Hitachi Fail in 720

[Humboldt]

It has that peek a boo window instead of the big glass, but I will try. What am I looking for? Empty? Too full?

[datzenmike]

The road from Gold River to Tahsis is still 'unimproved'.

[Lockleaf]

It has that peek a boo window instead of the big glass, but I will try. What am I looking for? Empty? Too full?

I have a Hitachi on my 720 z22 powered 510. I hate that crap tiny window, so i stole the full size view glass from a 620. Swapped right on.

[datzenmike]

Fuel should be visible.

[Humboldt]

I just started it let the electric choke cycle, kicked it down, it went to sh*t. I will post again when less depressed.

[datzenmike]

Turn ignition on off on off..... you should hear a soft click from the idle cut solenoid at the rear of the carb. No click, no idle fuel.

 

You can unscrew the idle mixture adjustment screw (count the turns so it goes back the same) and remove the idle cut solenoid. (watch out for the spring and spindle inside) Use a can of carb spray that comes with a red straw to direct the spray. Blast out the two holes to clear any dirt or obstruction.

[Humboldt]

Took the idle cut solenoid off and cleaned it. Fussed with the idle screw but didn't remove it and spray clean. Prabably should do but suffering Spring cold--snot attack. Even with idle solenoid spring and spindle removed dies at idle. Seems fine at rev. Where to buy non China Weber? or are they all, these days?

[datzenmike]

Take the idle cut solenoid and the mixture screw out but count the turns. Use a carb cleaner in a spray can with the plastic straw. Force the spray into both holes. Spray should shoot out either hole and one air bleed inside the carb so don't get in eyes.

 

Replace everything. Get running and be sure idle is below 1,000. Adjust idle mixture screw. Idle should improve and engine rev up slightly. Keep adjusting the idle speed down and setting the mixture for the fastest smooth idle. Alternate lowering the idle speed and adjusting the idle mixture till you cannot improve the idle quality an the idle speed is about 700-800 RPMs.

 

If idle won't go below 1,000+ try turning the mixture screw out to richen the idle mixture and then try turning the idle speed screw down.

[Humboldt]

Do I have to take the carb off to spray the idle screw hole?

[datzenmike]

Not at all.

[Humboldt]

10-4. I have a dead hitachi from a parts truck that I will go through the process first on the bench. Neighbor touts the idea of revving then hand cover carb intake momentarily to suck crud out of carb. Doesn't sound like the remedy for idle, so I will go ahead with simultaneous  blasting idle screw hole  and anti deisel solenoid hole approach tomorrow hopefully.

Ironically, lawnmower motor went on strike. Tore it down before realizing possible culprit water in gas. Truck won't run: challenging problem. Lawnmower won't run: major crisis. LOL

[racerx]

Just remember how many turns it took to take it out

[Humboldt]

Blasted out the mix jet hole and idle shutoff solenoid jet hole. Did the hand over carb throat deal to suck out gunk. It still won't idle. Neighbor helper who is a real mechanic saw that it is peeing fuel into the carb, like the float vave isn't shutting. I have a clogged float valve jet or waterlogged (gas saturated) float. I will take that bolt on top of the carb over the float valve out and spray carb cleaner. I am dreading taking that carb off. It is impossible to see in that tiny window if the float is floating.

[datzenmike]

 Place rags under the front and remove the front cover. If careful clean the rubber seal and it is reusable. Watch for any parts that may be loosened and fall out. The rag should be placed to catch any gas or dropped part. Float should easily lift up (use a pencil tip) and when the top is evenly level, the needle valve should be close to the proper setting. Close enough to run at least. There are two tabs that can be bent to adjust the float.

 

Yes remove the banjo fitting and unscrew the needle valve holder and clean it out. Could be a bit of dirt causing the needle valve to not seal.

[Humboldt]

Couldn't get the 12mm float jet nut loose. The 17 mm one it is secured into broke free and I couldn't get the 12 loose without crimpng the metal gas intake pipe. So I just shot the gas intake pipe with carb cleaner and put it back together. I got it to run fine but it still won't idle unless the idle set screw is turned in to way high revs.

[Humboldt]

I am getting to the point of simplifying this truck beyond the point of no resale return (once you own a vehicle and get it smogged, like I did 3 years ago you don't have to smog again). I have a bare bones intake manifold. This would eliminate the complexity and I would buy a Weber. I have a simple square port L16 exhaust manifold that I removed all but one (stuck) of the steel tubes. Can someone remind me where to get the plugs and what thread etc? 

[racerx]

Yep, get a 32/36 weber. U set it a forget it. Make sure its a real one, no EMPI, knock off crap.

[datzenmike]

Take one of the tubes with the threads on it with you. Probably metric pipe threads? Or fill hole with weld.

[Humboldt]

I did a Ratun search datzenmike, and found an old thread where you suggested pipe plugs. I went to the local hardware store with the one of the pieces that holds the tubes in and found the brass pug with the same threads  (SAE) but they were out of them. It was a sunny day so I went over to my Wagon project and took the passenger door panel off and got the loor lock cylinder out, and yes, it had the key code stamped on it. I will get a key cut Monday. The key I have been using is from a gass cap and you have to fiddle with it to get it to work. My son says, "Just pretend you have Parkinsons." No thanks.

[Jeno007]

Hahaha!

[Humboldt]

Before I bite the bullet and go Weber, I just took out the idle cut solenoid and mix adjust screw and bombed both holes with Carb cleaner again. I also replaced the spring and needle piston thing in the solenoid, which I had removed. Due to the fact that the thing just won't idle, I am thinking the problem has to be in the idle jet. So this time I am letting the carb cleaner sit in there for a while, like overnight. I am first going to shut the ignition on and off a couple times to cycle the solenoid. I am thinking the problem can't be a faulty solenoid, or wire to it because it wouldn't idle even when I took that needle piston and spring out. Besides, it clicked when I tested it before. 

[datzenmike]

Solenoid is for shutting off fuel. If the pin is removed it can't be the solenoid.

 

 

Hows the timing? Too retarded will lack enough power to idle. I think the L20B was about 12 degrees BTDC.

 

Any manifold air leak will prevent idling. Carb gasket or manifold to head.

 

Tight valve lash will also leak intake vacuum. Just make sure all rocker arms wiggle slightly with the cam lobe UP.

[Humboldt]

I'll keep trying. Fortunately I walk to work.

[Humboldt]

Hey, Datzen Mike,

I'm looking at page 81 of the Hanes. To advance timing I turn the dizzy housing counterclockwise? Also, when you say "valve lash" are you talking about setting valve clearances or is their something else with the rockers? Thanks.

[d.p]

Hey, Datzen Mike,

I'm looking at page 81 of the Hanes. To advance timing I turn the dizzy housing counterclockwise? Also, when you say "valve lash" are you talking about setting valve clearances or is their something else with the rockers? Thanks.

 

Yeah...valve lash http://community.ratsun.net/topic/16539-l-series-valve-adjustment/