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-   -   Bad hole (http://www.buggymasters.com/forum/showthread.php?t=4524)

2SlickNick 10-02-2013 03:56 PM

Bad hole
 
1 Attachment(s)
Too sad now, I ruined it. I will post a picture because my words will come out in CAPS!
Am I screwed? What should I do? Stupid me...
Bad spark plug.....
Is this a good time to remove engine tear it apart rebuild it and get to know her??

2SlickNick 10-02-2013 05:17 PM

I guess I over tightened or cross threaded the plug. Now it just spins in the hole. Still starts and runs though.

x-bird 10-02-2013 06:43 PM

If you've been doing jetting changes while the engine is hot, it'll kill the threads if you're not ultra careful.
I ALWAYS use a liberal amount of anti seize on the plug threads.

repair procedure.
A. shop vac the hell out of it
B. rotate piston to TDC
C. stick a rolled paper towel into the hole
D. maybe B -1/2 get a long thin pair of needle nose pliers (electrical type) to pull paper towel out if need be.
E. Install a helicoil sparkplug thread repair insert for your size plug. will require a drill and tap session.
F. Repeat step A then pull the paper towel out and repeat step A again.

Masteryota 10-02-2013 06:52 PM

It won't for long though. You are leaking compression out of that hole every time the piston comes up.

If the hole is stripped out, you have 3 options, replace the head, costly and mostly unnecessary. Remove the head and tap it out to a bigger size, which will require a larger plug, or remove the head and use a heli-coil kit to return it back to its original thread size and pitch.

If it were me, since I have the taps and dies already, I would go a size larger on the hole. For you, it would probably be easier to buy the heli-coil kit, which normally has a couple of stainless inserts, the corresponding tap, and will give you specific instruction and what size drill bit to use. If you use the kit, be sure to put some red thread locker on the insert when you thread it into the hole, last thing you want is the insert backing out when you take the plug out.

Both of the latter can be done with the head installed, but it is not recommended due to shavings and debris entering the combustion chamber.

Here is a thread from here, some opinions back and forth, but I have seen heli-coils purposely run on high compression race engines with aluminum heads without issue. Those guys put them in right out of the box to avoid stripping aluminum holes with all the plug changes and constant rebuilds.

351mustanger 10-02-2013 08:11 PM

You can get a stock head for $30-$60. You will pay close to that for the heli-coil kit. I would just replace the head. If you are going to take it off to drill and tap (I would), you will be replacing gaskets too. A new head and gaskets would set you back no more than $75 and a couple uncomfortable hours sitting backwards in your buggy.

2SlickNick 10-02-2013 08:35 PM

Well guys, thanks for the insight. I am unsure of which
Route I will go.
Half of me wants the heli coil so I can get finish fine tuning carb and jetting, and then be riding again soon. Wife is already upset that we haven't been buggying around.
Other half of me is leaning towards starting an early winter overhaul and upgrade.
After reading about heli coil I am thinking of using them on a new head for constant jetting configuration and plug changes.
Aluminum is weak when hot so might as well use steel heli's.
I would like to go all out and make one bad ass buggy.
We will see.....

351mustanger 10-02-2013 09:10 PM

Heli-coils are not that great. They are a good option when damage occurs, but not something I would put in for good measure. The better choice is a time sert. It has a heftier price tag though. In my opinion, the part you are trying to repair is not worth the time and expense to fix. The aluminum that these heads are made of is very low grade. I would bet over half of the people on this forum, with this type of engine, have been in the same spot you are in now. I would look at it as knowledge and wisdom gained. Replace it and be cautious when replacing spark plugs. Also, the exhaust studs will pull out of the head if you over tighten the acorn nuts that hold the header pipe on. So when you repair or replace the head, don't get carried away tightening the exhaust up.

2SlickNick 10-03-2013 11:15 AM

Okay, I will not use those. You convinced me. I do however think I will go with the 59mm bbk from Tom at syc since I do not have bore it. Also of thinking about going with the larger head too from Tom.
I imagine his heads are better quality than stock.

bear 10-05-2013 09:38 PM

Just do it!
 
As someone who just "split the cases" for the first time, I say go for it, it was alot easier than I thought and there are alot of online videos to help!

2SlickNick 10-05-2013 09:44 PM

I think I will end up going the 58.5 bbk with larger head that way I still get the long stroke, just not ready to splint case yet and bore. I do love bolt ons.

