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Iveco Engine

From the Walker manual it appears the Iveco engine is "de-tuned". Does anyone have any information on un-detuning it or what power improvents I can do or what might be the cause for low power?

I'm not looking for a race car, just want to make sure I am getting the full potential from the old girl.

It seems to run fine otherwise.

Also, any leads on acquiring an engine manual?

My bus number (if any): RM2133

Re: Iveco Engine

Other than checking to see that it gets full throttle and has clean oil, fuel and air leave well alone. Leave well alone. It ain't broke.

Re: Iveco Engine

Thanks, I don't plan on doing anything drastic.

How do I check if it gets full throttle?

And what is that oddball unit in between the pedal and the Fuel Control? Looks like some sort of coordinator. Couldn't find it in the manual.

The throttle linkage to the Fuel Control comes from there.

My bus number (if any): RM2133

Re: Iveco Engine

Disconnect linkage from side of pump, open pump by hand with engine running, if it goes faster, there is too much play in the linkage. A common fault in Iveco RMs, they won't pull the skin off a rice pudding.

My bus number (if any): RML2532

Re: Iveco Engine

Can anyone point me to fuel pump removal and reinstallation information?

My bus number (if any): RM2133

Re: Iveco Engine

The Walker Manual has a bit on it - as you know it’s on the fire wall side - difficult to access - it states difficult to refit with engine in situ because of need to rotate the pump to engage master spline on the drive coupling - viewing timing marks is nigh impossible - in situ pump change not recommended

My bus number (if any): RML2747

Re: Iveco Engine

Remove the drag link, grille , radiator, steering wheel, drivers seat and the cab floor, then you can see and reach. Or do as they say. None of the dismantling is very challenging unless you ate all the pies. You do not have to remove the pump to increase the sealed revs or fuelling. BUT YOU DO THAT ENTIRELY AT YOUR OWN RISK. I am not going to tell you how to do it.

Re: Iveco Engine

I plan on fitting a different engine/transmission combination within a couple of years anyway, either Cummins, International or CAT.

We have a lot of hills here in British Columbia and I need to be able to climb them to go to music festivals and events so a little more power would be useful.


Re: Iveco Engine

I don't know what your exhaust emissions regulations are in Vancouver, but you will run into problems with the engine's clean exhaust limit if you try to increase revs and particularly fuelling by more than the smallest amount. ie black smoke. It will not matter whether the vehicle is exempt from regulations because of its age or not, if it blacks you are going to attract unwanted attention from the auhthorities.

The engine in your bus is not far short of 30 years old. You will probably have heard of the term fatigue life in relation to aircraft components. The same applies to engine parts, they will eventually fail because of accumulated duty cycle.

London does have hills but in the main its bus routes are not especially hilly. In modern terms all of the engine types fitted to the RM are seriously underpowered, the bus coped in service because within London it usually didn't have to travel more than about 400 yards between stops so its road speed and that of the general traffic was not high. When fully loaded all, but noticeably the Iveco powered buses, were sluggish and had to be driven hard to keep to time.The circumstances of citybus duty result in shorter engine life between overhauls than other applications.

Given the above and known experience related in another tread about worn Iveco engines, which yours will be, shows that it does not take kindly to attempts to increase its power output. The actual amount achievable without a complete engine overhaul and this engine is not the simplest to do, is likely to be scarcely noticeable. If the engine has full throttle and a clean air filter then it is more than likely due an ovehaul. This is a marine engine, I suggest you consult marine engineers locally who have experience with it. Unless you are trying to overcome a starting, leak or misfire issue and are fully aware of the consequences of doing half a job then leave alone or do what is needed.

Even if you plan to change the gearbox as well as the engine in an attempt to increase power you still have the issue of the torque input capacity of the final drive. If you change gearbox you will also run into problems with powering the braking system. If you susbstitute an engine with a higher idling speed then you will also have problems with the actual brake system operation and if keeping the existing gearbox there will be issues regarding its torque input capacity. The fluid flywheel is designed for an engine with a significantly lower idling speed than more modern engines.

IIRC the IH DT466 and the D 358, just like the Cummins have right hand side exhaust manifolds, this will create clearance problems with the cab firewall and again IIRC Caterpillar engines are the same. The problems do not stop there, physically mounting the engine will in most cases require redesigned crossmembers and those used with the Cummins C series engine have a reputation for creating a hard riding front end with significant steering shake.

None of this is as easy as it seems.

Re: Iveco Engine

Thanks for the advice. I am going to adjust the valve clearances and leave it at that.