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A simple problem


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that sounds like textbook accelerator pump failure... its a pretty easy fix... however if you're going to replace your accel pump you might aswell rebuild your carb completely...

 

to test if its the accel pump and not some other problem:

 

pop off your air can... then hold your choke open with a screwdriver or something... get a light and shine it down into your carb... now with your other hand turn your throttle... first thing you should see is that arm at the very top of your carb on the front move up on a pivot... and you'll see on the other side of the arm a little rubber boot... you should see that get compressed down... under that little rubber boot is your accel pump... it shoots raw gas into the carb so it doesn't die when you stomp on the throttle... (do all this with the car off... its easier...)

 

now look into your carb with the choke open...(you might need to turn the key to the on position as to get the fuel into the float bowl)

 

pull the throttle open and closed... just keep popping it... you should see gas getting squirted into your carb... if you don't, your accel pump is dead...

 

check that then tell us the results! :)

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Thanx moosens, my garage just didn't seem complete without a subaru (after I sold my RS). and I need to get one of those "Charter Member" icons :banana:here's some shots of the new ride http://forums.nasioc.com/forums/showthread.php?t=974257

 

thanx zefy!!! I'll try that when I get back from Key Largo this weekend, would that be related to not having a vacuum line on the valve on the intake funnel for the airbox? man it's been a long time

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SKIP!!!! how are ya??

 

It's not an April Fools joke :lol: but I can't prove it because this hood isn't getting cut even for a NACA air vent :D

 

I'll be testing the carb tomorrow, but I think it's getting fuel, I saw fuel squirting in from the top, does the throttle need to be wide open? which vacuum hose should I check first? also I noticed the hose coming off the bottom of the airbox is plugged and goes no where, is it important?

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I'll be testing the carb tomorrow, but I think it's getting fuel, I saw fuel squirting in from the top, does the throttle need to be wide open? which vacuum hose should I check first? also I noticed the hose coming off the bottom of the airbox is plugged and goes no where, is it important?

 

wait, are you talking about a little one about 8-10'' long and about the width of a pen? there are two that go on the air box... one wraps around the top of the air box and attaches to the little can on the air funnle doo-dad...

 

the other one is VERY important! it attaches to the intake manifold and without it on you have a MAJOR vacuum leak! it attaches to the manifold on the passenger side... look hard... its right ontop the intake right near a little vacuum can... plugs onto that then into the air can on the bottom...

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An engine running lean will also backfire through the carb.

 

The accel pump issue will cause it to go lean

when you step on it.

 

The best method for the timing is the ping test,

 

advance it till it pings under load then back it off a few deg's.

 

You have looked at and set the point gap -aye?

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  • 2 weeks later...

i'd recommend getting a complete carb rebuild kit... it shouldn't cost more then 50 bucks...

 

you'll get all the gaskets and the accel pump... just make sure you get the carb kit for the right carb... ask for one for the 1600 and they should be able to help you at the parts store...

 

you don't need to use the whole kit... yet its a good idea to rebuild it all anyways... just so you know what you're dealing with...

 

carb cleaner and compressed air is pretty much all you need to do a carb...

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ok, timing on these older Subarus is through the bellhousing. If you look in the top of the bellhousing at the back of the engine, you'll notice a hole which you can see the flywheel through. There's supposed to be a large rubber plug over it but sometimes they get lost. Anyways, hook up a timing light and shine it through the hole. You should be able to see the timing marks on the flywheel. If not, with the engine running, take a Scotch Brite pad or some steel wool and press it up to the flywheel to clean it off. I've also had to go back over the timing marks with a white out pen to be able to see them again. Once you can see them, then you'll be able to set the timing correctly.

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Well, I set the timing to 10 then tried 15, still does it, could it be a binding throttle cable? the pedal and throtte comes back just fine, could it be binding when I push it dowI'll have to catch some video of this, it does seem like it's leaning out when I give it throttle under load

 

you know I should replace the fuel filter, is there only one? or one in the back too?

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Sounds like you've done some of these but for the sake of being thorough;

 

  • Check/adjust timing
  • Set point gap (maybe a good idea to just replace points/condenser because they're consumable and so cheap)
  • Check/set plug gap
  • Be sure coil/plug wires are good by checking with an ohmmeter.
  • Check cap and rotor for excessive carbon buildup and cracks/scratches inside the cap.
  • Check for vacuum leaks (carb base gasket, intake gaskets, all vacuum hoses, brake booster, carbon canister). If you don't have a 'tuned' ear and have trouble hearing any vacuum leaks, you can use a spray bottle filled with water. As the engine idles, spray a mist around all the previously mentioned areas. If there's a leak, the water will be sucked into the engine and the idle will drop/die.
  • Set carb mixture (too lean will miss at idle and backfire when accelerating.)
  • Verify carb secondary is opening.
  • If you've a solid lifter engine (you probably do), you should adjust the valves too. A tight, or burnt, valve will cause backfire. A burnt valve will require the head be removed and the valve repaired/replaced.

Good luck!

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have you checked the anti dieseling solenoid mounted on the side of the carburator? Just a thought sicne you mentioned something about an afterfire when you shut it down. Also, have you tried using some Seafoam through the carb? Might help with whatever might be in there!

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