Cummins V8 555 & 903

evening all. been reading all your comments on V8 cummins very interesting. I actually run a1982 white road boss with its original VT903@350 hp.i've put over 800,000 km in the 16 years i've had it. She's pretty sick now[water in oil,oil leaks,leaky injectors] but she starts on the coldest mornings and spent many a day well overloaded carting scap steel and concrete products. Pushed hard i get about 4.5 mpg and she'll go 20,000 km with no oil top up from since i've had her. My job now is not so hard on her now so she gets about 6mpg, i usually change oil @23/25000 km. I think one of problems with the 903 or 555/190 is over-revving as some blokes had them @3500rpm [esp 903] which was asure way to kill them. I remember an old truckie who ran a555 then 903 successfully by keeping the revs down and revved it hard when needed which is pretty much how you shoud drive a 4 stroke motor.

Got any pics of your Road Boss mate?There is another one up here with a VT903 in it that had the front axle knocked out of it that the bloke is going to fix up.It is a very tidy origonal truck.There is also an Autocar for sale here with a VT 903 in it.

Cam do you have a photo of the autocar, be interesting to see thanks

Havn`t got a pic Chester,Ronny might have the blokes details,otherwise I can make a call and see if I can get the number,

All

Some of the above posts have prompted some more memories.

'Overreving' - that was a killer - and as part of the Cummins/International reworks on the V555 - was to wind the max revs back by about 300RPM.

'Cam Shaft failures" - I seem to recall that was a failing across the whole Cummins engine range. A wornout cam lobe was the first thing to look for once an engine developed a miss. I think the cam shafts were also prone to breaking in half. And I think the introduction of the 'BIG CAM' in the NTC 350's was an attempt to fix the cam shaft issues.

'Loose Flywheels" - another V555 feature. I seem to remember that too was part of the 555 upgrade process. New, special flywheel bolts and lock tabs was the supposed fix I think. However - the max revs/over reving was the real cause. The last few hundred revs seemed to introduce a balance problem.

Like always - I stand being corrected.

Oldfulla

OlFulla
GuddayM8
Now I no why me never got to stir a cumminz along

being brought up on Screemin 2 stroke diesels
we B the oposite of cumminz n luv the revs
tipical 2 stroke plenty of revs n drive m as tho its stolen
can also remeber a customer with a WABCO 101f Scraper
twaz 555 Cumminz derated n if he stopped the motor @ any time it would always need laffin (Aerostart) gas to get it go n again
even when donk iz hot
LOL
Cya

[ch9786]

g'day cam will get some photos posted. if that bloke with the axle out can,t get a white axle i fitted a rockwell fg931 f/axle to a79 road boss has same axle centres[34 inch] just needed to ream out steering arm [on stub axle] as white steering joint has slighty diff taper

g,day swishy I remember driving a 8v71t with 20spd spicer was like a kid with a new toy would pass a mates 350 cummins going up westgate bridge he'd say i was half loaded but a semi tipper is always over loaded esp with a load of mud