82 720 z22 motor constant white smoke

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ok so i've been fighting with this 82 datsun 720 kingcab 4x4 ever since i bought it, vac lines and emissions previously ripped out, hitachi carb was junk, the engine compartment was a mess and then after i sorted all that shit out, threw a brand new weber carb and fuel regulator on it... it started smoking, constantly! the smoke was white and so bad it could not be driven. the funny thing is it ran great, just smoked like a chimney.
it was pretty obvious that it needed a new headgasket and of course some of the intake bolts n exhaust bolts broke. unfortunately i was broke after taking the head to a machine shop to check for cracks, cleaned and pressure tested i couldn't pay for them to remove the three broken bolts... so i assembled everything started it up and same thing, tons of white smoke! i realize some of the bolt threads in the head run into water jackets. now could this white smoke be caused by coolant leaking out of the broken bolt hole and into the intake then burning up or am i thinking incorrectly? one more thing since putting the new webber carb on it should i bump the timing up?

 

any help would be appreciated, thanks!

[hobbes_the_cat]

Not 100% sure about the Z motors but on an L head the coolant could get into an intake runner if the gasket leaked, I would assume the same could happen on a Z motor. If I have just one bolt loose on the intake there is usually problems, if you have three broken ones it's a recipe for disaster.

Another thing, you mentioned checking for cracks but just as important is checking to see if it is still flat. A warped head with a new gasket will leak just as bad, right away.

[datzenmike]

This is a Z22 motor then? Carb on one side exhaust on the other?

 

None of the manifold bolts go through into the water jacket.

 

Driving it with white 'smoke' was the wrong thing to do. This is water and it runs out and the head over heats and warps. There is a very good chance of a warped head and no gasket change is going to cure this.

 

Next time take the head off with the manifolds attached or at least the intake.

[datsunaholic]

if you have broken manifold studs on the intake side, it's going to leak coolant into the intake ports.  They have to ALL be there are torqued right.  With a NEW gasket.

 

 

 

i found this when disassembling a Z20 that the prior owner cheaped out on and tried to reuse the manifold gasket after slathering it with orange RTV.  I got it as a seized engine, though what actually happened was #1 and #2 cyls were full of coolant from the now excessive leak and it was hydrolocked.   it also wasn't torqued right, since the RTV squeezed uneven. Usually it's not that extreme, it'd just blow steam like a 19th century locomotive.

 

 

And Mike is correct, if the head is warped, a gasket isn't gonna fix it.  it'll just get worse, until you REALLy warp the head.   Another Z20 I got had a head so warped you could slide a quarter under the middle when it was on a flat surface.  Can't believe the cam didn't seize or break.  That was from driving it 30 miles after the radiator ruptured.

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forgot to mention i had checked the head with a straight edge and also told the machine shop to check if it was square they said it checked out fine. also only drove the thing a block or two once it started smoking, then shut her down only starting her after reassembling the head with news gaskets. today will be taking the intake manifold off to try to easy out the broken bolts... if unsuccessful will then remove the head, again :/ is there a possibility the intake is warped or needs resurfacing? i'd hate to waste another intake gasket and the labor if the intake is also in need of surfacing. wish i had the time, money and a decent workshop for this job ha. thanks for the advice folks!

[datzenmike]

There are coolant ports in the intake runners. It bolts are broken and it's not sealed, the water will get sucked into the motor. Intake gaskets are cheap. Make sure both surfaces are clean of of gasket, put them on dry. (no sealer or gasket goo)

[Stoffregen Motorsports]

The biggest problem with running an engine like this is that when coolant sits in a bore, on top of a piston, it rusts the rings to the bore. Even if it is very slight, the rust eats away at the surface of the ring and the bore. In the short term, the bore can handle it, but the ring will eventually fail. In the long term (if the motor was let to sit for a long time, like a month or longer) the ring would weld itself to the bore and when broken free, the ring would be completely junk and the bore would have noticable pitting in it requiring an over-bore and new rings and pistons.

 

Not a good idea to run a motor like this.

 

If you decide you want to fix it, but don't know when you'll get aroud to it, drain the coolant then pull the plugs and crank the motor over to get all the coolant out of the bores, then spray WD40 or even oil into the bore, crank it again and then re-install the plugs.

[LenRobertson]

So how about clever tricks to get the broken bolts out? So far I've been lucky and haven't had to mess with removing broken bolts from aluminum. I hope I'm just scaring myself, but I get the idea if the steel bolt is stuck in the aluminum hard enough to break off, it is really stuck. Stuck so that just drilling and using an easy-out will result in a broken easy-out. Does soaking for days with PB Blaster help loosen? Moderate amount of heat with a torch? Is welding a nut onto the broken bolt safe to do next to aluminum?

 

It just occurred to me I have a W53 peanut head with one stud that isn't broken, but looks bent and I'd like to replace. I've Blastered it and tried to unscrew using double nuts, but it isn't breaking loose.

