Sd22 blowing tons of smoke

[Litty]

So I have a 1981 sd22 that was recently ran without oil on accident. The truck was making a knocking noise before I put oil in it. When I put oil in it the knocking went away but now I have a misfire and I'm getting lots of white smoke out of the exhaust. The truck is running rough it's all shakey and doesn't seem to idle right. When I rev it a bit it feels like it has no power and backfires. I think messed a ring up what do you guys think? 1981 Datsun 720 110,000 miles

[datzenmike]

The white 'smoke' is it perhaps steam? Smell it. I assume you are running antifreeze, does it smell like rad water?

[Litty]

I'm running antifreeze in my truck and the white smoke smells like fumes like something bad

[datzenmike]

This is why I'm asking. Fumes of what? Diesel, steam? Fart? Hot antifreeze coolant???? 

 

[Litty]

? I believe it's air/fuel mixture I'm getting some out of the blow by tube

[datzenmike]

Wayno, a member, is more familiar with the SD than any of us here. Maybe he can help.

[Litty]

Okay thanks ?

[millican]

The SD22 is supposed to shut down if it gets low on oil. Did somebody bypass that switch?

[datzenmike]

I forgot about this post, figured wayno would see it.

 

On 2/3/2019 at 7:58 AM, Litty said:

? I believe it's air/fuel mixture I'm getting some out of the blow by tube

 

Excessive smoking....

 

Is it over filled with oil? After running out? Hope like hell it's this simple.

 

 Have a compression test done to find if there is a low cylinder. Could have a hole in the piston, broken ring lands...

[wayno]

I wish I had seen this before, it doesn't appear that the guy has been back since Feb 3.

If he ran it out of oil then the oil squirters that spray oil up at the bottom of the pistons/cylinders went dry, this likely is not good.

The knock mentioned is not good either, I suspect it likely needs to be torn down.

When I over heated my Canadian engine it started blowing white smoke till the engine was completely warmed up, then it was not so bad, but it didn't even have the power of an SD22 after that and it is an SD25, one or more of the cylinders has lost compression and it is now not igniting/burning the fuel, First I would pull the valve cover off and and turn it over and make sure every valve is going up and down, at the same time you need to listen to the engine while it is turning over, does it turn over evenly or does it speed up and slow down, speeding up would mean one of the cylinders has no compression. slowing down could mean that maybe a push rod popped out and the valve is not opening.

The smell he mentioned is likely raw atomized diesel fuel, it smells bad.

As for the engine not shutting down from lack of oil, the engine likely had just enough oil pressure to keep it from shutting down as the oil sensor is real close to the oil filter/oil pump, I actually had to disconnect mine as the engine would not start with it connected, I have plenty of oil pressure, there is something wrong somewhere and I have replaced every component and have not had a positive result, I have 2 oil gauges in that truck as the stock 720 gauge was not reading properly, since I cleaned that side of the engine to fix all my oil leaks it now reads properly.

I suspect the engine will need rebuilt, most 720s with diesel engines look like crap and are not worth rebuilding unless the owner is attached to the truck, he said it had only 110,000 miles on it, so it may be worth rebuilding(expensive) or finding another engine for it(cheaper).

[Litty]

9 hours ago, wayno said:

I wish I had seen this before, it doesn't appear that the guy has been back since Feb 3.

If he ran it out of oil then the oil squirters that spray oil up at the bottom of the pistons/cylinders went dry, this likely is not good.

The knock mentioned is not good either, I suspect it likely needs to be torn down.

When I over heated my Canadian engine it started blowing white smoke till the engine was completely warmed up, then it was not so bad, but it didn't even have the power of an SD22 after that and it is an SD25, one or more of the cylinders has lost compression and it is now not igniting/burning the fuel, First I would pull the valve cover off and and turn it over and make sure every valve is going up and down, at the same time you need to listen to the engine while it is turning over, does it turn over evenly or does it speed up and slow down, speeding up would mean one of the cylinders has no compression. slowing down could mean that maybe a push rod popped out and the valve is not opening.

The smell he mentioned is likely raw atomized diesel fuel, it smells bad.

