Hi Guys! I've got a problem. My 700 Sportsman, equipped with a 800 series exhaust header, has started loosing the outer (2) header (to head) bolts! My theory is that the threads in the head are shot, the bolts screw in OK and bite hard enough to torque to the recommended 17 ft/lbs, but fall out when the head heats up. I've tried loctite blue without good results. I'd like to try an epoxy type thread repair system, the torque isn't great etc....but the suff is only rated to 300 degrees (F).

So I guess my question is: What sort of temps occur in the exhaust manifold bolt area, in the aluminum water-cooled head?

I live in a very remote area a LOOONG way from a dealer. I'd prefer an in-frame repair solution, for obvious reasons.

Thanks,
TB

 

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Nobody? Nothing? Hey guys, I know I'm a newbie to this forum but please talk to me anyway [img]i/expressions/face-icon-small-happy.gif[/img]

 

If threads are wallowed out,TIMESERTS are the best way I've found,but a little more involved than a helicoil which is my second recomendation. On timeserts you have the bits similar to helicoil kits but also have a chamfering bit which allows flush installation and insert a lot easier to install than a helicoil and stronger. Have had same problem you are describing and even our highest strength Wurth thread lock doesnt work. Kits arent cheap,may be cheaper to let a machine shop or dealer install. Just check prices on kits. Good luck

 

Thanks for the reply.

Hmmm, what about tapping it out a size larger, or using a size larger self tapping bolt? The nearest machine shop is too far away (and I don't want to remove the head if possible), and even farther away is the dealer - who really sells tractors and only carries a few parts, I've never seen an ATV there for repair. PLUS, if their parts prices are an indicator of their service prices - I can't afford it.

 

Basically thats what your doing with a timesert or helicoil and the insert reduces back to stock bolt size, BUT the main thing is to be careful on going too deep around head port area. ITS POSSIBLE to tap out oversize,I just havent tried that. Good luck

 

The same thing happened to my 700. What was happening when you gas-it the tourqe twists the engine.... and the front stock exhaust mount limits the pipe from twisting thus making the bolts loosen-up or in my case.....all the bolts fall completly out 7 miles in the woods ......I removed the stock mount and hav`nt had a problem since

 

Thanks!

Hey Rigginguy, I already removed the stock front mount as I couldn't get the header to fit otherwise. However I will look for anything else that might restrict it's movement. How did you repair your head threads, or was any repair necessary?

Thanks,
TB

 

Mine set up is the same 700 with 800 header. I had them in 2 quads mine and my wifes. My came out twice and I helicoil them back in. Hers has only backed out once but did not need helicoil's pit in. I noticed when mine come out I am usally stcuk in the mud and I am cranking the wheels right and left. I have have 27" zilla's and 26" xtr I run on mine and they are hitting the exaust when I turn hard to the right. Back to me saying they come out when I am tring to get out from being stuck. They rub on both quads but I work harder to get out of the hole then she does and I think thats where they are getting strip out.

Is anyone else's header rub the right tire?

 

I'm running 26" Razr 4speed radials and they don't rub. No mud here (yet) this time of year either. We use the ATVs for transportation downriver to town when the river is too shallow for the boat, so we do run them hard and fast. It does rub however on the corner of the right foot well, and I couldn't find a place for the spring they show replacing the previously mentioned front mount. The mail plane delivered the thread repair stuff, and another set of bolts yesterday so I'm going to attempt the repair that way before I go on to plan C.

Thanks,
TB

 

What i did was drill out the stud holes(engine still in frame) to the next size up and put in bigger studs with J-B weld haven`t had a problem since.....