Ok so most of the different stuff you guys know.
Just to recap here are the differences I found.
Tuesday night – The early M42 cam sensor reads off the front side of the exhaust cam and is about 28mm long. The M44 reads off the back side of the inlet cam and is shorter (I don’t know exactly how much but I had to make a 8mm adaptor up).
The Upper timing covers between the early and late M42 and M44 are all different. The M44 is unique to the M44 head.
There are the commonly known things such as the water temp sensor has 4 wires on the late M42/M44 and the early M42 has 2 sensors (one for the dash and one for the ECU). The rocker cover vent on the early M42 is at the front. The late M42 and the M44 have it at the back on the rocker cover on the inlet side. Also on the M44 rocker cover is all the oil squirter stuff for the “roller cam”.
On the M42 the car heater inlet is on the inlet side of the head at the back on the bottom edge. On the M44 it has a separate plastic fitting on the back of the head.
It was about this stage and at 2230 that I decided to call it a day. To progress I needed to do the following:
- Make an adaptor for the cam sensor or get another cam sensor (not an option due to cost and availability where I am).
- Get upper timing cover gaskets.
- Change over all my tired M42 timing gear to the near new looking M44 gear.
Wednesday night- during the day I had made up an aluminium adaptor/spacer plate to fit my M42 cam sensor into the M44 upper timing cover.
Note to ones self – if you do this make it to the size of eth M44 mounting pad. It is slightly bigger than the m42 one. The result is that I have to use RTV to ensure it sealed properly. It works but looks dodgy.
When fitting the M44 timing guides to the M42 they are all “bolt in” swaps except the bottom one under the crank cog, it doesn’t fit!
The moveable side guide (the one the piston pushes on) ha a different mounting hole on the bottom. You will need the M44 mounting bolt to go with it, just swap it over where the M42 post is screwed into the engine. The fixed guide on the other side is a straight swap. If you swap over the timing guides you will need the M44 lower timing cover, as the mounting bolt for the movable guide won’t fit under the M42 cover.
With my timing gear safely swapped for the near new looking M44 gear we went about fitting the head. It is all pretty standard stuff following the Bentley procedure. We finished after midnight with the head torqued up, the cams fitted and rough timing of the cam gears. I didn’t have a torque wrench for the cam retainers so called it a night after midnight!!!.
Thursday night – back into it with a ¼ drive torque wrench and torqued up very thing that is a 10mm bolt and a few others, including the cam retainers and the cam gears.
After timing the cams, tuning it over by hand, adjusting the gears again and turning it over again about 3 times I was happy that the timing was as good as I could get it.
I ended up spacing it so that the inlet cam gear post is coming ½ way onto the sensor when the exhaust cam gear post would be leaving the sensor. I figured ½ a post difference is pretty close and I couldn’t get anymore adjustment out of it anyways.
I then set about getting all the anciliaries bolted up. Aircon compressor, water pump, power steering, alternator etc, and finished with everything except the upper and lower inlet manifolds to be fitted. I had also fitted the M44 valve cover (remember the oil squirter stuff?).
About ½ past midnight called it quits again.
Friday afternoon looked promising. I cleaned up the inlet manifold and refitted the injectors, then fitted it to the head.
Now was when my boat sank….. The upper manifold will not fit with the M44 manifold. The vent at the back of the cover was not letting the upper manifold fit on by about 1 inch. So I pulled the upper inlet and the valve cover off again.
I started to compare the M44 and M42 rocker cover construction and noted the following:
The inlet side of cover has a pate that bolts into both covers but they are different. The M42 cover has a plate on the exhaust side that is fixed (permanently) to the rocker cover, the M44 one is bolted in. The oil squirter on the M44 is fed from a post on the head that pushes on a banjo bolt to feed the oil to the squirter tube. The brackets that hold the squirter tube into the rocker cover are all spot welded on.
The banjo bolt was mounted on a post that was cast into the M44 cover, the M42 had no such beast.
My plan was this. Swap all the M44 stuff into the M42 rocker cover.
I’ll explain this in the next post.
Topic: My new head change (Read 4574 times)