Loss of power in Leightweight

Hi. I’ve just joined this group and a month ago I got a 1971 Lightweight like the one I had in the army a long time ago. But it now loses power. Starts fine. I’ve done all the obvious things, checked the distributor, (seems ok),changed the condenser (although the old one looked fine) checked and replaced the spark plugs, old ones were dirty. Got a spark plug tester - all seem ok, all plugs fire rapidly but the light is quite dim. Checked all the cabling inc to the coil. Any ideas? It worked really well for the first 600miles. Thanks
The Admiral.

Describe what the power loss is like. Is it fine on the level and not hills, OK until you accelerate, less top speed?
How does it run when you have enough power , say doing 30 mph?

rob1miles said:

Describe what the power loss is like. Is it fine on the level and not hil

rob1miles said:

Describe what the power loss is like. Is it fine on the level and not hills, OK until you accelerate, less top speed?
How does it run when you have enough power , say doing 30 mph?

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ls, OK until you accelerate, less top speed?
How does it run when you have enough power , say doing 30 mph?

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It

It starts fine. Moves off. But won’t accelerate above 20mph. 1st and 2nd seem ok but nothing in 3rd or 4th.

The Admiral said:

It starts fine. Moves off. But won’t accelerate above 20mph. 1st and 2nd seem ok but nothing in 3rd or 4th.

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Coil, or a fuel issue, possibly a dodgy lift pump or blocked inline filter, could be a possibility.

With a username like that, shouldn't you be concentrating more on the boat side of things?

Thanks. Fuel looks fine, it runs through the filter strongly and the tank is clean. Will have to check the coil itself - do you have any tips about how to check the coil? Admiral’s an old nickname!

The Admiral said:

Thanks. Fuel looks fine, it runs through the filter strongly and the tank is clean. Will have to check the coil itself - do you have any tips about how to check the coil? Admiral’s an old nickname!

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Substitution with a known good one is the easiest way to check a coil at home.

What carburettor does it have?

Ok. I’ll get a new coil and see if that works. Carb is new and clean but I don’t know more about it than that.

The Admiral said:

Ok. I’ll get a new coil and see if that works. Carb is new and clean but I don’t know more about it than that.

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Better would be to get one off someone else's running vehicle, if you do get a new one, make sure it is quality. Old stock Lucas, and modern Lucas, are not very good.

You need to identify the carb. At that age, a civilian vehicle should have a Zenith, I think, but I know not much about military stuff.

Thanks Turboman, I’ll try that, much appreciated.

One sign of a duff coil is the casing getting hot after only a few mins, to hot to keep your hand on, be careful if you try..

Thanks. I’ll run the engine and check the coil.

http://www.retroanaconda.com/landrover/manuals/2a_owners_manual.pdf
Good fault finding section in the s2a manual

if its a weber carb on it , the main jet ,could be blocked ? well know for that

I'd be looking at blocked jets. Its been running well and now its not pulling so its being starved of fuel or sparks. Does the cab have and accelerator pump? If so try repeatedly blipping the throttle when the power is down. If this bypasses the main jet the engine will pic up. If its fed off the main jet it wont, I'm not familiar with your carb. Is the float needle clear?
Have you tried taking the air filter off, revving it and putting your hand over to pull any muck through? The other way is to rev and swivel the distributor so its spits back and blows the dirt back.