Thread: 3.5 Carby V8 hard to start when hot

G`day Garry ,

if for some reason your needles/seats/floats are not as they should be it can cause hard starting when hot also if the choke is not
shutting off/on properly it will be hard to start after use .

In both cases aerostart is unlikely to do anything .

Coarse , best plan is probably when it`s hot and won`t start look for spark and it only needs to be at 1 plug as you`ve done , if it`s not found it`s probably ignition .

cheers

EDIT
I see your looking at ignition but thought i`d suggest the temperature compensators , they let more air in when the engine is hot .

Check the Dizzy

It sounds like the the same problems as if the timing is out a lot

Really hard to start when hot loosen of the dizzy and turn it a little as you crank

If the advance mechanism has gone it may be stuck advanced this is why it starts cold but not hot or visaversa

"have seen rotor buttons do what is happening to yours..

my first v8 disco did a similar thing and it drove me nuts for two days till i swapped the rotor and away it went.

there was no visible fault on the one that was playing up and when not under load it worked just fine.. bit of heat and load and it died... "

Originally Posted by rovercare

Amazing defect, had it a few times before, was at a mates shop, D1 with 137k on the clock, gas fitted, wouldn't run right, had all new leads, plugs, cap, button, fitted by gas fitter, I said grab another cap and button, what do you know, ran like a charm

I had the same issues in my disco when a service agent replaced the rotor button with a non genuine item. The rotor button in my 101 is unique to the 101 in that it also acts as a governor, it has a little weight and spring that cut power when the engine revs too high - I have had my engine up to about 5,500 rpm and it hasn't cut out yet. The current rotor is a new genuine one installed only 2 months ago.

Garry

Originally Posted by steve_35

If the advance mechanism has gone it may be stuck advanced this is why it starts cold but not hot or visaversa

Thanks - the 24v dissy does not have vacuum advance but does have a mechanical system - I will check that it is still working.

Garry

In an attempt to solve the starting problem I replaced the plugs, points, rotor button, condenser. At the same time bought a new LPG converter and had the mixer reconditioned.

With all this work done the cold engine would not fire on petrol but would on LPG but would not continue to run on gas but would on petrol. So starting is ignition on on petrol to pump petrol into the carbies, then switch to gas and inject LPG via the cold start button into the inlet manifold - switch back to petrol and start the engine. When the engine is a bit warm the engine will run on both fuels. Warm starting is the same as cold.

So in the truck went to the Gas Tune up man who claims the engine is sucking in air through the inlet manifold gasket.

So tomorrow off come the carbs and valley gasket and in with new ones - then back to the Gas Man.

Anything special I need to look for??

I hope this all works.

Garry

Got to admit I don't know a lot about this, but would a leak in the manifold gasket produce a couple of plugs of a different colour? Mine had the same problem for awhile, ended up lowering the fuel levels in the bowls a bit, everything is worn a little in my old strongburgs!

I replaced the inlet manifold gasket - what a pain of a job.

The engine now starts and runs well on LPG but will not start on petrol either hot or cold. It does start and run ok when switched to petrol but with a squirt of LPG from the LPG cold start button. The LPG is injected direct into the manifold bypassing the carbies.

So it looks like a carby issue - I think the safest approach is to take them off and get them rebuild and setup.

Is this something I can do myself with a kit or is it best to send the carbies in for the rebuild.

Cheers

Garry