Masteryota 10-05-2013 09:52 PM

Fortunately, the GY6 bolt ons are cheap and easy to install.

bear 10-06-2013 10:17 AM

True, true, but I had to put in a new cam chain, so no choice there! lol

2SlickNick 10-09-2013 02:33 PM

As I tear into this gy6 I gain a new appreciation for this motor and tranny setup. The gy6 is a simple and user friendly motor.
Little adjustments lead to big gains in performance. Very proficient overall design.
Just saying.....

Johnny 5 10-11-2013 10:29 PM

I like to use a plug maybe 3 times and replace it due to the crush washer flattens out. If you use a new plug and are doing a jet run I put anti seize on the threads and only seat the plug lightly and when done doing jet tests I seat the plug and only use a short ratchet to snug it down. The head on my wifes 183c buggy is on the verge of stripping out so I put a new plug in it last spring and am leaving it till its time for a new head.
It is a good idea to let the motor to cool off for 20 minuets or longer before removing the plug.

As for time serts they work but aren't a guarantee but they do work.

2SlickNick 10-31-2013 12:50 PM

I have been saving my lunch money (Cash money the wife gives me from my paycheck:bs2:
I was gonna buy 58.5 BBK, 58.5 large valve head, A12 cam, and cam chain tensioner (since I broke mine like a dumby) all at once, but I decided to buy and install piece by piece.
I am working from bottom up. Just ordered 58.5 BB cylinder sleeve, piston, rings, gaskets, and clips.
I will install that then save more money :bs2: and get valve head next. Oh well....:bigbaby:

SYCARMS 10-31-2013 08:09 PM

Aluminum heads should be torqued. The plug will torque only to 7-10 ft. lbs.. I have removed my plug hundreds of times through the years without incident. Most people tighten the plug way too tight and that is why the threads strip out. Can't tell you how many threads I've repaired on my sons engine. I now have him torque everything until the time he knows the tightness just as well as he knows to breath. I never have used anti seize but I am always pulling the plug but even on customers buggies or whatever I have never had a seized plug.

2SlickNick 10-31-2013 08:19 PM

You are absolutely right.... I should invest in a torque wrench (hence that is why my service manual has torque specs :doh:).
I use to have a large one. do they make smaller ones for tight spaces?

SYCARMS 10-31-2013 08:31 PM

I use mostly a 3/8" drive inch pound wrench.

Masteryota 10-31-2013 08:32 PM

Quote:

Originally Posted by 2SlickNick (Post 37049)
You are absolutely right.... I should invest in a torque wrench (hence that is why my service manual has torque specs :doh:).
I use to have a large one. do they make smaller ones for tight spaces?

Yes. I can not stress how much you need a torque wrench for engine work. The harbor freight wrenches seem to be out of calibration out of the box. I would recommend this tool being one to spend a little on. I picked up an inch-pound wrench from sears for under $50 not long ago.

2SlickNick 11-19-2013 07:52 PM

Well, I have BBK in, 58.5 cylinder head, A-12 cam, and performance coil. Went smoothly except for a few minor bumps in the road.
Bumps :

- Stock intake riser/spacer under manifold; the spacer hole was a little smaller than new larger cylinder head intake hole. - nothing a dremel couldn't handle. That way it actually allows more air in.


- Header pipe bracket holes were 6mm, new cylinder head exhaust studs were 8mm. Nothing a drill press couldn't fix. :biggrin:
Now since I have a larger exhaust port on cylinder head I was wondering if I should attempt to drill out header pipe:dunno::confused: The initial part of the header pipe appears to have a smaller 2" long pipe inserted in it. My thought is should I attempt to use a hole saw bit to open up that initial header pipe? Since it does not really give my larger exhaust port with the still stock header.


- When adjusting valve clearance I stripped adjustment screw head -no biggie, just have to wait on new once to come in.

- Like a :stupid: I accidentally crumbled up cam tensioner gasket :stupid:- new one is on the way.

Now just have to drain oil and get new filter, wait on those odds and ends and hopefully fire it up soon.
I am hoping my largest main jet (134 ) will be good enough , if not then more jetting on the way.

2SlickNick 11-19-2013 10:35 PM

Posts #26-43 http://buggymasters.com/forum/showthread.php?t=4100
I found the answer. Looks like I will not being boring/shaving that header pipe.

x-bird 11-20-2013 06:04 AM

I know this comes too late, but given the thread title, about the best method for hole repairs ... pretty sure KD only makes them for lager SAE automotive sizes.

http://www.ebay.com/itm/10mm-or-14mm...-/290697222898


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