Jump to content
Ultimate Subaru Message Board

After Rebuild, Cant Keep it Running or to Idle


Recommended Posts

Just out of curiosity, how did you determine a misfire on cylinder 3 ?

I can hear the cylinder clicking on number three. Also, when I remove the spark plug wire on the number three cylinder for some reason the clicking goes away however it runs a lot more rough. But that tells me that my problem is on cylinder number three. It's almost like his firing but not all the way, like maybe not enough you'll is getting to it.

Link to comment
Share on other sites

Probably the carb since you replaced pretty much the entire ignition system is there fuel coming through the line and even if the screws are set right doesn't mean the jets aren't clogged think of a stuffy nose even when you pick the smallest bugge it can make you breathe allot better

Link to comment
Share on other sites

Probably the carb since you replaced pretty much the entire ignition system is there fuel coming through the line and even if the screws are set right doesn't mean the jets aren't clogged think of a stuffy nose even when you pick the smallest bugger it can make you breathe allot better

Edited by pbilt
Link to comment
Share on other sites

Can you spin the push rods while the valve is closed sorry I'm guessing here I'm going back to my vw days its been almost 20 years since I had a ea81 what did you do to it during the reseal rebuild how deep did you go head gaskets rings ?? Because you say the clicking goes away when you pull the plug wire it would make sense that noise is ether spark jump or external loss of compression ether a valve or a bad gasket

Link to comment
Share on other sites

Can you spin the push rods while the valve is closed sorry I'm guessing here I'm going back to my vw days its been almost 20 years since I had a ea81 what did you do to it during the reseal rebuild how deep did you go head gaskets rings ?? Because you say the clicking goes away when you pull the plug wire it would make sense that noise is ether spark jump or external loss of compression ether a valve or a bad gasket

I replaced head gaskets, intake manifold gasket's, I rebuilt the carburetor, I got new pushrods, a new rocker arm for that side, but I didn't touch the rings or the pistons other than cleaning the top of the piston.

Link to comment
Share on other sites

Probably the carb since you replaced pretty much the entire ignition system is there fuel coming through the line and even if the screws are set right doesn't mean the jets aren't clogged think of a stuffy nose even when you pick the smallest bugge it can make you breathe allot better

What would make the carburetor only give fuel to three of the pistons though? I am going to try cleaning the carb again today, and I'm going to try taking off the intake manifold and making sure there are no obstructions that are blocking the fuel flow.

Link to comment
Share on other sites

Have you done a compression test or a leak down test if the cylinder holds pressure and releases pressure as you turn the crank I would say valves are good the tick might be a wrist pin or a rod bearing as far as we know if the ticking stops when you pull the plugs that sounds like piston slap to me do a leak down test

Edited by pbilt
Link to comment
Share on other sites

based on what you sead im still thinking a valve is not closing maybe one of the pushrods is the wrong size or the valves arent adjusted right or a bad hydrolic lifter maybe spinning the push rod while the valve is closed is a quick easy test to see if the valves are close enuff to run ive been stumped before only to have some one else glance at it for a second and say theres the problem maybe a fresh set of eyes would help

Link to comment
Share on other sites

Do a leak down test take the plug out get a hand pump with a gauge and pump some air in there and see if it holds air you can rent the tool from any auto parts store for free if it holds air turn the crank with a bar and see if air comes out the carb or throttle body on the intake stroke and do it again and see if it goes out the exhaust on the exhaust stroke and see if it holds air on the compression stroke

Edited by pbilt
Link to comment
Share on other sites

Did a compression test today. Tester read it was running at about 149 on the Bad cylinder. Which at an altitude of 5000 feet, I think that is pretty good compression. So here's what I'm thinking… I think that while I was putting the intake manifold back on, or the carburetor back on, I might have left either a piece of rag or maybe a nut or bolt somewhere that is now keeping the fuel flow from getting to the cylinder. This is really my only other option, since Spark is OK and fuel seems to be flowing well. What I plan on doing is taking off the intake manifold and and blowing down it with compressed air, as well as sucking out with a shop vac. Just to be sure I did not miss anything I will reach down with a magnet head and see if I can retrieve any missing bolts or not. If this fails, I will be taking the car to our local superspecialist and hoping that he can find the problem. Also, it could be possible that when I cut the carburetor gaskets, I did not cut them correctly and maybe they're partially blocking the fuel flow. I don't think this is the problem but it could be.

Link to comment
Share on other sites

Don't pull your intake yet ... I don't think you would leave anything in your intake - You know better than that.

First try unplugging the coil.  Then turn over several times with key.   Pull plugs to see if they are all wet with fuel.  All cyl have fuel?  Good.

Next, run the car in total darkness, hood open, and look for spark jump at the plugs... Maybe swap #1 and #3 wires.   Could have a cracked insulator on your spark plug - Inspect closely.

  Check your disty cap for cracks and clean up the contacts.   If you have a spare cap, try that.

  Make sure firing order is 1 3 2 4 counterclockwise.   Ohm out your plug wires to check resistance.

  The ticking could be an exhaust leak from below - check at exhaust to head while lying under the car.

  Check for vacuum leaks with carb cleaner spray - see if idle changes.

Link to comment
Share on other sites

what was the compresion on the other cylinders any back fireing are you sure you using the right timing marks its posable your plug is fireing while the valve is still open the timing light only gives you # 1 timing or what ever cylinder its hooked to recheck top dead center and confirm you rotor is pointing to the #1 spark plug wire then rework your wires to match your fireing order dosent hurt to double check the simple stuff its always the simple little stuff that gets me

Link to comment
Share on other sites

Don't pull your intake yet ... I don't think you would leave anything in your intake - You know better than that.

First try unplugging the coil.  Then turn over several times with key.   Pull plugs to see if they are all wet with fuel.  All cyl have fuel?  Good.

Next, run the car in total darkness, hood open, and look for spark jump at the plugs... Maybe swap #1 and #3 wires.   Could have a cracked insulator on your spark plug - Inspect closely.

  Check your disty cap for cracks and clean up the contacts.   If you have a spare cap, try that.

  Make sure firing order is 1 3 2 4 counterclockwise.   Ohm out your plug wires to check resistance.

  The ticking could be an exhaust leak from below - check at exhaust to head while lying under the car.

  Check for vacuum leaks with carb cleaner spray - see if idle changes.

  

of all these, my left field throw to home plate ...  7% likely a cracked insulator on spark plug.  Ceramic is somewhat fragil.

I know that I know better, but I am capable of some pretty stupid stuff, and like I said I have checked everything else. All of this I have done except for the vacuum leak check, and the spark jump test, and wet fuel test. I have tried several different spark plugs, all NGK, and all of them are firing and working as they should. The cap and rotor are new and clean, and I have tried swapping them out with my old one and it does nothing. I rechecked the firing order literally a 100 times. I bought and installed a brand-new set of NGK wires and ohms tested all of them and they're all good to go.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...