This 86 Toyota truck 4x4 2.4 EFI is suppossed to have a new engine in it..it now has 1100 or so miles on it..do the head bolts have to be retightened?

While not required, it's a general practice; so yes.

Give the 22R tech tips a look in the archive; just select 'view all' in the lower left of the page to find it.

Thanks kewlynx..nice of you to answer all my questions.

Totally new? Like assembled, tested, and shipped as a crate motor?
Theoretically, it shouldn't.

This is something I've never understood. People often reccomend this.
However, every year millions of cars are built and sold new.
None of them has the owner return 1000 miles later for the head bolts to be retightened.

Yes, I know the manufacturers runs the engine before install for the pre-break in etc - but not 1000 miles...

I understand the "better to check anyway" philosophy - but why would this case be any different from a new car?

yeah, interesting question. I've often wondered myself, as I've done work on a vehicle that had a "no-retorque" head gasket, and I wondered what the difference was.

then there are some vehicles that recommend replacing the head bolts, and, in fact, they come as part of the head set. others don't. I don't know, maybe newer vehicles use a different head gasket design in combination with stretch bolts? pure speculation...

but yeah, I've also heard 500 mile retorque recommendation on this engine.

Me too...

FYI, I rebuilt mine about 20k ago. Never retorqued. No problems. And it has been a very hard last 10k.

Well, I would strongly encourage anyone to at least check the head bolts because I had mine back out (loosen way up) and blow the HG after only 5000 miles after having a freshly resurfaced head put on a very well cleaned (but not resurfaced) block. I also had reused the head bolts that time, so maybe that played into it somewhat.

Yea, you should never re-use TTY (torque to yield) head bolts.

It's my understanding that these bolts are not TTY.

>>>*Yes, a very good question. The easy answer is in the field we are not dealing with all new, we are dealing with partially new.

On new vehicles, typically machines set the bolts, the clamping force is then consistant. The block and head(s) are new, thus also the bolt holes, which are perfectly clean and free of debris.

*Well, that is what they hope, anyway. I have seen new engines fail gaskets, my Father's new 1961 Chevy 1/2 ton for example. He didn't make it the 13 miles home from the dealership. Rare though.

In the field the installer puts in one bolt at a time. Then they are tightened hopefully in three stages, in proper sequence.

Trust me when I say that varies from one set of hands to another. So in the field, the process is completely different than in the factory. If the installer takes great care, has very good hands and follows each step perfectly, there is probably no need to retorque.

On any engine I build myself, I double check after warmup, and find one or more move slightly around 75% of the time.

That with me tending to be a tad on the fussy side about an assembly.

In MHO, it is best to do a retorque and all engines that are NOT torque to yield.

TTY bolts are a different critter and designed to eliminate the need to recheck. But they also require all threads and bolts being very clean. On those designs I "work" the bolts, by taking them to the typical first torque stage 4-5 times to help bed the bolt. You will notice that even at 35 ft lbs, the bolt will go a tiny bit farther each time. It's when it does not go any farther that you are ready to continue..(I use that same procedure with ALL new fasteners, including conventional.)

*Sorry for being long winded, but fastener tech is complicated......*EB