Know what sucks?

[rustyATV]

Know what sucks?

When you finally, after months of setbacks for various issues, go to torque the head of your first powervalve cylinder, and you get this:

[born2ride14]

Helicoil!

[rustyATV]

I know, I'm just wondering if I can do it cleanly without removing the cylinder. I've already had to waste a few gaskets for a dumb mistake.

[leager-n-ky]

Hey Rusty, I think if you take some masking tape, and cover everything else up on top, I think you will be able to do it with the cyl. still on. Maybe, just thinking out loud.

[rustyATV]

Yeah, I've got that blue painter's tape and was thinking of using that. I'm just worried about how straight I can drill it with a hand drill. I know drill bits are self-aligning in existing holes, and I won't be removing much, but I'm still a little hesitant.

[C41Xracer]

You can do it take your time. You won't be removing much material. I do helicoils at work all the time

[LONG-ROD]

and the dice roll...

[redred55]

What cylinder is that??

[thedeatons]

I would tape down in the cylinder, over the piston to cylinder gap, stuff a sock in it, then tape over the top. Use regualr masking, then QD the cylinder at the end to remove the residue (Quick Dry Electronics Spray Cleaner - Red Can).

DO NOT USE A HELICOIL. Those are for newbies in my opinion. I come from a military background, where everything has to pass shock and vibration tests.... USE A KEENSERT instead. Just like a helicoil, but at the end you tap the two prongs down into the threads, not letting the Keensert come out. These are the strongest thread repair, and perfect for times like this.

I actually used them throughout my clutch cover mounting locations, and the seat tighter than the standard holes.

See here:

http://www.bjg-design.com/designbook/pdfs/INS-KNS-KNS.pdf

You can buy the tool to screw the Keensert in, but really all you need to do is drill the hole out to the spec the Keensert requires, tap it to what the Keensert requires, then screw it down, and use a light tap with a small hammer to seat the tabs. Keenserts can easily be ordered at any Fastenal. Just take the stud with you and have them order the correct Keensert size. Order a few of them, cuz you never know....

[Aceman]

I've used a Helicoil for a drain plug before and it worked well. But like thedeatons said, I've heard a lot people recommend a keensert or timesert, I think it's called, as even a better option.

[CHAR250R]

The Keensert is the way to go. I use them here at work, and they are practically bullet proof. Pull the cylinder off and do it right. All it takes is ONE little piece if metal in the cylinder, and poof, it's wasted. You've come this far, don't skimp because you are in a hurry. Good luck. :)

[rustyATV]

I've actually used one of those inserts before, on my frame.

For this time around I'm going to bring it to a machinist friend at work to have him helicoil it. He'll sneak it on the mill and locate it right.

If I get to where I'm working on this cylinder regularly, I'll consider using those inserts, but for now a helicoil will do.

[rustyATV]

Originally posted by redred55
What cylinder is that??

It's a Duncan

[All250R]

Blows! - what happened anyway?

[rustyATV]

I don't know, must have been boarderline. I threaded it in and snugged it by hand, put on the head and did a light first pass, then went to torque it to 200in-lbs and it just tore the threads up.

[Honda 250r 001]

man that sucks, you dont want to screw it up but you want to get it together. How did it happen? send that back and ***** at them. thats crap! unless you were torquing more than reccommended.

[rustyATV]

This keeps getting better.

The guy doing the helicoil for me calls me over today and shows me where the stud hole breaks into the water jacket, caused by the casting being severely misaligned. He's going to go ahead and helicoil it, but I'm going to have to take a look at it and make a call before I try to use it. If I can get a picture up when it comes back, I'll post it.

[All250R]

Bogus. Can you take it back to who you bought it from?

[Motofool250r]

fill the water jackets n hog that thing out to the max n run n2o till you put a hole in it =)

if it breaks into the water jacket i dont know if id trust much to hold the water in there.

[hondamancbr03]

Originally posted by rustyATV
This keeps getting better.

