b61pickup

I am getting ready to swap out a 673 for a e-6 285 with a 5 speed. Will I have to change anything about the rad. other than clean it? Is it big enough to cool this engine. I will be using this truck as a big pickup mostly to just drive around and sometimes pull a gooseneck horse trailer.

Hi, I have a b61 with a 673 and the starter is on the driver side from the factory. I am in the process of installing a 676 285 and 5 speed in mine and although I have not got that far as yet by the measurements I have taken it should all fit with no major probelms. I know the blocks are all the basic same size.

My 673 has the starter on the driver side

Sounds to me like it used to sound when the 5 speeds first came out. Everyone hit a hill let it fall to about 1700 yanked it out of 5th gear and stoped and started over. My advice would be fix the tach and let it fall to 1300 before you downshift, wether you used the clutch or not. If you take it out of gear too soon it will not go down till the truck slows down a lot like Lmackattack saids. Dont feel bad tho because 80% of the driver that first got them when they came out had the same problems,including me.

To adjust the clutch you adjust the pressure plate internally to get between 1\2 and 9\16 between the throwout bearing and clutch brake, then adjust the linkage to get 1\8 between the fingers and the bearing.after this is done measure the free play( whatever it is,is right at this time) and when you loose 1\2 of whatever you have it is time to adjust again. This is from the spicer book.

I am wondering what all I will have to change to take a 285 maxidyne and 5 speed trans out of an F model and put it in a B61?

I vote for the Maxidyne for reliability and just love the 5 speed trans,, but was wondering if it would be possable or even worth it to put on 4-V heads

HI, I am David Williams and live in Valdosta,Ga. I operate a small trucking co. from here that runs mostly the southeast. My family has been in the trucking business since the mule and wagon days, for real,. Whne trucks came along theu started using mostly Macks. MY dad bought the first Maxidyne in an F model shipped the the southeast in 1967. Before that he ran B models when they were new. I now have a 1959 B 61 that I am fixing up to pull my Gooseneck horse trailer with, I think it will look and be better than one of those new freightliner sport's and a lot less than $100,000. I also have a 1964 B 67 with the big alum. rad. that I may restore also. I have a 1989 R model that I use on the road to replace my peterbilts when they are in for repairs. I have been around Mack trucks for 40 yrs but this is the first restoration on a truck I have tried so I will have a few questions about how and where to find the parts I want to use and change to so thanks in advance. Also thanks to watts mack for providing a place like this.