Burning oil and smoking after fresh rebuild!

[thinhman]

Okay so I just got finished rebuilding my 7m-ge. I am still in the process of breaking it in (250 miles ATM, but this is my daily) and I am smoking lots of blue smoke. Usually I know that it's whatever oil deposits that are in the exhaust, cat, or whatever that is burning so I didn't mind it much.

After a while I started to notice my oil level going low on my dipstick. I fill it with 6 qts of Valvoline straight 30 w/ detergent and I had to fill a quart up yesterday and today because the dipstick reading was low. I am not visually leaking any oil...anyone have any suggestions?!?! I've done my searches already for a few days now and nothing that really points to my answer.

I have new pistons + rings and new valve seals and also am not leaking coolant. I broke it in my the "hard" method but I might have accidently drove it at WOT from not being accustomed to the throttle sensitivity (Drove a van during the rebuild; those throttles are heavy).

Any response would be greatly appreciated.

 

[benchwarmer]

Did it start smoking as soon as you started driving it or did it start smoking as you put miles on it? If it has always done it I would suspect an incorrectly installed valve stem seal. If it built up over time then maybe poorly seated rings. A compression test should tell you if your rings are bad.

 

[CyFi6]

What kind of rings did you use? Did you have the cylinders all honed to specs? Were the rings gapped and positioned properly? Also, what kind of valve stem seals were used/were they replaced with the rebuild?

 

[thinhman]

benchwarmer: I'm not 100% sure but I believe it started smoking after I put some miles on it. The valve stem seals were installed by a reputable head mechanic so I trust he installed them correctly. Even if he didn't install them correctly, would that be my cause of an oil loss? Would poorly seated rings really cause that much of an oil loss as well? Would that WOT run mess it up? :cry:

cyfi6: I used NPR rings as I stated in the first post. Yes I've had my cylinders honed along with the block being decked and such. I followed the procedure in the TSRM for gapping/positioning and installed the rings correctly. The valve stem seals were replaced with new ones but I do not know which kind he used. I can ask if it can determine something.


EDIT: I believe I've been smoking SINCE I rebuilt the engine. I remember one of my buddies said I was smoking a lot. I don't know if I was losing oil at the time but I know I puffed lots of smoke since the engine started up. I just thought it was normal due to the oil settling in the exhaust and what not.

 

[AJ'S 88NA]

First start up smoke is normal due to using oil to install the rings, if you used oil to install the rings. That's what it sounds like to me is the rings haven't sealed. If you went by the TSRM and gapped them right, staggered the gaps right, bore was even all the way, then it could be the stem seals. A leak down test might point a finger as to were the problem is.

 

[thinhman]

Alright I'll run a compression test and a leakdown test when I can. I'll post back results when I get them. I didn't know rings would eat up that much oil...
It sure seems like a lot. Plus I did fill it a quart over.

Any other suggestions in the meantime?

 

[supraduper]

whats your experience building engines? is this your first one?

more information on your abilities will help us all ask the right/important questions...

if this is your first build, i would ask different questions than if you have built 10 engines...



also isnt 6 quarts a bit much? i ran 6 quarts by mistake(wrong dipstick) and the oil was sloshing against the crank and rods....


did you measure the engine yourself? bore taper?
or did you just give the engine to a shop and say hone and deck this.... in my experience if thats what you said, thats what they do...

also did you supply the specs for honing the cyls to the shop? as they may have just "winged" it

 

[thinhman]

Yeah its my first engine rebuilding but I two friends over. One friend who had rebuilt a few 7m's already, and another friend who is a complete mechanic who has been building engines since he was 15 (22 now).

My head/block were done by a reputable machinist and no I did not give him the specs for the hone but they've dealt with 7m more than they can remember. If anything they're both toyota specialists; one of them especially supras. So highly doubt they "winged" it.

Well wasn't standard oil capacity 5 quarts? I always read add one more quart extra for safety measure.

