question Zetor diesel tuning options?

[Odalsmie]

Hi!
My son is running a '78 4718, anyone have an idea of how hard this can be tuned?

 

[Joachim]

Its not a real good idea and black smoke is just your money (diesel)

The Zetor 4712 only has a 100mm bore and the "small valves" and therefore manages to achieve 45 HP on the 540 PTO.
With some work it is certainly possible to get around 5-8 more HP out of the engine - but at what risk?!

The 3 cylinders are not unknown for cooling problems on the 3rd cylinder (towards the cabin), so the engine cannot easily tolerate more diesel and therefore more heat if the power is to be used permanently.

If you have the thought of a turbo - don't do it, a grandma doesn't become a virgin.
Original Zetor turbo engines have other:
- cylinder heads
- Head gaskets
- Cooler
- Water pumps
- Fan
- Engine oil pumps

As well as additionally:
- Piston crown cooling
- Oil cooler

... to run stably and sustainably in the long term.

Next limiting factor: the gearbox. For good reason, Zetor gave the medium gearbox a maximum of 50 hp engine power and the more powerful types also had a significantly more powerful gearbox.

What I ultimately want to say is that it would probably be easier and more sensible to think about a second, stronger Zetor or replace the old one with a stronger Zetor.

Maybe all-wheel drive then? e.g. 5745 or a 6745 or something newer like 5945 / 6945 or 6045 / 7045 or even newer.
The first turbo originally delivered from the factory was the Zetor 7745, which had all the extras, as well as disc brakes, a torque converter (underload level) as well as a whole 120mm stroke instead of 110mm and a new injection pump and nozzles, which in summer ensured significantly more torque.

 

[Zetroen]

It can be tuned hard. But as Joachim stated it won't run long.. Bigger injector nozzles, more fueling, turbo etc and it will be quick for a while.

 

[jcataclism]

If you have the thought of a turbo - don't do it, a grandma doesn't become a virgin.

 

[Renze]

Most important, from 1978 onwards, the 9 series engines, had not just the bigger intake valve, but also an extra coolant channel between heads and block: Where the older heads have a frost plug in that location.

Because the block doesnt have a water channel there, its pointless to pry those frost plugs out because you wouldnt get your coolant up to mark unless the entire crankcase is filled

4911 and 5011 are easier breathing and better cooled, 5211 has the heavy 4 cylinder rear end that will easily accept a 3 cylinder turbo. Not a 4 cylinder turbo because the 7745 rear ends had different gears and ratios to account for 90hp.

 

[Joachim]

Absolutly right.