Rebuilt engine: blue clouds / oil burn--AFTER warm up

docLocke · Post by **docLocke** » 07 Mar 2016, 18:51

Working two+ years on a father-son 98 850 V70 rebuild. Parts from everywhere, pipeline to the junkya..(sorry) recycler. Interior black on black, exterior ready for paint, almost ready for the road, but..
Engine/transmission a swap and mate to get turbo manual from turbo auto/manual NA. New gaskets everywhere. New rings; bearings checked out. Head: valves cleaned, new seals.
Compression: 185 all cylinders, +/- couple pounds. Leak down: <3% all cylinders, normal slight into crankcase. Starts smooth, runs quiet.
BUT--warmer the engine gets, more blue smoke out the tailpipe. Fully warm, goose her from idle: blue clouds. Total ~50 road miles and no change, so break-in doesn't seem to be an issue.
Turbo lines seem clean (but a possible source). PVC system possible--but could PVC blocked at any of the possible places be dumping that much oil into the cylinders?
We're stumped--appreciate any help, suggestions, thoughts.

Post by **JimBee** » 07 Mar 2016, 20:05

50 road miles doesn't seem like a lot. When I rebuilt my 850 fall, 2014, rebuilder told me to drive it normally for about 400 to 500 miles, then change the oil. Use dino oil for break in, NOT full synthetic, or it won't break in properly. No real hard acceleration until then. I was getting some blue smoke, too, for a while, but eventually it cleared up. Your compression rings are tight, but your oil rings might not be chafed in yet.

Did you clean up the cylinders thoroughly, wiping them out with engine degreaser on rags until they came clean?
Then ball honed the cylinders before putting it back together? If you don't do those steps, your rings might not chafe in properly.
Did you make sure all the ring breaks were set 120 degrees apart?

If you did all that, give it time, don't run it too hard, just run up from on ramps normally to a little spiritedly, to highway speed.

Post by **tryingbe** » 07 Mar 2016, 20:06

Was the turbo rebuild? Did you use a new catalytic converter? Have you check the play on the turbo yet?

RigsPGT · Post by **RigsPGT** » 07 Mar 2016, 22:24

The way I've broken in my engines is by starting them, getting them to normal temperature then right away its first oil change. Later on after cool off, start it, warm it and drive 50 miles before the 2nd oil change. During these 50 miles I vary the rpms but don't boost (either tie the wg open or install gauge and observe). Now the more miles you log by varying the rpms (no cruising) the more you up your rpms. At 200-400 miles the car sees 50-75% boost, also its nice to do another oil change.
Every time you run the engine, you have to have it cooled off and properly warmed up before any driving. At 1000 miles you should live into high boost

also allow the car to be in vacuum after bursts of wild runs.

Now this was the nice and easy break in procedure which takes time and patience with the right foot but I've also had success with beat the hell out of it right away (probably 20 miles easy varying the rpms and braking off of vacuum) then drive it like you stole it. I actually recorded maximum cylinder compression this way.

In your case, I'd say drive it more while breaking with vacuum which helps sealing the rings against cylinder walls. Give it some time but change the oil more often.

Post by **abscate** » 08 Mar 2016, 04:18

Give it some more miles, Dino oil, and vary rpms. Great project!!

docLocke · Post by **docLocke** » 08 Mar 2016, 07:14

Thanks for quick replies--and encourage/optimism.
Turbo is rebuilt. But as our local Volvo expert cautions: "Anything can go wrong with anything." Will double check, including intercooler.
Cylinder walls were cleaned, ball honed by first-rate local machine shop (who also did the head).
No cat. No muffler, either, 'cause nothing after downpipe installed yet. She's grandfathered out of cat requirement; whole exhaust will have to be custom. Holding off because it means large $s, tow or rollback to that shop, some miles away. Which explains limited road miles--each trip less'n our estimate of local blue response time to irritated neighbor call. We wish break-in the answer, but amount of smoke seems 'way beyond. Plus: start-up run is clean; smoke only begins as engine comes up to operating temp.

Our work on the head a cautionary lesson for other beginning rebuilders. I messed up the head gasket, we had to pull head, clean, reinstall. (Right: new gasket, bolts, etc.) Seeking a couple more hp on the cheap, this time we drop in the NA cams--not realizing/forgetting timing for these cams is set on #3@TDC, not #1. So we learn about interference. (30# compression; our expert: "your lawn mower's got more'n that.") Back to the recycler, we luck out, find another head. Machine shop calls next day: "new" head's too warped to plane, but the valves are good. We end up with one good head w/ clean valves/new seals; one warped head, bunch of bent valves. A little wiser.

Post by **chrafael** » 08 Mar 2016, 08:41

Have you done a spark plug check? It might tell you if it's one cylinder or all of them. Any base pressure might mean a cracked or incorrectly installed ring. If you think it may be the turbo, try looking in the hoses and see if there is a lot of oil passing through.

Post by **misha** » 08 Mar 2016, 08:55

Why you are replacing oil 2 times in 2 days and in 50-100 miles?????
One oil change after 800 miles after rebuilt is recommended,not necessary!
You're "braking in" engines in wrong way.

Post by **erikv11** » 08 Mar 2016, 09:50

docLocke wrote:... this time we drop in the NA cams--not realizing/forgetting timing for these cams is set on #3@TDC, not #1. ....

No offense but this sounds pretty confused and way off, makes me think that almost anything could be going on. Setting timing on these engines does not use TDC, it uses cam alignment (make them horizontal or use the sprocket marks) and the crank mark. Crank on the mark is close to #1 TDC but just shy of it. You must use the mark. For NA cams in a turbo block there is almost no difference; put the crank on the mark, then adjust the cams just a few degrees (i.e. ever so slightly).

docLocke · Post by **docLocke** » 08 Mar 2016, 10:32

Thanks chrafael: spark plugs not telling much of a story. Crank passes at least rubber glove test; will put a vacuum gauge on it this weekend, get more accurate reading. see if any change (eg) between idle and boost. And erik11: righto, of course. TDC on whichever cylinder sanity check only. Last round we set timing with proper cam tool.