I was helping a friend tune up his 22R, with a weber.
While setting the timing and adjusting the carb I gave the throttle a couple quick snaps, next thing I know...the bottom end is knocking, bad.
He said they simply don't rev to anything higher than 3000 rpm. I may have exceeded 3k, but not by much.
He also said these bottom ends are super weak and top speed driving up I70 out of Denver (pretty steep pull) is 20 MPH.
I call BS, unless corrected? I've been tuning cars and trucks for 25+ years and have free reved these engines repeatedly and never blew a bottom end. I've heard chain slap, but never a rod/main knock from a simple rev.
He said he replaced rod and main bearings 200-300 miles prior. Did he install them wrong?
If you don't true the crank will this happen?
My experience with 20r engines is you can't hardly hurt them and will take running 5k rpm all day.
True false?
SD

If what I did blows up engines, I should have destroyed a 1000 or more by now. (this is the first)

I pull hills @4500 rpm in my 4Runner routinely.
No issues except the gas gauge goes down a bit faster than normal.
He must not have installed the bearings correctly for this to happen. maybe he slapped a new set on the crank without any work on it?

I took I70 thru Eisenhower Tunnel in my carb'd 86 a few years back goin' highway speed, so I don't know what he's talking about. I might've dropped down to 45 mph, but not no 20mph. I've tached the crap out of my 22R's too; top end is actually around 5200 rpm, IIRC. People bang 4K a lot if they're hot on the pedal.

You'll suck a valve before you whack a bottom end on these in my own experience.

My bet is on the assembly/lack of machining phase of reassembly.

My plugged nickels.

He has no idea what he's talking about. rev limit is 5750 on 22re's. You get valve float over 6000rpm on stock valvetrain..

>>>*I have an opinion, since I have had a few thousand parts and pieces in my hands over the years.

The factory steel crankshaft is extremely strong, forged steel, and held in place by five main caps with very large fasteners. Five main caps that STRESS to round under full torque load? Even the high horsepower V-8's aren't made that way. It creates amazing rigidity.

This creates a block foundation that is extremely strong, far stronger than 90% of the four cylinder engines ever produced. Stronger than most much higher power output V-8's!

Most four bangers have just four main caps. V-8's have five also, but normally much lighter duty.

Then we get to the connecting rods, they test at 400% stronger than they need to be to handle the factory less than 120 H/P.

I know. I have tested them.

The pistons? Well, I have seen stock ones with 300K on them that I could put right back in without a second thought. We supply aftermarket pieces using factory specs that will easily handle in the mid 130 to 140 horsepower to guys that run around with their foot to the floor all day every day and expect to see another couple of hundred thousand miles use out of the rig they rebuilt....at a couple hundred thousand miles.

*Many with far more miles than that!

The valve train? Guides failures are almost unheard of, and the only time we do see problems are traced to the result of tuning errors.

The only time we see early failures after a rebuild are in "NO-Fit" situations, tuning mistakes, or lack of lube conditions that will fail ANYTHING ever built on this planet!

The weak link? That silly hydraulic timing chain tensioner, it must be clean or it will stick. The OTHER weak link? Yes, a bit short on ponies with a big job to do, but even with your foot on the floor, if all is up to snuff they just keep going and going and going.

Get her way too hot and she will pop a head gasket, so will anything else. Miss on the timing or get an air leak and the result is the same. Don't wash your hands and everything else when bolting her together and you will get to replace the timing setup.

Stuff a too long bolt into the oil pump and jam the tensioner? Yep, it becomes defective real quick!

Rather than being "weak", it is one TOUGH little thing!

Now we build smallblock Chevies that make 80 plus horsepower per cylinder, the 22R/RE bottom end tests stronger, and not by a small amount.

The 22R can be made to make 300 H/P of course, it's just tough to drive it to the grocery store like that, so streetable is pretty much 140 or so.

Bigger and stronger crankpins, bigger and stronger connecting rods, better and slower bearing surface speed, stronger pistons, tough valve train!

If it had a cast iron head nobody would ever be able to sell an engine part for one of them. Aluminum does get very unhappy when overheated, but it is nice and light.

This is part of why so many folks will part with their Dog or maybe even the wife and kids before they will let the "Yota" go.

Add in that if you have a Crescent wrench, a screwdriver and some basic hands tools and you can fix nearly anything that does mess up out in the woods?....

This old man disagrees with your friend, but then I am prejudiced...*LOL**...You may tell the gentleman I said so...*EB

Thanks, fellows! It was one 3k free rev that did the damage.
I wish they would put a good used engine in it instead of trying to fix this one.
They are are mad at me for blowing up their engine.

I told them that these engines are one of the most reliabe engines ever and it should not be blowing up with a little rev.

Oh well.

SD

Hah, if they still are haters, just print out the thread for 'em. We stand by our faithful little steeds. <img src="/forums/images/graemlins/cheers.gif" alt="" /> <img src="/forums/images/graemlins/cheers.gif" alt="" />

I think you need to ask them to explain how they KNOW it was your revving that did it, and not just coincidence.

Hell, if you use the ECT on the auto transmission it dosn't even shift until after 3k RPM. Ask them how Toyota managed to design a transmission which shifts above the alleged "breaking point".

Nah, i can get my dads tranny to shift at 2000rpm with the ECT on if i baby it, (it just like a tow/haul mode on a chevy).

But yeah, 3000rpm the motor is just purring along... now if it was a valve-floation 6000 rpm rev.... then i'd blame you....

HAAAAHAHAHAHAAAA!!!

AHHHHHH-HAHAHAHAAAAAAAAAAAAAAA!!!

stop, stop, you're killing me! <img src="/forums/images/graemlins/smile.gif" alt="" />