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1981 coupe project almost driving

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Old Dec 21, 2022 | 08:07 PM
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Originally Posted by dlwilson
Thanks for the input! Why two relays? The radiator manufacturer says that one relay is enough for two 12" fans, and supplies one relay with the radiator. (They call for two relays for two 16" fans.) And why two temp sensors? Do you use one per fan?

As far as the hose and filter, that replaces the glass filter that was there when I got the car. The hose is new high pressure (I forget how much) injection hose that will handle the 50 psi going to the fuel pressure regulator. I wasn't able to reuse the stock metal line when I removed the mechanical fuel pump (which didn't work with the Vortec engine). Is there a danger from the hose? I suppose I could replace the filter with a metal one, and the hose with braided line.
In my setup, the fans draw a lot of current. 12 to 14 Amps each just spinning while the car is not moving. The startup current is even higher, which is one reason folks sometimes use a PWM fan controller. At any rate, folks with dual fan setups have reported failures of the single relay, so the second relay is for redundancy. If you are monitoring your gauges, you should be able to make it home on one fan. You will NOT make it home on zero fans in stop-and-go traffic. Of course, in zero traffic, if your car is tuned properly and you are always moving, you don't need any fans at all!

Two temp sensors, or a fan controller, would let the fans come on in sequence. This reduces load on the electrical system. Modern cars do this, at least ones with two fans. It also reduces the single point of failure that my system currently has: If the switch fails, or the connector brakes, I will have zero fans. But I'll hear the silence, even over my headers, and I'll notice the gauge climbing. At least, I hope so.

That plastic fuel filter is a fire hazard. There are much worse things on other cars on this Forum, and you wouldn't believe what came with my car when I bought her, but it is worth mentioning even in this case. There are now nearly a dozen rubber to plastic or rubber to metal joints in your engine compartment. If any one of them fails, you will spray pressurized fuel on a hot engine. If you emailed @lars for his timing papers, email him again and ask for his metal fuel line instructions.
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Old Dec 29, 2022 | 11:42 AM
  #22  
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That makes sense about the fans, and I ordered the Mitsubishi fan PWM fan controller described in another thread here, along with the temp sensor. But for now I just used the single relay so I can get this car driving! I made a simple harness and plugged everything in -- worked the first time! I also got new bleeder screws for the left rear caliper, and was able to easily bleed the brake. The old screws must have been plugged up. I replaced the factory temp sensor in the passenger side of the block with the sensor that came with the radiator. But I still can't drive the car! I cross-threaded the radiator overflow fitting, and stripped the threads on the fitting. The fitting is made of soft aluminum, roughly the same hardness as cheese. So I got a 1/16" NPT tap to clean the threads in the radiator filler neck, and am still waiting on a replacement overflow fitting. Hopefully tomorrow I can drive it. I also have a new eBay special HEI distributor to go in, although the car should drive without it. I also cut out all of the remaining computer controlled carburetor wiring under the hood -- I still need to do a little cleanup on it. I continue to remove paint anything that is bolted down, like hood prop, underhood light, wiper motor, etc. I also wiped down the underside of the hood, not shown in these photos. It cleaned up surprisingly well, and makes things look a lot better. I'll hit it with the pressure washer once I can drive the car out of the garage.





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Old Dec 30, 2022 | 01:36 AM
  #23  
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Originally Posted by dlwilson
The new radiator/shroud/fan combo is in. It bolted in with no extra work at all. And I see the price is down to $219 on Amazon.
link
will the stock air snorkel fit over the rad?
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Old Dec 30, 2022 | 09:15 AM
  #24  
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Originally Posted by calwldlife
link
will the stock air snorkel fit over the rad?
This car did not come with the stock air cleaner, so I can't be sure, but the dimensions of the aluminum radiator seem to be identical to the stock radiator, so I would guess yes. I bought the foam seals for the top of the radiator, but I think I need some more foam to go across the top of the rad. I guess normally the air cleaner would be there? Also I saw that the radiator/shroud/fan setup is down to $209 on eBay.

Also, yesterday I had to move the car off the lift, so I fired it up thinking I would take it out of the garage and around the block. As I started it, I wondered, "how will it fail me this time?". I drove forward about five feet, and the car died and wouldn't restart. Eventually I figured out the fuel pump wasn't running and the float bowls were empty. Later that day I got out the Power Probe and injected 12v+ to the pump and found it still worked. Then I found no 12v battery power to the controller, and finally found a blown fuse for whatever unused computer circuit I used for the pump. That is a really inaccessible fuse panel. I think I popped the fuse when I cut out the computer wiring under the hood without disconnecting the battery. I must have shorted power to ground with the cutters. Hopefully today I'll get a chance to drive it.
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Old Dec 30, 2022 | 11:39 AM
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name brand part number of rad?
thanks
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Old Dec 30, 2022 | 01:19 PM
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Originally Posted by calwldlife
name brand part number of rad?
thanks
These all seem to come from the same factory, as they all look identical.

