"Akio Ohtori - RIP Oppo" (akioohtori)
03/21/2019 at 10:57 • Filed to: project golf ball
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"Akio Ohtori - RIP Oppo" (akioohtori)
03/21/2019 at 10:57 • Filed to: project golf ball | 3
| 13 |
Weirdly this is the first time I feel like I’ve made progress on this car, even though I didn’t actually make any. But I have data, and I love me some data. Here is how stuff went last night...
For those not following the saga, basically my 86 Wagovan is having... issues. Issue 1 is an apparent fuel starvation issue when at sustained high throttle (long on-ramps, etc). Issue 2 developed after altering the timing, the engine runs rough at idle, with a little bit of a hunting idle, and wants to be way leaner than before. It appears to be running very rich, but the weirdness will come and go.
Issue 1 - Fuel Starvation
In an attempt to address Issue 1, I’ve already changed the fuel filter, fuel pump, fuel lines, fuel 1-way valve, coil, cap, rotor, spark plugs, HT leads wires, and adjusted the valves and carburetor float. Mostly basic tune up stuff and it did make the problem go away... for a time.
I had not, however, checked the fuel pressure and the fuel flow, because I didn’t want to. That was last night’s task.
Long story short (too late), the fuel pressure was pretty much perfect, hovering right around 2.9 psi (spec is 3.0). Pressure with the fuel return capped was well above the minimum of 2.7 psi, running right at 4.1 or so. Fuel flow needed to be a minimum of 5.7 fl oz in 60 seconds and I hit that in 20 seconds.
!!! UNKNOWN CONTENT TYPE !!!
The positive is that I didn’t find anything wrong. The negative is I didn’t find anything wrong.
With that, I don’t really have anything left aside from assuming that Issue 2 and issue 1 are related. Or at the very least I’m not going to continue chasing Issue 1 until Issue 2 is resolved.... probably.
Issue 2 - Wonky Idle
Wouldn’t be a bad band name. Anyway, my strategy here was to just poke at stuff and see what I could see.
I’d developed a theory earlier in the day that I might have a fuel leak into the carb, which would explain the cars sudden dislike of gasoline. Sure enough, when I popped the air cleaner off there was some staining on the gasket, indicating a fuel leak. I could also see evidence in the carb throat that fuel had been leaking. I re-torqued the screws and did not see any further indication of a leak as I proceeded with troubleshooting.
Next up I checked the manifold vacuum as some people had suggested doing. Vacuum looked pretty excellent, holding super steady right at 20 inHg. I did some playing with the idle and mix screws to see if I could get that number up a little, but the best I could get is about 22 inHg. Apparently my tuning by ear is pretty ok.
The biggest takeaway from this was the ignition problem seemed to be intermittent, with the car running fine for a little bit, then like crap, then fine, with no real pattern. Also it seemed to hate fuel. Even a hint of carb cleaner and it would bog down or die. If I opened the throttle very slightly, enough to trigger the accelerator pump but not an appreciable throttle opening, the added fuel would bog the engine way down and make it sound like it was missing.
The fact that this all started when I moved the distributor makes me suspect a wiring or ignition issue. This suspension is strengthened by the problem seemingly getting worse when it manipulate the ignitor wires on the back of the distributor. The wires look OK, but covered in oil and grit. I plan on inspecting them when the replacement parts come in.
As mentioned in my last post, I just found out this thing has a condenser. Not sure what for as it doesn’t have points. The manual was pretty unhelpful, offering these words of wisdom:
NOTE: The radio condenser is intended to reduce ignition noise; however, condenser failure may cause the engine to stop running.
Thanks Honda! >_>
Unplugging the condenser at idle didn’t seem to change anything, which increases my suspicion. Also, poking around on the internet I found this post from !!!error: Indecipherable SUB-paragraph formatting!!! that sounds eerily familiar:
What symptoms point to a bad condenser? My 29, which has a new distributor with modern points, acted up something terrible lat night on a 50 mile run. It started with a random miss at 45 mph, and within 15 miles, we were limping along in first gear, bucking and powerless, with an occasional backfire out the carb.
People had a lot of suggestions, most of which are irrelevant because I don’t have points, but there was a consensus that the condenser could cause those problems.
So... what if my fuel starvation issues aren’t fuel starvation, but actually something in the ignition system getting hot and deciding it is over it? Or maybe I have dirty/ corroded contacts on my ignitor and messing with it while playing with the timing shorted something out?
This small glimmer of hope is almost certainly false hope, but it is all I’ve got so I’m rolling with it.
New parts will be here next week and in the interim I’ve got some plastidipping to do!
