Rebuild engine or rebuild head? (1 Viewer)

[cybrstar]

Okay so what do you guys think I should do? I have a motor inside the rig right now 1fz in a 93. Seems like the head is no good and there is valve contact preventing the engine to rotate. The block is supposed to have only 130k miles. I purchased another engine for a pretty good deal. So at the moment I have 2. Should I just rebuild the head on the engine that’s inside the rig or just go full blow rebuild the one outside of the truck and install a fresh new motor? I’m leaning towards just installing a fresh new motor but do know guys who have just refreshed the head and 100k miles later still no issues either over 400k on the OEM block.

 

[richardlillard1]

I’m not seeing how the valves are stopping anything. After tearing apart a truck with a broken timing chain, it appears to be a non-interference motor. To my knowledge Toyota has never published documentation to confirm this, but others have reported timing chain failure with nothing other than the engine stopping.

 

[cme4lyt]

Valves do not collide on our engines. That being said, I’d work on the motor outside the truck, a full rebuild, and then simply swap motors in and out over a weekend.

Nothing easier and more relaxing than working on a motor on an engine stand. Of course, you might go down the ‘while I’m in here’ rabbit hole.....

 

[Malleus]

It really depends on how much you want to spend. The lower end of these engines rarely fails; however, as has been noted, your valves are not preventing the engine turning over.

Since your problem is most likely a broken chain you have a decision to make. You have to remove the front end to remove the engine or replace the timing chain, so that's not in the calculus, but removing the front end of the engine on a stand is waaaay easier than doing it in the engine bay. It's also easier to pull the head and fix all the intake problems age has created. You do not however have to suffer through removing the exhaust, which is no small effort, if you work on the engine in the truck.

Your choice.

 

[cybrstar]

So what do you guys think if it’s not the valves contacting the block? What else would stop the rotation? Timing chain/cams are moving in conjunction when turning the crank pulley with both directions. Do valves unseat on these 1fz’?