Rebuilt my 3rz!!! SHES A RUNNER

If I were building the engine it being a cast iron block I would have it hot tanked and magna fluxed. If the cylinders didn’t meet spec I would have it bored. If the crank checks out to spec I would put it back with std. bearings. I always replace the cam shaft with almost any build. The head or heads depending on engine type always get rebuilt/remanufactured. As far as the rest of the components they get replaced.

This is just a general idea IMHO. Sure you can pick it to pieces but it’s a general idea as said.

 

The cam shaft is a critical part and with just the smallest amount of wear on the lobes you will not achieve maximum performance. Again this is JMHO will it run with the old cam? Yes, but since the OP has now disclosed his engine has 285k miles it would get replaced.

 

I got a new head with cams and valves installed already so that’s all good there.

 

I knew you were all set from the get go. I just put all these post up for the critics lol.

 

What is the crankshaft spec where the rod bearing goes onto the crankshaft?

 

Like right here. So I can measure for tolerances when I get the new bearings.

 

I don’t have a repair manual on this particular engine but I did find this.


1998 Toyota 3RZ engine, the rod journal specifications are typically around 53.01mm (2.087 inches) in diameter, with a standard bearing thickness ranging from 0.0015" to 0.0025" depending on the brand and application.

 

awesome. Thank you.

 

Three decimal places on the inch measurement isn't enough precision when you have to measure down to tenths (ten-thousanths).

Standard crank pin per the manual is 52.987 – 53.000mm (2.0861 – 2.0866").

 

awesome thank you! I’ll measure that tomorrow and make sure it’s within spec.

 

I'm all for doing things right the first time. I just got done rebuilding a stroker engine for my VW last winter. I maybe rebuild an engine once every ten years and I have to research and ask lots of stupid questions every time. Just beware of the advice you get on forums. Some people have no problem insisting you need to replace everything when it's not their money that's getting spent or they don't know how to find out if it needs replacing. If your not replacing other parts of a valve train and there was nothing wrong with it in the first place, then more than likely it's fine to reuse. Measurements can be taken, but a close look at the cam lobes and bearing surfaces should be enough to give you a hint that maybe it needs replacement. Sorry TOP DOG, not trying to pick a fight, but I had to speak up before you convinced him to waste his money on something he didn't need. If the cam isn't worn out the only other time I know that you would need to replace it is if you have lifters and the lifters are getting replaced. The new lifters often need to 'break-in' with a new cam and that can ruin an old cam that has already been broke in. If someone who knows better wants to correct me please do. As I said I'm no professional, but I've been around the block a few times.

 

You are entitled to your opinions right or wrong no fight here. I do feel that an engine that has as many miles as the OP has stated to be properly rebuilt would warrant new cams. But we are debating something that the OP has already settled in post #103 so what’s the point?

 

That's mostly applicable only to the flat tappet pushrod cams found in old V8s, I6s, and some OHC follower designs. The advent of roller followers made it unnecessary. Shim-over-bucket like Toyota uses pretty much requires that the shims can be replaced without affecting the cam or it would mean replacing one or both cams and the 8 shims under each one every time the valves needed adjustment. I don't think that even supercars have that kind of burdensom maintenance requirement.

I have wondered many times why Toyota took so long to use hydraulic valvetrain in truck engines (the 2TR does) other than perhaps it gets them some money at the service department down the line. I mean a least they're not shim-under-bucket where the cams have to come out for a valve adjustment, but still. And why is it even DOHC? But I digress...

 

Hydraulic lifters with needle bearings in it is one of the stupidest ideals they ever came up with

especially in an interference engine......just plain stupid

without bushings.....its a bad design

 

can I run full synthetic in my 3rz after I break it in or should I run blend? Also 5-30 or 10-30. I’m in northern Nevada where it gets really cold and really hot.

 

I ran that purple breakin oil for 1st 500mi

then I switched to Valvoline Vr1 racing......nascar uses a convent sae30 break-in until about 5k

both these are high in zinc for flat tappet break-in


Then just ran synthetic blend valvoline / napa until 25K...what ever was cheapest, on sale

Now switching to pensoil platinum ultra......or just as good valvoline extended protection synthetics
these are currently the top dogs.......at least for anti wear additives


these engines where designed back in the conventual days.......I wanted to breakin the same way
But yeah.... everyone should eventually switch to synthetic....it offers much more protection especially in extreme hot/cold

we are so lucky to have those stainless shims.......they beat the shit out of everything else

those needles in lifters were not a good ideal....impact radius is way too small

Ive seen those shims with well over 300K and no measurable wear
if they took care of it

Toyota makes(used to) engines as good as honda motorcycle engines....
you know, the kings of the world in small engine world

 

All my old japanese sport bikes had shim under bucket design. I've got a big organizer full of shims for 80s and 90s suzukis. Perhaps it is just what the japanese felt comfortable with. Most all these cars companies started their lives with making scooters and motorcycles.

 

Probably every 50K I'll run that Valvoline restore for 1K.......

because I have 4qt 2.4....I change oil every 2K
but only change the filter every 3 or 4th time...

makes for a 5min oil change

 

Why?

 

they should of used a bushing instead of bearings
its simple physics.....it increases the distribution of the impact area immensely


a diesel with half million miles......these are the weakest point....single most likely to fail internally


I'm not sure.....its like with the turbos.....its like they want it to fail....