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Post by blacklight on Aug 21, 2009 5:43:24 GMT -5
Hi all! Magnus from sweden here.
I have a Subaru Columbuss (called domingo, sambar and libero on other markets) which I have a quite big issue with. (This microbus and the Trendy use the same type of engine, in my case, a EF10 which is laying down in the back of the vehicle.)
Anyway, I'm experiencing a wall of impossibility when it comes to getting any power, speed or rpm out of it. It's a carburator model. When I press the gaspedal past a certain point (main system taking over from the fast-idle system), the engine just splutters and shuts down and dies. No problems restarting it again, but the problem remains. This happens no matter what weather or engine temperature.
I've checked the following: -Fuelpump: Replaced, OK. -Fuelfilter: Replaced. -Distributor: Replaced with rotor and cap, OK. -Sparkplugs and cords: Replaced, OK. -Ignition coil: Replaced, OK. -Compression: OK. -Carburetor: Replaced, OK. -Ignition timing: Adjusted, OK. -Timing belt position: OK.
Made a specialtool to check the floatlevel, and came to the conclusion that the level drops to the bottom of the floatchamber when I'm putting on a little gas.
Totaly weird... :S
Anyone got any ideas?
Thanks in advance.
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Danimal
Getting my two Justys back together after a Justy hiatus.
Posts: 589
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Post by Danimal on Aug 21, 2009 7:36:04 GMT -5
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Danimal
Getting my two Justys back together after a Justy hiatus.
Posts: 589
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Post by Danimal on Aug 21, 2009 7:41:57 GMT -5
Have you tried bypassing the float chamber all together? I've made it home before by soaking a rag in petrol and putting it above the intake when a fuel pump failed. Let the engine run on fuel vapors straight from the rag, if it works better you'll know the carburetor might still be an issue. USE YOUR COMMON SENSE and DONT BLOW YOURSELF UP! -D
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Post by blacklight on Aug 21, 2009 9:14:20 GMT -5
Hi Danimal! Thanks for a fast reply! I made my specialtool out of a drainplug from an other carburetor and drilled a 5 mm hole in it. I then melt-glued a straw in the hole and attached it to the on-car mounted carburetor and started the engine. The floatlevel were correct during idling but the more I turned the throttle up, the lower the floatlevel dropped, and it seems that the fuelpump, despite it's new, can't keep up. :/ My specialtool: g] The floatchamber cover next to the carb body: The floatlevel where it should be. Above the pin = highest level allowed. Under the pin = Lowest level allowed. I replaced it with a carb from an other just like it, though it was used in a car a while ago. So no, it was not new, but the float seems fine on both the carburetors ("old" and "new"). Yes, the float is plastic, but like I said, it seems fine. Nope. Haven't tried that yet. Gonna try it tomorrow, because of rain now... -.- Again, thanks for the reply.
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Post by jeremydde on Aug 21, 2009 11:58:14 GMT -5
You made no mention of blowing out the fuel lines to clean them. Have you checked inside the fuel tank to see if the fuel sock is clogged? It doesn't matter how good a fuel pump is if there isn't enough fuel feeding it.
Jeremy
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Post by blacklight on Aug 21, 2009 12:38:36 GMT -5
You made no mention of blowing out the fuel lines to clean them. Have you checked inside the fuel tank to see if the fuel sock is clogged? It doesn't matter how good a fuel pump is if there isn't enough fuel feeding it. Jeremy Oh right! S**t, I forgot to write that, sorry... When I installed the fuelpump after it's replacement, I used compressed air and the fuel left in the hoses to clean their insides. I also checked the tank and it seemed fine. I cleaned the little net in the tank in the same manner as the hoses. Reinstalled the tank and tada!.... same s**t... -.- Gonna buy a bigger fuelfilter when I get to town and see if the one fitted now is undersized... Hrm... :/
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Danimal
Getting my two Justys back together after a Justy hiatus.
