Guys I need to install an helicoil in the deck of my 8BA. While torquing down my head today...the last bolt (of course, it WOULD HAVE to be the last bolt) wouldnt hold torque and I get the feeling the threads are toast. An inspection confirmed it. Whos done one in their deck and do you have any advice/tips? What size drill to drill out the existing threads and what size tap to tap for the helicoil? I know I gotta drill it square so Ill do my best with the hand drill. This is an assembled engine so Id rather not take it to a machine shop. Anyone? Rat
I would use a timesert over a helicoil for a head bolt..timeserts are solid,rather than a spring, and withstand higher torque. We used to use them in porsche motors with high comps. as the studs would pull out of the alloy cases. i think you go up two sizes over stock unlike a helicoil that goes up one, thats testing my alcohol fogged memory though... not having great luck with that motor, hope this is the last of its tests of your faith.
Hey Lo, thats what happens when you play with shit thats been abused for 65 yrs.... Never heard of Timeserts....are they installed the same way? Where do you get em from? On a Sunday ?? Rat
Just backing up what's been said. Did it on a early 24 studder. Used special helicoil tap. Used helicoil insertion tool. drill size is written on the tool. I bolted a spare head on to keep the drill straight, and started the tap through it too, I think. Mart.
Iv successfully done it the way mart said (with head on) three times. I would however look into the other insert. Iv always thought the coils were kinda lame, but they do work. Keeping the drilling and taping square with the deck cant be stressed enough. I have a 40 merc. motor that a previous expert worked on. All 48 are helicoiled and are, well not strait. I had to install the studs and bend each one strait in the car. It was one of the most aggravating time consuming things Iv ever done.
Hey 296, that musta been a real PITA !! To add insult to injury, mines on the engine stand with the head off lol. Shoudnt be too hard a fix....the original threads are almost "gone" musta been corroded and the torque applied killed em !! Rat
noboD, those "time serts" look like the real "cats meeow!" Just had a quick look; but couldn't find any prices. I have a new set of Offy heads - flathead - and it seems like using them in all the spark plug holes would be a good starting point. Then - because the block is bare - I'm tempted to do all the block threads - at least the head stud/bolts - before putting it together. Thanks for the site info!
Dave - you know the old saying, "If you have to ask, you can't afford it" - it almost applies here - those timeserts ain't cheap by any means. The tool is what gets ya, I think....if you were doing them often, it might be worthwhile, but for a one-time shot, dunno. They are good stuff though from what I hear...
Did some more digging. A kit - with the taps and tools - can run $150 +/- for the spark plug thread repair / replacement. Inserts extra. The other - block - tools are similar. They show a detailed "how to" here >>> http://www.timesert.com/html/howtosp.html Just talked to a friend who is in the performance engine building business; he had never heard of this type of thread repair - he has always been a heli coil user - and is going to look more closely at this and maybe HE will invest in the tools. (and of course my finders fee will be to use them to do my engine!)
I learned of Timeserts right here on the HAMB, do a search I'm sure you will find more intelligent conversation then my "duh, I've never used them". They look like the hotlick. I called the Co. have the catelog, just never had a chance to use them. In the case of a headbolt going into the water jacket I think they would be superior to Heli-coils, would still use threadsealer though. The only saving grace with H-Cs is everyone has them. I've also used Kean-serts which use a standard thread, another McMaster-Carr item. Never been a fan of STI taps, don't use them enough to be worthwhile. A 10-32 thread uses a standard 5/16X18 tap, has spikes that you need a special tool to drive down along side of insert after installation with special tool. Another suggestion Rat, buy a new drill bit, they are cheap insurance. If you use a resharpened bit you may wind up with a bigger hole then you want, if the bit is sharpened out of center. I'm even thinking I used a tap handle to turn the drill bit when I did mine, instead of a drill motor. Tell you what, pay my plane fare I'll bring everything I need to do all the headbolts. Ok mate?
I had my machine shop do it because they have much more experience than I. Here's how it came out. You can barely see, but the repairs are between #1 and 2, and between #3 and 4, the holes that are above the water holes. pigpen
Here's a better pic of the repair. The inserts they used are water tight and I think a sealant is used also so as not to get seepage up through the head bolts. pigpen
It wouldnt be the first time a flathead ran just fine with 23 bolts. Go to your friendly industrial fastener company and see if they have a bolt with deeper threads; I forget the actual terminology but hardware comes in several "tolerances".
Did the repair today using an old head and came out very nice. Bolted on the head and torqued it up....all done. Thanx for the tips and info guys !! Rat
Dude who didyou piss off. I can't believe the bad luck you are having. So did you Helicoil or Timesert?
