How do you remove roll pins from block?

[clarkpark]

The roll pins that hold the o-rings in place are boogered up. They are also the wrong type (split pin). In fact, a couple of the o-rings were mangled by the pins.

So how do I get these pins out? I really don't want to knock them all the way in and put new ones on top if I can avoid it.

Thanks,
Clark

[KennyG]

Hi, saw your post and noticed this thread:
Food for thought re roll pins
Also, the search engine on this site works really well--it's what got me started here.
Good luck!

[clarkpark]

KennyG-

Thanks for your note. I had already read that thread, which contains a lot of useful information on which pins to use, if any.

I know that my pins are the wrong ones and are also mangled, so I need to get them out.

Thanks,
Clark

[John M]

Not speaking from expertise on this one so just being creative so take it for what its worth.

A couple of ideas come to mind. Especially if the engine is out, I would just drill them out and clean up the mess. If the engine is in, you might try cutting off the mangled head with a cut off wheel. Then insert a threaded tempered screw into the remaining pin. Then pull it out via the screw. What ever you do, don't scare the top of the block and don't use it for a prying surface.

Post a pic and let us see what you got.

Best Regards,
John M

[Lee Hjelsand]

Clark, don't dispair, there is a very easy way to remove them.
A stainless sheet metal screw is carefully inserted in the roll pin, one that is big enought to get a bite on the inside if the pin. use a phillips head screw perfered. May take a few tries to get it to bite. The roll pin is a softer metal than the screw so it will eventually. Once you have the screw in, use a side cutter to get a bite on the treads of the screw and lever it out. I takes longer to explain this but I've done it many times and I've never had one that I could not get out. A side cutter pliers is an electrician tool for cutting wire. Don't cut the screw by squeshing to tight

Lee

[DaveC]

Lee has a the perfect solution to removing the pins. I would screw in the self taping screw into the pin and using a dent puller that excepts screw heads, bang them out.

Dave

[clarkpark]

So I tried a couple of things to pull the pins out and here is what I learned:

1. Trying to run a SS sheet metal screw into a hardened roll pin only results in removing the threads from the screw (probably dumping them in the oil passage).

2. Using a hammer on a screwdriver to collapse the sides of the roll pin just busts off hunks of the roll pin (also ending up in the oil passage).

3. Using a drill slightly bigger than the ID just busts the drill (with pieces ending up you know where).

I think the main problem is that the roll pins are hardened, so I am having trouble getting anything to bite into them.

Next I will try a tap (hardened) or try using a propane torch to heat up the pin and remove the temper (hardness).

Any more suggestions?

[GTD]

Clark

1)Stainless steel screws vary in hardness according to application and manufacturer. You CAN buy SS or carbon steel screws which are hard enough to do the job as suggested-but you won't find them at Cheapo-Depot. You may find it easier to purchase TAPCON screws. These come in phillips or hex head. They are made to drive into concrete and are HARD.
2)Don't get frustrated.
3)Carbide drills are available which are MUCH harder than the roll pins but they won't tolerate chatter-from a chipped roll pin, nor variable pressure-as is typical when using a portable drill. Your BEST drill is a diamond drill; hard enough and forgiving enough but pricey!
If you try heat-use MAPP gas-much hotter than Propane.
DON'T USE A TAP. It's not designed for this.

[papajam]

Quote:

Originally Posted by clarkpark Any more suggestions?

[MrT]

You know, guys, it looks like Clark has maybe "boogered up" his roll pins. I have never seen such a hash made from instructions on any section of this bb. I am ashamed of you all. (There, Clark, doesn't that make you feel better?)

Seriously, this is a mess. Papajam's suggestion might be a workable fall-back. But..... at this point, two or three alternatives present themselves to me. I don't know whether there are two or three, beacuse I'm dreaming them up on the fly. One is analogous to the "weld a nut on a broken stud" approach. I think it is clear enough what it would involve. It should not involve any chips. And it might not work. This is impromptu. Another thing would be to pick some good high tensile strength wire and weld or swage ends on it (two pieces) just a little smaller than the hole in the roll pin. It might work to use a drop of hard solder, for instance, but make sure the wire is clean and properly fluxed. Slip one wire and bead through the roll pin. Size the second bead or file a slot in it so it will go down the roll pin center with the other wire in place. When you pull up on the first wire, appropriately in coordination with the second, the two ends might bind at the end of the roll pin. Then grab the two wires with a vise grip or similar gripping tool and carefully use a lever arrangement to pull the wires and pin out of the block. If you use the two ends of one piece of the high-tensile wire (like lawn mower control wire or perhaps multistrand wire like stainless steel controls cabling for aircraft), then you might be able simply to stick a bar through the loop and pull judiciously against an appropriate fulcrum. I think that makes two suggestions, not three. Again, remember that they are improvised on the fly. But sometimes the things I dream up actually work.

I _really_ hope this helps you. But maybe Papajam is right.

[rcess]

Papajam is right. In 1992 I had this same problem with my '69 Spider, and I just pushed them into the block and put new ones on top. Simple, easy, and it works fine.

