Cylinder head bolt questions (1 Viewer)

[sggoat]

Low compression numbers on #3 and #2 prompted the head removal on my 79 2F.. # 3 had a beach sand coloured exh valve-#2 is slightly light coloured as well--. The machine shop should be able to correct(if the seats are ok). Have all new exh vlvs/guides/seals/keepers.
When the head hopefully gets rebuilt--what is the best process for re-install of head bolts? The originals have been reused twice before--they look to be in good shape. I understand these orig Toy head bolts are not "stretchable" and can be used over again-Toyota still has head bolts available for this year--
Are these bolts still the non-stretchable type?
Can one use Nikall anti sieze for the threads(and is this even advisable)?--
Thanks for any help from the forum----
Gary

 

[brian]

nothing more than a little bit of lite oil on the threads....anything else will/could give a false torque reading(too much).
yes these head bolts can be re-re-re-reused, as they are not the torque to yield type(single use).
chase the threads in the block before reinstalling.

 

[Skreddy]

nothing more than a little bit of lite oil on the threads....anything else will/could give a false torque reading(too much).
yes these head bolts can be re-re-re-reused, as they are not the torque to yield type(single use).
chase the threads in the block before reinstalling.

I agree. In addition, I put a drop of oil under the bolt head/washer to also help with torque readings.

 

[DougAustinTx]

Don't use a tap to chase the threads in the block. It will inevitably create slop in the threads. If you want to clean the block threads, use a spare head bolt and cut 3 evenly spaced vertical grooves in the threads with a zip/zit wheel. That will clean the threads without enlarging them.
Doug

 

[65swb45]

/this\

 

[sggoat]

Got it all. Thanks to everyone for the help! I really like the idea of using the spare bolt to clean the threads---just that I don't have one-- Toyota still has these available)--they are like $9 each, so buy a new one and use one of the old ones as a "tool"

 

[65swb45]

Got it all. Thanks to everyone for the help! I really like the idea of using the spare bolt to clean the threads---just that I don't have one-- Toyota still has these available)--they are like $9 each, so buy a new one and use one of the old ones as a "tool"

It’s all about the timing Gary. I could have easily dropped a used one in the box with your wiper linkage last week. Oh well.

 

[Blastservices]

Head bolts with corrosion signs and pitting will for sure have more elasticity than a clean brand new bolt. Corroded bolts will allow stretch and a head gasket to leak. I know this and even went against this knowledge because of the re re re use theory older engines have and it bit me. I just had to re do all the gaskets and all the work over again on a F155.
Just buy new bolts it’s cheaper and less hassle.

 

[sggoat]

Well, I did get a bolt ordered from Toyota--{-Mark--my bad-I wasn't thinking!}
Out of the 15 original bolts there was only one that showed any hint of 'orange' (zero pits)-it was surface rust, cleaned right up with a scotch brite pad-but it will be the "tool' candidate--can cut the treads and then run them hard through the wire wheel to get rid of the little blue wafer wheel nibs.

The head came back from the machine shop--three exhaust valves bad-all new now, and intakes were all ok. Only 5 of the springs were still in spec(height and vertical square). Fortunately, the spare set I had was all ok, so the shop used them.
The shop inadvertently popped out the rear freeze plug 'cause they thought it was corroded(it was brass). They couldn't find another brass 50 mm plug so now I'm searching for that(anyone have a source for these?)

Try to post some pics of the exh vlvs and the block clean-up tomorrow--

 

[65swb45]

Well, I did get a bolt ordered from Toyota--{-Mark--my bad-I wasn't thinking!}
Out of the 15 original bolts there was only one that showed any hint of 'orange' (zero pits)-it was surface rust, cleaned right up with a scotch brite pad-but it will be the "tool' candidate--can cut the treads and then run them hard through the wire wheel to get rid of the little blue wafer wheel nibs.

The head came back from the machine shop--three exhaust valves bad-all new now, and intakes were all ok. Only 5 of the springs were still in spec(height and vertical square). Fortunately, the spare set I had was all ok, so the shop used them.
The shop inadvertently popped out the rear freeze plug 'cause they thought it was corroded(it was brass). They couldn't find another brass 50 mm plug so now I'm searching for that(anyone have a source for these?)

Try to post some pics of the exh vlvs and the block clean-up tomorrow--

I think the freeze plug is still available from the dealer. And I definitely prefer the genuine part on this over ANY aftermarket. I have WAY too many stories under my belt about fighting with machine shops over aftermarket plugs that failed.

 

[Blastservices]

They are. There is two different part numbers. Look up F155 and 2F and give them both part numbers and see which they can get.

 

[sggoat]

pics of the bad exh valves