still smoking..

72maverick":1sl3diil said:
I've done 4 oil changes since break in and running 15w-50 I think and I've been on a few hour long drives changing rpms
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Good! I like a change not long after cam break-in...assembly lubes, etc. to get cycled...and then probably at least 2 more before first 500mi.

Sincerely not trying to 'bust your chops' or anything like that 72Maverick, but ~50mi on break in with a 'few' hour long drives :unsure:: Just want to make sure I'm not missing anything ;)

Is that "15w-50" diesel? (not a bad thought as that flavor can have more ZDDP. I like the heavier weight, 1st cause I'm in TX, and it's summer, plus tolerances are not as tight on these older engines vs modern, and then especially so on rebuilds (i.e. not factory tolerance). Another reason for sustained higher rpm 'ranges' for seating rings...but as bubba mentioned, incorrect assembly cannot be ruled out. I'd just be sure you gave thorough break-in allowance before critically evaluating compression measures.

One other thought, not intended to distract, how's your PVC system hooked up? I'll still suggest, don't panic just yet, and thorough break-in should complete well within the most modest warranty period, but something certainly could have been missed...I hope for your sake, it was not (y)
Good luck!

PS
Just noticed it smoking a lot when slowing down as well
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More noticeable at lower speeds, but also more reason to be sure higher rpm range break-in is thorough.

EDIT:
PPS You may have already checked, but removing the valve cover you should be able to visually verify condition and installation of these little boogers...
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I mean to pull it but it's been raining and the oil is diesel. The droves were about and hour and a half with speeds from 45 to 65. And I have just an oil filler cap and a breather. The pcv is not routed back into the carb. I wanted to hook it back up but the adaptor plate does not have a connection to route it back in. And the seals didn't look back before the assembly so that's why im wondering if the guides are shot. The first shop before the rebuild said guides were neede (they just did resurfacing). The second shop did a full rebuild and the shop has a very poor rep. So im wondering if they slapped new seals on and paintedand charge us.
 
72maverick":33ms1qla said:
The pcv is not routed back into the carb.
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Eureka! :D I'm gonna bet dollars to donuts that's most of your issue. The breather/filler cap is not sufficient to vent crankcase and evacuate the blow-by gasses, oil. Get that pcv routed back to the base plate if at all possible...or you could run a double element (full open like a draft tube...i.e. filter element at front and back of valve cover in the meantime, but best to get pcv routed to carb base asap). That could negatively affect break-in as well. I'd do this before getting to concerned about guides. I'm betting on a huge difference...after some additional break in with proper pcv setup, and crossing fingers for not long term negative effects to this point :nod: Good luck (y)
 
Frankenstang":16zoa9b8 said:
That could negatively affect break-in as well... and crossing fingers for not long term negative effects to this point :nod: Good luck (y)
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Not to overly concern you here, but long term sustained improper positive crankcase ventilation (aka circulation) can damage/prematurely wear out rings among other parts...likely here it has only prevented complete seating of rings (y)
 
How would you route it back. There are no openings in the adaptor plate or the carb for the pcv. I would like to do this. For the very short mean time, could I take off the oil filler and run the breather to see if it clears up any?
 
72maverick":ff4913nk said:
How would you route it back. There are no openings in the adaptor plate or the carb for the pcv. I would like to do this. For the very short mean time, could I take off the oil filler and run the breather to see if it clears up any?
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You could for a very short test purposes, but you'll likely see an ungodly mess...this would be what's been bypassing the new rings, but to answer your question, post a pic of the carb & base if you can. There's bound to be a correct base, and someone here who knows just what it looks like. Or worst case fab one.

In the meantime, rig up one of these at the front and back as soon as you can. Would not sustain your current situation (provided you have no draft tube). You could probably get requisite parts to rig a double filter system between the local auto parts & hardware store. Good luck (y)
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When im home I'll post the pics but the carb is a 32/36 Weber with the adaptor plate classic inlines offeres in the two piece set. I'm running the breather up front and for a while I was running one in the back as well and still smoked just as much. I will go back to that set up until I figure something else out.
 
