Removing a Transmission on a Yanmar 4JH4E

[Charlie]

Hi All:

I have a stripped out thread on the bolt which holds my gear shift lever on a KM35A (I think) transmission. Sorry but don't have a picture of it. It is located in a spot where it would be very difficult to drill a straight hole so I think that I am going to have to pull the transmission in order to drill in an insert. I am also very bad at drilling holes straight. My plan is to remove the transmission set it up on a drill press or to find someone with a better hand then mine and drill the hole properly. From there I will tap it. It is currently held in place with this product Permatex 81668 Stripped Thread Repair Kit : Amazon.com : Automotive I looked at the advertising and saw that it would hold 128 ft lbs. Sounded good to me. After reading the manual I found out that the holding power on it for a 6mm bolt was only between 2 and 4 ft lbs. I don't think that is enough but am not positive. 128 ft lbs was for a 1" bolt.

I was wondering if anyone had ever removed this transmission and could give me advice. One thing I was wondering is how much you would need to mover the Prop shaft aft in order to get the transmission off of whatever spline it mounts to.

Thanks in advance.

[TheOffice]

can you insert a HeliCoil into the hole.

[cal40john]

Originally Posted by TheOffice

can you insert a HeliCoil into the hole.

From OP:
pull the transmission in order to drill in an insert.

insert = helicoil

requires drilling and tapping for the helicoil to be put in.

[Charlie]

There is only 3.25" clearance between where I have to drill and the engine bed. I would have to cut the drill bit down and then use a right angle drill. I decided to try it on a small engine that I have on the bench and I didn't drill so straight. The insert is a few degrees off of where it should be. I figure If I can't get it to work when it is on the bench no way I will be able to do it in the field. Not saying "IT" can't be done. Just that I can't do it.

So anyone ever pull the transmission.

Bump

[boden36]

Can you disconnect the cable , twist the lever on the shaft to a more accessible position for drilling and then drill the existing hole right through and then use a nut and bolt to clamp it?
If you have to remove the transmission, then you will need to unbolt the prop shaft flange and slide the shaft back far enough to get clearance to move the box rearward during removal.
Remembering from my 3JH, the actual separation of the box from the engine only involves undoing the nuts or bolts around the circumference of the bellhousing and sliding the box back to extract the splined shaft from the damper plate. (after removing any ancillaries and pipes that are in the way).
The box unbolts from the bellhousing with bolts accessible only from the inside of the bellhousing.

Regards,
Richard.

[LeaseOnLife]

how far can you push the shaft back to remove the transmission? 2 inches should be enough:

http://www.yanmar.es/theme/yanmares/...M35A-35A-2.pdf

Weight of trans: ~ 13kg