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Post by brokebacksubie on Jan 8, 2011 1:11:07 GMT -5
you might try lookin at the exhaust where the two come together the guts of mine fell apart and cloged the exhaust could not get over 3000 rpm s
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Post by blacklight on Dec 15, 2011 12:31:04 GMT -5
Hello everyone! Decided to resurrect my old thread from a long rest. My problem remains, guys.... BUT! I've been looking in some Swedish forums and have found that this problem isn't just related to my car. Good or bad news? It's good, cause it means it isn't just my car, and that someone finds a solution to the problem and posts it so that others can fix it too. It's bad cause it must be a manufactural error with either the whole series or just a batch of engines. Whatever the case may be, it's a problem that bothers many. This is a summary of what I've done so far. Engine mechanical -Checked cam-to-crank position. -Checked valve rocker clearance. -Checked compression. -Checked engine vacuum. Note: The vacuum is jumping at idle about 55 kPa (16-17 inHg, 400mm Hg). -Checked ignition timing. Note: The timing can be adjusted so that the idle vacuum is fine, but then the ignition timing is off the scale. This doesn't seem to solve the problem either. Fuel system. -Checked fuel tank recirculation system. -Checked fuel pump performance. -Checked/changed fuel filter. -Checked all fuel lines and checked inside of fuel tank. -Checked carburetor needle valve and it's little filter. -Checked carburetor cover gasket. -Checked/cleaned carburetor jets and air bleeds. -Checked carburetor-to-manifold gasket. -Checked idle valve solenoid. Note. A small leakage were detected here. Changed the solenoid - no leak. Other points -Checked all vacuum hoses for proper connection and condition. -Checked EGR-valve for proper function. -Checked the oilseparator in the rocker cover. Not sure if there's supposed to be a valve here though. Ideas? Thinking the exhaust-ports may be clogged, as this would explain low vacuum despite good compression, as the exhaust gases can't get out properly. Oh. And I never re-tightened the cylinder head bolts when assembling the engine. What may this cause? The car doesn't consume unnaturally much oil, and no coolant disappears. Sincerely, Magnus.
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on Jan 1, 2012 4:51:15 GMT -5
are you saying your idle vac is jumping by 16 in? or is at 16 in? if its jumping at idle, you have a sticky valve, or a valve seat thats bad. low (16") vac but stable is a sign of bad cam timing, low by 2" or so is ignition late timing. (normal idle should be 20-25" www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm this site gives you good info and pictures. One of the least used, but best friends a mechanic can have....a vacuum gauge.
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Post by blacklight on Jan 6, 2012 8:46:07 GMT -5
Hello. Last time I checked, idle vacuum was bouncing just a little between 16 and 17. I do have a vacuum gauge, so just tell me what readings you want (during what conditions and so on). Thing is, I can't set the vacuum right without having the ignition timing off the scale, and I can't set the ignition timing right without having the vacuum off normal readings. :/ Oh, and I've now checked the EGR and it's solenoid valve for proper function. Thinking I shoud try to install some old plugwires, since the one's I have now is home made by using sparkplug wires and some caps that I brought at a low-price chain of hardware stores here in sweden. //Magnus.
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on Jan 8, 2012 3:49:24 GMT -5
sounds like 1 of 3, maybe 4 things it could be. can you tell me the vac reading at correct timing of 5 degrees with the vacuum line disconnected from the distributor and plugged so that not sucking air (stick a bolt in it). you should have about 18-20" maybe 22" if lucky. This will also depend on which point you connect the gauge at, DO NOT use the vac line to the distributor as these can be shut off at idle so ignition stays retarded at idle.) Pick a point on the manifold side of the carb butterflys to connect into, i use the vac line to the enrichment valve, its all donearound idle so thats not needed for testing (thats the line that goes to the regulator unit mounted by the right hand suspnsion tower. if its higher than that then thats not a problem, just indicates good suction. Don't worry about the reading on the gauge, its all relative, its what the needle does thats the big thing, there is no figure to set the car to, mine sits at 18- 19 inches on the justy, but only at 11 on the big V8 due to the cam overlap.
with timing at 5 degrees btdc, idle set about 800 ish (where it ticks over nicely) look at the gauge and then watch it for a minute and note what it does, what i'm looking for is a stable reading that may vary by about 2" over all, quietly rising and falling in time with the revs. at this point, retard the timing to 0 degrees and the needle should drop by about 2 inches, if it does, then timing is ok. rough guide is set timing on warm engine to highest vacuum, then back off until pre-ignition under load (aka, "pinking" if any, unlikely, as i don't notice any even at crazy timing of 25 degrees) stops. you might find 8 degrees suits your engine better, mine likes about 7 to give good pickup and stable idle.
if its doing anything else, note what its doing ie unstable revs, slow rise and fall on gauge, steady then suddenly dips etc, and the readings and let me know. If you rev the car and let it come back to an idle, needle should drop as you open the throttle, then climb above normal as you close throttle then settle at normal point.
