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cheap tricks/tips for the hitachi carbs


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I had an 87dl just got a 87 GL. same carb, different heads (thankfully) with hardly an egr problem like my dl.

After taking carb all apart one day on my dl due to bad idle or no idle, I cleaned it up got it going again. I noticed the 1st barrell you putt around town with hardly gave power, from the day I got it, seemingly uncurable. This gl I just bought is doing same thing- no power before half throttle. My dl was cured with a 5-7 psi after-oem fuel pump and it not only fixed it, the old dl moved right along. Started flawlessly down to a -23f degrees.So, it was to learn that it wasn't even a rebuild necessary, it was the oem fuel pump. Any other tips for the hitachi? I will be running one for several months (possibly).

A problem I had was throttle sticking wide open, unannounced on my DL. The gl doesn't have the same cylinder heads with "too much egr" so I am hoping this problem is non-existent now. Anyone have this sticky throttle problem on a gl with no "asv" ports on cylinder heads? I am hoping not.It especially happened to me if moisture was in air below 32 degrees. I further fixed that problem down into the single digits (a little better) but the chance still existed to stick. I have no idea what I did to fix it, that little bit, except for fuel pump,and never cured it entirely. I guessed it to be way too much egr. My car had asv on both heads and an egr port like spfi - all oem.Bad bad ingredients for anomolies to say the least.3 ways to cram hot exhaust back into the head, plus the oem heat riser... ridiculously dangerous.

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The throttle sticking has nothing to do with the EGR, and everything to do with the throttle. There is a little rubber cap on the end near the carb, and some times pieces of it break away and they then get caught between the cable and the cam actuator, happened on my SPFI motor, whoa was that scary.

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GD:

It was in fact a flawed egr. Do you need scientific evidence? there is a special place you can stick your cars exhaust pipe, to experiment and then see how fast you run to get away by instinct.. except it is a never ending supply of exhaust pipe, and you run faster to get away and it feeds this special spot the pipe is CRAMMED with even more , so you run faster to get away...and it feeds it even more....then you can't breathe and the finale is a 9000 rpm fireball of toxic purple aluminum flaming your experimental AREA.

Get it? you call it metaphor. I call it analogy.:rolleyes:

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GD:

It was in fact a flawed egr. Do you need scientific evidence? there is a special place you can stick your cars exhaust pipe, to experiment and then see how fast you run to get away by instinct.. except it is a never ending supply of exhaust pipe, and you run faster to get away and it feeds this special spot the pipe is CRAMMED with even more , so you run faster to get away...and it feeds it even more....then you can't breathe and the finale is a 9000 rpm fireball of toxic purple aluminum flaming your experimental AREA.

Get it? you call it metaphor. I call it analogy.:rolleyes:

 

Fantastic! You win... how's it feel? :clap:

 

Now it's back to reality for me :burnout:

 

GD

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If I were to meet you in real life. ....would we babble until friendly or a knockdown argument :confused:

Anyway, once again. The world is not my place, and neither is yours. Problems unique encountering each other can bring prejudicial opinionated facts with out any real truth to stand on.

The previous statement is exactly why presidents like Bush go to Iraq.

"reality for me" was a great thing to say there. It is the same to say for myself. :)

The hitachi carb on the 87 just purchased is in thorough detail in a chiltons. The adjustments are something I remember. Very simple carb, problems could only be quick to find- unless there is a 2 headed 3 way egr system I haven't ever seen again like on my dl (thankfully). This GL should be a breeze. Anyone use the 5-7lb fuel pump on the carbed sube? I had great results with it on my other 87. Gained power and fuel mileage.

Once again, different than a manual with facts, I went about it my own way successfully. The book states 3.3 lbs pressure for the 2bbl 328 hitachi. That is odd. I bet the sube pump is proprietary numbers, unlike the 5-7 lb which is everywhere. Even the idle got thumpier, low end, etc.

Upopn other carbs cfm similar, the 5lb pump is thier norm. I am certain after running spfi and carb, Subarus conservative side was pushing the limits, rather than the approach to give it all it can handle.

Oh- the egr will be plated. will post a 1600x1200 size macro view of it just for you GD :lol:

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Here is an example of what does not work with a hitachi carb. 4-7 psi facet. I bought this in an emergency side of the road repair job in a friendly landowners driveway. Strangely enough I bought another with advice form an advance auto parts expert and the same pressure worked even better than oem with the different pump given. Will post that one soon. I can't remember brand names. It was a large pump that hung off the fuel pump plate and ran literally silent for 40 bucks. I am assuming this one with "posi-flow" had no passive and caved something in at the carb. I had to prime it to start, but once running there was plenty of pressure.

 

facetfuelpump47ep8.jpg

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I like the hitachi. As plagued as it may get- it is because we let it. :)

Cleaning a needle valve out and changing the entire stochiometric curve doesn't necassarily need an ecu- The electric choke and its adjustments is a must have. Any "after" electric chokes on the market that fit hitachi? I know coils break in all of them eventually...

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dude, have you ever worked with a weber???

 

it is SOOOO much easier than damn near any other downdraft carb on the planet, and its super-tunable.. people EVERYWHERE with all sorts of cars have oodles of experience with them, so "help" is not an issue, EVER.. they made about 239578478698239 of them so there are parts EVERYWHERE.... and i mean, you can just pick and choose your needles, jets, and venturis on the fly.. its more malleable than any EA-82 EFI system shy of megasquirt...

 

My impression has not been that the hitachi is such an awful carb, but primarily that the weber is just like, the carburetor from planet Krypton or something. NO carb (not solex, not S/U, not even a lawnmower carburetor) that i have EVER worked on was as simple as a weber. theyre practically toilet mechanisms with adjustable jetting :grin:

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the hitachi functioning like new at 20 below zero is incredible. I don't know as a simpler carb would be as smart. I used to get right into the holleys for v8s and they all had problems. The hitachi just simply doesn't have the same probs.

I did spot some webers out there, even new ones. A bit steep for price, but I would no doubt use one.

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and BGD, why does your car have "red-eye" in your avatar foto???? did i miss something???

 

the "bowl" in that carburetor is for FUEL that is destined to be burnt and utilized for its chemical composition.. NOT SOMETHING ELSE...... :burnout :lol::burnout:

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I finally remembered the probs from my other 87. The linkage broke in two spots trying to adjust,one was choke the other a kickdown to slow idle- both in same area of left side of carb (passenger) and a needle valve was dirty, and there was a backfire problem thru carb caused from something that was hellbent on loosening up on its own. I went by the chiltons version of setting float- adjusted the weakened choke- and wow. A freakin masterpiece in all weather.40mpg+ on the highway was the result.

The total cost was nothing but my time and a coat hanger (a very strong metal one mind you- my 20guage snips wouldn't cut it ). I may run into a prob without the super duty coat hanger. what am I supposed to purchase to replace the linkages? wire guage and density ideas? I just assume hand make another if the metal is good. :) The oem stuff went "brittle" lost flexibility. I just got this one going on twenty, I am counting on it needing all of it, and then some.maybe a whole gasket kit for carb.

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