|
Register To Post |
jsup | Why I do my own work........ | ||
Elite Guru
|
I purchased a Super Ram from a very nice fellow on the forum.
I have been working on my motor for some time. The intake is one of the last pieces to put on. SO.......I go to install the intake, I slather a thin layer of sealant on each side of the gasket between the runner and the manifold base. Well, I go to start putting the bolts in and tightening down. The bolts start OK, but I get part of the way in and the bolts start binding. Something's wrong... did I cross thread it or something? So, I take the bolts out and the runners off... I called Accel to see what the spec was on the bolts. The bolts are supposed to be 8MM. The bolts that were shoved in there were 5/16 The idiot who was working on the car (not the forum member but a so-called "professional") cranked down the WRONG BOLTS into the holes. After fking with it for a while I figured I'd have to take the manifold off and take it to a machine shop. So I said WTF. I took a 5/16s tap and ran it in and out of the holes and opened the 8MM up to 5/16s. Now I am going to get all new bolts. I bet almost anything that the person I bought it from could NOT get the car running right as there is no way in HELL it was ever going to seal using those bolts. The forum member I purchased it from went over to a MINI RAM as suggested by the guy who put on the SR (if I remember correctly). This guy was supposed to be some kind of engine specialist. Anyway, it's now going to cost me a wasted $40 for new gaskets, and wasting a week of my time when I could be finishing it up this weekend. How do these hacks stay in business. |
||
Posted on: 2008/1/11 0:24
|
|||
Transfer |
Livin_the_dream | RE:Why I do my own work........ | ||
Senior Guru
|
And the only one you can blame is yourself!
|
||
Posted on: 2008/1/11 0:29
|
|||
Transfer |
CFI-EFI | RE:Why I do my own work........ | ||
Senior Guru
|
Why did you compound the problem by re-tapping the holes to 5/16" when you already knew they were supposed to be 8 mm? It seems you have perpetuated the work of a hack. I wonder what the next guy that gets it, or the guy after him, will say about your work?
RACE ON!!! |
||
Posted on: 2008/1/11 0:50
|
|||
Transfer |
CentralCoaster | RE:Why I do my own work........ | ||
Senior Guru
|
If the holes are already half mangled you can't reduce them back down!
I would've done the same. |
||
Posted on: 2008/1/11 0:53
|
|||
_________________
1985 Z51, ZF6 |
|||
Transfer |
CFI-EFI | RE:Why I do my own work........ | ||
Senior Guru
|
I guess you'd have to have been there. The 8 mm tap may have corrected the problem. I don't know if there is a different convention for measuring English thread sizes and metric threads, but 8 mm is larger than 5/16".
"If the holes are already half mangled you can't reduce them back down to 8mm!" Otherwise, what he did was reduce them back down below 8 mm, to 5/16" RACE ON!!! |
||
Posted on: 2008/1/11 1:11
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
Why did you compound the problem by re-tapping the holes to 5/16" when you already knew they were supposed to be 8 mm? It seems you have perpetuated the work of a hack. I wonder what the next guy that gets it, or the guy after him, will say about your work? Here's why. The starter threads were completely beat up pretty good. They were forced to 5/16. For me to try to cut them back to 8MM would have screwed them up more since I couldn't get them started correctly. 5/16s is .3125 8MM is .314. There is very very little difference. We're talking .002 inches. I chose 5/16 because EVERY SINGLE OTHER HOLE ON THE DAM MANIFOLD is SAE, not metric. Why Accel would use metric in this one case, make no sense to me. Also, I had the dam tap. It works, it fits, the threads are new and clean. The bolts fit snugly, it's not an issue. Why do you have an issue with it? Again we're talking .002 inches. I was ready to take the manifold off and bring it to a machine shop to do it "right". I used the 5/16. If it worked I'm home free. If it didn't no harm no foul. It wasn't going to get any worse. Why would it matter anyway? It's the bolts that hold the runners to the manifold....this application it makes no difference. |
||
Posted on: 2008/1/11 1:13
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
If the holes are already half mangled you can't reduce them back down to 8mm! That's pretty much it. There's no problem with 5/16 |
||
Posted on: 2008/1/11 1:14
|
|||
Transfer |
CFI-EFI | RE:Why I do my own work........ | ||
Senior Guru
|
Wow! Who peed in your Cheerios?