Good info !! Well I did the job using a cyl head as a guide....came out REAL nice. Bolted the head back on and torqued it down with no problem !! I tried the longer bolt trick first, hoping that there were enough threads left in the block to "grab" onto, but no dice. So Helicoil went in and whats even better is that the head bolt sits parallel to the head surface so I musta tapped it straight huh lol. Thanx for the tips !! And Nobod, thatd be one damn pricey Helicoil if you made a service call Down Under haha..... Rat
Haha yeah man Maybe I offended the flathead voodoo gods in some way and this is their way of sayin OHV !! Fat chance..... Rat
This is a great post. When I was prototyping the 24 stud heads 7+yrs ago @ Cook's I decided to use my extremely cool running 34 Ford 3W. engine as the ginea pig. So after taking off & putting on 20 pairs of our heads on it I had become pretty savy about breaking studs,drilling through water jackets,tapping new threads, Mind you,this engine ran prefectly fine when I drove it there. This was the only way Cook's would let me put these heads back out on the market. At the time time I thought that it was a big headache, little did I know that, that experience would come in very handy in the years to come. I have a 77 Chevy Custom Deluxe Short Bed P/U w/a 250ci 6cyl & a 3 on the tree. While I was driving home from Wynns in Brea,CA. One day, I heard this weird sound that I thought was coming from the bell housing area under hard accel. Well it just got louder so while I exited the fwy I listened to it @ the light, It was coming from the Cyl head area, This sucker has the intergrated intake manifold cast into the head, so I thought I burned a hole though the casting. after spending a few hrs in the bone yard, I found a likely replacement already off. Went to go pull off the head, no problem there, but the head gasket was toast! Now a have a spare head, after letting it sit for a couple of months, a friend & I got re-inspired & decided to finish up the job. started torqing down head bolts & what does the last one do? You guessed it=pulls out. but no thread remants are on the bolt, I stick a magnet in the boss, nothing there either So I really started to look @ the boss. It looked like it was over drilled @ the factory-this truck barely had 100k on the clock after 25yrs. I thought,Sh*t, now I'll have ta replace the block. Decided to go to King Bolt in Covina Ca. & get an slightly oversized bolt & Tap, while the guy & I were looking @ the bolts, he asked me if I had ever tried a Time-Sert kit, "I said a What? " Well as a mechanical claims adjuster, we were just beginning get all these claims in with Northstar Cad oil lks & pulling threads out of the cases. Light bulb goes off in the ol vacancy cavity "Ah,yeah I know what those are" I didn't have the kind of coin that they were looking for on me @ the time So the "old" girl friend stepped up & said $85.00, no problem! (somedays she was real cool) But believe me, she got paid back 10 fold. So what I still think was going to be major deal, takes all of about 5-10 mins with the cool lil drill bit,counter sync,tap & the correct size Time-Sert(sold separately @ 2.89 ea.) Man I got the sucker in the block flat on the deck,We're talking far superior to a shitty ol Heli-Coil, those things suck The head has been back on for couple of years, with no additional problems and now I'm a true believer in the ol Time-Sert kit. I wouldn't use anything else Note! (This has not been a paid endorsement for this product. Our company is not responsible for any claims or mis-representations resulting in use of the said product) Hee-hee,hee! Just figured that I'd throw a lil humor in there too!!!! Good luck & I hope Time-Serts work out for you. Kevin
Good post Kev !! I went with the helicoil ...because Im acheap bastad, thats all they had and 55ft/lbs isnt gonna kill a helicoil too fast !! Cheap, fast and NASTY like the Psycho man hisself !! lol Rat
Kevin; Endorsement or not; you got me convinced! One thing that has me curious though; how well do they work in BLIND holes? Or more specifically, the blind head studs/bolts on a flathead. The next question is; where do you buy them from? I spent an hour "surfin' " the dealers and can't find anyone closer to home. (Canada)
Well i don't know who to thank but i just repaired my flattie tonight. Had a stripped out bolt hole. What i did and some one here had this idea. I took a peice of 1" stock 7" long and drilled a hole in the center the size for taping a 1/2" hole, then 2, 7/16" clerance holes to match up to 2 other bolt holes. Used this to drill the hole. Then used a 1" peice of stock and match up the holes but tapped the center hole. Used this for tapping. I made a nes stud with 1/2" on one side and 7/16'on the other. the car is back on the road tonight it worked out great. All this was because i had a broken valve. Thanks again guys.
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