Cracked block (1 Viewer)

[rsbcruiser]

Drilling the second set of pins

I drilled the second set of pins. Notice one of the holes near center is slightly larger than the others. I let the bit drift over a previously set pin. The drill ripped the old pin out. There is enough material left to tap so I'm hoping no need to call SnL for a larger pin. The process is forgiving enough, When drilling these holes, I was most concerned to make sure there was overlap with the last set of pins

 

[aksnowryder]

Looks good. Be great if there is enough metal to hold a pin in the first hole again. I imagine holding that steady without a jig and using a hand drill is why they sell the jig. Did you find the metal of the pins to be any harder or softer then the block? Just wondering, I would think either way would increase the risk of drifting the bit.

Thanks for the update.

 

[rsbcruiser]

Looks good. Be great if there is enough metal to hold a pin in the first hole again. I imagine holding that steady without a jig and using a hand drill is why they sell the jig. Did you find the metal of the pins to be any harder or softer then the block? Just wondering, I would think either way would increase the risk of drifting the bit.

Thanks for the update.

The metal in the pins is definiteley harder than the cast iron. I drifted the drill because I did such a terrible job grinding the pins. The surface was just too uneven.

 

[rsbcruiser]

Driving the second set of pins.

Yep sure enough, disaster. This picture shows the second set of driven pins and the hole that is indeed too big for the L series pin. Looks like I will be calling LnS for a larger pin and tap. I should have taken greater care when grinding the pins. The resulting uneven surface caused my bit to drift over an old pin, ripping the pin out. Oh bother.

 

[Dano]

check this product out. it is quite the process but i haven't heard anything bad about it. http://www.locknstitch.com/

 

[fastjim11]

check this product out. it is quite the process but i haven't heard anything bad about it. http://www.locknstitch.com/

duh!;p

 

[FJ40.]

ouch!! or well .. try again with a bigger pin i quess!!!

kinda reminds me of the saying ... "if all else fails use a bigger hammer"

 

[rsbcruiser]

ouch!! or well .. try again with a bigger pin i quess!!!

kinda reminds me of the saying ... "if all else fails use a bigger hammer"

My phylosophy exactly

 

[rsbcruiser]

Third set of pins and root cause

I took more care to grind flat this time. I also used the # 3 centerdrill to make my start points. It was a bad idea to skip the centerdrill step last time, paid the price. Started to drill and realized the SnL titano trick bit was toast. Chucked the other uber trick bit and went to work. Broke throught the cast iron, bit bit into the pin remnant below the surface and bendola, second bit, toast. Went to my hss stub bits, same result snap city for the first one. Picked the remnants, chucked another bit. By the time I finished these three holes I had figured what had happened to that oversized 4th hole and how to rescue this project. The bit had snagged a pin remnant, breaking and hogging the hole out. I saved this project by taking extreme care when drilling the pin remnants out. Two conclusions, One, Pay close attention to your pin interval. Another very good reason to use the drilling jig. Second, boy was I wrong, either the SnL titano bits blow and or they are not the right application, hss bits won this battle.

 

[aksnowryder]

With two rows complete and the third drilled out, how do you feel about the process? Do you think she will handle the long term heat and stress?

My guess is the jig would have helped. Hindsight... ugh... always 20/20 isn't it?

Looking good from the pics though. Looks very promising. Thanks for the updates.

 

[Coolerman]

Awesome write-up complete with real world oops!


Could you not make up a drilling jig with guide holes in it to help line up the next hole exactly? Butt it up against the last pin, center the hole exactly over the crack, then drill a divot. Then place your vertical drill guide over the divot and drill a perfectly vertical hole, insert the pin then place the spacing guide against that pin and repeat?

Or do they say to space them out a certain way and fill in the gaps?

 

[rsbcruiser]

With two rows complete and the third drilled out, how do you feel about the process? Do you think she will handle the long term heat and stress?

My guess is the jig would have helped. Hindsight... ugh... always 20/20 isn't it?

Looking good from the pics though. Looks very promising. Thanks for the updates.