Quote: The starter threads were completely beat to shit. They were forced to 5/16. For me to try to cut them back to 8MM would have fucked them up. Quote: Why do you have an issue with it? Again we're talking .002 inches. Quote: Why would it matter anyway? It's the bolts that hold the runners to the manifold....this application it makes no difference. RACE ON!!! |
||
Posted on: 2008/1/11 1:51
|
|||
Transfer |
red_johnny | RE:Why I do my own work........ | ||
On Sabbatical
|
CHill out everyone, damn. You all are starting a pissing war. Dont make me pull this thread over
|
||
Posted on: 2008/1/11 2:05
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
CHill out everyone, damn. You all are starting a pissing war. Dont make me pull this thread over Ahhh CFI was right, I edited my language. Sorry guys.. |
||
Posted on: 2008/1/11 2:07
|
|||
Transfer |
red_johnny | RE:Why I do my own work........ | ||
On Sabbatical
|
Quote:
Quote: |
||
Posted on: 2008/1/11 2:14
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
Quote: FWIW, I saw nothing wrong with CFI's response. It's just banter. No harm, no foul... |
||
Posted on: 2008/1/11 2:15
|
|||
Transfer |
red_johnny | RE:Why I do my own work........ | ||
On Sabbatical
|
Cool beans then, I just wanted to stop anything before it got carried away....guess I am the one who got carried away
|
||
Posted on: 2008/1/11 2:18
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
I think they're going to say "boy whoever did this is a genius. It's a work of art the way this is put together. Look at those straight, well cut, clean threads. If only the factory could get it that clean!!!" :tongue: :thumbright: |
||
Posted on: 2008/1/11 2:21
|
|||
Transfer |
biggrizzly | RE:Why I do my own work........ | ||
2011 Memorial Day Car Show Winner!
|
pewter99 and IrishMack here,
You guys cut it and play nice or your banned!!! |
||
Posted on: 2008/1/11 4:13
|
|||
_________________
Don Haller Corvette Club of America 94Coupe, 383Stroka, PeteK Trans, 3000stall, 3.54rear, Konis and bigger sways. |
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
pewter99 and IrishMack here, He's just breaking in the new "mod" badge..... |
||
Posted on: 2008/1/11 4:15
|
|||
Transfer |
bogus | RE:Why I do my own work........ | ||
Grand Imperial Pooh-Bah
|
it makes me wonder... why would the mechanic go out of his way to use 5/16" bolts when 8mm should have been included??? In other words, it would not have surprised me if Accel included the wrong bolts.
I would have tapped them to the 5/16"... if for no other reason than to standardize all those bolts to standard measure. |
||
Posted on: 2008/1/11 4:37
|
|||
Transfer |
Notorious | RE:Why I do my own work........ | ||
Elite Guru
|
The bottom line is that it worked out, and for that I'm pleased for the OP. But changing the thread pitch from metric to 5/16 NC could only have done more damage than would have chasing the threads back to what they were already cut to. The two sizes are virtually identical as far as diameter goes, as has already been stated here. So making the slight change to the pitch would only remove that much more metal. This makes the bolt fit a bit looser and problems more likely in the future.
|
||
Posted on: 2008/1/11 5:17
|
|||
Transfer |
C4luva | RE:Why I do my own work........ | ||
Guru Newb
|
Metric bolts on an a/f car yep that makes sense! Wot were the genius,s thinking. I,d be PO,D to.
|
||
Posted on: 2008/1/11 6:27
|
|||
_________________
Red 84 Z51 4+3 With issues |
|||
Transfer |
bogus | RE:Why I do my own work........ | ||
Grand Imperial Pooh-Bah
|
that is a real concern... however, a touch of threadlock or even RTV would solve that problem... and I would coat those threads in RTV... just because.
|
||
Posted on: 2008/1/11 7:01
|
|||
Transfer |
C4luva | RE:Why I do my own work........ | ||
Guru Newb
|
[quote="bogus"]that is a real concern... however, a touch of threadlock or even RTV would solve that problem... and I would coat those threads in RTV... just because.
Not sure I,d do that mate cause I,d hate for them to lock up before they torqued up. Since they,re blind holes. If the threads are fine now they should be all good.. Just an observation. |
||
Posted on: 2008/1/11 7:17
|
|||
_________________
Red 84 Z51 4+3 With issues |
|||
Transfer |
CasetheCorvetteman | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
Metric bolts on an a/f car yep that makes sense! Wot were the genius,s thinking. I,d be PO,D to. Alot of the fasteners on C4s are metric. |
||
Posted on: 2008/1/11 7:40
|
|||
Transfer |
C4luva | RE:Why I do my own work........ | ||
Guru Newb
|
NO WAY!! Are u yanks going GAY! OOPS gone GAY that was 20 yrs ago! Say it isn,t so!! R U sure Case I,ve been play,n round in the door of my Z51 an it,s all A/F??
|
||
Posted on: 2008/1/11 7:45
|
|||
_________________
Red 84 Z51 4+3 With issues |
|||
Transfer |
CasetheCorvetteman | RE:Why I do my own work........ | ||
Elite Guru
|
Some will be, some will be metric. Mix of both on a C4.
