Gearbox to adaptor plate bolts

[Chris01573]

Hi All, based on the parts manual (and rimmers) there are 9 x 1.5" 5/16 bolts and then 1 x 3" 5/16 bolt (bottom Right hole in the pic) and then 2 x 3/8" 1.5" and 2 x 3/8 1.75" bolts. Having doen some searching on here I believe that two of the 3/8" bolts are a tight fit to act as dowels.. This makes sense from what I can see on the gearbox, however nothing in the parts catalogue or Rimmer about the two longer 5/16" bolts needed where I have marked. I think 2" would be what is required as the casting is thicker on the adaptor plate where these two go. what is the score with the two tight fitting 3/8" bolts I think I read these were special bolts with a short 5/16" threaded section at the end to allow nuts to fit them as its too tight for 3/8" nuts ?

I have marked on the bell housing where I think the 3/8" bolts go. there are three holes that are unused and dont exist on the adaptor plate and then at the bottom left two holes which need the longer 5/16" bolts that are not shown in any of the catalogue / Rimmers pics.

IMG_1849.jpg

[sujitroy]

LDparts made or still makes a special 2 inch bolt. I found a tight tolerance bolt for the other hole

[Chris01573]

Thanks Sujit, I am thinking of making up some dowels to replace the two 3/8" bolts might help with fitting the gearbox when the engine is in the car ? Which are the "problem Bolts" to get to when the gearbox is being fitted with the engine in situ.. I asumm the top ones but is it all of them or just a couple ?

[richardthestag]

top, but mainly the two between the back of the LH head and just above the starter motor. you will wish you assembled on the floor and installed as a single unit

[Chris01573]

So the diagrams seem to show that there are no washers or split washers on the engine side of the adaptor plate. But there are slit washers under the bolt heads. Is this correct. seems back to front to me.

[sujitroy]

what helped me get the gearbox on the engine from underneath was to temporarily use 3 inch long bolts and slide the box on the bolts. obviously you can't use may bolts as they won't fit but enough to use as a guide.

[jbuckl]

The usual suspects supply kits for this job…. Only for manual and missing the dowel essentials.

[flying farmer]

Make your life easy and tap the adaptor plate top holes to 3/8 UNC (same size as the exhaust manifold bolts). It is then possible to do all the top bolts from under the car with a 9/16th socket and a couple of long extension bars.
I have done at least 5 adaptor plates like this, literally saves hours and loads of bad language when replacing a gearbox.

Neil