimport]

You could. Pull the sender out, and let the coolant come out of the hole until it levels off.

 

[TheUser]

I can't remember if I drained mine or not when I installed my sending unit. I know for sure from a logical perspective (and sorry to say, first hand experience as well), DO NOT REMOVE THE SENDING UNIT UNLESS THE CAR IS COMPLETELY COOLED DOWN!. If you do, the 16lb of pressure in the system will spew 200* coolant all over the place and probably on you too if you don't get out of the way. It scared the hell out of me.

Anyway, you probably don't want any coolant on the threads when you screw in the new unit. Also, I had some ARP thread sealer, so I used some of that to make sure it was sealed off real well (very good stuff, you can get it at most race shops or from summit for about $8-9 - summit also charges about $8 extra for s/h, though).

Basically, you can try it w/o draining any coolant although it's really not THAT big of a deal to just drain some of it. Put a catch pan under the little nozzle valve on the lower pass side of radiator and let about a gallon or so drain out and just pour it back in when done. I usually use a small (probably 3/8") hose over the valve and drain mine into milk jugs, but you could use a catch pan too.

EDIT: Either way you go, you're going to introduce air into the system when you pull the sender, so you'll have to "burp" the system anyway. Once you're done installing the sender and all is well, jack the front of the car up so that the radiator neck is higher than the thermo housing (I jack it up by the drivers side control arm) and let the car run for 10-15 min. Put a catch pan under where the rad. neck is so that any coolant that spills out will be caught. This lets all of the air escape. From experience, I think it's usually best to wait to top it off since the air burps out and pushes what you put in back out - but that usually depends on the circumstances.

 

[HISSIN50]

Yep, you wont lose much coolant if the motor is stone cold. I use a turkey baster (for garage use only) to suck a little more coolant out of the sender hole so that the thread sealer is not diluted as soon as it hits the threads.

Good luck.

 

[88GT17MA]

are sunpro gauges any good? I always thought they were about stock equivalent.

 

[HISSIN50]

The Sunpro's are way way better than stock. the stocker is as accurate as pulling a value out of a hat IMHO.

 

[jaymac]

Actually, it says not to use selaer or tape on the new sender as it will reduce the quality of the ground (on elec. gauges, not mech.) So, I didn't use any, and it doesn't appear to be leaking, but I will watch it. I didn't drain the coolant, and didn't lose much in the swap. I still have to burp it and top it off though/
Either way, the gauge reads accurately right to 180*.
I also have to find and hook into a dimmer wire somewhere, but it was getting too hot and sweaty to keep working on it today

 

[HISSIN50]

Actually, it says not to use selaer or tape on the new sender as it will reduce the quality of the ground (on elec. gauges, not mech.) So, I didn't use any, and it doesn't appear to be leaking, but I will watch it. I didn't drain the coolant, and didn't lose much in the swap. I still have to burp it and top it off though/
Either way, the gauge reads accurately right to 180*.
I also have to find and hook into a dimmer wire somewhere, but it was getting too hot and sweaty to keep working on it today

Yep - that is why I have used an auxillary ground on the sender body (or obviously if a sender is suspended in rubber, like my last install was, then a dedicated ground is needed).

I always have to dope the threads so I just ohm the sender body out, and if the reading is high, run an aux ground (just in case you leak and need to do something about it).

Fuse 13 is the Dimmer/ISO circuit. One can tap right into that fuse (it is downstream of the dimmer rheostat, and the fuse actually receives rheostated amperage). A fuse tap works well on the dead side of the fuse.

I also put a small (1 amp or so) fuse on the new wire running from the dimmer circuit to the new gauge. That way if a short in the new wire develops, hopefully the fuse for the new guage's wire blows before taking out all the gauge lighting. No one else does it though really. IMHO one can never have too many fuses - in normal operation they will never blow. But should an issue arise, it is nice to have circuit protection.

Good luck.

 

[jaymac]

wow, good info!
Now, pardon my electrical ignorance: "dead side" of fuse 13?

 

[stang8urimport]

That's the side fuse box that is NOT hot when it is on. Thus, the fuse cares over the current flow to that side, to the accessory. Thus, the dead side.

 

[jaymac]

hmm...I'm a retrd.
One side of the actual fuse itself or the fuse "box"...
I'm hopeless

 

[HISSIN50]

hmm...I'm a retrd.
One side of the actual fuse itself or the fuse "box"...
I'm hopeless

Not at all. Nick is so happy about his fan that he got carried away and lost me too.

Pull fuse 13. Probe fuse 13's two slots where the fuse 'blades' or prongs go (might need the parking lights on to do this) and one of the two prongs that the fuse goes into will not light the test light. This is the dead side, and it has protection via the fuse.

The side that is still hot with no fuse is the feed and obviously has no fuse protection [from fuse 13]. Very simple - takes longer to describe than do.

Good luck bud.