EA81 Hitachi carb baseline or what is wrong?

[RatCamper]

Don't worry about it, seriously.

These things are so similar to a VW motor it's crazy. Except they don't drop intake valve seats if you look at them sideways.

Does it ever have a condenser! It has two of them! Someone left the old one in place disconnected and used one of the vac advance screws to attach a new one. I can see why though. Looks like a nightmare to get to.

Yeah I'm going to pull the points etc. too. Once I figure out the timing of course. What a disaster that'd be! What grease is preferred for the block on the points on these?

I have to ask, are the Hitachis really that bad? I looked at it and the design looked kind of awkward. Am I looking for an excuse to put the weber on? Yes! But in the mean time I am wondering if the hitachi is scrap.
Working with a motor of unknown history is always a pain. What I found during the lifetime of the motor I pulled out would be enough to put you off your beer and weeties.
The horrors and the expense got too much. I've always liked the EA81 (and what they come from) so it seemed like a good move. I expected teething problems but this motor is being a downright pain.

[El_Freddo]

Have you thought about swapping the intake manifold setups from the old motor (that I presume is dead from compression and not fuelling issues) to this block?

I know this trick works with EA82s unless its an EFI long block as there are differences with the heads and some other little bits on the block itself.

If the last EA81 was setup and running well I don't see why the intake manifold can't be swapped onto this block - unless you've exchanged it for this engine...

Cheers

Bennie

[RatCamper]

Have you thought about swapping the intake manifold setups from the old motor (that I presume is dead from compression and not fuelling issues) to this block?

I know this trick works with EA82s unless its an EFI long block as there are differences with the heads and some other little bits on the block itself.

If the last EA81 was setup and running well I don't see why the intake manifold can't be swapped onto this block - unless you've exchanged it for this engine...

Cheers

Bennie

All excellent information for sure.

But the thing is ...there was no previous EA81. This is in a VW campervan. the conversion is so straightforward it's amazing. Pulling the old motor was the most time consuming part of the whole procedure. The EA81 is tiny compared to a VW Type 4 motor so installation was easy. besides the wires that the PO of the motor hacked off, the wiring took me five minutes. Fuel system 30 seconds. The rad isn't secured yet but it's there and functional. Essentially even though it isn't in a Subie everything should still apply. Besides a different flywheel and housing it's all the same, just facing backwards.
If anyone is wondering about the bodged accelerator cable in one of the pictures it's because I have to do something to it whether I stick with the Hitachi or put the Weber on. Each one requires different mods so I'm kind of fence sitting.

I converted because the motor has been giving me grief for 11 years. Parts are horribly expensive and rare to the point that most people are running motors that are incomplete somehow. when I realised it would cost less to go subie than just getting my old crusty heads refurb'd the choice was obvious.

If I had a previous EA81 I would have swapped the manifold, or just the carburettor straight in.

Being a full time father I'm working on what you could call a tight budget so I'm looking for the most economical solution. that's one reason why I'm thinking about the Weber. I spent a lot of time getting it right for a similar motor (cooling method aside). And because I seem to be looking at a messed up Hitachi it's a matter of repair, replace or substitute.

If I can escape at all this weekend I'll do the valves. I know it sounds kind of perverse but I'm almost looking forward to it. Once you have done clearances with a frame rail along the top, heat exchanger at the bottom and your head and shoulder kind of wedged into a tyre and wheel well, any small concessions are welcome.

[TOONGA]

I would love to see a twin port manifold on an ea81 motor just a bit of grinding and welding and woooo hoooo

having worked on VW engines long before I lost my hair, they do share similarities to Subaru engines and yes they are alot more compact than the VW motor which would make it easier to get at in the engine bay of a kombi

TOONGA

[steptoe]

VW camper? - Tsubaru must be somewhere near......

[El_Freddo]

Ah righto - makes sense now. I thought you had already done the conversion and was replacing the engine.

If the EA81 ever dies on you there's the Ej22 or the Ej20G Someone posted a link to a kombi that had a holden V6 conversion! They got it going and were very stoked with it. I think they're crazy myself...