Highlander-Datsuns are Forever
> Akio Ohtori - RIP Oppo
03/21/2019 at 11:06 |
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You have replaced the spark plug wires too right? I’ve had similar problems with a fuel injected car and it was a bad wire. When I had a similar problem with a carburated car the timing chain was set 1 tooth off from spec so no matter how much we rotated the distributor it wouldn’t be on. The car ran fine at 1/2 throttle then fell flat at 4,000 rpm or at full throttle.
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Akio Ohtori - RIP Oppo
> Highlander-Datsuns are Forever
03/21/2019 at 11:09 |
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Yup wires were done with everything else (sorry I accidentally used the Britishism “HT Leads”... been watching too much Wheeler Dealers of late ). Funny enough it is fine at high throttle and RPM, so long as I don’t stay at high throttle for very long (~30 seconds is enough to piss it off). Worth double checking them though. I’ll try misting some water over the ignition system at night and see what I can see.
benjrblant
> Akio Ohtori - RIP Oppo
03/21/2019 at 11:12 |
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Nothing valuable to add, but I really appreciate reading these and following your process.
Future Heap Owner
> Akio Ohtori - RIP Oppo
03/21/2019 at 11:36 |
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I’m loving this very extended diagnostics & troubleshooting series. Excellent Oppo. It’s been doubly interesting for me because I’ve never had or worked on a carbureted vehicle. Here’s to hoping it’s the condensor!
AuthiCooper1300
> Akio Ohtori - RIP Oppo
03/21/2019 at 11:38 |
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Once I had a car whose engine would just... die, suddenly and without warning. I replaced everything (carb, coil, distributor, leads - the lot); my mechanic, who knows these engines inside out, did the same - and went even further, fitting an old-style distributor (my car had electronic ignition). It kept doing it, no matter what.
Finally I parked the car at my father’s place and left it there for a couple of years, absolutely fed up. One day I decided to take it back home... and it worked perfectly. I decided to check if there was anythin g ” different” - and bingo, the rev counter was not working. Opened the bonnet, found the rev counter wire loose, reconnected it. Five kilometres later the car died again, exactly as before.
I don’t know exactly why a wonky tachometer can affect the ignition, and your car doesn’t die completely, as mine did, but... what about disconnecting the rev counter, just on the off-chance it is part of the problem?
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Akio Ohtori - RIP Oppo
> AuthiCooper1300
03/21/2019 at 11:51 |
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Oh I like this idea! The tach doesn’t always match what my ear is hearing and this would be a simple test. Also the tach (labeled with the 3) is directly connected to the ignitor....
HammerheadFistpunch
> Akio Ohtori - RIP Oppo
03/21/2019 at 12:00 |
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9 times out of 10 when I have an intermittent rough running condition its wiring and its usually moisture in the dizzy or moisture in an exposed wire someplace.
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AuthiCooper1300
> Akio Ohtori - RIP Oppo
03/21/2019 at 12:08 |
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Another reason for cars to suddenly die, without warning, is failure to get current to the positive feed to the coil through the ignition/steering lock switch. If the contacts for the
O
N
position are dirty, burnt or corroded, it may cause the engine to suddenly die
(
or work intermittently, if there is some sort of
–
n
o
n
-
constant
–
contact.)
To test it you have to hot-wire the coil (positive side) with a direct feed from the battery.
T h i s i s a common malady of Alfa Romeos, I might add . A n d because the full starting current goes through that switch – no relay! – this bad contact problem is even more prevalent in the START position .
TheRealBicycleBuck
> Akio Ohtori - RIP Oppo
03/21/2019 at 14:37 |
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Check the ground.
Short version of long story:
Friend’s boss does frame-off restoration of Jeep.
Boss can’t get Jeep to run. It will try to start, but not run.
Boss hires new guy to make Jeep run.
Two weeks later, still no running Jeep.
Boss sells Jeep to friend on a Friday, dirt cheap.
Friend trailers it home, does some testing, discovers they forgot to clean paint off the ground before connecting it.
Friend makes new ground wire.
Friend drives Jeep to work Monday.
Friend quits job to get Boss to stop harassing him about the Jeep.
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Akio Ohtori - RIP Oppo
> TheRealBicycleBuck
03/21/2019 at 14:44 |
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You’d think, as the owner of an Alfa and a Saab, both famous for grounding issues , I would have checked that sooner. On the list, thanks!
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Akio Ohtori - RIP Oppo
> AuthiCooper1300
03/21/2019 at 16:34 |
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Yeah the latter is certainly a problem my Alfa has. It’ll start to crank and then just... stop. Or decide not to crank when I also have the brake lights on. Or when it is in a mood. In all cases you just try again and it starts right up. Probably should add a relay.
MM54
> Akio Ohtori - RIP Oppo
03/21/2019 at 19:53 |
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I’d get on that condenser. I once pushed an MGB half a mile because of a bad condenser...
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Akio Ohtori - RIP Oppo
> MM54
03/21/2019 at 21:46 |
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Man... I really thought that was going to be it
