I have heard great things but haven't used a Time-Sert so others can chime in on actually using these kits...

For measuring purposes though, you'll need to know the diameter and pitch of the threads. They are likely M8 x 1.?? but you'll want to measure to get the correct pitch and make sure the diameter is in fact 8mm. Any hardware or fastener shop can measure this for you. Or you can get a thread gauge and a caliper (they're both useful to have around).

Luke

 

Just faced the same issue last month when torquing the very last of the 6 bolts, quite worrying time :facepalm:

I used helicoils to repair the damaged thread with success.

The OFHG bolts are Metric 8x1.25
You have to mesure the threaded part of the bolt (8mm) and not the bolt head which indeed is 13mm. 1.25 means that you have 1 full thread every 1,25mm

What I did is buying a 8x1,25 helicoil kit which comes with the correct drill bit, tap, helicoils and inserting tool.
I strongly advise you to go this way and if you are not familiar with helicoil, have a piece of aluminium to practice before drilling and tapping the engine.

This a fairly easy process to do but the thing is that you have only one attempt to get it right

 

Are you saying "advise you to go this way", are you referring to using helicoils? over "time-sert"? Or just referring to the process in general?

Are you satisfied with the results? Did you have experience already with helicoil?

 

They're definitely M8. That generally comes as M8x1.25. So the peak to peak length is 1.25mm if you measure the side of the threads with a ruler in mm.

http://realoem.com/bmw/showparts.do?model=BD53&mospid=47713&btnr=11_2201&hg=11&fg=30

Worst case is you buy a couple thread gauges or bolts off mcmaster-carr to see if they thread in easily.

 

Thank you all for replying!! This is very helpful information!

 

From the hearsay I've read, time-serts are vastly superior to helicoils, but that is generally in the application of head bolts. But IMO time-serts just seem like a higher quality fix that helicoils.

 

I'm pushing for a complete kit, whether you go for helicoil or time-serts, because they include exotic size drill bit and tap that you surely don't have already

Result is as new, they claim that it is even stronger than the original thread.

That was my first thread repair so no experience whatsoever.

One last word this served me to finally go and buy a torque wrench and avoid ending up in the same situation in the future, you might consider doing the same.

 

So both of you were not using a torque wrench?

 

I was actually using a torque wrench when mine just started spinning and spinning (not tightening). My guess is my threads snapped out when I broke the bolt loose on removal. I remember a loud snap but didnt think much of it at the time. Now that I'm thinking about it....I wonder if these two holes were fixed prior to me with helicoils??? I think that is what came out with the bolt in the threads....the helicoil insert.

 

I plead guilty...
I only guess it is the same for HarleyRob, otherwise it is time to get his calibrated

 

Also of concern is if the threads were lubed with that leaked oil, even using a torque wrench could ruin them. Most of a bolt's torque is overcoming friction, so oil reduces that and you get a higher load per amount of torque than you normally would.

 

And now this makes me nervous to do my own without a kit on standby.

 

This. Stripped and broken bolts are the absolute bane of my existence. I have had absolutely zero luck in both situations.

 

If you can fold what came out on the bolt between your fingers, this is just the aluminium thread from the engine.
Helicoil are stainless steel, so it would require a lot of pressure to fold

 

Any chance you can measure the hole depths on the side of the engine? You could do with with a straight section of a hangar and then measure how far it goes into the hole by marking the top.

 

Sorry, not following you. For what purpose?

 

I remember mine being around 17mm deep and becoming narrower at the end

 

I haven't stripped or broken a bolt on my car yet, but the OFHG thread loss would be catastrophic. I would have to rent a car while the timeserts were shipped.

 

Between both cars (mine/sons) this is the first it has happened to me. No Fun!! Luckily, I have a Jeep Cherokee as well.

 

OP, here's PEI330Ci's work for you to take a look at, he has been an inspiration to countless many....

He is adding larger than stock head studs & time-serts for extra clamping force:
http://www.germanboost.com/showthre...php?9788-Technique-Tuning-Stage-quot-PEI330Ci-quot-330i-Turbo-Street-Car/page20



Rob43

 

OK, reading in another post that the dowels (top right and lower left) might keep me from using time sert kit. So, my question is, how important are the dowels? Once the housing is installed and torques, what role does the dowels play? Are they not just for lining up the housing when installing??

 

Also, found this comment in another thread.

I just stripped out the threads in my upper left bolt hole. After doing some measurements and looking closer, the bolt only screws into 1/2 of the available threads in the hole (for the upper left anyhow). I think I'm going to just try and find an inch or so longer bolt and use the deeper 1/2 that still has the threads intact. It should hold the same torque, since it was only using the outer 1/2 before. Much easier than installing inserts...

Thoughts anyone?

 

That's probably okay if you can determine the length of threads you broke.

Can you explain the dowels you're concerned about?

 

The two dowels that line up the housing. If you have replaced the OFHG you know what I'm talking about. A small dowel sticks up off the block in the top right and lower left bolt locations.

 

Looked at some DIY pics. Yeah those do pose a problem.

 

Yeah! Think I'm going to get a longer bolt first and see what that does. I can get the bolt in 60 and 65mm's (current is 55mm). Sure would be nice if there are still some threads further in that hole. If that doesnt work, I guess I'll have to go the helicoil route....assuming the time-sert can't be used b/c of the dowels. This is a PITA!!

 

Time sert is just brand name.
That's basocally a threaded insert. They are stronger than the original aluminum
The air craft industry has been using them for years because aluminum is a soft metal and doesn't bite a bolt as well as steel does. They used them in aluminum engines for head bolt tightening.....they were put in there from the start. It would cost bmw too much to do this......The only function to ever look out for is expansion and contraction of the different metals.....in this case who cares...

Being that aluminum is so soft. I've always had a hard time using a torque wrench on it. If it's a highly accurate very sensitive $400 torque wrench I might use it. I did use one on my ofh gasket......for ten seconds until I remembered that I don't do that. It was stripping Th e housing out or close to it when I quit. After years of experience you can feel these things and with enough torquing you get a sense when things are good enough tight.

A threaded insert glued in with red lock tight......then use thenoriginal bolt.
A stud would be better and stronger. Studs don't typically strip out.....

 

I had the exact same issue.
When I replaced OFHG, torqueing down bolts, one of (11'clock position) bolt just keep spinning and spinning.
Removed the bolt and found thread from block came out with the bolt. lol

Repaired it with Helicoil and it's good ever since.

 

I recently did this project last summer. Time-sert sells an e46 kit with all the inserts bits you need.


http://forum.e46fanatics.com/showthread.php?t=1043464&highlight=

 

If i am doing a head bolt hole, i will use a timesert. Anything, i will use a heilicoil. Timeserts seem to be a little stronger for the Headbolt.

What do you guys think about the dowels? Dont the time-serts sit flush with the surface? Thus, making the dowel an issue on installation? Do the dowels even need to remain? Do they have a purpose other than lining up the housing?

 

If i am doing a head bolt hole, i will use a timesert. Anything, i will use a heilicoil. Timeserts seem to be a little stronger for the Headbolt.

 

dowels remain. time serts are counter sunk to sit flush with the surface.

 

You need the dowels to hold the OFH in place. You need it steady for PS Pump, Alt. And belts.