Broken Head Studs
#61
Racer
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Hi Ian, thanks for the offer and may take you up on it. I agree altarchsa has really been helpful. I am located actually in Grifton NC. So far I have contacted a guy to do the headwork / inspect that is out of Rocky Mount. Once I get the first side done I will do the other side. Its easier on the cash flow this way. I think tomorrow after I get home from work and get a nap in the morning, I will spend some time cleaning parts some more. Hopefully by friday I can have the first set of heads / jugs at the shop to be inspected.
#62
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Good deal, that is not too far away, about 45-60 minutes from me. I am in a pretty intensive masters degree program right now but my weekends are pretty free. If you would like help let me know, I have pretty much all the stuff you will need to time the engine once you get it put back together, metric dial gauge, Z adapter, so you don't need to buy them if haven't already.
Coming from experience, a spare set of hands putting the engine back in is always a good thing. Let me know what I can do.
Cheers,
Ian
Coming from experience, a spare set of hands putting the engine back in is always a good thing. Let me know what I can do.
Cheers,
Ian
#63
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UPDATE: good news is all studs on the driver side of the engine are out as of yesterday. the not so good news is that 2 sets of stud threads are not..ughhhhh!!!! one snapped completely clean and the other just below it snapped leaving a nasty looking shard. I will probably grind that down today to the case so as no one gets snagged by it ( mainly me ). I went ahead and took the other cam tower off because more than likely its gonna go to the machine shop to the snapped stud threads out of the block. ( not comfortable with drilling and easy-outing at this point ). will try and get a pic or two up this afternoon after get out there and clean a few parts more.
#64
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Hey guys, thinking of doing the full rebuild as far as breaking the engine completely down now because of the things in my previous post and also since so far ive only put time into the project. ive got two questions though.
1. is the kit offered at vertex all I need ?
2. instead of having the heads machined and all that jazz..they also offer a reman'ed set..has anyone ever used a set like this ?
one set of heads I have doesnt look good at all concerning the valves so I was pretty much thinking of this route seeing as its also a little bit cheaper than having my heads worked on at this point. Any input will be appreciated.
1. is the kit offered at vertex all I need ?
2. instead of having the heads machined and all that jazz..they also offer a reman'ed set..has anyone ever used a set like this ?
one set of heads I have doesnt look good at all concerning the valves so I was pretty much thinking of this route seeing as its also a little bit cheaper than having my heads worked on at this point. Any input will be appreciated.
#65
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I don't know if you are interested in this at all, but if I were in your place I would send the heads to a Porsche race engine builder ( Geoffery Ring or Steve Weiner comes to mind) and have them ported and 993 valves installed, then put it back together with matching cams.
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#66
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That kit looks like it should work. Most guys will say to forgo the OEM rod bolts and go with the ARP bolts, but they are a little pricey. I would say that if you are not planning to race it, perhaps occasional track days, then you will be fine. I know that there is a particular way that you have to torque them down so that they stretch in a certain way.......I think that is the only part of the engine I am not comfortable with in torquing down, personally I would have someone who knows what they are doing do it for me.
Sorry for the digression, I would say that kit is fine, as long as there is not damage to the pistons, and you say you are getting the heads machined, so you should be good.
+1 on the porting though.
Cheers
Ian
Sorry for the digression, I would say that kit is fine, as long as there is not damage to the pistons, and you say you are getting the heads machined, so you should be good.
+1 on the porting though.
Cheers
Ian
#67
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Torquing the head stud nuts is not that tricky. You just have to determine which of the two stud types you have. First, set the studs in thread locker to the correct height in the case.
Torquing is a two step process. First is to tighten to a torque setting in the prescribed sequence, then an additional 90 =/-2 degrees (IIRC) in the second step. Procedure is well described in both the workshop manual and the 964 Specifications Guide. If you have a good torque wrench you can easily do it.
If you didn't find any corrosion on the broken studs, I'll bet they broke because someone did not follow the prescribed tightening procedure and got a few too tight.
Torquing is a two step process. First is to tighten to a torque setting in the prescribed sequence, then an additional 90 =/-2 degrees (IIRC) in the second step. Procedure is well described in both the workshop manual and the 964 Specifications Guide. If you have a good torque wrench you can easily do it.
If you didn't find any corrosion on the broken studs, I'll bet they broke because someone did not follow the prescribed tightening procedure and got a few too tight.
#69
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Thanks guys for all the input. CRG53..thanks also for yours and maybe when I get some time behind the wheel I will look into doing what you said for now though, since I havent even driven the car very much I just want to get it on the road. Right now, since im gonna be doing so much other repair, just want to keep the cost down as my initial investment of buying hasnt even been enjoyed. I will be working on the passenger side studs wed/thu. as those are the days im off. Oil was caked all over the heads / cylinders/ and pretty much everything so im thinking studs and clean clean clean. so thats my plan for this week....
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#70
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altarchsa is correct, torquing down the headstuds is pretty straight forward (I was talking about the rod bolts in my prior post, sorry, just had to defend myself
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I fondly remember cleaning every part when I did my reseal![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
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I fondly remember cleaning every part when I did my reseal
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#71
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I think the smart thing to do is to buy new bolts and nuts as recommended. However, I couldn't believe that when I mentioned this to one the most highly respected repair shops in the Southwest, they said they re-used the ones that came out of the motor if they were sure they had not already been re-used before.
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#73
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#74
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ughhhhhh im gonna have to replace the flywheel bolts too ????
just kidding thats not gonna be as bad me thinks. at a stop for now as I killed my buddys matco stud puller so I have some kokens on the way. I also ordered the flywheel lock altarchsa...everythings tight on this one. plus with the weather here in nc being 14 deg. this morning...well lets say the kero heater in the shop takes a few to heat up and 14 deg is 14 deg.
still debating getting a welder and doing the nuts thing along with a few other things. so thats where i am right now guys. will update when that comes around again...and thanks agian for all the inputs.
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#75
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ughhhhhh im gonna have to replace the flywheel bolts too ????
just kidding thats not gonna be as bad me thinks. at a stop for now as I killed my buddys matco stud puller so I have some kokens on the way. I also ordered the flywheel lock altarchsa...everythings tight on this one. plus with the weather here in nc being 14 deg. this morning...well lets say the kero heater in the shop takes a few to heat up and 14 deg is 14 deg.
still debating getting a welder and doing the nuts thing along with a few other things. so thats where i am right now guys. will update when that comes around again...and thanks agian for all the inputs.
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Since you didn't know about the flywheel bolts, be advised to also replace the trans pilot bearing in the flywheel - cheap ($10+/-). Also check the bushings on the ends of the shaft of the throwout (release) bearing fork for the clutch. The needle bearings on the ends of the shaft don't wear out too quickly I don't think, but they are "cheap", so I would replace them. The bushings in the transmission that the needle bearings ride in should definitely be replaced.
If they're not in your gasket set (mine didn't come with them), get new seals for the grooves on each end of the rocker shafts. Another "$ouch$" for something that looks so simple. You might also consider new shafts if they're worn, and 'pinch' bolts/nuts for the shafts.
You might want to replacing the two O-ring seals in the end of the trans where it bolts up to the engine.
All the recommendations for replacement parts are in the workshop manuals. If you don't have a copy, PM me.
Any other advice re: recommended/suggested replacement parts..................anyone?