 Pin holes in the head sealing surface..., Can I run as-is, or should they be welded up? |
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| jhadler |
 May 15 2009, 11:21 AM
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Long term tinkerer...  Group: Members Posts: 1,879 Joined: 7-April 03 From: Lyons, CO Member No.: 529  |
Hey all,
The motor is going back together, and upon close inspection of the heads, there are some small pinholes along the sealing surface of the head. I'd like to drop the head gasket and lap the cylinder to the head, but will these holes be a problem? Based on the measurements, the pinholes will be 0.016" outside of the ID of the jug, and as such, covered by the jug. But is that enough? Can I run this as-is? Lap the jugs to the heads, and run sans gasket? Should I run I gasket? Or should I have the holes welded up and re-flycut the heads? There's all of about 40 minutes run time on these heads right now. Thoughts? Experience? Thanks!  -Josh2 |
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| HAM Inc |
May 15 2009, 02:08 PM
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#2
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
QUOTE Would you run with a gasket No gasket. QUOTE or just lap the jug to the head and call it good? You can lap it, but I wouldn't call it good! You probably won't suffer a catastrophic failure, but you may develop a head leak at some point. If the flycut is perfect and the case is perfectly decked then you stand a fighting chance. Otherwise... What is your compression ratio? |
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| jhadler |
May 15 2009, 02:18 PM
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#3
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Long term tinkerer... Group: Members Posts: 1,879 Joined: 7-April 03 From: Lyons, CO Member No.: 529 |
QUOTE(HAM Inc @ May 15 2009, 01:08 PM)  No gasket. Okay. That was what I was hoping to do. QUOTE You can lap it, but I wouldn't call it good! Good enough for a daily driver? Good enough for an autox car? Good enough for the occasional track day? QUOTE You probably won't suffer a catastrophic failure, but you may develop a head leak at some point. Short term? Or long term? I'm not likely to be able to do yet another tear down after this build for quite some time. QUOTE If the flycut is perfect and the case is perfectly decked then you stand a fighting chance. Otherwise... What is your compression ratio? <gulp>. Well, I trust the guy who did the heads. And I believe they're done well. The case has not been decked recently. CR. I haven't crunched all the numbers yet. But 96's on a 2.0L crank, and the heads have all measured out at 64cc's. I suspect it's gonna be at least a full point higher than stock. If you think they'll manage well as is, I'll leave 'em alone. If not, I'll have them fixed. I don't think I can afford to have to do this all over again in a year or two... JB Weld? (IMG:style_emoticons/default/biggrin.gif) -Josh2 |
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Posts in this topic
jhadler Pin holes in the head sealing surface... May 15 2009, 11:21 AM
type47 Are the literally holes all the way through or jus... May 15 2009, 12:11 PM yeahmag You need to fix that. It's the sealing surface... May 15 2009, 12:19 PM HAM Inc Someone welded the ex stud boss that runs under th... May 15 2009, 01:05 PM
jhadler
Someone welded the ex stud boss that runs under t... May 15 2009, 01:28 PM yeahmag Would running a small (thin) copper sealing ring h... May 15 2009, 01:08 PM Mark Henry Len gave you the answer...no gasket.
No gasket.... Jun 30 2009, 07:25 PM HAM Inc If all of the work is otherwise good you'll pr... May 15 2009, 02:30 PM jhadler
If all of the work is otherwise good you'll p... May 15 2009, 02:39 PM Cap'n Krusty WTF is this obsession with JB Weld? NO, it won... May 15 2009, 04:30 PM jhadler Easy Cap'n... My JBWeld comment was in jest...... May 15 2009, 09:50 PM jhadler I spoke with the fellow who did the heads. He reco... May 20 2009, 03:51 PM jhadler :bump:
Everything's going together now, but ... Jun 30 2009, 05:57 PM yeahmag Gaskets on the barrel side are for adjusting CR. Y... Jun 30 2009, 07:07 PM Vacca Rabite Just to be sure you are clear on this. The rings ... Jul 1 2009, 06:12 AM jhadler I'm talking about head gaskets, not the barrel... Jul 1 2009, 10:16 AM ME733 Pin Holes....the most reliable, and cost effictive... Jul 1 2009, 12:24 PM Jake Raby No gaskets.. Adding another expansion factor to th... Jul 1 2009, 12:32 PM jhadler Thanks Jake. Yeah, you're right, it's a bi... Jul 1 2009, 03:28 PM jhadler FYI, the measurements that I have right now are as... Jul 1 2009, 03:37 PM Jake Raby Josh,
I haven't forgotten about you but I don... Jul 1 2009, 03:51 PM jhadler
Josh,
I haven't forgotten about you but I don... Jul 1 2009, 04:52 PM HAM Inc
This head had a pin hole in the same area. Money... Jul 1 2009, 05:14 PM HAM Inc BTW, this head landed on my bench in the past mont... Jul 1 2009, 05:16 PM Jake Raby
BTW, this head landed on my bench in the past mon... Jul 1 2009, 05:45 PM jhadler Well, since the motor is coming out and the heads ... Aug 27 2009, 03:39 PM brant Josh,
please update me
obviously its not a good ... Aug 27 2009, 05:02 PM jhadler
Josh,
please update me
obviously its not a good... Aug 27 2009, 06:05 PM gothspeed If it is a 2.0 head .... replace both of them with... Aug 27 2009, 05:46 PM jhadler
If it is a 2.0 head .... replace both of them wit... Aug 27 2009, 06:03 PM brant How did you decide ?
detonation?
brant Aug 27 2009, 11:10 PM |
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