Bell housing dowel Pin puller
 

I have been looking for a bell housing dowel pin puller and haven't had any luck. I find plenty of pullers, but they don't go up past 1/2". GM dowel pins are 5/8". Does anyone know of a source? I need to install some offset pins for bell housing alignment.

Hole open on the back side to tap them out?

I drilled and tapped mine for a 3/8 bolt and used a slide hammer

If its a blind hole - sometimes you can use a thread tap.
Just keep on turning it as it bottoms out in the hole and the dowel will thread its way up the tap, and out.
Use some PB Blaster spray ahead of time, to start with.

Its one of the ways we get old starter bushings out of bellhousings on older model VW Diesels.
They are a pressed fit into a blind hole of an aluminum casting.

Weld a bolt to it and slide hammer it out.

goodson makes a puller with a 5/8 arbor
i just drill a hole down center and tap 1/4 or 5/16
use a threaded rod and a nut and a spacer that fits over pin and is longer than pin and turn nut and they pull right out

i was thinking of a hollow dowel
- my fault if its not a hollow one.
Been so long since i held a Pontiac bellhousing i can't even remember what type of dowels are in them.

Some really good suggestions by these other guys.

Put a nut over it and weld it on, put some heat on it, then hit it with some WD40 or the like, it will twist right out.

Thanks guys for all the tips. I appreciate them but I really would like to buy an actual puller if possible. My machine shop has one made by Snap On that work's on 5/8" pins but it's really pricey. I'm always having to pull the pins and replace them with longer ones when we dyno engines, or I use an adapter or mid-plate. All the suggestions above to get the pins out destroys them or is fairly time consuming.

Still looking for an actual reasonably priced puller if anyone knows or has one.

Gary,
Procure a cheap slide hammer w/ 1/2" threads. Use the attached conversion coupling nut. drill the 5/8" side out to fit over dowel. drill one (or2) sides for set screw (s). I you need a longer one, you could weld one 1/2" coupling nut to a 5/8" coupling nut. Drill 5/8 coupling nut and tap for set screw (s)...
Whallachinga….cheap dowel pin puller!

https://www.mcmaster.com/91072A333

This is a pretty cool idea! Sounds like it will work, and be usable multible times. I think I'll try it. Thanks to everyone for the responses!

It is a blind hole, no access from the other side (as the oil passages are on the passenger side) and the drivers side has casting material supporting the bellhousing bolt hole on that side as well as the Starter Mount ear of the block.

The dowels on the 3 blocks I looked at all had a very short exposed length before the taper so getting a gripping tool on the dowel would be very difficult.

Drilling/Tapping the dowels is the only choice. I personally would prefer to use a drilled and tapped dowel and then a circular ring larger than the dowel to allow the dowel to be pulled from the block using a washer, bolt and breaker bar/socket.

Too many chances to break the block using the bottom of the dowel hole as the "force point" to force the dowel from the block bore.

Richie H. has the right method.

Tom V.

No Tom, you're wrong. You CAN use a puller to pull the pins. My machine shop has one made by Snap On that will work on the GM 5/8" pins. When we dyno engines at his shop he uses it to replace the stock pins with the longer ones. Works great! I just don't want to spend Snap On type money to buy a puller that I only use 2 -3 times a year

Just post up the number of Pontiac Engines, not chevy, ford, etc that he has used this puller on in the last 6 months.

Not saying that the snap on puller will not pull the dowel pins on GM engines.
So how many Pontiac engines has he dynoed in the last 6 months.

Then you can say I am wrong. One or two isn't a representative size as the dowels may have already been removed at least once prior to your dyno session.

Tom V.

I usually use a length of 1/4" steel strap with a hole drilled into it and MIG weld it over the dowel, the heat from the welding makes it easy to just twist and pry the dowel out.

Good grief, I've had 10 or more Pontiac engines dyno'd or needed mid plates or adapters installed that we've pulled the pins for. It's not even debatable.......but you will.

Happy for you, good day
Tom V.

Question, installing a .100 mid plate. Can I leave the stock dowel pins as is ?

I would say maybe...when I went to a Lakewood scatter shield with a .125 block plate I had to change to longer dowels but it was close.

I agree, I just installed a .100 adapter plate for a Pontiac to 700 R-4 conversion and I decided to go ahead and put the longer dowels in. It's a customers car and I'd rather be safe than sorry with it.