found something in cylinder #1 after honing

[cholag]

As you can see in the pictures those spots are pointing toward

the front of the engine block. But I am scared that those could be hot spots and possibly melt or blow a hole in the cylinder wall, what do you guys think?

 

Also I forgot to add that I had bought ARP head and main studs along with rod bolts and I read on here that I had to torque the head stud nut just 10 more foot pounds, so that would make it 70ft. lb. not 60ft. lb. But I haven't read anything on main studs so would I just torque those down another 10 ft. lb. as well?

[naviathan]

Those spots do look a little....off? I'd have that block tested before doing anything else with it.

[dr_hunt]

As you can see in the pictures those spots are pointing toward

the front of the engine block. But I am scared that those could be hot spots and possibly melt or blow a hole in the cylinder wall, what do you guys think?

 

Also I forgot to add that I had bought ARP head and main studs along with rod bolts and I read on here that I had to torque the head stud nut just 10 more foot pounds, so that would make it 70ft. lb. not 60ft. lb. But I haven't read anything on main studs so would I just torque those down another 10 ft. lb. as well?

 

It looks like you honed that with a ball hone. Doesn't look like you honed it very much either. IMO those appear to be high spots or perhaps some aluminum that was stuck to the cylinder wall.

 

I'd suggest you have it honed with a stone type hone, that way you can remove high spots if they are minor anyway.

[TravRMK]

I agree, it looks like aluminum deposits to me also.

[cholag]

Well I did use a stone hone, but I think I know what it could be now. I looked at it again, when I was punching out the front core, welsh, or freeze plug (I said the three terms for it that I know to accommodate everyone) I had drove the plug to far in and it put a hole in the plug. It looked like I hit the cylinder wall from the out side and both those marks line up with where I hit it with the punch. The one on the right is more noticeable because thats the side I hit the most. So can I still run the motor hard with those spots and what should the torque setting be on my drill for the honing process because I had mine set to 10, I think.

[ShaggyZ]

[jeffp]

if you did that damage punching out the freeze plugs, my recommendation is to get another block. Damaging the cylinder like that is not a reliable block, and that looks like just about the place the rinds end up at TDC.

One of the things about doing repairs and building aomething to begin with is that YOU DON"T CREATE DAMAGE IN THE PROCESS OF THE REPAIR!

You would be surprised how many times you see someone assembling new parts and create damage in the process, not good at all.

Myself, if I realized I nailed the cylinder wall that hard to create that much damage, I would not hesitate to replace the block.

[dr_hunt]

 

 

:shock: :shock: :shock:

[cholag]

:cry2::cry2::cry2::cry2: I dont want to replace it, what would happen if I did run my car with this block, would it create a hot spot and blow at that spot only damaging piston #1? Also this is an f54 block and I plan to run about 15psi and in the long run 20psi of boost. I know its the smart/right thing to replace it, maybe I can pray to the z gods to bless my block? Plus no one got back to me about those ARP main studs torque spec.

 

Also forgot to add thanks for everyones input, its been very helpful!

[RB26powered74zcar]

I would just take that block in to a auto machine shop and have it properly honed.

 

I haven't seen any thing mentioned on what you are doing, or have done as far as this build goes...

Are you re using same pistons? Is block stock bore? etc.

Please give us something to work from here....

[cholag]

Alright I have a 1983 280zxt and my build is almost done the main parts to this car are:

 

1.NOS pistons from black dragon, size is standard.

2.New bearings and all new fel-pro seal.

3.Reground cam and rocker arms from delta cam.

4.cylinder head has new valve springs and seals plus a 3 angle valve grind and pressure testing.

5.Inter cooler is 24x12x3.

6.Turbo is a Holset HX35W.

7.440cc supra injectors.

8.N42 intake.

9.60mm TB.

10.ARP head and main studs plus rod bolts.

 

So far, I have everything mentioned above and I will now start a list of what I don't have:

 

1.BOV is unknown

2.Will use stock waste gate, if it doesn't work then I don't know what will be used for an external one.

3.Megasquirt

4.Pallnet fuel rail

5.Summit racing fuel pump

 

I believe thats all of it, but with this build I am hoping to put down at least 275hp or at the most 300hp to the wheels. Also I will be pushing 15 to 20psi of boost.

 

Does that sound like a pretty sturdy build to all of you guys?

[RB26powered74zcar]

Now what you need to do is see if BD will exchange those pistons for the next size up oversize, and your block should be honed to that size. I think thats your best solution to the freeze plug screw up. You must have layed into that punch to do that to a stock bore block.

 

Maybe others can change my mind, but I think you'll be ok using it if you go one size up...

[cholag]

Well I was thinking about getting it bored out, but wouldn't that just make it closer to the problem? In my head I think the only solution is to get it re-sleeved and I think that would cost more then getting a junk yard block. But it will be quicker, I am going to go to several shops Monday morning and show them my block to see what they say.

 

I rehoned the block today and here is a close shot and a farther shot, it looks a lot better but still not fixed.

[RB26powered74zcar]

How about a close up from the opposite side, where you used the punch.

[cholag]

You asked and shall receive, sorry thats the best my camera phone can do at night.

[RB26powered74zcar]

So thats the very front of the block huh? I was expecting to see it from the side for some reason...

 

The side plugs I believe, are further from the liners than the front plug is.

 

What happen, you just starting smacking it thinking it must move quite abit, but instead, it was up against the liner almost instantly, but you didn't think it was, so you figured I'll get that sucker to move... one way or another...lol

 

Please don't get mad... I'm just picking at you. I can definitely see myself doing that...

[cholag]

Hahaha no I am not mad at all man, this is just another lessoned learned in the school of hard knocks. I have done some other stupid stuff but you live and you learn and I am not mad or sad. The only thing is, I don't want to pull that dang turbo motor out of the junk yard, thats the only thing I don't want to do! But yeah, the side ones were easy and they are in the middle of the liners so they go in deeper because they are not right behind the walls. I did call a guy that is a cert. mechanic and he said to scrap it because as soon as a run that motor hard its just going to get worse because I ruined the structural integrity of the wall. And thats what I thought he was going to say.

[naviathan]

Ok I understand the damage now. See I read the "How to Rebuild" and "How to Build Performance" L Series books before I started to knock casting plugs out. It warns in one or probably both of the books to be careful on the front plugs as they're very close to the cylinder walls. Funny, I actually read those books but haven't picked up a regular book in years.

[cholag]

Yeah, after I saw the damage I did to the front one I just left the rear for the machine shop that was going to hot tank the block and they got both out. But just to be clear everyone agrees I get a new block or do you think I can still save this?

[naviathan]

The impact marks are just the surface of the damage. Inside the cast could be hundreds of stress cracks from each point. I wouldn't replace the block just yet, but I would get it sonic tested to ensure there isn't anything you can't see damaged. Others might disagree, but I wouldn't throw away a block without being sure.