 

Len

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luckily the bores appeared fine after removing the head, didn't see any pitting or damage so i'd hope the rings were fine. there was far too much smoke for it to be the rings with the motor still running as good as it is.

while living in the midwest i had absolutely no luck with easy outs but here in arizona with the lack of humidity i've thrown a little heat on the surrounding metal with a torch and had an easy out work well enough... i'm hoping with the aluminum i should only have to heat it a little and back the broken bolts out... if not then? is there another method i can try? or is it's back to the machine shop with as much change as i can scratch up :/

[datzenmike]

Al expands twice as much as steel when heated. The hole actually gets very slightly larger when heated. Never had an easy out work... ever. 

[nerdistmonk]

Al expands twice as much as steel when heated. The hole actually gets very slightly larger when heated. Never had an easy out work... ever. 

 

i got lucky when i had to take my exhaust mani off, all the bolts were only finger tight. 20 seconds later....well that was nothing to it. (my truck has a habit of working all its nuts and bolts loose)

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had only a couple easy outs work... a good drill and retap worked for me in the midwest. no harm no foul as they say and if the easy out does not work and i don't think i can get my hands on a welder, i'll just have to remove the head, again. so is there anyone that knows a number i can cross-reference with autozone or oreillys for a timing chain holding tool? 

[LenRobertson]

I'll try a bit of heat on my stuck stud. I've had easy-outs work sometimes, but usually only if Blaster has done its job. If a bolt breaks on tightening and the threads are properly oiled, using the corner of a very small chisel to catch the face of the broken piece and unscrew it with hammer and chisel works quite well. But this doesn't work on a really stuck one. If the bolt can be heated so it is actually free to turn, then an easy-out should be okay.

 

I think at least some machine shops use an EDM machine to safely burn out broken bolts, although it has been a few years since I read about that so I may be thinking of another process. "Home Shop Machinist" magazine had a series of articles on making a EDM, but I recall it was rather involved to build one. Anyway if a machine shop charges a lot to remove broken bolts it may be because they are using a specialized method.

 

Here is a timing chain wedge thread with drawings to make your own:

http://community.ratsun.net/topic/41595-timing-chain-wedge/

Amazon shows a "Nissan timing chain wedge", but out of stock. eBay #290771123213 appears to be one. I couldn't find any on the Autozone site, but my search skills are poor.

 

Len

 

 

 

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whew was off throwing my 68 satellite together and doing some work on my 83 t-type trans but finally going to get back to work on this poor ol' datsun... btw thanks for the previous help folks!

so after putting a new head gasket in it still smokes like it did before. i'm thinking the shop i took it to didn't properly check the head, possibly the head bolts are stretched or maybe my intake manifold is jacked up :/ this time around i'm going to make sure i get it to a good shop and i'm going to take the intake in with it make sure they both have good mating surfaces... problem i'm having can't find where to get z22 head bolts, been searching for hours???? anyone know where?

[ggzilla]

It still smokes because it had nothing to do with the head gasket. You should determine what is causing the smoke.

[datzenmike]

Was it using coolant? Was the rad always low?

 

This time of year all cars have a white steamy exhaust because of the cold.

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the old head gasket was bad as it showed leakage from the a water jacket to piston number one...

yes it uses coolant but i see no evidence of oil in the coolant, it smokes like a chimney :(

any know about those head bolts? 

[datzenmike]

Water in the oil is more likely as it gets pushed past the rings.

 

I assumed the bolts were like the L series and totally re usable. There is nothing in my FSM saying not to.

 

Both head and block must be absolutely clean. Gasket mounted dry. Bolts tightened in three stages in this pattern to 20 pounds...

 

R A D

8....7

4....3

2....1

6....5

10..9

 

Same pattern to 40 pounds and last the same pattern to 60 pounds.

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yea nothing in my hanes book about it either but just always feel comfortable with new headbolts after a swap or gasket :) from what i remember the head and block were pretty clean, i'm kinda ocd when it comes to that stuff and that seems like the order and torque specs i went by. of course it's been a few cars and many different torque specs since i put the head back on lol but i for sure followed what was in the manual.

[ggzilla]

Z-series head bolts are reusable. They are not the new TTY (torque-to-yield) bolts.

[ggzilla]

Double post oops

[ggzilla]

Yes your head gasket needed replacing. But what is causing the smoke? Is it oil smoke, coolant smoke, or water vapor (normal) smoke? Under what conditions does it occur? What shade of white is it?

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not exactly sure it wasn't smoking when purchased and didn't start smoking until after a weber carb swap... i'm starting to suspect the previous owner to have dumped some block sealer in there because upon draining the rad it was all water and thinking the block sealer finally gave out but hoping it's not the case. it's definitely coolant with huge white plumes of smoke, looks just like a head gasket let loose and because of only water in the rad it smells of an old wet sock. smokes under all conditions and starts about 5mins into running it. before i give up the ghost on this engine i want to make sure it's not the intake manifold because there was a broken bolt in the head from the previous owner and this time around i'm going to have a machine shop take care of it along with the other broken bolts the guy left on the exhaust manifold side, plus clean up the mating surfaces if need be :/

[ggzilla]

To test if the block has a crack or hole in the cooling system, use a cooling system tester. Pump it up and see if it holds. If it doesnt, listen with an ear hose to pinpoint the leak. Better not to guess with this kind of problem.

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good call, just realized i could probably rent one from autozone. thanks