1981 El Camino

Update your progress on your various car projects.

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Maverick
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Re: 1981 El Camino

Post by Maverick »

Fuel pump wasn't leaking. Output fitting needed another turn. :oops: Aviation Permatex held for a while but then gave up. Should be good now.
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Fuel Tank Vent

Post by Maverick »

The first 5 gallons of fuel went into the new tank no problem. The second 5 gallons had to go in VERY slowly, maybe 2 gal/minute. :shock: Turns out the aftermarket tanks are not vented correctly for filling and the 5/16 vent hose I put on to compensate for expansion and usage won't handle the flow for filling.

Lots of years-old threads on this problem on the El Camino forum but it was supposedly fixed in the newer tanks. NOT fixed on this one.

A mod to the tank is required to get adequate fill rate. The fix is to tap into the tank near the top (should be some air space left for expansion) and up high in the filler tube and run a 1/2" hose between the tap ins. If interested, see post #11 in this thread. http://www.elcaminocentral.com/showthread.php?t=34336 He recommends brazing the nipples in but I plan to use an epoxy gas tank repair kit to install the nipples.

These adds to my project will keep me busy for a while. :? Exhaust will be done tomorrow. Don't know if the rust in the floor, the boogered up door window, or the tank vent will be next.
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Maverick
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Re: 1981 El Camino

Post by Maverick »

Well, the exhaust system was installed today, but it's not done. :cry: It has a terrible resonance/drone right at the RPM used most around town, probably about 1500. Too many of the "fixes" have to be re-fixed. :evil: I'll call Donald tomorrow and let him know I'll be back. I expect the fix will be to add glass pack resonators to the tail pipes like was done on the Maverick and Lincoln.

Right now, I'm thinking the carb tuning should be done before the exhaust fix. Could be the the smoothness of the engine will affect the sound significantly.
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Re: 1981 El Camino

Post by Maverick »

Intended to wire up WXO's AFR meter and went looking for a switched 12V source for it. The choke heater wire seemed like a good possibility, IF it's 12V. I know some choke heaters don't use a full 12V. Put the volt meter on it and ... nothing!! Traced the supply wire to what I think is a relay on the firewall behind the distributor.
0518171341.jpg
Checked the wiring diagram and learned that power for the choke heater come thru the oil pressure switch. Maybe this relay is switched by the oil pressure switch? Anyway, maybe there will be power to the choke heater when the engine is running? Went to start the engine and ... "click" ... no crank. :(

Pulled the starter off this afternoon and it runs on the bench. Maybe a flat spot on the armature? Anyway, I called Summit and a replacement is on the way. UPS will pick up the defective starter in a few days. Another example of great customer service at Summit. :D

So, the fuel tank doesn't vent, the $176 Powermaster starter works for just a few cranks, the new exhaust system has a TERRIBLE drone, ... it's hard to feel any progress here. :cry:
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Maverick
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Re: 1981 El Camino

Post by Maverick »

Starter is working. Please don't ask. :oops: :oops: :oops: :oops: :oops:

I deliberately ran the gas down low on the trip to Henry's Muffler so I could pull the tank, drill it and install the vent but I didn't know how low it got. Lucky to make it home. Tried to start it today and its OUT!! :shock: Guess the fuel tank vent gets moved up in priority.
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Maverick
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Re: 1981 El Camino

Post by Maverick »

Got the tank out, drilled, and fittings soldered in.
0528171709.jpg
A 1/2" fuel hose will connect the two fittings to vent the tank while filling.

I used the method Bro Willy recommended to eliminate fumes in the tank before a torch is applied.'
0528171712.jpg
0528171712a.jpg
That's how the Army does it. Worked. I'm still here.

I used a magnet to get most of the chips from the drill out but I know there are some still in there. Hope the filters stop them. :?
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Re: 1981 El Camino

Post by Maverick »

Intended to wire up WXO's AFR meter and went looking for a switched 12V source for it. The choke heater wire seemed like a good possibility, IF it's 12V. I know some choke heaters don't use a full 12V. Put the volt meter on it and ... nothing!! Traced the supply wire to what I think is a relay on the firewall behind the distributor.

0518171341.jpg


Checked the wiring diagram and learned that power for the choke heater comes thru the oil pressure switch. Maybe this relay is switched by the oil pressure switch? Anyway, maybe there will be power to the choke heater when the engine is running?
Yep, the lead from the device behind the distributor is hot only when the engine is running. I think it's a relay switched by the oil pressure switch. So, that lead will also temporarily provide power to WXO's AFR gauge. After a couple of detours, I can get back to wiring it.
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Found it!!

