MF-135 Engine Swap.............

[Ralex1]

Greetings,
Can anyone advise on any potential Gearbox match-up problems I would encounter if I try to swap out the original Perkins AD-3 152 Diesel "Rope Seal Engine" for a AD-3 152 Diesel "Lip Seal Engine" on my 1967 MF135UK Tractor ????
Any sound experienced advise would be appreciated...............

 

[PatrickS2222]

Hi, I have the same model tractor and know them reasonably well. I believe the bell-housing and bolt pattern is the same on both versions of engine. There are, however, many different versions of this engine. I have never carried out such a swap but it should be quite straight-forward, provided your replacement engine is the correct version for this application - otherwise the flywheel may not bolt up to the crankshaft. Also, the correct front pulley needs to be fitted - either keyed or splined shaft versions are available. Different injector pumps without a governor etc ... the list goes on.
Are you replacing the engine simply because the rear seal leaks? If so, consider overhauling it instead. Kits are very inexpensive and from several suppliers - I have done ours and it's now like a new one. Good luck!

 

[Agvg]

I do belive its just the rear seal that are different so a newer engine should fit. Are your old engine dead?

 

[Ralex1]

Apart from the excessive oil leak at the rear of the engine, the original Perkins AD-3 152 works fine. Based on overwhelming advice in forums from both sides of the Atlantic and now down under, I am going to split tractor and give it a go again. I've been told that I should consider renewing the seals on the gearbox input shaft as well as this can be a source of oil leaks. Someone suggested that the sump cork gasket could have hardened and could be spilling. I am told that the main engine oil journal has a plug at the rear of the engine (hidden by the backplate) can also develop leaks over time........... thanks for your advice.

 

[Ralex1]

Not so sure........some say that the back plate on the Lip-seal version of the Perkins AD-3 152 is bigger than the Rope-seal version and there may be some flywheel issues as well. I am going to split tractor and try to pinpoint other potential areas of leaks that I did NOT suspect before........because I made the presumption that the leaks was coming through the rope seal. Otherwise, the engine works fine......... my gut feeling is because the crankshaft was cut 0.30" undersize by the previous owner, the rope seal is not hugging tight enough. Will find out soon enough......thanks for the heads up.

 

[Agvg]

The rope seal needs to be installed by the book, and many don't do it right an gets leaks.

You should see on the color of the leaking oil if it's engine or transmission oil.

zetor_4712-6748_service_sec_wat.pdf - Google Drive

 

[Ralex1]

It is engine oil without doubt because I have to top up engine regularly and I can see the bell-housing oil-saturated. However, clutch disc "oil" contamination might be through seepage along the gearbox input shaft.
PS. By your link - Does the Zetor engine also carry a rope-seal?

 

[Agvg]

Hehe, no Zetor does not have a rope seal, the communists had much better engineers so they went with a modern design

mf135_mf150_mf165_shop_service_sec_wat.pdf - Google Drive

 

[Ralex1]

OK! I'll take your word for it.................. Never saw a Zetor Tractor in my neck of the woods. But almost every MF that was bought to my hostile "salty" Caribbean environment is still working, many in swampy rice wetlands and cane fields. And they have great resale value despite the arrival of hi-tech machines. Grateful for the pdf repair manual.

 

[Agvg]

I have a MF 135 myself, but sometimes I wish it had been more logical constructed, should had a more conventional hydraulic system that was not a tribute to Harry Ferguson, a engine mounted pump would made everything much more easy when you add on hydraulic functions.