|
||
Posted on: 2008/1/11 8:11
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
The bottom line is that it worked out, and for that I'm pleased for the OP. But changing the thread pitch from metric to 5/16 NC could only have done more damage than would have chasing the threads back to what they were already cut to. The two sizes are virtually identical as far as diameter goes, as has already been stated here. So making the slight change to the pitch would only remove that much more metal. This makes the bolt fit a bit looser and problems more likely in the future. I would have gone to the store and picked up a 8MM thread if I had to. The issue is that the first few threads, and about 1/2 way down, were chewed up. There was no material there to get back to 8MM they were already destroyed. Since the first few threads were forced SAE, I went with SAE. I don't care what the measurement was, I just wanted them to work. I'm going to put some RTV on the threads and that should solve that. This application is one of torque, so it will torque down the way it is. |
||
Posted on: 2008/1/11 13:59
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
it makes me wonder... why would the mechanic go out of his way to use 5/16" bolts when 8mm should have been included??? In other words, it would not have surprised me if Accel included the wrong bolts. Even if Accel included the wrong bolts, the person doing the install should have figured it out as soon as they tried to tighten them up. No excuse. |
||
Posted on: 2008/1/11 14:00
|
|||
Transfer |
Rex_Ruby | RE:Why I do my own work........ | ||
Senior Guru
|
I would have done the same thing!
I always say I can F it up as good as any mechanic can |
||
Posted on: 2008/1/11 15:38
|
|||
Transfer |
SpectatorRacing | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
As long as you can get the specified torque on the bolts they should not loosen. Thread sealer may help with leaks, but will not maintain torque over time. Are the bolts torque to yield? That will make a huge difference. Personally, I'd have just used some JB Weld and skipped the bolts altogether :tongue: |
||
Posted on: 2008/1/11 15:38
|
|||
Transfer |
j3studio | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
I always say I can F it up as good as any mechanic can If that's you, what the !@#$% can I say? |
||
Posted on: 2008/1/11 20:10
|
|||
_________________
Grace, 2003 50th Anniversary Convertible |
|||
Transfer |
CentralCoaster | RE:Why I do my own work........ | ||
Senior Guru
|
Quote:
NO WAY!! Are u yanks going GAY! OOPS gone GAY that was 20 yrs ago! Say it isn,t so!! R U sure Case I,ve been play,n round in the door of my Z51 an it,s all A/F?? I've got some metric and standard bolts side by side on my vette, came from the factory that way. The older designed parts, engine block, trans, rear end, rear end, etc, that predate the C4, use standard bolts, everything else is metric. |
||
Posted on: 2008/1/11 21:42
|
|||
_________________
1985 Z51, ZF6 |
|||
Transfer |
Notorious | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
Actually why don't you just put Loctite on them? That'll hold them better than RTV and will still seal them too, if that's a concern. I'd go with the blue, #242 I believe. The red (#271) might be a bit much in this case. It's generally for larger bolts and higher torques. |
||
Posted on: 2008/1/11 23:31
|
|||
Transfer |
CentralCoaster | RE:Why I do my own work........ | ||
Senior Guru
|
Why do need to seal the threads? The bolts aren't a sealing surface if they have gasketing all the way around the hole. You said they're blind holes.
|
||
Posted on: 2008/1/11 23:42
|
|||
_________________
1985 Z51, ZF6 |
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
Quote: That's what I'm going to do. I have the red here, I'll use that. Use what ya got. The red will work fine. Since I tapped them and the holes at 8MM are.002 larger, a little locktite in the threads wouldn't hurt. I just don't want them to come loose. |
||
Posted on: 2008/1/11 23:48
|
|||
Transfer |
Notorious | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
The red will be okay if you don't put too much on. That stuff's pretty aggressive though. I just don't want to see you have problems when it's time to take them loose again. |
||
Posted on: 2008/1/11 23:57
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
Quote: After all this work, and my advanced age (40) I have no desire to ever take it apart agian. I have been particularly anal with the re-assembly. I have learned in the past, that I'd rather do it slow and right NOW than have to do it again. |
||
Posted on: 2008/1/12 2:18
|
|||
Transfer |
Rex_Ruby | RE:Why I do my own work........ | ||
Senior Guru
|
Quote:
Quote: You can say you have me to F it up for you too |
||
Posted on: 2008/1/12 2:47
|
|||
Transfer |
Qack | Actually | ||
Senior Guru
|
Food for thought -- the difference in thread pitch (threads per inch) is the critical item that determines what strength is left in the holes. The holes are definitely weaker by being re-threaded, but the amount the holes are weakened is a function of the difference in thread pitch between the two bolts and less to do with the 0.02 inch difference in diameter.