Bob

[clarkpark]

After trying several methods, some listed above and some not, I figure the only reasonable way to get the hardened pins out is to use a high speed die grinder with 3/32" carbide ball end mill to carve them apart from the inside. Considering that my block is still in the car and this would deposit chips in the oil galley, I think the best thing is to push them into the block, like Papajam suggested.

The next question is whether or not to use the spiral pins that came with the square cut rings from Centerline? I do not see what function they would perform, since the ID of the ring is much larger than the OD of the pin, the pin would not hold the ring in position. Shouldn't the ring be held in place by the gasket?

Thanks,
Clark

[60sRacer]

Here's a bit opf rambling from an old Alfa Racer from 1969-73.

Back in the late 60's and early 70's is when these silly roll pins came up. The problem they were trying to address was that the head gasket used rubber washers to seal the oil passages from the main bearings to the camshaft bearings. These were often miss aligned and crushed so that they occluding the oil passage.

So roll pins- actually hardened steel sheet rolled up into a little coil tube with a bit of springiness to hold them in place - were stuffed into the oil passage with a bit protruding thru the head gasket (but not into the upper head oil bore) to keep silicone rubber o- rings in place.

The problem is that these roll pins themselves block 60 to 70 percent of the oil passage!!! The solution we ended up with in the 1600/1750's and early 2000's was to use small aluminum washers inside the o-ring to keep the rubber from being crushed into the oil passage, with the bore of the aluminum washer drilled to match the oil passage. Alignment was not as good as the roll pin, and relied on the head gasket hole to make it all fit correctly. But we used copper faced racing head gaskets which had precise holes for the oil passage and o-rings. I even fit and ground the aluminum washer to match the bores in each engine I built.

Every engine I used (for street, autrocross, and track) that had roll pins had to have them pulled. It was ALWAYS a variation of disaster! They are hardened! I do not know why - probably to keep them springy to hold tight - but it made pulling them tough. They were harder than any of the screws I could find, and also harder than any of the tool-steel taps I tried. I ended up making a steel tube cutter that over-bored the hole by cutting around the roll pin. (We do this in woodworking to remove the stem of broken brass screws) Think of a tube with ID slightly larger than the OD of the pin, and teeth cut on one end. Harden enough to cut aluminum, chuck in drill press or milling machine (to keep it aligned) and cut outside the pin deep enough to pull it. Usually had to go pretty much to the bottom of the pin.

Then sleeve the oversize bore with an aluminum tube and drill that to the oil passage diameter, to restore the mess you just made and get the top of the oil passage back to where it started. And strip and flush the block of all the debris you just made - any of it will grind the heck out of the cam journals, and the main bearings if it gets into them.

You don't really want to reduce the lubrication of the cams, especially if you use high lift cams with competition (stronger) springs. Ricambi, Shankle, Bobcor and a bunch of us in the Bay area all fooled around with the roll pins. I think Shankle finally retailed the o-ring/aluminum washer package we developed at Turn-One Racing.

Head gasket sealing was a major issue then. Factory maintainence evern required loosening and retightening the head bolts ion a very careful proceedure to keep the oil gallery and water passages from unsealing. Big mess when oil starts leaking doen the outisde of the block and water gets into the oil. shortlky the head gasket fails. First failure was almost always between the back two pistons as cooling water circulation was worse there, or behind the last cylinder sleeve (remember these are steel with different thermal parameters then the aluminum block) which lead to combustion chamber pressurizing the radiator!!!!!!!!!!!!

!!!

The AROC racing prep manual of the day had a lot of diagrams for re-drilling the water circulation in the block and head to combat this. I think Alfa eventually adopted the change into the later 2000 engines. But I still use racing head gaskets and carefully re-torque the head of my Duetto. It has one of my old 2000 race engines in it, and many of the suspension goodies I used then. Heavier than the cars we raced, but a scream for an old goat on Mulholland today.

[Alex]

Quote:

Originally Posted by 60sRacer Head gasket sealing was a major issue then. Factory maintainence even required loosening and re-tightening the head bolts in a very careful proceedure to keep the oil gallery and water passages from unsealing. Big mess when oil starts leaking down the outside of the block and water gets into the oil. Shortly the head gasket fails. First failure was almost always between the back two pistons as cooling water circulation was worse there, or behind the last cylinder sleeve (remember these are steel with different thermal parameters than the aluminum block) which leads to the combustion chamber pressurizing the radiator!!!!!!!!!!!! The AROC racing prep manual of the day had a lot of diagrams for re-drilling the water circulation in the block and head to combat this. I think Alfa eventually adopted the change into the later 2000 engines. But I still use racing head gaskets and carefully re-torque the head of my Duetto.

[dfrye]

I've got these pesky pins knocked down into my block as well. Since I am only fixing a broken head gasket, and not rebuilding the block, I am wary of using screws or anything else that might drop metal filings down the oil channels.

I do however have access to a set of the proper roll pins (the ones that wrap around themselves not like the ones in the photo) so am considering driving the existing pins further into the block.

I am assuming that the resistance to oil pressure is not significant in any of these devices - they do reduce the oil channel area significantly - what do you think?

//dean