375 has no power, stalls

[DerChristian]

Hello there!

After a long time (bought a house and stables...) i found some time for my Ural again.
It was sitting for two years now, and i had to redo the main braking cylinders (?) which turn air preasure into hydraulic for the wheel brake cylinders.
I had to clean the fuel system too, water destroyed the filter mesh in the tank and the fuel pump membrane got bad - a classic.

After two days the truck idles great again on quite low revs and has nearly no misfires.
When i push down the gas hard it stutters a second but revs up after that.
When i want to drive and give it a bit of gas and release the clutch it stalls.

Is it just the accelerator pump in the carb?
Or the timing that is not correct?
I am trying to set the timing right now, but the shielded ignition is kind of different. Is this already an electronic ignition? I'm kinda confused right now.

The books tells me to remove the cap of the distributor and adjust the contacts - there are none...

[Grommet1]

If it's electronic ignition it shouldn't have points and it's unlikely for the timing to go off unless it has been tinkered with.
Check the vacuum advance if it has one. The diaphragm in that may have gone so it won't move the timing on acceleration.
I'm not sure if it also has centrifugal advance but if it has the weights may have seized. Normall you can turn the rotor arm a short way and it springs back if it has it.
Yes the accelerator pump washer may be knackered. I think you might see if it squirts into the carb with the engine off and air filter off if the carb is full.
With a new fuel pump and tank filter you should have sufficient fuel flow. Check the float/fuel level in the carb. Does it have a window? If not you can connect a clear pipe to the drain port and measure the fuel level next to the carb.
Give the carb a good clean. An ultrasonic cleaner for the jets is useful and doesn't damage them. Check all the channels with carb cleaner sprayed through them.
Hope that gets you going.
Cheers
John

[Grommet1]

Oh and check or clean the air filter. Is it an oil bath type?

[DerChristian]

Thank you very much for your answer!

It is indeed an electronic ignition. I found images yesterday working with google translate etc... (how to Upload images? Still photobucket?)

But how do i time those? can/must they be manually adjusted? (Already loosened it from the octane-adjuster to see if i can take it apart, though it was the mechanical distributor)
I only know the mechanical one from my UAZ...

All my Handbooks refer to the breaker/points type ignition distributors.

Centrifugal advance is not seized, it springs back like you said. Air Filter is an oil bath type, oil and filter look good but i'll clean it out with some gas.

Will check the vacuum advance, accelerator pump and float level too, there is a bolthole where you can check the fuel level.
I used to have a big ultrasonic cleaner, seems like it is time for a new one...

[Grommet1]

It's a good opportunity to overhaul the carburettor if the vacuum advance is working and no blocked or split tubes or diaphragm.
The kits for the carb don't seem to include a new cup washer for the accelerator pump. I didn't fully solve mine until I replaced the carburettor. The old seal was sticking.

[DerChristian]

Ultrasonic cleaner and a box of carburetor cleaner are ordered.
I'll work on the rest now, thanks to holiday.

Do i have to adjust the electronic ignition again? I turned the top of the distributor when i tried to remove it.

[Grommet1]

If the distributor body has been released and rotated or the octane adjuster moved then yes you'll need to reset the timing. If you just took the cap off then it should be fine

[DerChristian]

I have to reset it then. How do i do that on such a distributor?
With an test lamp, putting cylinder one in place marked on the pulley and turning the distributor that it closes at that point?
And i dont have to or can adjust something else then?
I have no experience with those ignition systems, sorry.

[Grommet1]

Yes that's correct. You can use a meter or a lamp and set cylinder one so the marks on the flywheel align with the rotor arm pointing to cyl 1 on the distributor. You can work out cyl one by following the lead from the RH front cylinder to the cap or it might be marked on the distributor or cap.

[MrRussian]

If you are putting your foot down, and getting spitting/popping/flatness. Your enrichment throttle pump is not working. Very common fault. Throttle pump has leather top hat seal that dries out if left. To be absolutely sure this is the fault, whilst engine is running, remove air filter pipe and with a touch get a friend to rev engine. Underneath choke flap, you'll see throttle jets. These should gush out petrol out of both jets only when throttling. If petrol just dribbles out unevenly. Then remove carb and change leather plunger. Also, look at the 3mm ball bearing valve in base of throttle chamber. It's a steel ball seated in a aluminium base, the ball can be stuck (electrolysis).

Keep an eye on your fuel pump as well. But, when these fail usually your Ural engine will fail to start or when running they'll stop.

Also, check all low tension connectors are screwed correctly. We had a misfire on one whilst driving back from Czech once.

There's a good chance this originated from me years ago. Word of advice regarding leaving and petrol engine standing. Modern E10 petrol is not great. Its better to use E5 super unleaded if not using the Ural. And, start/run the engine every 6 months and get it warm.

I hope this helps. R

[DerChristian]

Hello.

Ultrasonic-cleaning the Carb right now.
The Accelerator-Pump leather plunger is working, at least when the engine is not running.

I always use E5 as fuel for the oldies, had many Problems with E10 even in the lawnmower....

What do you mean with low tension connectors?

I'll work on the carb now, maybe reinstall it later. Tomorrow i'll try to set the timing again.
Where do i connect the lamp to on the electronic Distributor? I think i can figure that out, but maybe someone knows by heart

When the truck is running again i'll road register it and drive it on a regular basis... figuring out those problems is not fun.

[Grommet1]

From memory connect the lamp to earth and to the terminal on the coil which the distributor wire connects to

[DerChristian]

Long time no see, sorry for that.
I Cleaned the Carb, noticing that some Jets hat the small red ring seals on them and others did not. I'll order a complete parts kit for the carb now and put it together again.
The electronic ignition is not fun to adjust, as i can't get the lamp to stay on, only when i turn the Distributor it will light up for a moment at the point it sends the voltage through.
it is pretty much dialed in now, but not as precise as i wanted it to.

Had to do a lot in the last few Months, putting the Ural on a much lower priority.
I'll try to keep you posted on any Progress i make regarding the Truck.
Greetings.