ausmini
https://www.ausmini.com/forums/

Rookie error, need advice
https://www.ausmini.com/forums/viewtopic.php?f=5&t=95301
Page 1 of 1

Author:  Daniel Butler [ Sat Apr 29, 2017 12:04 pm ]
Post subject:  Rookie error, need advice

Hi guys I've done something pretty dumb.

Removing the welch plugs on a 998cc block I'm about to rebuild and I put a drill into the side of the cylinder. :evil:

It's a 3mm diameter hole about 2.4mm deep into a 5.2mm thick wall.

Do I get a workshop to braze it or chuck it?

To complicate things this cylinder has been sleeved previously. The sleeve is about 1mm thick,, so there isn't much of the original cast iron left there. It is otherwise a very tidy block.

Author:  simon k [ Sat Apr 29, 2017 12:45 pm ]
Post subject:  Re: Rookie error, need advice

WTF were you doing?? you don't need a drill to remove welsh plugs, a tek screw & claw hammer work better

so the bore itself has a 1mm sleeve, then ~1.8mm of cast iron, then your hole? I can't see it causing a problem unless you're going to run massive boost. The only issue I can think of is that it might corrode away and make the hole deeper, in which case your brazing idea would be the go

Author:  Daniel Butler [ Sat Apr 29, 2017 1:19 pm ]
Post subject:  Re: Rookie error, need advice

Yeah I'm furious at myself. I didn't have a tec screw and claw hammer handy. I had a step drill and a slide hammer. I went one step too deep on the drill.

I was hoping not to have to bore out the cylinder as they are in good nick. BUT if any brazing is going to be done then it will almost certainly need a slight bore to remove any thermal distorsion.

Author:  simon k [ Sun Apr 30, 2017 8:27 pm ]
Post subject:  Re: Rookie error, need advice

Daniel Butler wrote:
if any brazing is going to be done then it will almost certainly need a slight bore to remove any thermal distorsion.


a gentle hone should find anything & take it out

Author:  69k1100 [ Wed Jun 14, 2017 10:14 am ]
Post subject:  Re: Rookie error, need advice

First thing I would think of is how far down the Bore?

Will the weakened section of the bore ever be exposed to cylinder pressure? the piston might not actually go down that far.

Author:  drmini in aust [ Wed Jun 14, 2017 11:46 am ]
Post subject:  Re: Rookie error, need advice

I wouldn't be brazing in there. The metal needs to get to red heat for this, it would take heaps of heat, and it's an invitation to crack it.
I would clean around the hole and fill it with Devcon. :)
[edit] Devcon is a filled epoxy. it's pretty strong stuff.

Author:  minimans [ Wed Jun 14, 2017 12:00 pm ]
Post subject:  Re: Rookie error, need advice

If it hasn't gone all way through or touched the sleeve I'd leave it alone or fill it or as suggested with Devcon or one of the metal type epoxys.

Author:  mtsmini [ Sun Sep 10, 2017 7:20 pm ]
Post subject:  Re: Rookie error, need advice

I've got a spare 998 full engine if you want it! But I might be a long way away :)

Author:  frednutz&co [ Sun Sep 10, 2017 7:28 pm ]
Post subject:  Re: Rookie error, need advice

got a couple of spare blocks here

Author:  peterb [ Mon Sep 11, 2017 7:13 am ]
Post subject:  Re: Rookie error, need advice

She'll be right, just put it together and forget about it. I've seen worse with zero affect. I've seen rust holes through bores fixed by sleeving. There could be rust holes bigger and closer to bore wall In yours but you'd have to X-ray the whole block to see them. It's a mini engine not a 1000hp dragster.

Page 1 of 1 All times are UTC + 10 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/