Keep at it, you'll get there. Just make sure you keep the coolant up to these little motors. If you keep oil and coolant up to them they'll look after you for a long time

Cheers

Bennie

[RatCamper]

I would love to see a twin port manifold on an ea81 motor just a bit of grinding and welding and woooo hoooo

having worked on VW engines long before I lost my hair, they do share similarities to Subaru engines and yes they are alot more compact than the VW motor which would make it easier to get at in the engine bay of a kombi

TOONGA

Compact enough that I keep considering the possibility of dismantling a compressor I have which is made out of ancient truck bits, and mounting the tank in front of the motor. Remember my radiator isn't in the engine bay either so no worries there

El_Freddo: I did have those options for alternative motors, and others. But the reason i went for this setup was to dodge engineering. At about $1000 for a cert, plus the nearest engineer being over 300km away it was a good option. Besides the EA81 has a reputation for being nearly indestructible and immortal providing it doesn't overheat or generally run out of any fluids. Call me crazy but I like the simplicity of OHV pushrod motors too.
Haven't had a chance to do anything this weekend. All I could do was have a quick look at the Ford which seems to have decided to randomly stop firing. But that's a whole other story. A rotor and cap clean helped it a little. But this is about the EA81, not the Windsor.

Here's some bonus pics.

The motor before I started cleaning it:

Lots of room:

[TOONGA]

yes your engine is way cleaner now seems it had never been cleaned in the car it cam out of. on the radiator side of things are you going to mount it on the front of the Kombi or somewhere less noticeable, as years ago a friend put a 6 cylinder in his Kombi and mounted the radiator on his roo bar and ran aluminium pipes from the front to the engine bay for some reason the police didn't enjoy his enthusiasm

TOONGA

[RatCamper]

The radiator is underneath, between the frame rails and probably will stay there until I inevitably mashed it up and torn it off, at which point it will go on the roo bar.

This is a photo of the one it was pulled out of. Currently I just have it strapped on underneath until I get around to mounting it. not like it needs much securing while it's restricted to the back yard.

There is also a large wedge shaped shroud which goes under that with the opening facing backwards, so the air flows in between the frame rails in front, is assisted by thermo fans if necessary and is sucked out backwards by the shroud, when moving forward of course. It's a Camira radiator which is a three layer thing and pretty big so cooling really isn't an issue.

[TOONGA]

thats an impressive placement of a radiator and it has a protective shroud as well I dont think it would work too well on a Subaru though

TOONGA

[RatCamper]

I haven't had a chance to do anything this week
I just checked the PCV. Uh, the valve works better now. Didn't really affect anything though.

Still running smokey as. Definitely rich. I estimate 1L/min fuel usage, possibly more. I got through a 10L jerrycan in minutes. From this test and my last move across the yard / attempt to tune it.

Before you ask, the sump isn't full of fuel. The solenoid is doing its job. Seems a lot like a cactus needle valve to me.

[TOONGA]

sounds more like a hitachi that needs to go in the bin and be replaced by a working weber

but yes I would say the carby definitely needs rebuilding (or binning) when they are using that much fuel the fuel plunger is normally stuffed and so is the needle and seat

if you can get a cheap adaptor plate put the weber on and end this madness

TOONGA

[RatCamper]

I stole a few minutes yesterday to do some pointless probing on the Hitachi.

What I found was:
The shaft for the plunger has a couple of mm of slop side to side in any direction. No idea if this is normal. The vac pot for the power butterfly was kind of really crunchy and a little stiff. I guess around the moving bits was full of sand and grit. I freed it up after a bit. While I'm on the subject, I don't get the butterfly setup on this carb at all. I know how they work on mechanical progressives like the weber, and on vacuum progressives like the Mikuni I have kicking around. The mikuni has a sort of cam on the throttle shaft to prevent the power butterfly from opening unless it is near full throttle. What regulates that behaviour in the Hitachi?

I took the top of the carb because I figure nothing to lose. The float side looked adequate. No idea of the needle and seat because I couldn't figure out how to remove the linkages to totally separate the top from bottom. I could have done it like that but it would have been hard.
The throat side of the carb was kind of scary. The venturis, especially the main butterfly side look like they have been a part of the exhaust system for about 20 years. I could see through into the manifold and it didn't look black and awful like the carb throats.
All I can think of with such awful blackness is incorrect valve clearances.
I haven't been able to tackle them because the rain has kept me from outside jobs like that all week.

edit: I forgot. There is a shaft in the top plate of the Mikuni. if it corresponds to the Weber I guess it's the power valve. I pushed it a few times. It felt like it was binding on the valve housing.

[Venom]

I second a weber conversion! The hitachi's develope slop in the butterfly mechanism too which you might want to check for as well. If it is present then it will make tuning very difficult, and it's not really worth repairing. I had one wrecker refuse to sell me any Hitachi carbs because he says they're hopeless and he can't gaurantee they will work!