Posts: 589
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Post by Danimal on Aug 21, 2009 23:58:28 GMT -5
It doesn't matter how good a fuel pump is if there isn't enough fuel feeding it. Word! I can only imagine what the problem could be elsewhere with the engine/electrics but I think we're on the right track with the fuel delivery system. If you can 't get the car to rev up higher then we'll know to track the problem backwards from the carb and yes, maybe even right the way back to the bloody fuel tank! Good luck, keep us posted. -Danimal
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Post by blacklight on Aug 22, 2009 4:35:46 GMT -5
Hey guys! During a pause in the otherwise never-ending raining we've been having here, I went out and tried something. I took a small board and placed it on the gaspedal, so that I can put on some gas remotely. I then laid down on the (very wet!) ground and looked at the fuelfilter, which by the way is on the suction side of the pump. First of all, there is just a very little amount of fuel in there, about the volume of thimble (not sure about that word...), and when I reved up, it didn't fill up! Not even the slightest! So I can confirm that there is a really stubborn airpocket in the fuelfilter, and I have absoulutely no idea of how to get rid of it... :/ I've tightend all the clips along the fuel delivery line, but this doesn't seem to solve it... :/ My theory is that the pump doesn't have the pumpfrequency to pump through the airpocket -> thereby the fuelfilter remains with the airpocket -> the pump just sucks air which isn't enough to push the fuel on the deliveryside up to the carburetor -> continues loop. Sugguestions, anyone? BTW; Thanks for the wonderful help, guys. I really appreciate it. -Magnus
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Post by jintei on Aug 22, 2009 20:30:43 GMT -5
maybe your fuel pump ain't getting good voltage cuz an cable instalation problem, why don't you try to run separate cables just to test?
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Post by blacklight on Aug 23, 2009 4:55:29 GMT -5
maybe your fuel pump ain't getting good voltage cuz an cable instalation problem, why don't you try to run separate cables just to test? Good theory. Tried it at once. Connected a voltage meter to the feeding terminal of the fuelpump harness and started the engine (pump disconnected, since the fuel in the carb is enough to idle it for a while.) The reading was about 12.14 v, and since the minimum operating voltage specified for the pump is "9v or above", it's completely acceptable, if you ask me. Also tried to rev it up, and I let it die, reading the same value until the engine completely stopped. Hey magnus/blacklight, Let's hope we can help you with your problem. Perhaps, in return, you'll teach us something about your Columbuss in due time. Let's look at your observations and see if we can find a theory that fits: -So your engine won't rev above 1200, -you've noted that the carb's bowl won't stay full once engine revs increase above idle, but is fine at idle, -The pump is new, -The filter is new, -You've found that the filter(see thru plastic type?) is on the suction side of pump and failed to remain full during revs. Ideas: -obstruction between fuel pump outlet and carb bowl. i.e: line restriction. Measure pressure difference. -low pump pressure resulting from --low pump supply voltage --obstruction or (air)leak in suction/filter circuit, --worn pump gears(if its gear type pump). Unlikely as pump is new. -obstruction in return line or at regulator(if fitted) The 1.6L and 1.8L carbed engines also have the filter on the suction side. It is likely that your problem is related to fuel supply but we're still not sure of that. Try spraying some fuel or carb cleaner into carb with throttle open and see what happens. The faulty fuel system theory should allow the engine to reach high rpms at startup(when bowl is full) even if only for a few seconds. Please update location under profile and show us pics of your van when you get the chance, stacks Wow... That's an answer of magnitude... Thanks. -So your engine won't rev above 1200, That's right. -you've noted that the carb's bowl won't stay full once engine revs increase above idle, but is fine at idle, That's right, too. -The pump is new, It's from a similar low-milage car just like mine. Should be fine though. -The filter is new, Yes. But I'm not sure about it's size... :/ May be to small. -You've found that the filter(see thru plastic type?) is on the suction side of pump and failed to remain full during revs.(Attaching pic...) It doesn't even fill up on idling... :S With it's construction, it must have been manufactured to be completely soaked in fuel (aka. no airpocket) and mounted vertically, not horizontal, like I have it. Thing is, the air doesn't leave the filter even when I set it vertical temporarily. Thinking it might be defect... Ideas:
-obstruction between fuel pump outlet and carb bowl. i.e: line restriction. Measure pressure difference. Don't have a instrument for that, but I will get one (no hardware store nearby...) -low pump pressure resulting from --low pump supply voltage Checked. OK. --obstruction or (air)leak in suction/filter circuit, Will check again. --worn pump gears(if its gear type pump). Unlikely as pump is new. It's an electronic plunger type. -obstruction in return line or at regulator(if fitted) Cleansed this line with cas and compressed air, so I think it's ok. It is likely that your problem is related to fuel supply but we're still not sure of that. Try spraying some fuel or carb cleaner into carb with throttle open and see what happens. Will try that, thanks. The faulty fuel system theory should allow the engine to reach high rpms at startup(when bowl is full) even if only for a few seconds. Yes, you can imagine so, but it just splutters and dies... :S Sparks fly as they should, so ignition system is green. Please update location under profile and show us pics of your van when you get the chance, Will do. Thanks guys. Really appreciate all the help I can get.
