power problem

[Tsur Sadan]

Hi
i need some help with my series III 2.6L
thes land rover was locked out for many years (it have very little Km on).
i succesid to start it, but i have a power problem.
the land rover works and sound perfect in neutral, but it very weak when it
run.( it dont have power to mouv on 4 gear.)
it is run better with the choke pulled out.(the carburetter was repair
separate from the car.)
i thought it can be a bad mixture ratio? can i adjust it with an ordinary
hexagon tool? (it a zenith )
the other thought i hade it is the ignition timing, what degree i am looking
for, and did it after or before T.D.C.(i use 96 octane fuel)

thanks
Tsur

[Disco]

The first thing to check is that the carburettor throttle is opening fully, then check that the carburettor jets are not blocked.

[Tsur Sadan]

the throttle opening is a good idea! i will check it.
the jets i believe it o.k. it came back from cleaning recently.

[Duck Toller]

This sounds like a classic case of "dirty fuel tank". Check the fuel filter(s), gas tank pick-up tube, fuel pump filter screen, carb. float chamber. Start with the easiest first and work back towards the tank. Also how old is the gas? If you used what was in it when you got the vehicle or just added to it that may also be part of the problem.
Let us know if this helps.

[Tsur Sadan]

thanks
fuel tank and car bwas renewal,filters was changed .but i will check the fuel lines

[TerryS]

As Disco says, I also tend to think you may have a clogged mainjet. An engine can run at idle, especially if fuel flow is aided by the increased draw when the choke is applied. It isn't necessarily producing any appreciable horsepower though. Once power is demanded, there isn't sufficient fuel to make it.
As another pointed out, the restriction may also be upstream of the carburator, as well as fuel pump with a faulty, worn out or cracked diaphragm. If at all possible tap a pressure guage into the fuel line where it meets the carb and see if you are getting at least 4 PSI.(preferably 6-7) If so, then I would suggest a carefull teardown and inspection of the carb, including float valve needle and seat, Main Jet, and that their is no aluminum oxide blocking the passageways. The wrong kind of cleaning solution can make a good carb go bad in about 2 minutes of soaking.

[Duck Toller]

I didn't read the post enought. The newer Zenith carbs have a MAJOR problem with base warp. There was/is a screw-up with these. One way to check is to remove the carb., clean the base, set it on a piece of glass and see if it's flat against it all around. You can also use something to coat the base and set it down on the glass and then lift it up to see if it is warped. If it is you can use emery type sand paper to smooth it down and make it flat again, just keep checking it with the glass. A new Zenith will most likely have the same problem if not right away then a little later on. You could change over to another carb. but try the warp test first. This has really been talked up on several other BBS for Land-Rover.
Jim

[Duck Toller]

7.8:1 compression ratio.........
2 deg....ATDC when using 90 octane fuel
6 deg....ATDC when using 85 octane fuel

This is from the manual.

[Tsur Sadan]

thanks you all for the good suggestions.
i will work on the fuel system all the way.

[Bogatyr]

DuckToller,
One thing about that warp...a newbie might not know that the warp that you are referring to is on the top side of the lower carb half, where the two parts of the carb mate up.

Bogatyr

[Duck Toller]

Quite right I was a little murky on that. I had that problem with my SIIA 109 4 banger and just switched over to the Rochester. I did help the guy I gave it to correct the warp and it worked fine and maybe still is working he moved to Maine and we lost touch. The URL for a better description is..http://www.fourfold.org/LR_FAQ/Serie...enith.fix.html