The guy doing the helicoil for me calls me over today and shows me where the stud hole breaks into the water jacket, caused by the casting being severely misaligned. He's going to go ahead and helicoil it, but I'm going to have to take a look at it and make a call before I try to use it. If I can get a picture up when it comes back, I'll post it.

Weld it!!! We have a couple local shops that have repaired issues such as this, in fact some port guys go so deep in the tranfer ports that they break through the wall and weld it up to get the port angle they desire.....The barrel is not in bad shape, just needs a little TLC.

[Motofool250r]

yea if you can get in there with a welder by all means sometimes it hard to find that quality of welding.

[hondamancbr03]

Originally posted by Motofool250r
yea if you can get in there with a welder by all means sometimes it hard to find that quality of welding.

Don't take it to a normal welding shop, you'll need someone that has experience in port work, they'll have the tools to get down in there to clean up the welds for water flow. We have local shops that you can ship too that are very trust worthy. Let me know if you need some contact numbers. Good luck!

[SuperSherman]

If bench W is anywhere near bench X, I'd say bring it over with a beer and I'll fix it good. Bench X is in Roseburg Oregon, by the way. No joke, easy fix no matter which way you do it.

[regg187]

look at sending it back, if the casting is that mis-aligned what else could be wrong with it? it looks as though QC was not on the ball that day. just tell loren to go f himself and take the POS back and stop selling the trashed ones too. J/K J/K lol don't tell him that you'll be blacklisted!!!!

[hontrx265r]

Just so you know if you helicoil it now you can forget about a timesert later.. they each use their own thread type for the tap.. which are different. The sizing will be wrong when you try to switch there won't be an insert for the 8mm stud.. just fyi

[IcutMetl]

Naa...it'll still be alright. I've fixed muffed up helicoiled threads with key-inserts quite often in the past. The dril is of a larger size yet, even larger than what is normally reccomended for the tap required to create threads for the insert; this is to give room for the keys to form into the leftover threads when you pound them in with the supplied tool.

A company in Cleveland; Jergens, makes such keyed inserts. Used to use them alllll the time for fixing aluminum mold bases, crashed die sets, and similar. I used to machine all the thermoforming plugs for those tapered plastic car cups at Taco Bell, etc, and used key-inserts in all the aluminum bases. They can take quite a bit of abuse.

They're a tad bit more involved than a heli-coil, but not hard to come by; search Jergens on the net, or at MSC, McMaster Carr, Fastenal, etc.

[rustyATV]

I'm out of town for a wedding at the moment, but I'm working on posting a video on Youtube to illustrate the issue. It'll be my first one, so it'll probably suck, but I'm hoping it'll give a better view of things.


And, yeah, the insert threads are MUCH larger than the helicoil threads. The trick will be getting the helicoil out, though that also means the insert will project into the water jacket even more than the hole does now, so fixing the casting is even more important.

[IcutMetl]

Here's a dirty trick to get helicoils out of existing holes. Get yourself a prick punch, ice pick, something long, slender, & pointy. Also a small hammer & good needlenose pliers.

Get that punch along the top most portion of a helicoil thred, right up under the coil, and tap it with the hammer to pry the coil out of the thread...force the punch in, deform the helicoil...it will unravel like a slinky if you do it right. Then, grab hold of it with pliers and pull it straight out. If done right, there'll be no damage. Since you'll have to drill the hole bigger for the key-insert, you should be fine anyways. I would suggest at least drilling it square on a drill press where the drill will follow the hole. You can even start a tap straight with the drill chuck...BY HAND...before using the wrench. If you have access, a bridgeport mill will work wonders, but not neccessary here. I have a small shop I'm getting going; if I had my 3-phase convertor going, I would offer to do it for ya.

As far as water jacket damage; don't know what to tell ya. I'm not an engine guru, but I've repaired a lot of things made of metal.

