Hello everyone,

I'm getting ready to change the heads on a 1989 pickup 4x4 with the 3VZ in it. The reason I'm changing the heads is because of burnt exhaust valve and for $240 I can get re-manufactured heads, assembled and ready for installation. The head gaskets were fine on this truck but since I;m replacing the heads I thought about upgrading the studs to ARP head studs.

Is it worth it? Are the Head studs on it reusable or is at least recommended to buy new ones that aren't ARP?

Truck is going isn't going to be a daily driver, more used for weekend outdoors activities from trails to camping and some light light towing.

Would love everyone's thoughts.

Thanks in advance.

-Nate

 

Thoughts?

Here they are: Two hundred, forty bucks for one or the pair? What exactly is done to the cylinder head casting(s) and component parts to qualify it/them as "re-manufactured"? I'm not familiar with that engine, but are the OE fasteners "torque-to-yield"? Does Toyota use studs instead of screws OE? I understand that ARP company has good reputation for providing quality fasteners, but I seriously doubt that they are "better" than Toyota genuine. What benefit do you anticipate you theoretically could realize by buying premium or modified aftermarket fasteners?

If it wuz me, and the fasteners are not TTY, I'd just clean the originals up, inspect, replace as necessary with Toyota parts and button 'er up. If TTY...new Toyota.

 

If you are putting on a 240 USD head, skip the head bolts.You will have sunk valve seats waaaay before anything concerning a head gasket and studs becomes relevant.

 

Toyota uses head bolts, not studs. They are NOT "torque to yield." (This comes up every now and then because of how Toyota recommends they be tightened.) Toyota has a TSB saying that it is NOT necessary to replace the head bolts when changing the head gasket. The FSM was written long before the trucks reached 30 years, so if it makes you feel better, go ahead and replace the bolts.

 

I wouldn't spend the money on ARP head studs or MLS head gaskets, for that matter.

Just keep it OEM, put her back together and get another 100-200k out of it before the gasket blows again.

 

The effort for the needed surface finish (RA) for MLS .... there is no way I would do that for a stock or mild 22-RE. Useless.

 

$240 for the set. As far as what qualifies them as remanufactured is they’re suppose to be dipped, reassembled with new components(idk if genuine Toyota) and resurfaced. So I don’t know if that’s remanufactured but they’re in better condition then the ones on it.

As far as if they're TTY or not. I don’t know but looks like I have some additional research to do. I’m sure I can find the answer to that based on another thread in here, so I’ll jump on that before I take any more steps and same for whether or not they’re studs or bolts(I think they’re studs).

The benefit I’m inquiring about is if they can be torqued down tighter than genuine because this engine has never had a head gasket leak(since you’re not familiar with this engine, HG leaks are one of the more common issues with the 3vz) and since I’m taking the heads off for the first time, I would like to take every necessary precaution to prevent it from ever happening. Plus I hope to go to forces induction at some point.

I would like to save as much as possible in this process but also want to ensure I’m not cheating out on something vital.

Thanks for the feedback, It looks like I need to get some more information figured out.

 

Sweet! Well, that answers that! Skipping the head bolts! New head gaskets and heads going on!

Thanks!

 

Well in that case I don’t need to feel better, I’m happy sticking with the head bolts on it.

And if I run into any issues either during installation or after I’ll deal with it as it comes.

Thanks for the information. Much appreciated. 🙏🏽

 

Sweet man, that’s what I’m going to do. Appreciate the feedback. 🙏🏽

 

Studs are much more forgiving than the bolts. Too much or too little lube on a blind hole bolt.. Blah blah..

The factory tolerances are much more tightly controlled than your FSM specs. We're not often working in clean rooms for example.

You'll find lots of things along the lines of "check your head bolts after the first heat cycle". For various reasons this is important. Another thing of note is from.the factory assembly line no one touched that engine that didn't have to before it rolled off the lot.. (Factory vs aftermarket..)

 

Hello Co_94_PU,

Last summer I used MLS head gaskets with the ARP head studs through LC Engineering on my 3VZ-E as part of a rebuild kit they offer.

The failure on the composite head gasket is usually on cylinders 1 and/or 6 because they are sharing the same geometry and that geometry affords one of the shortest distances in the head to block were a blind water gallery is closest to the compression ring in the head gasket. There are a pair of coolant galleries on the outside area of the cylinder in the block that are not copied in the head and therefore the gasket is pushed down into the block when the preload is applied by the head bolts or head studs and nuts. This it seems invariably causes the gasket material to rupture given enough thermal cycles and finally the gasket material will erode away to the point were the compression ring ends up loosing the gasket material that is keeping it sealed up against the head and the block. Once that happens the coolant can migrate into the cylinder and into the EGR if it is #1 that failed and the steel ring has collapsed. Fel-Pro head gaskets came with my 91 4Runner and the odometer was at 235K when #1 let go. As it had Fel-Pro it is assumed the Toyota recall was applied at some time in the engines history.

When I completed the rebuilt and was assembling, I hand lapped the engine block and the heads after machining and decking had been done and replaced all of the engine internals and reground the crank. Prior to the rebuild but after the HG failed three wrist pins were seized and one big end rod bearing was going south. Seeing how the Fel-Pro HG had let go and how the block and head interact across the gasket, the MLS-HG seemed like a great way to solve the problem for a hopefully long term solution.

Good luck with your rebuild and be sure the wrist pins are OK because that can make an interesting noise when the piston skirts are pushed into the cylinder walls as the big end goes around with the piston more or less stuck at an angle that is with the con-rod when they are seizing up.. These are semi floating wrist pins in the 3VZ-E which means that the pin is pressed into the rod and floats inside the bore in the piston. Wrist pins and pistons are matched when you buy a set. There are no C-clips required to keep the wrist pin in the piston, the con-rod takes care of that as it is a snug fit on the crank shaft in as far keeping it in position in an axial direction.

 

Thank you. That makes a lot of sense and truth be told, this is going to be rebuilt in even a clean garage so that input definitely helps.