As for the engine not shutting down from lack of oil, the engine likely had just enough oil pressure to keep it from shutting down as the oil sensor is real close to the oil filter/oil pump, I actually had to disconnect mine as the engine would not start with it connected, I have plenty of oil pressure, there is something wrong somewhere and I have replaced every component and have not had a positive result, I have 2 oil gauges in that truck as the stock 720 gauge was not reading properly, since I cleaned that side of the engine to fix all my oil leaks it now reads properly.

I suspect the engine will need rebuilt, most 720s with diesel engines look like crap and are not worth rebuilding unless the owner is attached to the truck, he said it had only 110,000 miles on it, so it may be worth rebuilding(expensive) or finding another engine for it(cheaper).

My dad's pretty attached to and so i am considering that the truck has been restored will definitely be going the rebuild route. Any good rebuild kits you've seen other than cheap ones from eBay?

[datzenmike]

BTW it's pretty hard to run without oil on accident. These are not new cars that whine and complain about everything but they do have an oil pressure warning light . They need to be looked at regularly and checked. Oil and water....keep these monitored and topped up and you'll have very few problems.

[Litty]

13 minutes ago, datzenmike said:

BTW it's pretty hard to run without oil on accident. These are not new cars that whine and complain about everything but they do have an oil pressure warning light . They need to be looked at regularly and checked. Oil and water....keep these monitored and topped up and you'll have very few problems.

Mine did absolutely nothing, no light until is started knocking.

[datzenmike]

Um... it shouldn't get to that. You don't rely on the oil light to tell you you're low. Well, what's done is done and hope for the best. With just a little maintenance these engines easily go 300 to 500K miles.

[Litty]

Yeah I know just wish me some luck I guess hahaha

[wayno]

You should check everything first, all valves are moving properly and that it turns over evenly/even speed.

The idling rough has got me wondering, as I have had mine idle rough and it was because of a plugged injector, the knocking you heard could have been piston knock rather than a rod bearing as it went away when you added oil.

Does the white smoke coming out the tailpipe mostly go away after it warms up?

In the end I suspect you will either need to do a compression test if you cannot tell if it turns over unevenly, if compression is good on all 4 cylinders(turns over evenly) then it is likely something else, fact is the injection pump also needs oil(get it from the block) and if it went dry that could possibly be bad also.

Are you sure it was a knock, could it have been the cam and associated valve assembly rattling instead?

 

I bought a complete SD22 rebuild kit from that Falcon seller on ebay several years ago, it came with everything including the oil pump, but it was a 5 ring piston when I would have liked a 3 ring kit, but it appeared to run alright, I replaced it with a SD25 engine soon after so I really don't know a lot about how it ran long term, since then all the kits I have seen on ebay do not have the oil pump in the kits anymore, and that diesel engine is the only one I ever rebuilt.

I was considering buying that SD25 kit from China on ebay for a while, I asked them if they were 3 ring pistons and they said yes, I seen an SD22 kit that appeared to be from the same place but I do not know that for sure, and the kit was reasonably priced and I believe it had everything except the oil pump.

It is not cheap to rebuild these engines, if you do most everything yourself you can likely get it done for less, but unless you know how to remove and replace liners you will have to pay someone else to do that, and the head will need to be done also.

You also need to check the head, if it has cracks between the valves you will be better off finding another engine, there is a SD25 in New Jersey right now on ebay, there are places that sell good used engines also, but I have not searched them in a very long time now so I have no one to suggest.

[Litty]

It was definitely a knock and the truck gets up to operating temperature and it still has a misfire and a bunch of white smoke coming out of the tail pipe and blow by tube. I know it did have a rattle that was associated with the can but that was when i cold started it in the mornings

[wayno]

That misfire you have mentioned kinda baffles me, these engines use compression to fire after warmed up, if there is no compression the fuel should exit the tailpipe as weird smelling white smoke, it certainly should not be misfiring out the intake, I suppose it is possible for it to backfire out the exhaust, but I have never had either happen to me and I did overheat that one engine, it still ran, but blew white smoke out the exhaust, the photos below are what it smoked like after it was overheated.

