Jump to content


Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse
 

- - - - -

EA81 Hitachi Carb rejetting


  • Please log in to reply
13 replies to this topic

#1 Guest_brattysvx_*

Guest_brattysvx_*
  • Guests

Posted 24 August 2002 - 05:22 PM

How much would I be looking at spending to get my carb rejetted. My 86 Brat is running real rich (seems to be getting richer by the day) Mpg is around 20-21. Any good place to take it around central PA?

#2 Guest_Skip_*

Guest_Skip_*
  • Guests

Posted 24 August 2002 - 08:16 PM

sounds more like a float problem rather than a jet problem

#3 Guest_beauregaardhooligan_*

Guest_beauregaardhooligan_*
  • Guests

Posted 24 August 2002 - 11:58 PM

I'm with the Skipper, clean the carb. Run your favorite cleaner thru it for at least a couple of tanks and *change those fuel filters!* If it gets too cruddy, go for a rebuild before messing with the jets. They worked good before, right?

#4 Guest_brattysvx_*

Guest_brattysvx_*
  • Guests

Posted 25 August 2002 - 07:40 AM

Well I just had an inspection and everything else seemed fine when he checked it the plugs are almost shot though after about 4k. The float is just above the circle now (I had it just below but it ran out of gas around 3500rpm). Not good on the hills. I rebuilt the carb when I got it and haven't gotten over 230 miles per tank or 22mpg.

#5 Guest_Skip_*

Guest_Skip_*
  • Guests

Posted 25 August 2002 - 08:29 AM

you say you rebuilt it.
Do you by chance remember changing the "power valve"???

I have seen these work loose (and go bad). Since they are located below the fuel level in the bowl, if they are loose and or "leaking by". The engine will run rich, and as you said, get progressively worse.

#6 Guest_brattysvx_*

Guest_brattysvx_*
  • Guests

Posted 25 August 2002 - 10:08 AM

tight as can be. Just lowered the float down to right in the middle of the circle. We'll see if that does anything but it ran rich even when it was below the circle (last set of plugs showed the tell tale signs.

#7 Guest_Skip_*

Guest_Skip_*
  • Guests

Posted 25 August 2002 - 10:34 AM

did you replace the power valve?
Some kits have one some don't,
this could still be the problem if it is leaking
or "passing gas" when it shouldn't

#8 Guest_beauregaardhooligan_*

Guest_beauregaardhooligan_*
  • Guests

Posted 25 August 2002 - 10:58 AM

If the float level is too low it will lose power in a turn, a very sensitive adjustment.
Did you replace the float valve seat and needle? There is also a filter screen in front of the float valve, be sure it's clean. Blast out any little hole/passage you can find. :cool: Wear glasses!
What about the fuel filter(s)?

#9 Guest_brattysvx_*

Guest_brattysvx_*
  • Guests

Posted 25 August 2002 - 01:10 PM

Yeah, it was a new float and needle, screen is okay and the fuel filters have been replaced twice w/o a change. I'd be happy with everything if I could just get up to around 25mpg

#10 Guest_brattysvx_*

Guest_brattysvx_*
  • Guests

Posted 29 August 2002 - 02:00 PM

So I decided to rebuilt my "parts" carb that I got from the junkyard. Spent a good 15 hours cleaning it and getting it together. Slapped it on my brat and it jumped to life. This one doesn't want to run unless the vacumn hose for the choke (those two dashpots (I think) behind the pass side of the car) is disconnected. Without it on it'll idle and run still on the rich side but after driving for a while it'll tend to stall when you come up to a light. Float's right dead center in the middle of the spot. Any thoughts out there??

#11 Guest_beauregaardhooligan_*

Guest_beauregaardhooligan_*
  • Guests

Posted 29 August 2002 - 10:16 PM

Make sure the choke is fully open when at operating temp. Lean out the fuel-to-air a half turn at a time. Don't get too lean or it can run hot.
If you lose power in a hard right you need to raise the float level.

#12 Guest_rubuild_*

Guest_rubuild_*
  • Guests

Posted 31 August 2002 - 04:56 AM

If it runs better with the choke closed or part closed you have
a massive vacuum leak or plugged idle circuit, sounds like your other carb is in better shape, reset float levell and check vacuum routing. Check that the bowl vent valve ( black round valve that clips into back of air cleaner) is connected to the very top port of carb, above fuel line fittings & not the secondary air control port on the back side. If fuel is spitting from the primary venturi at idle, you have a plugged idle circuit, and it's sucking fuel from the main circuit.

#13 Guest_brattysvx_*

Guest_brattysvx_*
  • Guests

Posted 31 August 2002 - 09:56 AM

checked everything on that bad boy. Even switched all the internals from the rich running one and it wouldn't work a bit. Just simply rebuilt the rich one and put it back it. Still seems rich but oh well no emissions testing til next year in PA. If I upgraded my coil to the accel would the plugs burn more fuel when they fired??

#14 Guest_Subi81_*

Guest_Subi81_*
  • Guests

Posted 31 August 2002 - 10:42 AM

Bratty I just had a simalar problem on my 81 wagon Hitachi. It was running so rich it wouldn't pass smog. It turned out that the primary slow jet had worked its way loose and was just floating in it's seat. The slow jets on my hitachi are the ones that are under the little plugs really deep down in a hole, they can be accessed by taking off the carb top and unscrewing the little plugs. Hope this helps

Good luck




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users