[rustyATV]

Here's the vid of my jug

http://www.youtube.com/watch?v=3h1bXpCsVwE

[312R1]

Originally posted by rustyATV
Here's the vid of my jug

http://www.youtube.com/watch?v=3h1bXpCsVwE


Have you tried calling Loren Duncan to see what he says? If I was you thats the rought I would take.


-Steve

[rustyATV]

Yeah, I'll probably call him here in a bit, just not expecting a whole lot after the last couple of phone calls.

[hondamancbr03]

Originally posted by 312R1
Have you tried calling Loren Duncan to see what he says? If I was you thats the rought I would take.


-Steve
After watching your video i seen where you were concerned about the width of the water jacket for access to weld the area.....This is not the approach they would take, most welders (at least my machinist) would fill the existing hole and use the head to align and re-drill the new hole.

Good Luck

[86 Quad R]

Originally posted by hondamancbr03
After watching your video i seen where you were concerned about the width of the water jacket for access to weld the area.....This is not the approach they would take, most welders (at least my machinist) would fill the existing hole and use the head to align and re-drill the new hole.

Good Luck


agree'd! thats the approach that any of the machinist i use would take.

[rustyATV]

Originally posted by hondamancbr03
After watching your video i seen where you were concerned about the width of the water jacket for access to weld the area.....This is not the approach they would take, most welders (at least my machinist) would fill the existing hole and use the head to align and re-drill the new hole.

Good Luck

How would they build the material for the threads on the outside of the hole?

The reason this stripped is because the pad (underneath the deck) was so misaligned that the stud hole ended up going right down the side of the pad, putting part of the stud in water, which is why you see light in the hole from the water jacket. Only filling the hold does not solve this. My thought is they would have to greatly over-bore the hole, weld in an aluminum insert, and then start over like you said. But then I'd be concerned about warping with a billet insert sitting in a cast block.

[born2ride14]

I would contact duncan and see if they will do anything

[hondamancbr03]

Originally posted by rustyATV
How would they build the material for the threads on the outside of the hole?

The reason this stripped is because the pad (underneath the deck) was so misaligned that the stud hole ended up going right down the side of the pad, putting part of the stud in water, which is why you see light in the hole from the water jacket. Only filling the hold does not solve this. My thought is they would have to greatly over-bore the hole, weld in an aluminum insert, and then start over like you said. But then I'd be concerned about warping with a billet insert sitting in a cast block.

From what i've seen done, my machinist would most likely over drill the existing hole both wider and deeper prior to welding back to the top of the deck, after that he would start from ground zero and either install a heli-coil (which he prefers) or an insert and there you go....But remember, like anything else there's 10 ways to do it and they all would work. from the repairs i've seen him do, your barrel is an easy fix. Be prepared for the opinions regarding heli-coils vrs. insert vrs. just welding and taping a factory style hole...Everyone has an opinion on which is better, I myself leave it the machinist. Like i said before, if you need a couple numbers of good shops that can do the repair let me know.
I agree......CALL DUNCAN FIRST!!!!!!

[rustyATV]

Yeah, I'll get around to calling them eventually. I just need to get home before 8:00PM one day

[rustyATV]

Quickie update - Got Loren on the phone and he wants me to ship the jug to him to check it out. Said he'd do this for free and let me decide if I want him to do the work once he quotes it.

He actually said he'd do an insert rather than a helicoil, but I don't think he was convinced that the existing hole broke into the water jacket.

More to come later

[Honda 250r 001]

so i take it you got er bolted up? how did it go? what did you have done?

[All250R]

I just watched your vid for the first time. Thinking outside the box, would it be useful to core drill from the outside of the cylinder into the jacket with a big enough access hole to weld through? Then weld the core hole back in and work on the stud hole from there. I've had to think about this porting the early model cylinder where the material between the ex port and the coolant jacket is a little thin. I imagine the other stud holes are in need of similar attention if like you said there was a misalignment with a multipart casting.