Gnarly4X's 22RE Rebuild

[EASYRYDERDANGER]

I don't have actual specs, but at idle you should see zero to a sliver of vacuum. Basically it's a quick check to see if you have engine vacuum or positive pressure.  You could take off the oil cap too and see if alot of vapor/smoke is coming out...  It's just hard to believe that an engine after 10k is worn out, I like to believe it's something else.

[Snowtoy]

Hi bd,

20/20 hindsight ... yes I should have spent more time preplanning and doing more research with the "experts",.......................

The last thing you needed to do was more research prior to the rebuild, I think he was referring to what is causing your oil loss now before you decide it is the rings.  As mentioned do a comp/leak down test, that should give you an idea of the conditions of the rings.

I have done several compression tests.

What do the numbers look like?

If you are burning a quart of oil in 600 miles, the exhaust tube should be sooty as well, didn't you run a new exhaust, might pull the cat and see what the leading tube looks like as well as the cat. My '86 beater that likely runs more hours than miles a year around my property doesn't loose that much oil, and it looks like every oil gasket on it has a leak.

...........  It's just hard to believe that an engine after 10k is worn out.............

Same here, even Chicom pop metal rings should last longer than that.

[Gnarly4X]

...  It's just hard to believe that an engine after 10k is worn out, I like to believe it's something else.

Hi E,

The oil consumption has been about the same since I rebuilt it.  I also am very curious to find out what is causing it.  I believe there are only 2 ways cranckcase oil can get into the combustion chambers.

Gnarls.

[Gnarly4X]

The last thing you needed to do was more research prior to the rebuild, I think he was referring to what is causing your oil loss now before you decide it is the rings.  As mentioned do a comp/leak down test, that should give you an idea of the conditions of the rings.

What do the numbers look like?

If you are burning a quart of oil in 600 miles, the exhaust tube should be sooty as well, didn't you run a new exhaust, might pull the cat and see what the leading tube looks like as well as the cat. My '86 beater that likely runs more hours than miles a year around my property doesn't loose that much oil, and it looks like every oil gasket on it has a leak.

Same here, even Chicom pop metal rings should last longer than that.

Hi S,

I just ordered a Leak Down Tester.  I will do a leak down test and another compression test and report the results.

I did not have the larger exhaust tubing installed.  The cat has been removed, so I'm running the stock exhaust tubing behind the DT header.  The exhaust pipe does look sooty.  The are zero oil leaks, so the oil is being burned.

The amount of oil that is being burned is most likely coming from the crankcase, not from the top end.  Since at least one Toyota engine builder has seen this kind of oil consumption on a fresh rebuild in Toyota engines caused from bad rings made in China.  I was told that rings simply do not have enough tension to adequately seal them against the cylinder walls.... and may not be a proper metallurgical composition. 

I have spoken to a reputable Toyota engine builder who said that excessive burning can be problem when CHROME rings are installed  (instead of MOLY rings) with the improper RA/hone being machined in the block cylinder walls.  But I don't know how much oil consumption there would be in that case?

If the valve guides/seals were leaking there should be some smoke at startup...  again, I don't see any smoke or blow-by???

If I ever rebuild another engine, I will be anal+ about measuring and mic'ing every piece before and after machine work, and measuring the cylinder bores and RA, before assembly!!  I will not 100% trust the machine shop.

Gnarls.

[gnob]

Just to add.  I built a motor about 15 y.a.  my first.  It burnt oil about like yours, if not worse.  I just ran castrol gtx.  Anyway, long story short, eventually had ringlands fail and completely destroyed the motor.  At the same time i got 100+k out of it.
I had used total seal rings. I did spec them when installed.  I believe they had a bit too much expansion which eventually caused the ring or ringlands to fail.

[EASYRYDERDANGER]

the 3 most common I know of are rings, valve seals, and too much positive crankcase pressure.  Mark your drain plug, maybe there is an oil thief!

[cbeers]

If I ever rebuild another engine, I will be anal+ about measuring and mic'ing every piece before and after machine work, and measuring the cylinder bores and RA, before assembly!!  I will not 100% trust the machine shop.

Gnarls.


You believe the rings are bad.....poor quality....how would measuring catch this?
Not being a jerk just trying to understand/learn   
CB

[300k]

Have you tried the compression test with ATF in the cylinders?

[emsvitil]

If it's the rings, you  might be able to rehone cylinders and just get good rings.

