The Fordson Tractor Pages Forum

Hello Fordson Forum

I found this by searching the old forum. I have a similar problem with my Major, it's a petrol from 1959 fitted with a diesel engine sometime later.

"posted May 01, 2003 22:18
I have a '57 Major, fitted wiht a 64 Super Major engine. According to my documentation, there should be a crankcase breahter, wich filters the air sucked in by the crankcase with oil. My engine is equiped with a "home made" closed crankcase ventilation system. Instead of sucking in air, the air is sucked out because there is a pipe connected from the crankcase to the rocker arm cover, wich is connected with a hose to the intake manifold. Is this bad for the engine?, and can I restore it to "official" status by putting in a crankcase breather filter and discard the pipe?"


On my Major the stud on the timing gear box has been sealed, but it still has the 3/8" pipe connection from rocker cover to inlet manifold. An old Fordson mecanic tells me that they used to replace it with a 5/8" connection, by solder a new stud on the rocker cover. Is this and the solution described in the 2003 post a good idea for an engine with "undercompression" (piston ring blow by) ?

Regards Jörn (Denmark)

Fordson crancase ventalation will be the same as other vehicles of that particular period, as I understand it it goes something like this;

Some early Fordsons ( or at least the American Super six ) had a road draft tube which dumped blow by, below the engine.

The above likely also applied to early Kero engines also.
As the New Majors evolved the diesels had a tube between the inlet manafold and the rocker cover. (About 55 -57 )

In 1958 several changes occurred which included a modification to the raised PTO gearstick, different tractor identification, a different engine block ( one liner "O" ring ), different sump, different head and inlet manafold which no longer used a tube to connect the rocker cover to the inlet manafold this instead connected to the air cleaner.
The head used at this time was very similar to all the late 61 to 64 heads however cannot be used on these later models without de-rating the rocker ratio.
In Australia at least, during 1957 that the small oil bath timing gear breather was introduced, this would be necessary because the changed crankcase ventalation where less negative crancase ventalation would have resulted.
this later system had a couple of advantages over the earlier system in that excessive crankcase blow by could escape via either the air cleaner or the timing gear breather, excessive oil was much less likely to end up in the intake manafold fouling the engine, and this would have helped with trapping soil particles within the air filter and some oil may have seperated into the oil bath.

This crancase ventalation continued to be used till the end of the Fordson production as far as I know and the 6 cylinder versions of these engines used in the Thames Trader and the Fordson conversions there was a breather pipe between the rocker cover and the air filter housing and the small oil bath breather on the timing cover for fresh air to enter.

Please note that it is very bad to have a totally sealed crancase which could result if swapping componets as this will foul up the crancase oil and pressurize the gaskets and seals.

I will have to look at my books as I did not think a early inlet manafold with the rocker cover tube fitted the late cylinder heads, I can't work out which combination Jorn has without looking into this further.

Mike

From 1951 to 1957 all Majors had a tube connecting the valve cover to the inlet manifold. It was a little short tube hidden between the valve cover and the inlet manifold. After 1957 until the end of production a tube from the valve cover to the air cleaner was fitted and a intake/air cleaner was fitted on the timing cover with a cone on the auxiliary drive shaft timing gear to stop oil being thrown out of this breather.

In theory, air is drawn through the engine but crankcase pressure builds as the engine wears and the system cannot cope so oily air gets ejected via the breather and you will see some tractors with plastic bags over it. Another problem was the cone breaks off and allows oil from the timing gears to be thrown up through the breather.

The rocker fixing posts were changed in 1957 and, instead of the valve cover being held by two bolts into them, the head was machined to take 6 screws around the base of the valve cover. The valve cover no longer had the facility to fit the pipe into the manifold and this was replaced by a short stand pipe that was connected to the air cleaner as described.

Thank for your replies.

I have been busy with other things during the summer, and the Major also needs a new radiator. But time (and money) will come...

The question of crankcase ventilation is still puzzling me. I think the problem is that there are descriptions of the different solutions for mark I, II and III engines, in my workshop manual. But no ansvers to WHY. I would like the post a sketch drawing (in .bmp format) of my intentions, but can't figure out how to upload files.

Major regard Jörn

Jörn

See http://www.fordsontractorpages.nl/phpbb3/faq.php#f3r3
Titled - Can I post images?
I used photobucket.com there are other sites as well.

Greg

Thanks Fixradio

Fantastic - it's working. I hope this illustrates how I intend to change thel CCV system. The latest idea is to lead the tube to the lower part of the oilbath breather, instead of the inlet manifold.

Major regards Jörn

And with the photo functioning, I would like to present my tractor to all interested:



Nice - and now the picture are shown full size /Jörn

Jörn,

Nice looking tractor.
Also looks like you have a good place to keep and work on her.

Greg

Thanks
I use the tractor at my torp (small farm) in Sweden. I have turned the old barn into a workshop, which means that the floor is in different levels, but it's OK, I can fix almost anything there. This weekend I'm fitting a new radiator on the Major.

Did the sketch drawing illustrate how I'm thínking to change the crankcase ventilation? I'm still wondering what the best solution is.
Regards Jörn

Hugin2 wrote:Thanks
I use the tractor at my torp (small farm) in Sweden. I have turned the old barn into a workshop, which means that the floor is in different levels, but it's OK, I can fix almost anything there. This weekend I'm fitting a new radiator on the Major.

Did the sketch drawing illustrate how I'm thínking to change the crankcase ventilation? I'm still wondering what the best solution is.
Regards Jörn

Buy a small oil bath breather for the timing cover these are available new, and connect the connector towards the back of the rocker cover to the same size spout in the air cleaner inlet tube just below the point where the pre cleaner tube slides over, if your tractor is an early one it will not have this spout and you will need to bronze one into the tube.

Mike

Thanks Mike

I'll do that. Agriline has a breather eqivalent to the original. And the other connection can be made with copper tube.I'll post a picture when it's ready.

Regards Jörn

Hello Fordsons

I ended up with this solution. The tube is connected to the air cleaner, rigth next to the precleaner. It has affected the lower part of the engine positive, there are no longer pressed oil out of the timing gear housing. In the upper part the conditions are the same, oil is still sprouting out from the oilfiller cap.



Any ideas what to do next?

Regards Jörn

I haven't really checked but I think the filler cap should be totally sealed and any oil coming out would be caused by the cap not being well sealed. Most engines have some sort of baffle around anything like a vent in the rocker cover to prevent oil being flung out but the filler cap does not have any baffle.

An advantage in having two separate vents is that no one blockage cannot cause a pressurized crankcase from blowby. Pressure in a crankcase can do bad things, including forcing crankshaft seals out of position.

Just looking at the photo above. Should the 1964 Super Major engine have a decompressor lever? I thought that was only on earlier engines.

halloween wrote:Just looking at the photo above. Should the 1964 Super Major engine have a decompressor lever? I thought that was only on earlier engines.

Hi From what i can tell the early home market diesel major had one fitted and a lot of industrial power units, all the export tractors I have seen in Canada right up to the last ones in 64 have them to. I think they may have been on cold climate country export tractors. in my time in the U.K i never really saw one that was old enough with it fitted.
Regards Robert