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Fiat Punto Head Bolts Tightening on new gasket

I have a question about head bolts.

......Angle tightening 10 head bolts at stage 3, 90 degrees.

All the bolts have been through stage 1 which is torque at 22/30, then stage

2 which is 90 then meant to go through aother 90 at stage3.

Well some were a bit stiff even though bolts were oiled so I was hesitant and made not of them. Namely central lower head bolt (awkward one mostly obstructed by wire in the head and narrower bolt area) and the far right lower bolt. All the others were relatively ok to turn easy.

I dont know precisely what angles I did those two bolts but they've been through stage 2 and say maybe 30-40 degress of stage 3 instead of the full

  2. I have two choices, loosening the bolts (all of them or just the specific ones?) or loosen off all the head bolts in sequence and do it all again which is safer. I could also use light grease supplied instead of oil, as I didnt notice the sachet until AFTER the bolts were in, but I'd have to remove the head bolts bearing in mind I've already re-attached the inlet and exhaust ports. Typical eh.

WHAT do I do ??? Any advice much appreciated.

Tone

Reply to
Tone
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remove all the bolts, get a set of new bolts, oil or lube them as recommended, tighten them as per recommendations, leave the gasket in place, don' move the engine while the bolts are out and probably the gasket will be ok

mrcheerful

Reply to
mrcheerful

Agreed mrcheeful, it shouldnt move as they are located on dowels.

Just that I was told I could probably get away with it even though you usually should replace the bolts, from the automotive place where I had skimmed. If its absolutely necessary though I will buy another set.

Thanks

Tony

Reply to
Tone

Its much more important that the threads in the block are clean, and the bottoms of the threads are free from gunk and oil. If not the bolts will hydraulic lock on the oil in the bottom of the threads and your torque wrench / dial guage will indicate full torque but they're actually still loose.

Tim..

Reply to
Tim (Remove NOSPAM.

Its a bit late for me to action that now Tim as I did it lunchtime before I read the thread, but thats very helpful and I will bear it in mind if I have to do it again. It was a 3 stage torque, starting with low torque and then finally two 90 degree turns. They seem tight all round (mind you I agree the effort to tighten was not uniform and most were quiet easy but the first bolt especially was quite awkward. but that may because you are starting from the centre and working outwards and the first one is bound to be the hardest to get to recommended torque on last stage).

Wouldnt Fiat be better doing it to multi-stage with torque settings on each. That might eliminate these discrepancies you might get because of oil on low torque? It wouldnt matter about losing note of where you were either, so long as they were torqued. This is what my Rover and VW cars have all had when doing gasket changes.

Tony

Reply to
Tone

The holes and threads need to be clean and clear whatever tightening method is used, including blowing out debris and oil. Stretch bolts are used to reduce maintenance issues (retightening after initial warmup) The trick with remembering where you are is to torque them all (and recheck) then paint a mark on the front face of all bolts, then the marks show whether you have forgotten one, during the angle tightening stages.

mrcheerful

Reply to
mrcheerful

whats the worst that will happen if there is any oil and it sucks itback into the head by the way? I ask because I have angle tightened them now and have two choices- re do it alltogether (only £10 for new head bolts IF necessary then mopping the block), or leave it to chance with me having tightened em all up. Given that its mostly disembled and I could do it now, that would be better than doing it again in 5k miles.

But .....if theres a strong chance I'll get away with it (but watch out next time) then I will prefer to. As gifriend is peed off enough with me about car (more about me going on about it) and i just want to get it finished asap, like early this weekend.

Tone

Reply to
Tone

You have two chances !!

If the bolts bottom out on oil or crud, then they may not tighten properly, the gasket may blow and the head may warp.

Tightening down on crud or oil can sometimes even split the block. Sometimes the oil gets squidged up the threads and causes the gasket to leak.

You know that the right thing is to clean the holes and fit new bolts.

mrcheerful

Reply to
mrcheerful

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