[:)bestgen4runner]

http://engineproblem.com.au/engine_problem/details/5.html
I would also bore scope the engine and look for ring wash. I suspect this will be very evident on one piston. My guess is cyl #3 or #4.
Also one good scratch in the bore can also lead to oil consumption. Did You experience any issues installing one piston?
Read the part about the hone marks gone. 

[EASYRYDERDANGER]

Or you lined up all the ring end gaps, lol.  Gnarly installing his pistons like- https://youtu.be/D0n8N98mpes

[Gnarly4X]

Or you lined up all the ring end gaps, lol.  Gnarly installing his pistons like- https://youtu.be/D0n8N98mpes

Yep... that's me!!.... BUT... I'm wack'n those ignorant Democratic Socialist millennials!!! 

Gnarls. 

[Gnarly4X]

http://engineproblem.com.au/engine_problem/details/5.html
I would also bore scope the engine and look for ring wash. I suspect this will be very evident on one piston. My guess is cyl #3 or #4.
Also one good scratch in the bore can also lead to oil consumption. Did You experience any issues installing one piston?
Read the part about the hone marks gone. 

Hey BG,


Yes, I want to that block and all parts inspected, diagnosed, analyzed, and  checked out by a pro, measured, recorded, and try to find out the truth and facts on this engine rebuild failure.  Whether it's my incompetence, machine shop's bad machining, defective parts, Chinese junk, or just plain bad luck.

No, I didn't have any issues with the assembly.

Gnarls.

[Gnarly4X]

If it's the rings, you  might be able to rehone cylinders and just get good rings.

Hi e,

Yep... I could get by with just a rehone, new rings or new rings and new pistons.  BUT... since that will require me pulling the engine and completely disassembling it, I might as well just rebuild it from scratch.  One "backyard mechanic" guy where I work suggested I "drop the pan, unbolt the rods, pull the pistons and re-ring them.  That would be huge risk.  What if that does NOT solve the problem? What if its a piston problem?  What if the cylinders were over-bored by a .001".  What if the RA was wrong?  What if the cylinders are glazed?...   I'm trying to mitigate any further waste of time and money!!

This engine is coming apart and then I'll decide if I will rebuild it, or just donate the block for a core charge.

Gnarls.

[Gnarly4X]

Just to add.  I built a motor about 15 y.a.  my first.  It burnt oil about like yours, if not worse.  I just ran castrol gtx.  Anyway, long story short, eventually had ringlands fail and completely destroyed the motor.  At the same time i got 100+k out of it.
I had used total seal rings. I did spec them when installed.  I believe they had a bit too much expansion which eventually caused the ring or ringlands to fail.

Hmmm... interesting.

Gnarls.

[Gnarly4X]

Or you lined up all the ring end gaps, lol.  Gnarly installing his pistons like- https://youtu.be/D0n8N98mpes

I was anal about the ring alignment.  BUT....I have a question???  Do the rings rotate or move at all around the piston or do they stay in the position that I put them in according to the piston manufacturer?

Gnarls.

[Gnarly4X]

Have you tried the compression test with ATF in the cylinders?

No, I have not pumped any ATF inside the cylinders before doing a compression test?

Getting the compression readings will only indicate a measurement, right?  Whatever that PSI is per cylinder, I will still need to pull the engine and find out what is causing the oil consumption.

Gnarls.

[Gnarly4X]

If I ever rebuild another engine, I will be anal+ about measuring and mic'ing every piece before and after machine work, and measuring the cylinder bores and RA, before assembly!!  I will not 100% trust the machine shop.

Gnarls.


You believe the rings are bad.....poor quality....how would measuring catch this?
Not being a jerk just trying to understand/learn   
CB

Hey cbeers, 

Good question.

Are you asking how would measuring the rings before the assembly to determine if they were bad prevent the oil burning?  I would not know that.  That would be something that a person who has lots of experience with piston rings, like Jim at 22RE, or Tod at engnbldr, or a ring manufacturer QA person.  There may be a "measurement" for ring tension or pressure, but I haven't seen a spec on that. 

If you are asking about how will it be determined if the rings are bad, I will have a very reputable mechanic who builds 22s as a business determine if the rings are bad, and hopefully WHY.

Gnarls.

[Gnarly4X]

Looking back, one of the big mistakes I made was NOT verifying with the machine shop EXACTLY what measurements for tolerances and specs were done.  I asked, and paid them to spec all tolerances.  I will check with them to see if I can get a report or record of what exactly they did during the machining and tolerance checks.

I suspect it's possible they may not have checked for specific measurements like ring gap.... but I don't know that for sure.  They had the block, crank, rods, new bearings, pistons & rings, head bolts, timing cover.

