Why is my chair tensioner not tensioning ?

Red Loctite would not be any use. As you know it is for locking good threads, the Loctite won't secure the bolt and provide the clamping force between the head and cap and with the constant forces of the cam opening the valve it will just put the excess load on the other bolts securing the cam journal cap or possibly break the cap. Another possibility is tapping a new thread, if that could be done with the head in on. It is a bummer because you nearly had it fixed.

 

Thanks Franz, I thought about the loctite and even if there was thread, it's oily so won't work anyway properly. Tapping a new thread is the same as doing helicoil, might as well do that...I'm trying to sell it like it is... if it doesn't sell this month I'll pull it apart (the head again) and will also put the springs in the right position. I might as well do that anyway, as it's going anywhere. So why not
You've been so good help, practically but also mentally. Thanks man !

 

Tapping a new thread means using a thicker bolt. Using a helicoil allows the same bolt thickness to be used if you use the correct size and there is enough material to take the helicoil insert. Leave it and go back to it. Take a break that's what l do. I fitted a new shock absorber spring on my car and had it all complete. Then remembered l forgot to tighten the bolt on the damper we have all been there. Most times l get it right though .

 

Fitting a threaded insert is a DYI job. But you’ll need to practice drilling a straight hole in wood first.

 

Yes and put tape around the drill bit so you don't drill to deep.

 

Indeed, the thread is still there but not enough to get torqued spec.

I wonder if I could get the torque with a compression washer... Or a longer bolt?

But yes I can do the helicoil. Might as well do it. Might not even need to remove the head if I protest everywhere for shavings

 

Get a tiny tube like the red one you get on a can of WD40 to check how deep the hole is the existing bolt goes into. Threads will probably damaged all the way down. Do the helicoil. Take your bolt to the place you are buying the helicoil kit so you get the right one. The hardest part is drilling square and checking the depth. If you have wood you can practice drilling a few holes as @k-moe suggested. Get the kit because it has everything you need to do the repair.

Longer bolt you can check the depth with the tube above and compare it with your bolt. Compression washer l would not use. Go the helicoil route and you will get the torque you need.

Yes protect it from shavings especially the camshaft tunnel.

 

Right, then helicoil kit it will be. m6 it seems. I have to dbl check. nothing available locally so ill order

 

Yes l am sure it is M6 you can fix it.

 

You can use the cap as a guide to drill out the damaged threads first to help you get it square. But use a cobalt drill. I would use a hand drill just my preference if drilling through the hole in the cap. You don't want that getting cracked.




Has anyone used the cap as a guide to keep the drill bit square?

 

I'd feel more comfortable if he used a spare cam cap as a guide.
Since the threads stripped out instead of the bolt snapping there is no need for a cobalt drill. Regular HSS will do the job just fine.

 

Those are better ideas.

 

Since the original hole is being opened up, wouldn't a light touch with the drill allow the bit to follow the original hole? I would be more worried about tapping at an angle for the helicoil insert

 

Yes just drill once using the drill supplied in the helicoil kit using original hole as the guide. Still better with an old cap to use as a guide.

 

Though using the old cap will only allow cleaning up the original threads. The helicoil needs a larger bore.

 

Thanks guys, the threads are actually further down the hole and the top part is actually slightly larger... Maybe 7mm. So that will be a good guide already for drilling straight. I'm very good with drills and such so shouldnt be a problem. I reopened the head... Put the valve springs already in the right orientation. Only one was wrong haha, quite lucky still.
The gasket is gone though so that's a good waste of 50eu. Damn it.
I have ordered the helicoil kit for m6 since nothing local exists but I am taking a holiday for 3 weeks so back at it end of July.

Thanks

 

The top 7mm approx wide section is where the alignment dowel fits.