Thoughts on this compression test.

[landcruisertx]

Background on the patient, this is my 1996 80 series who was a one owner rig before I bought it. I acquired it with 245k on the dash and have driven it to 300k since in 3 years. Fun fact, a family friends son who was an NFL player back in 95 bought it off of his NFL bonus check. This is my daily and the reason I decided to do a compression test is she is eating oil by the quart, about every 600-800 miles. I have quite a bit of detonation at just about all speeds at light throttle. (beans in a can sound) Below are my compression results. I daily this rig and am seeing how serious of a rebuild I need to do. Head refresh or bottom end as well. I have everything I need to do a leak down test focusing on cylinder 3. Not sure how I two interpret 1-3 then 3-6 having such a large difference. Not meeting the all above 171 and no more than 14 psi between each. She drives pretty well other than sometimes being bogged down by the A/C being on and the the pinging.

Done on a warm engine, T1 is the first test, T1 Wet is a teaspoon of oil and T2 wet was the second. Thank you, all!

 

[RevISK]

Other than 3 climbing, which is strange, those don’t seem like terrible numbers.

 

[baldilocks]

It doesn’t appear you have a piston ring issue. I’d agree with the above post. Can you post pics of the plugs? Have you determined at what times that blue oil smoke emits from the tail pipe. Perhaps you need valve guide seals only.

 

[landcruisertx]

It doesn’t appear you have a piston ring issue. I’d agree with the above post. Can you post pics of the plugs? Have you determined at what times that blue oil smoke emits from the tail pipe. Perhaps you need valve guide seals only.

Sometimes upon start up, when idling for a bit then pressing the gas. When getting into motion there’s a some smoke at times at the very start. Top to bottom is 1-6. Also I believe the burning oil has killed my cat I replaced a few years back. Code P0420 is on the dash. 1 year old 02 sensors.

With how bad the pinging has gotten I’m thinking at this point I have to at least pull the head. When I bought the car I fully redid the cooling system and I only run mid grade gas. Spark plug replaced about a year ago..

 

[MissahPapaJ]

How new is your PCV? and is it a OEM? I’ve seen aftermarket PCV’s do all kinds of weird things. Especially oil consumption. Also how’s your MAF readings I’d possibly look into that for the pinging.

 

[manofthewoods]

Sometimes upon start up, when idling for a bit then pressing the gas. When getting into motion there’s a some smoke at times at the very start. Top to bottom is 1-6. Also I believe the burning oil has killed my cat I replaced a few years back. Code P0420 is on the dash. 1 year old 02 sensors.

With how bad the pinging has gotten I’m thinking at this point I have to at least pull the head. When I bought the car I fully redid the cooling system and I only run mid grade gas. Spark plug replaced about a year ago..

View attachment 4197520

Given what I see in the photo, the plugs appear good

 

[landcruisertx]

How new is your PCV? and is it a OEM? I’ve seen aftermarket PCV’s do all kinds of weird things. Especially oil consumption. Also how’s your MAF readings I’d possibly look into that for the pinging.

I replaced with OEM when I redid valve covers seals

 

[RevISK]

Hard to tell from the photo but are the plugs covered in ashy deposits or just discolored?

 

[landcruisertx]

Hard to tell from the photo but are the plugs covered in ashy deposits or just discolored?

White-ish deposits, I’m thinking it’s running hot/burning a lot of oil (which it is) or it’s too rich. Looks like pretty good carbon build up too.. What’s your read?

 

[RevISK]

White-ish deposits, I’m thinking it’s running hot/burning a lot of oil (which it is) or it’s too rich. Looks like pretty good carbon build up too.. What’s your read?

View attachment 4197568

That one doesn’t look terrible.

Lots of ashy deposits usually mean misfire and/or burning oil. You know you’re burning oil so…

 

[TheBussman]

compression test looks fine but that does not mean that the rings arnt letting alot of oil past. completely possible that a engine runs great, passes leakdown and compression and still has a ring issue making it burn oil. very lkley that the valve steam steals are leaking if its blue on startup. valve seals alone may or may not take the oil consumption down to an acceptable level if your 100% on the PCV. What's your timing set at?

 

[landcruisertx]

compression test looks fine but that does not mean that the rings arnt letting alot of oil past. completely possible that a engine runs great, passes leakdown and compression and still has a ring issue making it burn oil. very lkley that the valve steam steals are leaking if its blue on startup. valve seals alone may or may not take the oil consumption down to an acceptable level if your 100% on the PCV. What's your timing set at?

3 degrees using a computerized timing light to check. Here are some pics of my exhaust side valves when I did exhaust gaskets a few weeks back.

 

[baldilocks]

Based on the photos of the valve stems and when you are seeing smoke, the valve stem seals are definitely leaking.

Have you verified oil pressure with a test gauge? If that and a leak down test don’t point to rings I’d be confident your problem is stem seals. At 300k it’s probably ready for a new head gasket and full on head refurbishment.

How much oil leaks onto the ground???

 

[RevISK]

3 degrees??

 

[landcruisertx]

Based on the photos of the valve stems and when you are seeing smoke, the valve stem seals are definitely leaking.

Have you verified oil pressure with a test gauge? If that and a leak down test don’t point to rings I’d be confident your problem is stem seals. At 300k it’s probably ready for a new head gasket and full on head refurbishment.

How much oil leaks onto the ground???

Rarely does any leaking ever make it to the garage floor. Maybe a drop once in a while. Have not tested oil pressure. Hopefully I will have leak down results tonight.

 

[landcruisertx]

3 degrees??

Yes, 3* BTDC, I believe this is standard spec. I’ve not tried advancing to 5ish. I believe the issue isn’t in the timing though. Unless you have a differing opinion.

 

[RevISK]

Yes, 3* BTDC, I believe this is standard spec. I’ve not tried advancing to 5ish. I believe the issue isn’t in the timing though. Unless you have a differing opinion.

I am coming from 2f and 3f land where we start out at 7* and advance up to 10-15 as needed. Is it that different with a 1FZ-FE?

 

[landcruisertx]

I am coming from 2f and 3f land where we start out at 7* and advance up to 10-15 as needed. Is it that different with a 1FZ-FE?

Yessir, Just confirmed in FSM picture as well as watched OTRAMM video.

 

[baldilocks]

The pinging you here from the engine could actually be due to a lean condition caused by poorly functioning O2 sensors.

 

[landcruisertx]

The pinging you here from the engine could actually be due to a lean condition caused by poorly functioning O2 sensors.

Good thought- I’ve replaced both in the last year. They could be gunked up again however I had some pinging before I replaced them as well.