if its running on 3 cylinders, forget the leads for the moment, if its missing or playing up, then change them, certainly won't hurt. You need to have engine at operating temp, choke off, air cleaner fitted, valve clearance set correctly (0.010" (0.25 mm) exhaust, 0.006" for the inlets, i guess you will know that you set them using those other single lines on the crank pulley right? very easy to get them wrong and man, does it make the car run funny) and correct fuel level in carb (wee dot in float window, fuel should be level with dot, or about 1/2 way up widow at idle.
make sure exhaust isn't blocked. hesitation or "stutter" when accelerating can be due to ditributor cap, plugs, leads, or more likely, low float level, 1 mm can make a big difference.
let me know what you find.
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Post by blacklight on Jan 13, 2012 12:11:45 GMT -5
Hi all. I've now installed a carburettor that I've rebuilt. It has a small window on the side of the float chamber, that makes it possible to check the float level whilst the engine is running without having a special tool. The float level is where it should be... Though, this proves that the problem isn't the accelerating pump, nor the rest of the carb, since I made a new gasket for it as well. If the weather is good, I may make my way into the cambelt to check there (AGAIN!). Also; I will check the reed-valve that I've found in the valve rocker cover. Dogoman: A lot of text there. I think I understand it all, but could you re-write it into a step-by-step (1 2 3) guide? Just to rule out any misunderstandings between translation and actual action on the engine. Sincerely, Magnus.
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on Jan 14, 2012 1:54:30 GMT -5
ok, no worries, i'll also type it slowly in case you can't read fast hehehe
first, confirm correct cam belt timing, crank key vertical at top, hole in cam pulley in line with mark on cover, check correct float level and correct valve clearances (0.006" inlet, 0.010" exhaust)
then...
step 1, set timing at 5 degrees using a timing light on the crank pulley, NOT the timing marks on the flywheel, and confirm that when you rev the engine, the timing advances towards the 15 degree mark, or even further. If the marks do not advance, distributor advance is faulty, and you are not likely to get much power out of the engine. correct this then go to step 2.
step 2, connect vacuum gauge to a point on the manifold so its between the carburettor butterfly and engine.
step 3, start engine and note reading, not worried what the reading is, just note it down for reference. It should remain stable within 2" Hg at idle
step 4, retard timing (turn distributor and use a timing light) with engine running to 0 degrees, reading on vacuum gauge should drop by approx 2" if it does, then ignition and cam timing is ok, reset timing to 5 degrees and road test.
As a further check after step 4, If you rev the car and let it come back to an idle, needle on vacuum gauge should drop pretty close to zero as you open the throttle quickly, then climb above normal as you close throttle then settle at normal point you saw in step 3
if its doing anything else, can you write down exactly what its doing please
That is, do you have unstable revs ?, slow rise and fall on vacuum gauge?, steady reading then it suddenly drops and returns to normal? needle not steady? if its not steady, what range is it over (low and high readings when its oscillating) etc, and the readings if they are not as I have described in the steps above and let me know.
hope this makes sense
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on Jan 14, 2012 2:04:31 GMT -5
oh, just had another thought, what weather conditions does this occur in? cold?, hot?, wet? does the engine rev freely when not driving, or is this problem there all the time or only when on the road?
if its in the cold, do you have the warm air inlet getting air off the exhaust manifold? or is it getting air from the main inlet?
i'm wondering if its icing the manifold or carburetor due to cold air.
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Post by blacklight on Jan 31, 2012 16:35:35 GMT -5
Hi all. Made a video of the test that dogoman said I should conduct. May have missed something though. Here's the video: www.youtube.com/watch?v=7U3MCgI2KnEOh, and for dogomans questions: It's doing this regardless of outside temperature in any relation to engine temperature or vice versa. Also, this problem appears both with the engine stationary or at the road.