72maverick":32v361as said:
When im home I'll post the pics but the carb is a 32/36 Weber with the adaptor plate classic inlines offeres in the two piece set. I'm running the breather up front and for a while I was running one in the back as well and still smoked just as much. I will go back to that set up until I figure something else out.
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Then I'd probably drill & tap adapter base if it or carb does not have pcv fitting provision. Two filter elements (front & back) is a poor substitute for regular pcv. You really need the pcv in the system routed to carb to create a vacuum assisted circulation of crankcase pressure & blow-by. Blow-by combustion gasses (burnt fuel) will acidify oil & cause premature wear on bearing and machined surfaces. Your extra oil changes have probably spared you long term damage, but incorrect ventilation of crankcase could prolong and/or prohibit rings fully seating. Hoping that's all it is ;) (y)
Yet another EDIT :D IIWIYS I'd probably still drop the oil once more after fixing pcv system and step up to a 30w to assist with limiting blow-by and trying to get the rings seated (can also add STP for ZDDP...I believe it still contains it), and I'll even suggest another 'cam break-in' style run after doing this. Not so much for the cam as for the rings, but 20-30 mins in the driveway varying from 2000-3000rpm, then follow it immediately with a decent drive...again just my $.02
Good luck!
 
Don't know if this means anything but putting a hand over the breather element area, I felt no vacuum what so ever
 
72maverick":38sck6ko said:
Don't know if this means anything but putting a hand over the breather element area, I felt no vacuum what so ever
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I'm assuming you mean the "breather element" on the valve cover. You should not feel vacuum there, as it's a positive pressure system not negative (i.e. suction/vacuum). Combustion gasses are forced past the rings from the combustion chamber down past the pistons and first into the main crank case or oil pan area. Even if you had a pcv hooked up at the rear of the valve cover you would not necessarily feel a noticeable vacuum on the oil fill at the front, depending on how tight the rest of the seals (e.g. gaskets like valve cover, oil pan, timing cover, etc.).

The pcv or positive crank-case valve 'system' improves on the earlier road draft tube system by utilizing vacuum (negative pressure/suction) from the manifold to draw out those gasses more completely, draw fresh air into the system, as well as recycling them back into combustion (thru the manifold) via a fitting at the carb base for more complete burning and minimizing pollution.
 
No sweat 8) I hope it doesn't turn out that they skipped valve guide replacement, or that you've got a problem with the rings.

Fixing up the pcv will help narrow down the problem and I suspect reduce your smoking measurably, if not eliminate it. Without good evacuation of crank case pressure, it will cause liquid oil to be forced back up past the piston & rings from the crank case/oil pan area an into the combustion chambers causing smoking...especially with new rings and limiting their ability to seat properly.
Good luck (y)
 
When you say "smoke" you mean out the tail pipe right?

Typcially if the exhaust is blue when the motor is under acceleration, it's rings. If it smokes during deceleration. it's valve seals.

A compression test should be done both "dry" and "wet". If the pressure increases significantly after pouring the oil into the cylinder it's bad rings. The oil will help seal around the rings and make the pressure increase. The oil doesn't help with leaky valves.

You can also put compressed air to each cylinder and listen to where the leak is. If you hear the leak coming out the carb the valves are leaking. If you hear it from the breather cap it's rings.

The PVC needs to be hooked up and evacuate the blow-by past the rings; even with rings that "seal" there will still be some blow-by into the crankcase regardless. Without a functioning PVC system you'll see oil/vapor come out of the breather and oil dip stick tube on a "good" engine.
 
well you'll have to pull the head to re-ring the block, so take the head to a reliable and professional machine shop and have them check the valve guides. I don't have the spec off the top of my head, but valve stem clearance is like 0.003" or similar. Its not very much and any side-to-side play is usually too much. good luck!
 
No offense to mugsy, but pumping compressed air into the cylinders and listening for leaks (aka 'leak down test'), won't ID bad guides if the valves are solid, clean and seating.

Unless I was not following along correctly above, this is a rebuilt block with head that's 'reportedly' had a valve job (given 72Maverick may have some misgivings as to the reputation of the head shop).

EDIT: I think it's premature to say you need to pull the head, re-ring the pistons, and have the head redone again. Unless I missed something...i.e. the suggestion to not panic ;)

I strongly recommend giving the break-in suggestions I gave a shot. They don't cost more than a oil change and the time to get the pcv online correctly.

I really doubt, given the low mileage on this rebuilt engine, that you've toasted the "new" rings even with the pcv not setup, but again I do think it could be prohibiting complete seating of the rings.
Just my $.02.....Good luck (y)
 
I'll do the pcv first. Makes the most sense and it is affordable as of now. I things don't change, I shall go back and rethink the problems
 
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