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I was driving my Pinz at 100 kph, then it started making a burbling sound, and I lost about 5 kph. The first thing I checked was the timing, and the distributor cap and rotor. I have also checked my valve adjustment, and the condition of the spark plugs. I'm not very good with carbs. I have checked the float level, cleaned, and sync'd the carbs, (best of my ability). I have also cleaned and changed both fuel filters, and checked the fuel pump. So, it runs fine at a idle, and mid rpm range, at high rpm the front carb starts spitting gas out the top and makes a burbling type sound. Don't know if it's my ajustment or something I missed. It ran like a top for over a 1000 kms, then did this suddenly, need a little help.

Points or electronic ignition?

Ed

electronic

I’d be tempted to do a compression test (leak down test if you can), if for no other reason than to rule out compression related issues. Kind of grasping at straws here as I don’t have a better suggestion.

Ed

Spitting back normally means the mixture is too weak and/or the timing is retarded so it might be worth having a play with that to start with.

I have checked the timing again, didn't change anything. I have also changed the fuel mixture, doesn't seem to make a difference. the problem starts to build at about mid rpm. I even rechecked the valves again. I haven't done a compression test yet, hoping I missing something simple. Even checked the voltage to the ign it was at 19 volts.

Put a temp guage/gun on all the cylinders, at idle and at the higher rpm where it starts to cut out, to see if there is a large diffrence in the temps of one cylinder. Getting the temps is easy and you don't have to take anything apart, it also tells you about whats going on with each individual cylinder. Once you've isolated the cylinder thats half the battle.

Miles

Check tHe rev limiter, it could be going bad... If you're only cutting out at higher rpms.

Possible coil issue?

http://real4x4forums.com/PinzgauerBBS/v ... oil+recall

Just a shot in the dark.

Ed

I'm curious why only the front carb has the spitting/burbling issues? Is it possible this has to do with a cracked intake from that carb, thus running lean? Or perhaps a valve spring which has gotten weak and only acting weird at high rpms? (I know you already checked them...)

I'd second the pyrometer to see if this shows up on just a single cylinder or more.

Also, from memory, isn't that rev-limiter easy to override? If so, you could try that and see if the problem disappears.

A few things come to mind: intake valve lash too tight or worn valve, weak fuel pump/low volume, worn accellerator pump, crossed wires.
Firing order is 1 2 4 3

I would however start with a compression test.

I bypassed the rpm limiter with no effect. I did a compression test and got 150-145-150-145, in that order. The coil is putting out good spark. I did have a little carbon on #3 spark plug.

Have you checked the fuel filter and the gas tank? Maybe debris in the intake tube or a filter plugged with red death? Bad accelerator pump in the carb?

I have cleaned the fuel pump screen ( it was clean), and changed the fuel filter. I swapped the pumps when I was setting the float level to see if it made a difference, no change.

Check the wire to the radio suppressor. Mine was holding on by one strand of the stranded wire. Can't get much voltage through that one little bit of copper, cuts out.

$.02