General Exhaust bracket mounts

[Veloman518]

So I had to pop the muffler off and on the brackets that mount to the engine case I had 3 studs and one bolt. I’m guessing this should have been 4 studs? The bolt was suspect and popped out on a drive and oil started spraying everywhere. Do these holes go through to the crankcase?

 

[the hobbler]

The top holes go all the way through the crankcase---the lower holes are 'blind'. The Abarth reccomended 'mod' was to tap the top holes all the way through (8mm x 1.25mm)and then fit a screw (threaded its complete length) from THE INSIDE, complete with flat washer, spring washer and done up TIGHT. For the bottom holes, use a 'finishing' tap (aka'plug') and gently tap the hole as deep as you can,and the use a stud which uses the complete depth of thread---you may have to modify a longer stud to achieve this. In both cases, the amount of thread protruding out of the crankcase must be long enough so that 2 PLAIN nuts (and a flat washer) can be used. 1 nut to tighten up on the mount and the 2nd nut to 'lock' the 1st nut. Do NOT use 'self-locking' nuts--if a self-locking nut should nip up on the top 'stud' the screw will be wound back into the crankcase. This was a standard 'Abarth' modification. If you wouldlike to e-mail me direct ([email protected]) I willlet you know all the required dimensions for the screws/studs.

 

[Veloman518]

The top holes go all the way through the crankcase---the lower holes are 'blind'. The Abarth reccomended 'mod' was to tap the top holes all the way through (8mm x 1.25mm)and then fit a screw (threaded its complete length) from THE INSIDE, complete with flat washer, spring washer and done up TIGHT. For the bottom holes, use a 'finishing' tap (aka'plug') and gently tap the hole as deep as you can,and the use a stud which uses the complete depth of thread---you may have to modify a longer stud to achieve this. In both cases, the amount of thread protruding out of the crankcase must be long enough so that 2 PLAIN nuts (and a flat washer) can be used. 1 nut to tighten up on the mount and the 2nd nut to 'lock' the 1st nut. Do NOT use 'self-locking' nuts--if a self-locking nut should nip up on the top 'stud' the screw will be wound back into the crankcase. This was a standard 'Abarth' modification. If you wouldlike to e-mail me direct ([email protected]) I willlet you know all the required dimensions for the screws/studs.

Interesting. I suspect that someone buggered up the lower hole then. There was oil everywhere and it definitely wasn’t from the dipstick. I’ve had that happen before. When I pulled over the lower bolt on the rear bracket had come loose and there was oil all over the exhaust right below it and around the bodywork. And of course now my mind wanders to what might have gotten dropped inside the crankcase? Metal bits perhaps. Nothing is ever simple…this car is trying to kill me.

 

[the hobbler]

Yes, I agree--seems as if somebody has done a bodge job in the past. The possible answer is to drop the sump and do the same mod to the bottom hole as i suggested was done to the top hole (i.e.---tap the hole all the way through the crankcase and fit a screw from the inside. You might have to us a 'cap-head (allen key) screw if 'hex-head' space if limited) Although this work willprove tedious, but not difficult, it will prove to be the sensible thing to do in the long run--it will also ensure that the exhaust brackets never come loose again!

 

[Veloman518]

Yes, I agree--seems as if somebody has done a bodge job in the past. The possible answer is to drop the sump and do the same mod to the bottom hole as i suggested was done to the top hole (i.e.---tap the hole all the way through the crankcase and fit a screw from the inside. You might have to us a 'cap-head (allen key) screw if 'hex-head' space if limited) Although this work willprove tedious, but not difficult, it will prove to be the sensible thing to do in the long run--it will also ensure that the exhaust brackets never come loose again!

Just ran a bit of piano wire into the hole….went straight into the sump so for sure that needs to be dealt with. Thanks Tom.

 

[Toshi 975]

I had a situation on one engine where one of the studs had come loose and been rattling around for some time which wore the hole out of shape. I fitted a high tensile M8 mushroom head screw from the inside, packed out the wear with JB weld then secured it in place with an M8 half nut which sat neatly under the exhaust bracket.

 

[Bleeding Knuckles]

Just ran a bit of piano wire into the hole….went straight into the sump so for sure that needs to be dealt with. Thanks Tom.

Hi, I too have carried out this mod as Tom say's make sure the setscrew or bolt is TIGHT - clean the threads and use some strong thread locker, never had a problem since.
Ian.