Here's the exact one I got on Amazon for $219:
Amazon Amazon

Here's what appears to be the same one one eBay without the relay and sensor for $195
https://www.ebay.com/itm/11556308244...BlBMUMLU8MOsYQ
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Old Dec 30, 2022 | 03:06 PM
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Originally Posted by dlwilson
These all seem to come from the same factory, as they all look identical.

Here's the exact one I got on Amazon for $219:
https://www.amazon.com/dp/B097CXX1L3

Here's what appears to be the same one one eBay without the relay and sensor for $195
https://www.ebay.com/itm/11556308244...BlBMUMLU8MOsYQ
thank you my orignal shows a weep is one area.
I need a new rad and worried about proper fit.
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Old Dec 30, 2022 | 08:41 PM
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Originally Posted by dlwilson
These all seem to come from the same factory, as they all look identical.

Here's the exact one I got on Amazon for $219:
https://www.amazon.com/dp/B097CXX1L3

Here's what appears to be the same one one eBay without the relay and sensor for $195
https://www.ebay.com/itm/11556308244...BlBMUMLU8MOsYQ
hey man, I was sorting out the radiator and only review was the rad is 1/2 inch short in height.
I saw where you ordered bigger rubber but ended up using
orig rubber.
would you say the rad is in firmly or do I have to bend the top mounts.
sorry for the questions, too many years of parts made wrong.
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Old Dec 30, 2022 | 09:43 PM
  #29  
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Originally Posted by calwldlife
hey man, I was sorting out the radiator and only review was the rad is 1/2 inch short in height.
I saw where you ordered bigger rubber but ended up using
orig rubber.
would you say the rad is in firmly or do I have to bend the top mounts.
sorry for the questions, too many years of parts made wrong.
I did bend the top mounts slightly to make the fit a little tighter. Yes, the rad is mounted securely. I didn't measure the top or bottom of the radiator tanks before ordering the rubber mounts. I should have gotten 2" instead of 2 5/8".
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Old Dec 30, 2022 | 09:46 PM
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Originally Posted by dlwilson
I did bend the top mounts slightly to make the fit a little tighter. Yes, the rad is mounted securely. I didn't measure the top or bottom of the radiator tanks before ordering the rubber mounts. I should have gotten 2" instead of 2 5/8".
Or, you should have gotten a 2 5/8" radiator.

But if this works, that's great! That whole setup is half the price of just the fans that many of us run.
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Old Dec 30, 2022 | 11:44 PM
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Old Jan 5, 2023 | 09:16 AM
  #32  
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So first, the car is not driving yet. I got the new radiator overflow fitting installed, after running a tap in the the radiator filler neck to clean up the threads, so that's done. And the new distributor is in with no issues. That's all good. Oh wait, I need to find a place to get vacuum to the distributor, but that should be easy.

The car runs with the new distributor, but not for long. The problems are two-fold. First, I put a fuel gauge after the fuel pressure regulator, and it is at 9 psi, even adjusted all the way out. Running the screw in gives 9.5, which is as high as the gauge goes. My carburetor friend explained to me that the regulator can't handle the 50 psi from the in-tank pump I installed. Oh. I guess that's what you get with a $40 regulator. So I can either spend $350ish for a quality regulator (at least I think I can, based on the online specs). Or I can put the carbureted pickup back in the tank, and use an external low-pressure electric pump. That means I'll have to cut into the factory steel fuel line, and run a rubber line from the top of the tank to the pump on the frame rail, and then to the steel line. I was trying to leave this set up ready for fuel injection or an LS swap for a future owner.

I still think I could put a cheap non-return style pressure regulator after the existing return style regulator to try and bring the 9 psi down to 4 psi, but my buddy says that won't work.

Also, the fuel pump is randomly shutting down. This one is probably my fault. I found a random 12+ battery hot wire in the cargo compartment, and used it as power input to the fuel controller. I don't know what's going on with that wire, but since the controller is so close to the battery I'll run a fused wire directly from the battery to the controller. Or I wonder if the fuel pump is shutting down because it's trying to force 50 psi through a 9 psi regulator with a small factory return line (5/16?)?

Anyway, it's really really close to driving. I just hate that I need to pull out my in-tank pump and replace it with an external one. Also I need to call my insurance lady to remind her I need collector insurance on this car, so I can get the car titled and registered so it will be ready for the road when it's driveable.
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Old Jan 5, 2023 | 03:38 PM
  #33  
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Default crisis averted