 

 

If it is blowing white smoke out the blow-by tube I would suspect that at least one of the cylinders rings are shot and you will need to rebuild it or replace it with another diesel engine as one or more of the cylinders likely went dry because of no oil spraying the bottom of the pistons/cylinder walls.

You could also check out forklift places for engines/parts.

[Litty]

That's how mine blows smoke only if I could somehow show you a video of the engine running. Before all of this the engine ran perfect i drove it up to 90mph on the highway once now when when it's idling it is all shakey and doesn't seem to settle even when completely warmed up 

[datzenmike]

Do a compression test when warmed up.

[I'm BLUE]

I’m not a tech , however... I am  just a simple know it all trolololol. Everyone I’ve ever talked to about diesels....always refer to the injector system/oil pump (if driven off of). I know some guys will swap injectors as considered partial maintenance of the beast. I know a guy with a Cummins who had an injector puke and ruin his day as well. Idk.

 

seriously , a good verifiable used running/compression checked engine is hard for me to pass up. I was money ahead putting in a used compression tested Volvo engine with super high compression readings in then attempting to repair most of what was needed in my old one. Maybe your engines parts are or Arnt available.

 

my older Acura will do 85mph through Idaho/Utah/nevada/Vegas/Cali....while getting 31mpg all day long. Why are you driving 90mph in your Datsun diesel ?? Lol

 

either way best of luck. Make sure you conduct all appropriate tests , take good notes , and solve anything you can while it’s still together ! Don’t want an issue lingering around ruining a freshly machined chunk of metal. Idk 

[wayno]

Like I mentioned, I overheated that SD25 engine, it didn't start easy anymore and it lacked power, it smelt funny, and complete strangers were making comments when I started it.

I would find another engine if I were you, ebay, used engine places, and forklift places might have what you need and it is far easier to just replace the engine.

[Litty]

2 hours ago, wayno said:

Like I mentioned, I overheated that SD25 engine, it didn't start easy anymore and it lacked power, it smelt funny, and complete strangers were making comments when I started it.

I would find another engine if I were you, ebay, used engine places, and forklift places might have what you need and it is far easier to just replace the engine.

Will do, maybe I can find a engine on Craigslist....

[wayno]

I just looked in your area on craigslist and you hardly or don't have any Datsun or Nissan 720 trucks, let alone having a diesel truck being parted out, it is not looking good on Craigslist for you.

You may have to rebuild what you have, I didn't see any rebuild kits on ebay for the SD22, just pistons mostly, all you can really do is remove your engine and tear it down and see if it is worth rebuilding, it may have damage from running it out of oil that is not repairable, maybe the head has cracks between the valves/valve seats which would make the head trash/not worth trying to repair, but you know nothing till you take the engine apart.

I can see you putting thousands into rebuilding your engine and injection pump, a used engine is likely your best bet, I found this in a search, I know nothing about this company, it is what I found in a search, it said free shipping to a shop or commercial address.

 https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwiH5evf6OLgAhUpHq0GHb5KBk8YABAJGgJwdg&ohost=www.google.com&cid=CAESEeD2Zrg4KI11-jjnlHNu0Hsc&sig=AOD64_2mBYw3ldDoMBzw1TGw3ucjYBEX-g&ctype=5&q=&ved=0ahUKEwiLmubf6OLgAhVHu54KHVNgBOUQ9aACCIMC&adurl=

I found this rebuild kit in a search, it doesn't include a oil pump.

https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwiH5evf6OLgAhUpHq0GHb5KBk8YABAOGgJwdg&ohost=www.google.com&cid=CAESEeD2Zrg4KI11-jjnlHNu0Hsc&sig=AOD64_0brnjbhR2rb1u_vtHxKZuvCFzjiQ&ctype=5&q=&ved=0ahUKEwiLmubf6OLgAhVHu54KHVNgBOUQ9aACCJIC&adurl=

[datzenmike]

You'll probably get another low power smoker. If you want one bad enough rebuild it right.

 

I think the oil squirters are just for keeping the pistons cool and by extension the rings also... they are on gas engines but used on diesels it may be far different.  Loss of compression isn't coming back so  probably a re-bore and larger rings and pistons.