Dowel Pin Stuck

[indr]

The picture is of the bottom of the upper half of the crankcase.

(bottom half of the picture)


The dowel hooks onto the bearing on the driveshaft to prevent spinnage of the outer race of the bearing.

The dowel is supposed to be sticking out but it is some how lodged and flush with the case with no where to grab onto.

How to take out?

[Twilight Error]

If the pin is tight enough to not spin, try running a tap in there to grab it.

[twinjet]

Originally Posted by indr

The picture is of the bottom of the upper half of the crankcase.


(bottom half of the picture)


The dowel hooks onto the bearing on the driveshaft to prevent spinnage of the outer race of the bearing.

The dowel is supposed to be sticking out but it is some how lodged and flush with the case with no where to grab onto.

How to take out?

If the dowel is hollow all its length, find a solid dowel that will just slip into the stuck hollow dowel, fill the cavity with oil then tap the solid dowel into the hollow dowel. Hydraulic pressure will force the hollow dowel out. (wear safety goggles).
If the stuck dowel is solid, drill a smaller diameter hole from the other side and use a suitably sized drift pin to drive the dowel out from above.

[indr]

The dowel is hollow all the way down. Where it sets in the crankcase, there is an oil passage drilled into the crankcase itself; i.e. there's no way to build up pressure.. So, using hydraulic pressure won't work.

Drilling a hole from the other side would mean drilling through the crankcase.

[WRW9751]

Snap and Mac make inside/outside pliers. A little heat and a pair of those pliers might just do the trick.

[mouthfulloflake]

drive a self tapping screw into it, and then use a slide hammer to pull the screw out, hopefully with the dowel pin on it.

[bomber60015]

Originally Posted by indr

The dowel is hollow all the way down. Where it sets in the crankcase, there is an oil passage drilled into the crankcase itself; i.e. there's no way to build up pressure.. So, using hydraulic pressure won't work.

Drilling a hole from the other side would mean drilling through the crankcase.

then find a tap of the appropriate size, and be prepared to destroy it . . . . sometimes, an easy out (or similar) will rotate teh pin enough that it begins to walk out on it's own . . ..

[indr]

Originally Posted by WRW9751

Snap and Mac make inside/outside pliers. A little heat and a pair of those pliers might just do the trick.

Do you mean circlip pliers? I have those, the tips are too big to fit. The inside diameter of the dowel is only ~3.35 mm.

[indr]

It is also not possible to send something inside to hook the dowel from the bottom and pull it out because the oil passage the dowel sits on has a diameter small than the inside diameter of the dowel.

I tired drilling (deWalt bits) the dowel from the top to maybe crack and break it and fish out the pieces but it seems to be made out of really hard steel.

[twinjet]

Originally Posted by indr

The dowel is hollow all the way down. Where it sets in the crankcase, there is an oil passage drilled into the crankcase itself; i.e. there's no way to build up pressure.. So, using hydraulic pressure won't work.

Drilling a hole from the other side would mean drilling through the crankcase.

Is this a car engine crankcase? Is the oil galley plugged above the dowel? Sometimes oil galleys are drilled then plugged at one end.

[indr]

Bike engine. The first pic might have been a bit confusing so here' another:



The hole in which the dowel rests is machined into the crankcase. And that hole is flow through.

[indr]

Also JB Weld doesn't seem to stick to it very well.

[Twilight Error]

Originally Posted by indr

Also JB Weld doesn't seem to stick to it very well.

Your best bet is a tap or an Easy-Out. The tap will create swarf that will need to be controlled, The easy-out may jam the pin tighter against the bore.

[bomber60015]

dowel pins ARE made of stern stuff . . . . . . .drilling will be messy . . . . try to get it to turn

[sieg]

Easy out to grab and turn the dowel, while heating the aluminum case. The case will expand faster and greater than the steel dowel therefor freeing the dowel.