Post by Maverick »

Found the relay. Figure 8A-57, Page 8A-69, 1980 GM Service Manual shows the "Choke Heater Control Relay" for the 231 CI V6 with gauges. Looks like it was only used with the 231 and gauges.
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Basement Paul
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Re: 1981 El Camino

Post by Basement Paul »

I thought everybody knew what that was... :roll: Good find!

-BP
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Maverick
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Re: 1981 El Camino

Post by Maverick »

After the instrument panel was replaced, the speedometer (among other things) didn't work. Figured the end didn't get pushed in all the way. This is what the guys one the El Camino forum say about installing the cable. :cry: http://www.elcaminocentral.com/showthread.php?t=217697

I can reach the cable by removing the cluster bezel, light & wiper switches and their mount, and reaching in. Gave it another push, jacked the rear wheels off the floor and ... speedo not working. Pulled the cable and the end, that should be squared off, is a rat's nest of twisted wire. Was it like that before? Is the speedo head seized? Who knows. New cable is $70. Haven't decided if the cable should be replaced or I should count this as one more strike against the stock instrument cluster.

On another issue, the voltmeter has been reading about 7 volts with the engine running. For a while it read 13 and now back to 7. Found 2 instrument cluster grounds and they both look good. Voltage read across the battery terminals is 13+ with the engine running.
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Re: 1981 El Camino

Post by Maverick »

WXO and I took the El Camino out to see what the AFR gauge could tell us. It was running kinda poorly but not horrible. Idle AFR in the high 12s which I think is OK. Did a medium speed 2nd gear WOT and the AFR meter went dark. So, we did a Uey and went back to WXO house to see what's up. The ill-fitting blade connector for power to the meter fell off. Stuck it back on and in a bit it REALLY started running poorly. Stalled and wouldn't start. No spark even though the 12V+ to the distributor was indeed 12V. SO glad the wire fell off the meter and we had to return or we would have been stranded somewhere other than WXO's driveway.

After 20 minutes or so sitting in the driveway and scratching our heads, it started and ran OK again. Better than before. Drove it home to cogitate for a while. No really good ideas. Coil failing when hot? I made a jumper for the distributor power supply with an extra wire run to a voltmeter installed outside on the windshield. When it acts up again I'll know if the distributor is getting good voltage or not. Added a vacuum gauge just because it was already on the two-gauge mount.

I have to find what's causing the fluctuation to the volt meter in the gauge cluster. Ordered a new AC Delco ignition switch from RockAuto just because it's cheap -- $17 shipped -- and I wanted to take the ignition switch out of the puzzle. The gauge cluster will probably have to come out AGAIN to work some more on the big connector just to ensure everything is making good contact there. I can also test the gauge cluster grounds even though they look good.

On a good note, the fuel tank took gas as fast as I want to pump it with no objections. Vent is working. :mrgreen: And, after a while, the fuel gauge read 1/2 which is about right. One step forward and two back.

Probably should order the $70 speedo cable. :(
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GMJohnny
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Re: 1981 El Camino

Post by GMJohnny »

That stalling issue with no spark sounds like a control module (if you are using a factory GM
distributor). The stupid things would fail all of the time as I recall. They would run cold, but
when they got warm, DOA.

GM
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Re: 1981 El Camino

Post by Maverick »

Thanks, GM. The distributor that came with the engine is an aftermarket HEI. I was thinking defective coil but the module is a good possibility. Maybe I'll pick up a spare and see if it makes a difference.

The thing that leads me away from the hot electronics issues is the fact that it ran poorly when started cold yesterday.

The varying voltage on the voltmeter in the gauge cluster has to be resolved so I'll probably put that one to bed first and see if that affects the engine.
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Dead Again

Post by Maverick »

It quit again this morning with 12V on the distributor power supply. So, the no spark isn't related to the variable in-dash voltmeter readings.

Tried to order this https://msdperformance.com/products/ign ... arts/83647 but I don't think the order completed. No confirmation from PayPal. If there's no PayPal confirmation by tomorrow I'll order it again.

I'm OK with $109 for a hotter MSD replacement module with rev limiting. That'll make it safe to wind it up with no tach to watch. If the MSD module doesn't solve the problem, the original module will be a backup in the car. I'll either take a break for a few days or chase the variable voltage reading till the new module comes.
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Alive Again

Post by Maverick »

I believe the no start issue is solved. The middle (black) wire in the distributor connector wasn't caught properly in the connector. Removed the wire from the connector, bent the tab up, re-inserted the wire, plugged it in and it started. Still rough on idle but it's running. Sounds good when the throttle is cracked.
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