Here at VTE we often get questions from people as they go about their restorations.  Here’s one that has come in from Matthew…

 

Hello,

I’m in the middle of overhauling the hydraulics system on my MF65, using the fantastic DVD by Ian.

I’ve also got hold of a copy of the original MF workshop manual for the 65 (which also covers the 35 and 50 in the hydraulics section).

I’m a bit confused by the oil grade and I wondered if you could advise me.

In the manual it says the transmission/hydraulics should have 80 grade oil if it’s cold and 90 grade if it’s hot. I had thought I’d just put in multigrade 80/90 oil in. But I noted last night that you say in the film that it should have 50 grade oil but that 15/40 multiuse oil would be just as good. Since there’s a big difference between 80/90 and 15/40 oil I thought I’d ask you advice. 80/90 does seem very thick for external hydraulics, but it’s also for the transmission and axle… What do you think? Is 15/40 multiuse oil able to protect the transmission sufficiently?

Thanks for your help, and thank you for having produced the DVD. i’m intending to buy your engine overhaul DVD for the 4 cylinder MF835 engine (my donor 835 was dismantled partially years ago and has been outside for over a year (before I bought it) so I’m going to finish stripping it and it would be great to decide what’s still servicable and what needs to go for scrap.

I did find you hydraulics DVD very good and it’s good to hear your pieces of advice and experience during the process – things they don’t print in the manuals. Like you special tools for turning the top cover – works a treat.

I look forward to hearing from you soon. I guess you get a lot of questions, so I hope you will be able to find a couple of minutes to adivise me regarding the greasers, o-rings and oil choice.

Matthew

 

Hi Matthew,
Re: oil type, The original oil for the gearbox recomended for temperate regions is the SAE50 grade, with a move to SAE40 and then SAE30 as the temperature decreases and a similar move the other way as temp goes up. Nowadays we would suggest a move to a tractor universal oil ( 15w/40 or 15w/30) for climates like ours (UK). Even the  MF branded HC Plus used in the modern tractors is ok to use all the way back to the 35s. I feel that the 80 or 90 grades would be much too viscus for the hydraulics and unable to pass through the filter, however although not recomended the thicker grades may be a posibility for tractors operating in hot climates which are not fitted with the hydraulic system.
The spec for the 80/90 oil will be for the reduction hubs on the rear axle of the 65. These are sealed from the center housing.