How many times can you go through a torque sequence when installing heads? I'm worried I messed up and should try again but don't wanna make it worse

Question

2002 Ford Escape

Cylinders

123

456

Rear Bolt Order (see picture below)

8426

7135

Front Bolt Order

7135

8426

Torque Sequence

1 30 ft lb

2 tighten 90 deg

3 loosen 360 deg

4 30 ft lb

5 turn 90 deg

6 turn 90 deg

My Fears

First, I installed the front head where there rear one goes (it fits when its backwards. i didn't notice). I went through the whole torque sequence. I obviously had to take it off. So for one I had to retorque those bolts which I don't think youre supposed to do. For two there was a little bit of cleaning solvent that got smooshed into the head gasket (I cleaned thoroughly and tried drying but I guess some was still on there). Anyways, at least from installing the head backwards I am afraid some parts of the gasket might have been smooshed in the wrong spot since the bottom of the heads are not perfectly symmetrical. It's a metal gasket though and there were no visible impressions anywhere.

Second, when tightening to 30 ft lbs I did it without a torque wrench first because a torque wrench would take forever. Most of the bolts started at 20ish when I first hit them with the torque wrench but some of them were much closer to 30 or maybe even at 30. So I'm worried I messed up the torque sequence. I think I probably did go through the torque sequence good enough but can't shake the idea that I should do it yet again. That'd be the third time the bolts on the rear head were torqued and the second time the bolts on the front head were torqued.

Third, Haynes just shows the bolt order for the front head. So I didn't know what bolt order to use on the rear head. Should I mirror the bolt order (like I showed above) or go by their absolute position. I guessed it should be mirrored but I'm still uncertain if I did it right.

Thanks for any help you can offer. It was super late when I did this and I probably should have saved it until the morning but I wanted to get it done.

Answer 1

Considering you have torque to yield (T2Y) bolts, once torqued through the angle sequence, you're done. If you remove the bolts, you have to start over with new bolts. T2Y bolts are one and done, meaning one time use. Once stretched, they will not work correctly again and need to be replaced. Conversely, if you put more angle on the last torque (or past the last torque), you are deforming them more than they were designed to, which makes them weaker than they should be. At that point they should be replaced as well.

Sadly, from your description, I'd say you need to start over with fresh head gaskets and head bolts. You cannot repair these parts once used.

When putting things together initially, you don't need a torque wrench. Use a ratchet or what have you and get them evenly snug. Just following the torquing sequence to get them down to snug. This shouldn't get you ANYWHERE near to 30 lb-ft. Once snug, then use the torque wrench in the proper sequence.

Bolt order should be the same for front and back heads.