I went through three carbs trying to find a good Hitachi. I was in a rush and didn't have an air compressor to do a proper clean/rebuild and figured that surely one would have to work! Same problem as you describe with black smoke, fouling plugs, going through tremendous amounts of fuel. That was leaned as much as it would go.

Talking to an old subaru mechanic and some research later and i understand this problem with the Hitachi is usually caused by a fouled idle circuit. I gave up and bought a weber.

Next step is to get rid of the points distributor for a later electric one.

Cheers,
Rhys

[RatCamper]

Good news I guess. I bought some fuel and started it up. It was running so smooth. Not perfect because I still need to do the valves, points and timing, but really nice. Kind of humming. Previously every time it fired it thudded through me. The idle mixture screw was actually doing something too. So I figured I'd give it a bit of welly. As I expected it went back to rough idle with its thud thud, and blowing some smoke. So whatever it was has done it again. My guess is something in the power butterfly assembly is buggered. Weber is looking more wonderful by the day I just need to hear back from the bloke at redline in the US because I can't find a decent adapter here.

[RatCamper]

I've been sick so today was the first chance I got for anything.

Today it was the points and timing. Sort of.

The points are rubbish, but I'm broke for now so I cleaned them up and relocated the worn bit of the insulation on the wire to somewhere it couldn't touch anything. They'll do for diagnostics.
Thankfully the motor still started after that so I went ahead and guesstimated the timing at idle, vac line off of course.
Before I did the points the mark on the crank pulley was aligned with the left side of the square nub bit to the left of the case split so I set it back about there. I am speculating that the mark on the pulley corresponds with TDC when aligned with the case split, but that's just a guess like I said.
The two holes in the crank pulley don't line up with anything in particular do they?
A difference of a degree or two changed the engine note a bit and stopped the intermittent miss. Interesting but doesn't mean much. it could be running a bit retarded now. i can't tell until i do some more drastic probing.

The idle speed is about right now, it's not blowing smoke and sounds a bit better. The Hitachi is still junk though.

I still have to do the compression and the valve clearances. Given the wear on everything else I doubt the valves are adjusted.

Where can I get screws for the distributor points? The heads are pretty mangled on them. Looks like someone really wrenched on them.

[TOONGA]

you should look at getting an electronic dizzy for the engine but remember to get a matching coil as well. (yeah I know funds are an issue)

for a timing reference point you should get the engine to top dead centre, (when you have done the clearances) and make a mark some where on the engine that relates to the timing mark on the crank pulley or flywheel. theoretically that should be zero from there you can make guesses with the timing.

as for points screws the local wreckers will have some (probably still in a dizzy).

if you cant get an adaptor cheap go to a scrap merchant and buy a piece of 12mm-16mm thick aluminium and make one.

TOONGA

[RatCamper]

Things shouldn't be as rough soon. Just bad timing on a lot of things. What models are the electronic distributors from? Do they have an external control module or is it internal like some of those after market electronic ignition systems? Besides not needing to adjust the points, which is like 5 minutes every few months what are the benefits?

If I can I'm taking a stab at finding TDC today. I'll do it with a drinking straw through #1 plug hole. It should be accurate enough for my needs. More than anything it'll tell me what the mark on the pulley represents.
Once I know, I'll research the lost (to me) art of geometry to knock up a simple timing scale. When I timed it yesterday it was just a rough job with the timing strobe. I really wish I had played with these motors more in the past. I can't tell which sound at idle is the right one.

While I'm here, are there alternator brackets that don't have the fan pulley mount? Having what is essentially a knobbly idler pulley whirring away in there pointlessly bothers me a little.

Getting a chunk of aluminium for a DIY adapter was something that occurred to me too. unfortunately the nearest scrap place I know of it about 100km away. Same distance as the nearest decent wrecker. So a premade adapter doesn't seem too bad an idea especially once my shoddy precision fabricating skills and lack of a drill press come into play. Crooked holes. The throat hole I'd just go mad with the die grinder and various emery and wet/ dry paper to get a nice gradient. But the studs. Aaah! All that aside I'd be lucky to find a useable chunk of aluminium.

[RatCamper]

Update: Found TDC using a drinking straw
The mark on the pulley lines up with the case split.

[TOONGA]

the reason to use the electronic distributor is simple; it is a more reliable device, it has less wear and tear on moving parts as there are very few, you don't need to replace points and condenser every tune up and you can get rid of the ballast resistor and low voltage coil as well.

love the use of the drinking straw to find top dead centre

now that you have found top dead centre you can time your engine by small increments until under load the engine pings then back it off until you have no ping
I would say it would all be with in a centimetre or 2 of the TDC mark

TOONGA