 

[supraduper]

that sucks man... i feel your pain as far as, thinking everything was done right. and thinking your gonna have a great running engine... to find out maybe not...

i did a fresh rebuild on my engine... but inadvertantly left a rag in the hole where the mechanical fuel pump used to go when i was painting the block... 3 days later no oil pressure.... kinda like wtf!!!! so stupid i felt... however i am sure someone was trying to sabotage me... at least it helps me sleep at night...

honestly... at this point.. your pretty sure everything was done correctly... so you need to do a compression test as stated above and go from there....

also just a thought... you're positive you installed the rings right.... the 2 compression rings look similar... and there is an up and down, regarding which way to install

i ask, b/c u could have excessive blow-by if the rings are upside down

i know you said you read it... but just peace of mind on my end

*edit* you will have excessive blow-by... not could lol

 

[AJ'S 88NA]

6 quarts is fine, no way it would slosh with the crank.

 

[supraduper]

i agree... i think i had like 7 qts...

i didnt realize that my new engine i rebuilt was a cressy engine... so the dip tube is in the front of the engine... where as the dip tube on the supra is in the middle... and since the engine doesnt sit level...(higher in the front) i couldnt get a reading on the dip...

so after a while i knew it didnt feel right... huge loss in high RPM power.

finally got a cressy dip stick and tube.. ahh.. peace of mind

 

[thinhman]

i agree... i think i had like 7 qts...

i didnt realize that my new engine i rebuilt was a cressy engine... so the dip tube is in the front of the engine... where as the dip tube on the supra is in the middle... and since the engine doesnt sit level...(higher in the front) i couldnt get a reading on the dip...

so after a while i knew it didnt feel right... huge loss in high RPM power.

finally got a cressy dip stick and tube.. ahh.. peace of mind

WAIT WHAT??!?!?!

Dude I think you just solved my oil issue?! Maybe I'm not leaking oil after all?!?! The block I am using was originally from a cressida...but I removed the dipstick and tube from my supra block....I don't know about front and middle placement? But I did change the oil pump and oil pan to the supra for the mid-sump instead of front. But I do get an oil reading on my dipstick....so nevermind disregard that lol.............

Unless the cressy dipstick is longer or something like that than the supra? And I could be getting inaccurate readings?

 

[thinhman]

Okay so the dipstick thing is making me very curious. My dipstick tube does not sit in snug. I can pull it out along with the stick and the one I am using now is from my supra, but the block is from a cressida. But the placement is the same/similar as the supra's. It reads oil level from high to low, and when its low I still have ~30 psi at idle.

I also have vacuum coming from my dipstick....if I pull out the dipstick while the car running my rpm drops as it would from a vacuum leak. If I put the stick back in rpm raises back to standard idle. What's up with that?!?! Could that be blow-by?!??!?!?!

Any help is GREATLY appreciated. I don't want to start over on a rebuild

 

[supraduper]

check your vacuum diagrams.. and make sure everything is perfect... then get back to us

its easy to mix up the vacuum routing.... i drove for 2 months without my acis working...

i bet you have manifold vacuum where it doesnt belong.. hence the oil consumption

 

[CyFi6]

You are supposed to have a slight vacuum on the crankcase to pull out any gasoline vapors, but it shouldn't be excessive. Your idle should change slightly when you pull the dipstick out or remove the oil cap. Check to make sure your pcv routing is proper, but what you are describing is normal

 

[supraduper]

i also just did a fresh rebuild.. i havent noticed any change in idle when the dip stick is pulled... there should be vacuum... but i dont think it should be obvious...

also how could anyone mess up the pcv system? lol the two outlets on the valve covers connect to the big port on the TB..

 

[thinhman]

All my routing is correct; like I said I had a few buddies check it out. None of the hoses are misplaced. What I do think though that I might have one of them clogged. I didn't clean the throttle body too well.

Would oil filling spark plug galley 5 + 6 have anything to do with me burning oil? The plugs aren't loose so there would be no way it could drip to the pistons.....just a thought?

I am going to head to the junkyard too and see if I can pull a cressida dipstick. I also plan to flush the system and see if I get more than 3 quarts left in the system when my dipstick is reading low; that way I'll see if it is strictly a dipstick issues.

 

[supraduper]

get a vacuum gauge and check what you have at idle... maybe you have too much... and its sucking all the oil in through the pcv inlet...

maybe you could plug that port see if that helps

 

[AJ'S 88NA]

get a vacuum gauge and check what you have at idle... maybe you have too much... and its sucking all the oil in through the pcv inlet...

maybe you could plug that port see if that helps

Do not plug the pvc port, you'll have oil leaking somewere else like the crank seal,cam seals, oil pump drive shaft.

 

[thinhman]

That's what I thought....I was so confused from that post.