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  #1  
Old 05-15-2014, 01:15 AM
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Back fire and miss fire.

I just finally got my car on the road and it started to shake really bad and is making a weird sucking noise at idle. It's also back firing at higher RPM's under load. There's a ton if white smoke and it doesn't go away when warm. Is it possible I lost my timing on the injection pump and it would cause this? It was running great until about a hour of road time. Now it won't idle for poop and dies out quickly.

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84 300sd 2.47 dif 360k
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89 civic hatchback auto 140k
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85 300d with unknown knock. driven over 30k with knock and still going. sold for $800
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  #2  
Old 05-15-2014, 01:39 AM
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I didnt know diesels could backfire... what does that mean to you?

I think your estimate is a good guess, but you will need to give us more information.

First check: pull the vacuum pump and inspect the bolt that holds the timing device to the injection pump shaft. If this backs out, the IP will lose timing to the crank and cam when the woodruff key shears (or smushes, or plows through the dinky timing shaft)

"..[back] on the road..." -what did you do to the engine?
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  #3  
Old 05-15-2014, 01:53 AM
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I agree on the no Backfire on Diesels.

White Smoke can be Coolant or atomized unburned Fuel and you can often tell by the smell.
Sounds like something is causing a misfire.

Some big Air leak can cause a misfire.
A Headgasket issue can cause a misfire. Look up the symptoms of a bad Head Gasket in the DIY Section.

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Try doing the Injector Cutout Test. To locate the bad Cylinder. If you find a bad Cylinder swap the Injector from that Cylinder to antoher cylinder and see if that Cylinder now has the problem. If the problem follows the suspect Injector to the new Cylinder it ias a bad Injector.

Try Changing the Fuel Filters. If that does not work get long length of 5/16" Fuel Hose a Container with clean Fuel draw the Fuel from the Container instead of the Fuel Tank.

Are you sure the Sucking Sound is coming from the Front of the Car. If not your Tank Vent could be restricted.
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  #4  
Old 05-15-2014, 04:30 AM
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Trust me it's a back fire. I believe the diesel is going into the exhaust and combusting in the exhaust manifold. The head gasket is brand new and I've not lost any coolant. The smoke is unburt fuel not coolant based on the smell. The weird thing is it did this before we hit the road but stopped when I removed all the hard lines and turned it over to clear then out. I thought it was air in the lines and sucking noise was a mystery. Now I'm not sure. I removed the injection pump and installed it based on the Haynes Manual. It didn't say anything about fine turning. Just to line the timing marks up and put the motor at 24 btdc.
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84 300sd 2.47 dif 360k
26 mpg needs lots of love
given to me in pitty

89 civic hatchback auto 140k
33mpgs soon to be low to mid 40's
been in the family since mile 1

85 300d with unknown knock. driven over 30k with knock and still going. sold for $800
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  #5  
Old 05-15-2014, 08:25 AM
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Location: Charleston SC
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If it ran great for an hour and then began misbehaving, something has worked loose, and my bet is something associated with the injection pump.
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'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC
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  #6  
Old 05-15-2014, 08:54 AM
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Something came loose in the exhaust system causing partial blockage and the backfiring is oil/carbon sludge in the exhaust igniting?
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  #7  
Old 05-15-2014, 08:55 PM
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So I did a quick advance and it ran much better. No smoke less not no miss fire. And it was cold. But I haven't diven it.
__________________
84 300sd 2.47 dif 360k
26 mpg needs lots of love
given to me in pitty

89 civic hatchback auto 140k
33mpgs soon to be low to mid 40's
been in the family since mile 1

85 300d with unknown knock. driven over 30k with knock and still going. sold for $800
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  #8  
Old 05-16-2014, 02:27 AM
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Quote:
Originally Posted by benzdude42 View Post
Trust me it's a back fire. I believe the diesel is going into the exhaust and combusting in the exhaust manifold. The head gasket is brand new and I've not lost any coolant. The smoke is unburt fuel not coolant based on the smell. The weird thing is it did this before we hit the road but stopped when I removed all the hard lines and turned it over to clear then out. I thought it was air in the lines and sucking noise was a mystery. Now I'm not sure. I removed the injection pump and installed it based on the Haynes Manual. It didn't say anything about fine turning. Just to line the timing marks up and put the motor at 24 btdc.
Haynes Manual or not the splines are fine on the Drive end and it is easy to bump or twist the IP during instalation.

Also the Timing Marks represent the begin Injection on #1 Cylinder when the IP was new.

As the IP Camshaft and the Tappet Pins and Rollers wear the begin the Begin of Injection can change.

If the 1985 Car has a 1985 Fuel Injection Pump it has the Port that the Timing Locking Pin will fit into.

Using that you would have needed to line up on 15 degrees after top dead center of the Compression Stroke.

The locking Pin would prevent any inadvertent rotation of the IP Camshaft during installation.
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  #9  
Old 05-16-2014, 03:00 AM
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I put it in at 24 btdc. I had a friend check it out before we timed it it and he said that the back fire noise wasn't explosion, but most likely the noise of the uburnt diesel going through the values. It was smacking really bad like I had pored oil into the intake. But we ran it for a minute with no miss fire or weird noise before I had to head to work. I'm planing on finishing it tomorrow morning. Hope this fixes it.

__________________
84 300sd 2.47 dif 360k
26 mpg needs lots of love
given to me in pitty

89 civic hatchback auto 140k
33mpgs soon to be low to mid 40's
been in the family since mile 1

85 300d with unknown knock. driven over 30k with knock and still going. sold for $800
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