Think of it this way -- when the holes were originally tapped for 8 mm bolts, a certain amount of metal was removed. Now the holes are re-tapped for 5/16". More metal is removed, now from different parts of the hole wall. Not a good situation. You now put your 5/16" bolt into the hole and torque it. The threads are not supported completely -- if the holes have been weakened enough, the hole wall will fail before you reach the torque specification. That's probably the best thing to happen, as you will now have to bring the unit to a machine shop and have them repair the holes correctly. What is likely to happen is that the hole walls will support the torque spec, but will fail when the engine is under full load. Why? There are gaps where the original 8 mm bolt tap had already removed metal. The RTV, or threadlock or any other additive is not going to increase the ultimate strength of the bolt in the hole. All they do is to resist the bolt from turning. However, when the load is placed on the bolt, it is straight out of the hole, the additives have no affect. This is harder to explain than I thought, and I'd be happy to try again, but the bottom line is that I wouldn't trust your "fix". |
||
Posted on: 2008/1/12 3:46
|
|||
_________________
|
|||
Transfer |
jsup | Re: Actually | ||
Elite Guru
|
Quote:
Food for thought -- the difference in thread pitch (threads per inch) is the critical item that determines what strength is left in the holes. The holes are definitely weaker by being re-threaded, but the amount the holes are weakened is a function of the difference in thread pitch between the two bolts and less to do with the 0.02 inch difference in diameter. I don't disagree with your assessment. My repair is just that, a repair. If it goes badly, I'll take it off and Helicoil the hole. THe threads were so trashed I didn't have much of a choice. I'll admit, it's a shot. Not too much material came out of the hole, I know what you are saying about thread pitch. Essentially, if there isn't enough meat on the threads, the bolt can pull right out. At the point I was at, there wasn't much I can do without complete dis assembly. So I took a shot. If it has to come back off, it's not that big a deal, it's external... We'll see what happens. |
||
Posted on: 2008/1/12 4:01
|
|||
Transfer |
Qack | RE:Why I do my own work........ | ||
Senior Guru
|
Good luck. I hope it works! I have no idea how much of a load the bolts will have to take; here's hoping it's not too much.
|
||
Posted on: 2008/1/12 4:11
|
|||
_________________
|
|||
Transfer |
bogus | Re: Actually | ||
Grand Imperial Pooh-Bah
|
Quote:
Quote: why not drill them out and grow the hole to 9mm or 10mm? Just a thought. I don't know the area and have no idea if there is enough meat left. |
||
Posted on: 2008/1/12 5:30
|
|||
Transfer |
jsup | Re: Actually | ||
Elite Guru
|
Quote:
Quote: Because it's on the car. I don't wan tall those filings flying around that could possibly go into the engine. Tapping the holes was easy as the filings stayed in the oil mix that was on the tap. Drilling would be impossible as I couldn't get the drill perfectly straight and stuff would be flying. YES, I COULD drill nice and slow, but I can't get a drill in there, and a right angle drill isn't easy to control and I can make things worse. It seems OK, it' not holding a whole lot, I think it's going to work fine. I am looking for the spec on these bolts buy I'm expecting no more than 40 FT LBS. All they do is keep the gasket tight between the manifold and the runners. |
||
Posted on: 2008/1/12 13:41
|
|||
Transfer |
Qack | Re: Actually | ||
Senior Guru
|
Quote:
I am looking for the spec on these bolts buy I'm expecting no more than 40 FT LBS. All they do is keep the gasket tight between the manifold and the runners. 40 is too high for 5/16th, even for grade 8. Here's a good table: [url]http://www.engineershandbook.com/Tables/torque.htm[/url] |
||
Posted on: 2008/1/12 15:13
|
|||
_________________
|
|||
Transfer |
jsup | Re: Actually | ||
Elite Guru
|
Quote:
Quote: I have the FSM, I just have to look it up. Like I said, I don't expect it to be much. Based on what I see, I really believe there is plenty of thread. However, I have been wrong before. |
||
Posted on: 2008/1/12 15:20
|
|||
Transfer |
bogus | RE:Why I do my own work........ | ||
Grand Imperial Pooh-Bah
|
40 ft-lb? the intake base uses 25 ft lbs.
I would be it's more like 40 INCH ounces of torque on those... only so as to not tweek things. |
||
Posted on: 2008/1/12 19:51
|
|||
Transfer |
jsup | RE:Why I do my own work........ | ||
Elite Guru
|
Quote:
40 ft-lb? the intake base uses 25 ft lbs. I have to look in the FSM.....but it's not much is the point. I am fairly confident the threads will be fine. |
||
Posted on: 2008/1/12 20:01
|
|||
Transfer |
You can view topic.
You cannot start a new topic.
You cannot reply to posts.
You cannot edit your posts.
You cannot delete your posts.
You cannot add new polls.
You cannot vote in polls.
You cannot attach files to posts.
You cannot post without approval.
|