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Post by blacklight on Aug 24, 2009 4:20:58 GMT -5
The faulty fuel system theory should allow the engine to reach high rpms at startup(when bowl is full) even if only for a few seconds. Yes, you can imagine so, but it just splutters and dies... :S Sparks fly as they should, so ignition system is green. Here's where I get confused; If/that the motor wont rev with throttle open and some type of fuel sprayed into carb throat?? stacks Yes. I think that this experiment involves intravenous feeding the engine with fuel directly into the carburetors throat. (Not my idea). As I'm writing this, I'm on a brake. I'm disconnecting fuellines on the suction-side of the pump and hold 'em drowned in a bottle of fuel to see if the engine runs better. I'm doing this to detect airleaks. Thing is, this won't work on the pressure-side of the pump. :/ Have to dismount the fuelpump and put it about 20 cm from the carburetor, connect the hoses and see if the pump can keep up now, If not, this problem is WAY out of my league... :/
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Post by blacklight on Aug 24, 2009 11:47:45 GMT -5
If not, this problem is WAY out of my league... :/ Working around fuel sucks; it stinks and can seriously injure/kill ya. So play safe BL; you still owe us pics of your van someday!! Spraying fuel into carb throat wasn't intended to be complicated. It was just a way of confirming the theory, that untimately the low level in carb was causing RPM limit. Something smells fishy with your symptoms. -Low fuel level in bowl? -Same low RPM even when bowl is full? Perhaps the main jet is missing(although you've changed carbs). That might explain the low bowl and poor performance. I know, its unlikely; just another theory from a different view. stacks Pictures coming. Back to buiss... Today I found something interesting... If i turned the fuelfilter around, it completely filled up with fuel (aka. no air). This didn't solve the problem, however, it's quite curious... :S The fuel-level is fine as long as I don't rev the engine past fast-idle. When the rpm sinks, the floatlevel increases to it's set level in the floatchamber. My last thing to do before I turn it in to the mechanics at Subaru, is to heat-loosen the upper part of the needle valve (the one in the floatchamber cover.) There is a small filter there which i think may be clogged, or worse, collapsed. I'm gonna have to heat the whole floatchamber cover with either propane or a welding torch... :/ Gonna construct a jig to use so that I don't damage the valve. If none of this works tomorrow, I'm calling Subaru to get a time in the workshop. There goes my savings... :/
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Post by blacklight on Aug 24, 2009 16:15:26 GMT -5
[Today I found something interesting... If i turned the fuelfilter around, it completely filled up with fuel (aka. no air). This didn't solve the problem, however, it's quite curious... :S Ah, so that might rule out the pump end of things. Getting the needle valve apart is definately a good idea if you haven't already done so; there could be a restriction in there somewhere. But the carb was already replaced, no?? Why do you need heat to seperate carb bowl? Try an impact driver instead? stacks The carb was replaced by a carb from an other, identical car which have rolled about the same milage. No no no. Not the carb bowl. The needle valve. The bowl, or the floatchamber, is one with the rest of the carb body. Here's a pic: To get the rest of the needle valve out, I need to heat the entire floatchamber cover, then use brute force to get it out. Thing is, I don't know if there's any thread-lock compound on it... :/ / Magnus.
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Deleted
Deleted Member
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Post by Deleted on Aug 24, 2009 21:51:58 GMT -5
Hitachi carbs are like that, the valve seat is always really tight. There is no loctite it just seems like it. Even with my biggest flathead the brass always breaks on me and the slot rounds out, so I just use a large-ish screw exctractor. However, I only do that when I have a rebuild kit with a new seat, because it is hard to get the seat out without damaging it. Subyswamper may have a better technique, but I don't think he has posted for a while, so I am not sure he will see this soon. Heat should help, but off the top of my head I can't remember how the coefficients of expansion compare between aluminum and brass.
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Post by blacklight on Aug 25, 2009 13:19:16 GMT -5
Today's report...