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on Feb 1, 2012 0:34:13 GMT -5
well done, the vid helps a lot. I suspect you do not have any advance on the distributor,it certainly sounded good with plenty of manual advance mine screams its head off with the 15 degree mark just visible behind the alternator belt, but doesn't like driving with that much advance...and I'm wondering if maybe you have a timing issue on the cam as well. 1 Tooth at the cam will make all the difference. subarujusty.proboards.com/index.cgi?board=everything&action=display&thread=4432 check this link and see my thoughts later in this post. Vacuums look about exactly what i'd expect to see at 0 BTDC, would have been nice to see the difference at 5 BTDC for comparison, but anyway, they are ok, nothing stupid that I can see from what you have done. next job, prove advance is working. timing light, ignition set at 5 degrees, engine running. vac line off distributor and plugged, apply revs... watch timing marks, they should advance to approx 10 degree mark at about 3000 rpms, (i.e. initial timing plus 5 degrees or more) if you quickly snap rev the engine, (blip the throttle quickly open then shut) the timing marks shoud advance, then retard smoothly, if they are jerky, then you need to strip and clean the distributor, this is the "centrifugal" advance done by weights to get advance on before manifild vac rises. now, reconnect the vac line to the distributor and repeat test, advance should go a lot further (vac plus centrifugal = lots of degrees, about 15 or so from memory) if it does, then advance is ok, if not, its either a faulty diaphragm, or stuck advance plate. I'm picking the advance plate is stuck due to old oil and grease seeping up the distributor drive shaft. Strip and clean and LIGHTLY lubricate the distributor and advance plate. No need to remove the shaft, just the points and advance plate, wash, clean and lube, "lightly is rightly" as my tutor used to say. Check diaphragm advance by turning points plate so lever from diaphragm moved 5 mm or so and see of air is expelled / sucked into diaphragm, if its not, then thats faulty. Rubber bits don't like great temperature variations and it may have a pin hole, which will certainly stop it advancing. if thats all ok, try advancing the cam timing, as a lot of people (myself included) find that we end up mid way between teeth when fitting a cam belt with the marks lined up. Remember, as tight as possible on the "long" side of the belt when you fit the belt, you will find the timing retards by up to 3/4 of a tooth at the cam when you do up the tensioner. Remember 1 tooth at the crank is 2 at the cam, you could advance the cam by 1 notch and see what its like. I generally make sure crank is set right, then set cam to closest tooth, tension, turn engine over by hand 2 revolutions and recheck timing, adjust as necessary, I err to the advance if i'm 1/2 way between teeth to allow for retardation as belt gets old. let me know how you get on
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Post by blacklight on Feb 14, 2012 16:50:34 GMT -5
Sorry for long time to repoy, I've been busy looking for jobs. :/ Dogoman: I've had a look inside the distribubutor and I cleaned the huge ballbearing supporting the igniter unit. Also, I've noticed that the bearings on the centrifugal weights is somewhat worn, but Subaru can't get new bearings, and I don't have the material or equipment to manufacture new ones. :/ May be able to get the material for it from a friend that repairs forest processors. Q: Would it work with nylon bearings? Also, the vacuum advance works perfect, so I belive it's something with the centrifugal weights. Gonna try to do a compression test some day soon, and post the results here. //Magnus.
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Post by blacklight on Mar 17, 2012 13:59:24 GMT -5
Ok... Getting really mad with this god d**n problem now.
Quick question: would a justy-distributor (with cap) be possible to mount on my engine? Can someone take some basic photos of the distributor, inside too?
//Magnus
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on Mar 17, 2012 19:20:28 GMT -5
other option is to lock the centrifugal weights in one position and just rely on vac advance only. Its a crude method, but will at least give you a baseline as to whether the weights are affecting things too much. If you do lock them in the "closed" or retarded position (as in closest to the centre shaft, which is their resting position) it would pay to set your base ignition timing at about 10 degrees, and see how it goes from there.
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Post by blacklight on May 1, 2012 12:01:43 GMT -5
Hi all. Sorry for long time to reply. I've manufactured new bearings and support-bolts for the centrifugal weights now, just gonna get them mounted and then see what happens. May upload pictures later. //Magnus.
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Post by blacklight on May 3, 2012 2:46:08 GMT -5
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dogoman
A Boxer engine will fit in a Justy, its called a WRX
Posts: 445
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Post by dogoman on May 3, 2012 3:25:42 GMT -5
well done, nice machining job
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Post by blacklight on May 4, 2012 5:25:29 GMT -5
Dogoman: Thanks. Now I've discovered that Subaru made 2 editions on the dist, and it involves different diameters on the bolts that hold the weights (see pic above to see what I mean.) I now have to move the rotor on the pic to the housing I have on the car. (God knows I want a garage for this... -.- ) I'll be back with more info later. //Magnus.
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Post by blacklight on May 10, 2012 15:23:14 GMT -5
Ok. So now I've changed the rotor to the one I made the bearings for. This proved to be a real mot******ng pain in the a**, since the roller bearing on the rotor shaft is press fitted, and I don't normally have access to a press. Luckily, I asked a local mechanic/store if I could borrow theirs, and I could. After a few minutes of arguing with myself on how to re-fit the bearing in the distributor housing, I managed to get it there in about 20 minutes. After that, it was pretty much a straight forward assembly of the rest of the distributor. I had to repair the gasket between the lid and the housing (old cracked rubber... ) and gonna test-mount the distributor tomorrow. Can't wait. //Magnus.
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Post by blacklight on May 13, 2012 13:34:34 GMT -5
Got the dist mounted now, and got the car started *happyface* Just need to borrow a timing light to set the timing right, and change the pin securing the distributor coupling on the axle. I'll be back with more info later.
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Post by blacklight on May 14, 2012 12:16:56 GMT -5
I've changed the pin now. Just gonna get the timing right, some day this week.
//Magnus.
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