Again, my ignorance on what I should know before rebuilding an engine.  My long past few engine rebuilds, I simply relied on the reputable machine shop and my conversation with the machine shop owner/manager about what I wanted and what he recommended be done to the block and parts.

Gnarls.

[Gnarly4X]

...  At the same time i got 100+k out of it.

Holy capity!!  I cannot image driving my truck for 100,000 miles with it burning 1 quart of oil every 600 miles!!  It was all I could do to drive it 10,000 miles!!!

Gnarls.

[Snowtoy]

I have yet to pull apart an engine that I rebuilt, so I don't know if they move, but some I have torn down the ring gaps were close together, so they could move.  However if they do, even if they lined up, do to their movement, they shouldn't stay lined up long enough to burn oil at the rate you are seeing.

Has it been burning oil since day one, or did you notice it at "X" thousand miles?

[EASYRYDERDANGER]

The rings should basically stay where you set them, if they didn't there wouldnt be any point on staggering them from the git go, which is to slow the gasses ability to travel between rings...

[emsvitil]

Google

'do piston rings rotate'

[Snowtoy]

Damn internet, no more speculating.

[OOPS]

They will move around!!

[EASYRYDERDANGER]

Here's another thought, maybe u installed one or more of the rings upside down..  typically the rings will have a marking that typically indicates it's to face up.  Also pretty confident rings don't move around once worn in. And u check rings by measuring ring end gaps with just the ring installed in the cylinder. All this is in fsm

[Gnarly4X]

Here's another thought, maybe u installed one or more of the rings upside down..  typically the rings will have a marking that typically indicates it's to face up.  Also pretty confident rings don't move around once worn in. And u check rings by measuring ring end gaps with just the ring installed in the cylinder. All this is in fsm

Hey E,

Good thought.  Right now I'm giving everything a thought.  I am sure I was extremely careful with locating the rings on each piston... but that doesn't mean I could not have made a mistake.  The rings did have a dot for indicating face-up to top of piston, and I located the each ring gap according the instructions/diagram in the box.

What is the likelihood that 1 or more pistons would rotate the rings to move gaps to be all aligned that allowed enough oil to be burned that I'd see 1 quart in 600 miles? 

I did check several compression rings for gap, but I don't remember if I check all of them.  I should have checked all of them for each cylinder that the pistons was going to be installed.

Although the ring gap spec in the FSM for a 22 is spec'd in 10 thousandths of an inch, the allowable tolerances between Standard and Maximum is a large gap!  So from that, I assume ring gap is critical but does not have to be precise.  The gap difference tolerance between maximum Standard and Maximum is about 0.0237", or about the thickness of 6 sheets of 20# printer paper.  In other words, the spec says this is the range:  .0098" to .0185" for the number 2 compression ring, which has the tightest tolerance.  But the FSM specs the "Maximum" ring gap for that ring at .0421".  So the difference in that range is .0236"!!

I got my leak down tester yesterday, so I'll do a leak down test and a compression test in the next two days and post the results.

My limited experience gut says the ring gaps is not the cause of the oil consumption.

Gnarls.

[Gnarly4X]

They will move around!!

I've read conflicting information on this. But I do know that in 2 cycle engines, the piston have a locating pin so the ring(s) cannot rotate, and avoid getting a gap edge hung up on the port inside the bore.  I raced go-karts for about 5 years, and went through about 4 engines - all 2 cycle.

I don't know if 4 cylinder pistons have locating pins for rings as standard design or they are in specific applications.  Or if they don't have them and it does not matter that the rings rotate... or NOT.

Gnarls.

[Gnarly4X]

Has it been burning oil since day one, or did you notice it at "X" thousand miles?

It has been burning about 1 quart in 500 to 600 miles from the day I fired it - day one.

Gnarls.

[blackdiamond]

Hi e,

Yep... I could get by with just a rehone, new rings or new rings and new pistons.  BUT... since that will require me pulling the engine and completely disassembling it, I might as well just rebuild it from scratch.  One "backyard mechanic" guy where I work suggested I "drop the pan, unbolt the rods, pull the pistons and re-ring them.  That would be huge risk.  What if that does NOT solve the problem? What if its a piston problem?  What if the cylinders were over-bored by a .001".  What if the RA was wrong?  What if the cylinders are glazed?...   I'm trying to mitigate any further waste of time and money!!

This engine is coming apart and then I'll decide if I will rebuild it, or just donate the block for a core charge.

Gnarls.

Rebuilding from scratch makes no sense if you find a cause of the problem and the primary goal is a running engine. You could get a professional rebuild and have a random failure even then.