Rows? probably just a word thing so sorry if obvious but all pins are in one row. As far as I feel about the process, I think it will work great. I have decided to haul the engine down to Bearing Services, have it rebuilt. They will pressure test my work. Dudes down there say it is commonn to have small leaks and more work. Betting my work holds. Let you know. Ya and the jig at $85 dollars looks alot better now that I just dumped $50 on some larger pins and another tap. Must say here though if one was less cavalier with their spacing than I, a drill guide would be unneeded.

 

[aksnowryder]

Yeah sorry, I understand it is all in one row. Just multiple times over the same one, hence my phrasing "rows."

 

[rsbcruiser]

Awesome write-up complete with real world oops!


Could you not make up a drilling jig with guide holes in it to help line up the next hole exactly? Butt it up against the last pin, center the hole exactly over the crack, then drill a divot. Then place your vertical drill guide over the divot and drill a perfectly vertical hole, insert the pin then place the spacing guide against that pin and repeat?

Or do they say to space them out a certain way and fill in the gaps?

Thanks Coolerman, good to know there are people paying attention. It would be better to see someone pull a save out of this. Making a jig (especially if you had a mill, would be a good way to save $85. LnS states an ideal interval, overlap but the video also shows the guy doing it freehand, one hole at a time, no measuring. Apparently, as long as there is overlap, you are good. I disagree though, the more overlap you have, the greater chance of having difficulty breaking drill bits.

 

[rsbcruiser]

Plugging the gaps

This picture shows tapping of the last hole in the lower section. I had to use a magnifying glass to find the gaps between pins in the section below the big hole. I blew the spacing down there, forcing me to drill and pin three more cycles to finish this section. I am leaving the area around the hole alone until I can fill the oversized hole with a larger pin. I contacted SnL today, they have a larger L8 series pin. Relief, a block saver to the tune of $50 for the pins and the appropriate tap. A drill guide at $85 dollars, looking like a better investment. By this time I had drilling down. I used a magnifying glass to locate, my # 3 centerdrill to carefully establish a good deep drilling point. No more broken drill bits. I drilled slow with enough pressure to make chips (powder, bad). Breaking through the cast iron I drilled through slowly and carefully, clearing the pin remnants sticking below the surface. My # 7 hss stub drill bit stood up to the torture well. now I have to wait for a SnL shipment to finish this project. Then off to Bearing Services for a pressure test and machining.

 

[IDave]

Hope you're right about it holding. As I said before, I never saw some of my cracks until the engine was warmed up. Assuming all you had was all you saw in the original pix, you should be ok.

 

[rsbcruiser]

Hope you're right about it holding. As I said before, I never saw some of my cracks until the engine was warmed up. Assuming all you had was all you saw in the original pix, you should be ok.

I'm thinking the same IDave. But in any case, Brian down at Bering Services (guys rebuilding my block) said there are other things that can be done. He didn't mention Pin_heads suggestion, using the high nickle welding rod to weld over the pins. Fairly sure I got all of the crack and that there was only one crack.

 

[Pin_Head]

We never used these pins in leak repair. We only used them to repair iron castings by welding. I guess they didn't have enough leaks to go around.

Their purpose in welding repair is very different. The screws extend through the welding heat affected zone to give mechanical strenght to the joint, but they don't have to seal anything. I'm betting that it seals and if not, you might have to put a couple more plugs in it. This method of repairing cracks was old when I took machine shop, and that was a long time ago.

 

[n2666s]

Rick, awsome thread.........have switched to carbide drill bits when I have to do some serial drilling in hard stuff along with tapping oil..........absolutely HATE to bust an HSS drill bit then try to figure how to get it out

Lou

 

[rsbcruiser]

Rick, awsome thread.........have switched to carbide drill bits when I have to do some serial drilling in hard stuff along with tapping oil..........absolutely HATE to bust an HSS drill bit then try to figure how to get it out

Lou

Carbide! serious? Wow, now that's a serious case of the Not efin around. With the carbide though you've got to keep in mind that that stuff is brittle.