With some google-fu, I learned that (among others) a 1990 Ford E-150 with a 300ci engine uses a low-pressure in-tank pump that feeds an external high-pressure pump. The low-pressure pump supplies 5-7 psi. I got one from Rock Auto for $21 shipped. It appears to have the same form factor as all other in-tank pumps I've seen, so here's hoping that it's close to a direct replacement for the 50 psi pump that's in the tank now.
I'll fix the wiring while I'm replacing the pump. And then the car will be driving!
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Old Jan 5, 2023 | 03:47 PM
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Originally Posted by dlwilson
With some google-fu, I learned that (among others) a 1990 Ford E-150 with a 300ci engine uses a low-pressure in-tank pump that feeds an external high-pressure pump. The low-pressure pump supplies 5-7 psi. I got one from Rock Auto for $21 shipped. It appears to have the same form factor as all other in-tank pumps I've seen, so here's hoping that it's close to a direct replacement for the 50 psi pump that's in the tank now.
I'll fix the wiring while I'm replacing the pump. And then the car will be driving!
That is very interesting. That, plus a regulator (perhaps), would be a great solution for those of us who want to upgrade in stages, and make a car EFI ready while keeping the carb.
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Old Jan 24, 2023 | 09:25 AM
  #35  
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It's been a while since the last update, but I've been working. And learning about fuel pressure. The low-pressure pump is in the tank and working well, putting out 4.5 psi according to my fuel pressure gauge. Adjusting the fuel pressure regulator does nothing, as the pressure holds steady at 4.5. Emails from Mr. Gasket tell me that the 5/16" return line is the problem, as it gives too much resistance for the pressure regulator work. I'll keep the pressure regulator as it provides easy plumbing for the return line. I haven't replaced the rubber fuel line and plastic fuel filter, but I think it needs to be reworked with braided lines and a metal fuel filter.
I also put in the Chinese distributor. It seems to work fine. I still need to add in a vacuum tee and line for the advance. I got the timing at idle set to about 20 degrees.
I was able to drive the car out of the garage into the yard without it stalling. I think today might be the day I drive to the gas station. I've been trying to get Grundy classic insurance on the car so I can title and register it, but it's been about six weeks, so now I just want to put regular car insurance on it so I can register it and drive it.
Of course, no post about this car would be complete without it letting me down again, so here's a picture of the hood release cable in my hand. Fortunately the side vent grilles are missing from the car, so it's easy to reach up and pull the hood release. New cable arrives today!



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Old Jan 24, 2023 | 01:30 PM
  #36  
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Getting closer!
You will most likely need to retard the timing back down when you hook up the vacuum advance (to manifold vacuum), otherwise you'll have too much advance at light cruise speeds. Knock, knock...
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Old Jan 26, 2023 | 10:40 AM
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So I took it around the block for the second time today. Much easier than the first time, as it only stalled once, right at the start. And I felt the trans shift into 2nd at one point. The vacuum advance isn't hooked up yet, so it wouldn't rev very well, but tubing and tee should be here tomorrow or Saturday. There is also a loud sucking noise when braking, which I'm guessing is the brake booster diaphragm. So that's gotta be changed. Other than that, it drives pretty well, so the previous owner did a good job with bushings/ball joints/tie rod ends/steering ram and control. I still have to:

- replace passenger side window motor
- hook up vacuum advance
- replace hood release cable (how do you thread the new cable into the existing sleeve/housing?)
- a little bit of wiring cleanup under the hood

I have an appointment with the DMV on Monday morning to get it titled and registered, so if all goes well I could be driving it next week. But I doubt it.
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Old Jan 30, 2023 | 11:40 AM
  #38  
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Great news! I'm excited for you. I hope I'm where you are with my 76 in a few months.
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Old Jan 31, 2023 | 10:09 AM
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Default I don't like the DMV

So things did not go well at the tax collector's office. Apparently the VIN on the title is missing the first three characters ("1G1"). The insurance company (Grundy) somehow figured out what the full VIN should be, and put that on the insurance card, and the mismatch put the tax collector ladies into a tizzy. They traced the problem all the way back to 1983, when the incorrect VIN was put on the title. Then they told me it was my problem, and I had to get it verified by the DMV. We finished with me saying, "so I have a Florida title, issued by your agency, and you won't register this car?" "That's correct, sir." They did assure me that the DMV would come verify it at my location.

After a call to the DMV I talked with a person who might be able to come look at it here, if his supervisor approves. Otherwise I'll have to get it towed there and back, or drive it there with no tag, if I get it running that well. Whatever.

On the plus side, I found a big vacuum leak, so the engine is running much better. I also temporarily hooked up the vacuum to the distributor, and I can hear the difference. I just have to find a place to put the tee. And I got the new hood release cable in.

On the minus side, the headlights are now stuck up. I really didn't make any changes in the vacuum system. After some googling I read about the switch under the dash, but that didn't help. I haven't had time to diagnose it, because I've been replacing the passenger window motor. Of course, I didn't read up on it before remove the motor, and now the regulator spring has come unwound because I didn't pin it. I spent quite a while messing with it without success, so I'll watch some videos today and see if I can figure it out. I suspect I'll have to remove the glass.

Then replace the leaky brake booster, and the vacuum system should be tight, and car should theoretically be driveable. But not legally driveable. Ha ha.


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Old Jan 31, 2023 | 10:28 AM
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That's not great news, but it is progress!

Here are some quick Bubba fixes to get you by:
  • Don't put a T in the vacuum line to the distributor vac advance. That should be a straight shot to a MANIFOLD vacuum port.
  • Until you get it sorted, you can cap off most other vacuum ports (keep the brakes, PCV, EVAP, and vac advance!).
  • You can operate the headlights manually until you fix them, or upgrade to electric. Reach up behind under the front bumper.
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