Pop-Offs aren't fool proof!

Westy · 04-12-2005, 10:34 AM

Well, not only did the pop-off valve blow to pieces, I cracked the airbox. I have no idea how or why this happened, but it did. Ahhh, the money pit has claimed yet another.

Anyone got an airbox for an 81 SC?. Anyone, anyone, anyone?

vash · vash's Garage

schit!

i will call partsheaven and see what is up.

ubiquity0 · 04-12-2005, 10:42 AM

Weren't you having WUR problems? Did a backfire occur because of a bad WUR, or was a cracked airbox causing the symptoms that led you to think the WUR was bad when really it wasn't?

Westy · 04-12-2005, 10:45 AM

I replaced the WUR, then the box cracked. Schitt, I don't know. I had the car sold, and obviously that sale has been terminated. The thing ran fine, it just needed a WUR. I know its mad at me for selling it. My SC is possessed.

vash · vash's Garage

brian, PH has some clean used ones for $150. let me know if you want me to drop by and get one for you.

ubiquity0 · 04-12-2005, 10:45 AM

The pop-off wasn't epoxied shut was it??

Westy · 04-12-2005, 10:47 AM

You never stopp helping us, do you Cliff? That's 300 bucks cheaper than a new one. Yeah, when you get a chance grab one. I'll come down and wax your car, cut your lawn, and maybe do the windows.

Westy · 04-12-2005, 10:48 AM

No, the pop off was working fine. It['s been in there for a couple of years. Owa Tagoo Siam. I surrender

vash · vash's Garage

ok, i will call PH and reserve one.

cbeers · 04-12-2005, 12:02 PM

Hey Cliff,

Can you stop by Safeway for me too? I am getting hungry!

-Chris

Westy · 04-12-2005, 12:07 PM

OOOH yeah, Safeway makes good sandwiches. And Cliff, while your getting me the airbox, get a pop-off valve and put it in. Make sure you use the correct epoxy. You know how much faith I have in pop-off valves!!

MichiganMat · MichiganMat's Garage

Make sure you lubricate the rubber seal in there while you're at it. My car backfired and it popped the valve clean out of the hole where it was mounted! The rubber in the valve had been sitting in the heat of the box without being lubed and had bonded to itself. I put some lithium grease on it to keep it from happening again.

MobileWrks · 04-12-2005, 02:53 PM

here is what i was thinking. the dist head, either got stuck open,dumping raw fuel in the cyl. then on exceleration causing a back fire, or the pin in the head was stuck,once he punched the gas, no fuel was delivered to the engine causing it to be way too lean ***small mixtures problem wont cause that much damage***.... Any one disagree, going once, going twice......

MobileWrks · 04-12-2005, 03:23 PM

Fuel distributor- Control center, contains a regulator to keep system pressure constant. The main moving part is a central pin which is controlled by the air sensor plate. ** When the throttle is opened the increase of air into the manifold causes the air sensor plate rises and pushes the control pin into the FD which allows fuel out to the injectors. ** Mixture adjustment is via the 3 mm allen screw, turning the screw clockwise makes the mixture richer, remember lean "out".

vash · vash's Garage

ok, "SPECIAL SAUCE" on the sandwiches. extra for brian.

i blew my pop off valve once, just because the mix was off. to take out an airbox with popoff valve, would be one big mutha effa. so you are saying the airsensor plate was off center, causing the FD plunger to stick one way or the other? i think that could be easily determined by doing that magnet on the sensor plate thing. see if it moves smoothly.

MichiganMat · MichiganMat's Garage

im tellin' ya, the rubber seals in those valves bond together like glue...

MobileWrks · 04-12-2005, 06:03 PM

I did a car once and the sensor plate felt fine. Then i pulled off the fuel head and found scaring on the pin. Scuffed it smooth and then ran like a champ.....MM his pop off valve was fine. Pump hold pressures were on the low side but in spec. Set WAR pressures-controled (minor adjustment needed) Set timing. was advance by 6 degree to much. Sensor plate was dirty, cleaned up and was in the correct position. Hold pressures with not controled, did not hold pressures in spec. Prior to WAR installation, his car was running WAY TOO rich, plugs were black, aswell as splutter low to mid rpm. He said it ran fine until they went to smogged it. Dont know why it would happen a few days later after installing and setting all pressures......

cantdrv55 · 04-12-2005, 09:08 PM

Brian,

If you can't make it to Cliff's, PH can ship via UPS or I can get it from Cliff and bring it to Sac. I'll be at UC Davis Med Ctr on Tuesday.

Chris

Westy · 04-13-2005, 06:07 AM

Thanx Chris. I don't guess there's any hurry. The next two weekends are spoken for, and this job requires a motor drop, so I'm just not all that jazzed about jumping in and doing it. Besides, I'll probably replace some seals and o-rings while the motor is out, so it's not coming out in the morning and going back in in the afternoon. Da bi*ch will be apart for a while.