Reusing head bolts, it's not moving - help. Dodge/Mitshibi

|I had the head resurfaced with valves, and bolt seats polished and |more. I scrap, clean the block's surface and threads with carb |cleaners, (and use correctly fit tap) But one things is left out. I |am reusing the non-stretch type head bolts and washers. | |I clean then coat synthetic oil to the bolt threads and washers |according to a Dodge service manual. One of the bolts (center of |the block) refuses to turn smoothly at 60-72 lb. It will turn-stops, |turn-stops, turn, stops... The readings on my beam-type torque |wrench is sporadic and I don't know what is what. I retorque |it again and again, fearing the bolt will just snap off. Should I be |able to undo all the head bolts, replace and clean the faulty bolt |and retorque again? How would you do this differently? | |TIA, Tibur Waltson |[Mitsubishi/Dodge Eclipse `94, 1.8 lt.. Head torque: 30-50-72 lb. ] |[Gasket: Genuine, copper color, with surface resembling epoxy.] |[Previous gasket: Silver in color, with surface resembling aluminium foil. | No overheat, no problems, just improving the head.]

There is some metal shaving or metal burr left in that tapped hole that needs to be removed. Run the tap through it once again and clean it out with highly compressed air. Reinspect with flashlight and magnifying glass.

Lg

You should've tested them before you stuck the head back on, especially if you used a cleaning tap. You could have a slightly bent bolt (unlikely), a twisted bolt (it doesn't take much to screw up a good thread pattern), damaged threads, burrs in the hole, dirt in the hole. Now you'll have to back out all the bolts in the proper sequence, run a different bolt down the hole after you inspect it. Run a die over your suspect bolt. If it cuts one side of the threads then the other as it goes the length, it's twisted, I wouldn't trust it. It'll always (even after a die run) "stick". You apply force, the threads don't quite match up and sticks, you "untwist" some by force, it finally allows the threads to slide releasing some of your applied tension, and goes back to twisted/not matched/sticking again.

|I had the head resurfaced with valves, and bolt seats polished and |more. I scrap, clean the block's surface and threads with carb |cleaners, (and use correctly fit tap) But one things is left out. I |am reusing the non-stretch type head bolts and washers. | |I clean then coat synthetic oil to the bolt threads and washers |according to a Dodge service manual. One of the bolts (center of |the block) refuses to turn smoothly at 60-72 lb. It will turn-stops, |turn-stops, turn, stops... The readings on my beam-type torque |wrench is sporadic and I don't know what is what. I retorque |it again and again, fearing the bolt will just snap off. Should I be |able to undo all the head bolts, replace and clean the faulty bolt |and retorque again? How would you do this differently? | | Make sure there is no liquid left in the hold Rex in Fort Worth

Stop! You probably spent a few hundred dollars resurfacing the head, spend the few dollars and GET NEW bolts. You would be stupid risking using old bolts, that may have stretched not visible to the naked eye. Even a slight distortion will cause binding when you go to torque it.

1) Are you doing the bolts up in the correct sequence? You should be tightening the ones in the centre of the block first and then working your way diagonally to the outside. 2) If you have put too much oil on the bolts you may have hydraulic lock in the block thread. A very light coat of oil is all that is needed and then shake any excess off. 3) Try another bolt in that hole after cleaning the block thread out again. If the same occurs it's a fault in the block thread and if not it's a fault in the bolt.

Dave Baker - Puma Race Engines

I'm not at all sure why women like men. We're argumentative, childish, unsociable and extremely unappealing naked. I'm quite grateful they do though.

Wow. Very appreciated, everyone. I took them into use today.

To answer some questions;

Yes, I put just enough oil on the bolts Yes, I did the bolts up in the correct sequence. Yes, two of 10 bolts found twisted and rejected, but they turn fine. Yes, there`s no liquid left in the hold, probe using a long tooth pick.

Sorry, did not have time to special order new bolts, 3 weeks is too long. Sorry, forgot to bring my die and compressed air tank, which is a good idea.

I ran the tap down three or four times with solvents and see no more debris with a magnifying glass, I then clean out any liquid using a sucking tube. I measure a few bolts for length and width for stretch using a digital caliper, there were none. I use another bolt, still sticks, then I use another, still sticks but performed only 1% better. But I'm out of time, I will use it.

I'm concerned with releasing zero pressure on the head gasket (with the correct sequence) and with the oil, which were lingering around, absorbing between the block and the gasket and ruin the seal within the 30 min standing time. I've done previous head work and release up to zero gasket pressure and it leaks 700 miles later. Would retorque it after 500 miles solve it? Retorquing is simply loosen a quarter turn and torque it up, is that correct?

Thanks in advance. Tibur

Sorry won't cut the mustard with newer engines that use torque to yield head bolts. Cleaning out the tapped holes is just good practice, following the makers advice is also good pratice. Torque to yield bolts do not need to be retorqued, one of the reasons they are used. You need to review your procedures.

Chas Hurst

Are you sure the bolt is not bottoming out in that hole? Maybe the washer is not thick enough or there was a special washer there. Remove the washer and see if the bolt screws in far enough to leave a smaller gap under its head than the washer thickness.

Dave Baker - Puma Race Engines

I'm not at all sure why women like men. We're argumentative, childish, unsociable and extremely unappealing naked. I'm quite grateful they do though.

I'd been wishing to acquire "torque to yield head bolts", but I'm not sure if it's practical. The service manual does not say that I use new head bolts. I really need the torque to yield head bolts now that my beam type torque wrench is useless because my bolts stick and the readings are useless. The clicker torque wrench is even worse.

Tibur

Good idea. Now, I remembered the service manual for a very similar motor says to use "long bolt" in the center. I ignored this, and did not think it mattered. I didn't even took the time to see whether 2 of ten bolt are long. This is a mistake and could be the solution. Well, the bolts are all in, but I have 10 similar bolts stash away from the same engine. I will measure all of them to see whether I have two long ones.

Yes, the bolt is not bottoming out in that hole. I remove the washer and can screw the bolts all the way down by hand till head seats. Compression now read 190-psi on all four.

Thanks. Tibur

There are no long ones!

Thinking it could be the new motor, I put the old bolts into another old unclean, dirty, overheated 1.8 liter engine block (with head and everything) and torque the two center bolts to 106 pounds. And to my disbelief, the bolt went smoothly. No stopping, sticking, or anything. But, on the other hand, the head bolts on my Mitsubishi sticks. I still don't know why it's doing this.

I was merely attempting to twist the bolt's head off at some 160 pounds but I stop short at 106 because being a vegetarian, it's like being hungry all the time. I'm on liver detoxification.

Tibur