Built an engine over the winter and have been dealing with issues this summer. In the process of trying to make it run better, I did a compression check.

Specs:
Brand New factory Toyota short block
Engnbldr RV head

I have about 1,500 miles on the engine now. Using nothing but Castrol GTX 10W-30.

Break in:

Right now it runs OK (two clicks on the AFM helped a lot). Cam looks good, nice clean wear on the lobes, good pools of oil on the top end. I get a little bit of a wonky idle, some of which I think is do to the 261C cam and some I think is do to the ECU (maybe a EFI temp sensor that is off). Mostly with the AFM and careful idle screw adjustment, it runs pretty decent now.

Cranking compression is around 135 psi on all 4 cylinders (it's even, just all low). Leak down shows about 30% leak, sound coming from dipstick tube. Squirted some oil into the cylinder, cranking compression goes way up to about 175 psi.

So the rings are the problem. Talking to Ted and some others, the thinking is my rings are not seated or I glazed the rings or hone. Anyone seen anything like this, maybe with a brand new Toyota engine or new factory short block? Trying to figure out if I need to be talking to Toyota about using that 12 month warranty or maybe if I need to do something in particular. Ted recommended some hard pulls or drag strip runs. I have not been particularly easy on the engine, but I'm sure it wasn't hard enough now.

Ideas, recommendations? I have this sinking feeling in my gut. I was so careful to follow a break-in, too.

 

Amazing that a factory block would be having ring seating problems UNLESS they put chrome faced rings in the engine. Chrome rings are pure hell to seat. They are fickel and only respond well to heat and loads to seat. I would dump this back on Toyota if you are nearing the warranty periond. I always use Hasting iron rings. They usually seat withing a day or two even on old engines that have been honed and simply re-ringed. You may want to literally go climb mountains for a day in hopes that the loads will seat the rings. YOur compression readings are too low and unless your cam is mistakenly out of time, the rings need more run time. Ted's advise is right on but I would not put a lot of hard RPM's on the new motor but I would load it down to force the rings to seat.

My $0.02

 

Warranty-wise, I still have a few months (about 7 more before the period is up). I'm planning on talking to my parts guy, at least get a question or complaint on file, although I'm not sure it's really bad yet. The cam timing thing is important, but two things I think indicate my timing is OK is that the leak down sounds like the loudest noise is coming from the dipstick and two a squirt of oil makes the compression jump to ~175, both indication rings. I've looked and looked at the cam timing and it sure seems right. I have not gone to the step of tearing the front of the engine part, but with the bottom at TDC, the cam dowel is where I would expect it. Also I think the #1 is pretty much at TDC because when I put pressure on with the leak down tester, the piston does not move. I don't know what the factory rings are, but my guess is that since 22R blocks last a really long time that they would be rugged and so maybe it's a matter of hard loads and time to get them to seat.

Thanks for the thoughts. Ted's recommendation is to not worry too much at this point, do some good loaded runs (he even mentioned taking it to the strip for a few runs) and see what happens. I'm not getting any significant signs of other problem, no oil or coolant loss, no blow-by, etc. So they are obviously not completely glazed or shot, so a couple months of harder driving might just be the ticket.

 

Holy crap, does Toyota still have a few brand new blocks lying around?

Back in the 80's, there were quite few cases where the cylinders weren't honed properly from the factory and the rings never set in properly. It was one of those silent recalls Toyota had.

On the box of my Hasting rings, it recommends setting the rings something like this:

Bring the engine up to operating temperature (VERY important). Drive up to 25 MPH, put the transmission in 4 th gear and stand on the accelerator unitl you reach 50 MPH. Do this several times.

I'll pull the box out tonight and give you the description word for word.

In the meantime, check out this website and gather your own opinion(s).

http://www.mototuneusa.com/break_in_secrets.htm

 

MotoMan is pretty much the initial break-in I followed, at least as best as I could in a pickup.

 

Dave,
I'm curious how this problem ever resolved? I think your in Rising Sun too..
I have 2300 miles on my rebuilt and started going through oil after 1700 miles. No visible leaks, no plumes of smoke coming from the tailpipe. I do notice the tailpipe is black.....Did you get your solved?