I got a tip from a friend to fill a ½ liter bottle with fuel and drill a hole just big enough for the fuelhose to fit. I used hot melt glue to seal the hose to the hole. I connected the other end of the hose to the delivery nipple on the carb and started the engine. At normal running it went fine, but trying to rev it, it died. No change there. Started the engine again, I tried to squeeze the bottle to gain pressure feeding into the carb. The engine reved a little higher this time, still, the problem remains.
The problem symptoms now points more to a faulty installed cambelt. This may be because it HAS happend that the manufacturer places the install guide (in our case, the little hole on the cambelt driven pulley) in a manner that makes it hard to decide on which side of the cog it should be. I'm gonna disassemble the cambelt cover tomorrow and see what I can see.
Ps. No, I haven't looked at the floatchamber cover today, or tried to get the d***n valve seat out.
Thanks for every theory you can come up with. Every piece to the puzzle helps.
/Magnus.
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Danimal
Getting my two Justys back together after a Justy hiatus.
Posts: 589
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Post by Danimal on Aug 25, 2009 17:11:00 GMT -5
Are you are sure the problem isn't in a the carb? That's why my method puts the fuel right into the combustion chamber as a vapour off the rag without using the carburettor to vapourise the petrol. The two litre sounds a little more involved than my petrol-rag method but p'rhaps it worked nonetheless. Try getting the camshaft belt right and hopefully it will work; I've got my fingers crossed that we can stop worrying about fuel all together. Keep up the great work! -Danimal
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Post by blacklight on Aug 26, 2009 10:20:25 GMT -5
Thanks Danimal. Tried that soaked-rag thing today. It worked a little better, but not good enough. It has been raining here today, so I haven't been able to check the cam position yet. However, I've begun inspecting and going through an other engine which I have indoors. Checked piston #3 today. Good to have an engine laying around if the need arise. /Magnus
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Post by blacklight on Aug 26, 2009 13:28:44 GMT -5
If the engine still won't rev with plenty fuel then perhaps the original low fuel level theory is false Tell us blacklight, how did the failure occur? Did it happen all of a sudden, or did you notice after fixing or replacing something? Perhaps you received engine as so? stacks It does rev with plenty fuel, but I can't regulate how much it should get. :/ Ever since I installed the engine a year ago, it have had this little effect-glitch at about 20-30% throttle. Earlier it was just to press the throttle past this glitch and the engine would rev fine. Now that's in the past and the engine is acting strange. It came pretty sudden. About 2 weeks after that I adjusted the valve clearance and adjusted the cambelt tension. /Magnus
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Danimal
Getting my two Justys back together after a Justy hiatus.
Posts: 589
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Post by Danimal on Aug 26, 2009 16:39:33 GMT -5
It came pretty sudden. About 2 weeks after that I adjusted the valve clearance and adjusted the cambelt tension. P'rhaps the valves need checking again; two weeks sounds like too long(how often I drive) for the valves to suddenly lose their setting after having been adjusted but maybe a check could help. What specifications did you use? I've read measurements on this site too specific for my set of feeler gauges. The measurements are on a sticker on the under side of my bonnet and although I don't have feelers at those exact measurements mine are within the allowed variance. Just turn the engine over plenty and be sure to get them all the same. Why did you adjust the camshaft belt tension? Is it now more loose on the side without the tensioner? I think you've got to be sure the timing is correct before going any further. Maybe you did everything right and that two weeks later is when the carburettor began to fail. I'm sure that you'll let us know what you find next. -Danimal
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Post by blacklight on Aug 27, 2009 3:02:48 GMT -5
Stacks: Indeed. Danimal: I will check 'em again. They're supposed to be at: Intake: 0,13 - 0,17 mm and exhaust 0,23 - 0,27 mm. I'm using the values stated in the workshop repair manual. I adjusted the tension of the cambelt because the tension on the long side (the one without the tensioner) was so loose I coult put a shiney penny on it and it would move almost 5 mm. In other words, is was WAY to loose. The timing will change as I adjust anything with the cam drive (move camshaft, adjust tension on belt etc.). The flow goes like this: Adjust anything that has to do anything with the cam (allways fully loosen the valverocker screws when doing this.) Adjust the valveclearence. Adjust ignition timing. I sure will. Gonna defy the never-ending rain and check the cam position and hope that it solves the problem. Thanks. /Magnus.
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