Massey Harris 744D

I have a soft spot for Massey Harris tractors as my brother and I started wheat farming with a second hand $400 Massey Harris 745
About 10 years ago I saw a Massey Harris 744D row crop model for sale in Gayndah so I bought it and got it delivered on a back load.
It started easily and drove around quite well .As I don't have enough sheds to fit all my tractors it sat outside where I covered all openings to the weather with tin cans and periodically being turned over with the crank handle.Last week when I went to turn it over it was seized which surprised me as it was turning over when last checked in January.I dropped all the flood damage work ,towed it to the shed and removed the injectors and put a mixture of ATF and thinners down the hole left it for a few days still no luck. A freind came around and we tried again,he on the crank handble and I had a 500mm shifter on the crank nut. Still no movement so I decided to take the head off

I am impressed with the build of this motor but some things intrigued me as in the photo below there were a mixture of Whitworth and AF nuts and some metric on the injectors

To be continued as time permits

The injector pump can also freeze up and stop the motor turning......using force might break something.

Mine turns over but believe that injector pump plungers are stuck so it won't start/run. Nice smooth motor, but provides a good illustration of 'torque rise' when going through a tough patch. ie there is none.

mammoth wrote: Mine turns over but believe that injector pump plungers are stuck so it won't start/run. Nice smooth motor, but provides a good illustration of 'torque rise' when going through a tough patch. ie there is none.

My book on the Perkins P series motors says it has a bore of 3.5 in X stroke of 5 in 4.73 litres displacement 46 BHP at 1500 rpm.
Small bore and long stroke don't produce much torque

I have a Farmall diesel here with a mixture of threads and spanner sizes on the fuel system which is CAV pump and Bosch injectors.

Hopefully nothing serious wrong with yours.

Jarrod.

Next step take off the tappet cover.

The engine breather pipe goes from the tappet cover to this junction'it unscrewed easily but wouldn't come out as it was held in by carbon so I soaked it in thinners and it came out later

The tappet cover off, next step take off the tappets

I tried taking off the water pump but no success, I found there is a piece missing from the fan pulley

The pushrods don't come out,I thought they would come out from below with the head off but they don't
I set up a chain block from the frontend loader bucket by chain and lifted off the head

And there is the culprit.No4 cylinder has water in it and has seized the motor

All the P series Perks get excessive main bearing wear....on a P6 its usually the rear 3 mains will be badly worn........Fortunately ,the thin shell type bearings are still available,however early motors have thick bronze shells that need to be line bored,and are no longer available anyway.......the rods are the same....thin shell in late motors,thick in early ones........The P6 in my Coles crane seized because the fine mesh oil strainer in the sump choked with sludge......fortunately ,it seized on one rod ,and the mains were OK ,because they were thick shell.........I reground the rod journal ,and fitted one 020 bearing to a thin shell rod........and the motor went good for as long as I could climb into the old beast.....which I can no longer do.

Well thats the best outcome for a P6 Perkins

I reckon the are just a huge lump of junk, from my experience anyway

And especially when compared to the 6354

All stupidity aside from me, Im pretty sure you can get rings etc, or could get them 30 years ago

I was told that as the timing chain stretches the injector pump goes slowly out of time and this makes for hard starting and gutless operation, the two reasons I fell out of love with a P6

So probably disregard my ramblings

Paul

I was shocked when I was told about the engine siezing up. As Oliver said it had all openings covered and with a tarp over the lot as well. This tractor to me is one that needs to be kept running and to be presented as it is now in its ''working clothese''. You can make out the stencilling on the tinware and just commands respect. Not sure if anything else has been found wrong but it would be intersting to know how water got inside #4, via head gasket?
I hope to hear it running again in the near future and maybe see it at the Rally this year.