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  #16  
Old 09-20-2020, 10:26 AM
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Quote:
Originally Posted by HughO View Post
... It was 1 deg BTC but I indexed it and put it back in and set it to 24 deg BTDC...I cranked it this am and still wouldn't start...
Did you make sure that you were 24 btdc on compression stroke(#1 cyl)? because if it was 24 btdc on exhaust stroke then it surely won't run.

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  #17  
Old 09-20-2020, 12:11 PM
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Quote:
Originally Posted by Diseasel300 View Post
Uhh......That doesn't sound great. Where are you seeing the blowby? Typically the engine should be running to generate any meaningful blowby, even on a very tired engine or one with stuck rings.

Thanks for your replies everyone. Mist is coming out of the breather cap/valve cover when cranking. I poured Parts cleaner(Berryman) in the cylinders to try to soak the rings overnite. only 2 cylinders held oil for more than a few minutes . The levels dropped fast but none held oil for long. Seems like the Berrymans going straight down into the sump. Probably stuck rings I guess. Turning the engine over with the crank pulley seemed a little too easy early on which made me uneasy. It was as easy as a gas engine. It wouldn't fire even with ether while cranking. I pulled the injectors and the tips were heavily carboned and a few of the injector parts were rusty. 2 nozzles were discolored. Terrible sign which I assume could be SVO caused damage?? I wonder if there is any hope. I did a spray pattern check and one injector was just a stream,one had a crappy sideways pattern and the other 2 were less than perfect but functional. Pressures were 1700 with 3 and about 1300 with one. If my guess is SVO caused damage I wonder if I am at the end of the line. Any ideas on freeing stuck rings besides parts cleaner? If the injector has rust I assume the injection pump might have rust. Putting in new rings is too much of a job with these old diesels I think. I have put new rings in my toyota corolla over a weekend with the engine in the car and it was a simple job. Am I looking at a used engine?
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  #18  
Old 09-20-2020, 06:33 PM
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Waste vegetable oil burners can be bad news.


Personally if the car otherwise looks good you might consider trying to locate a good used engine. Depending on where you live and some other factors. It may not be that expensive.
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  #19  
Old 09-29-2020, 01:12 PM
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Quote:
Originally Posted by Sugar Bear View Post
If compression is low, yes a ring soak may and often does help. I'd try soaking the rings for days with occasional movement of the crankshaft. That engine has a rope rear main seal which could easily be damaged by solvents in the oil, I'd avoid cleaners added to the oil only soak them from the top.

I wasn't crazy about my HF tester.

Good luck!!!
Well, thank you in advance for your advice. To recapitulate My 240 D has 102K miles and the previous owner put in a new timing chain and after that it wouldn't run. No other info. I went over it and the valves were way out, the timing was way off(ie 1 degree BTDC). I set these to spec and pulled the injectors. they had very poor spray patterns so I put in 4 new nozzles and fixed that problem. I was worried about sticking rings because the injector nozzles had terrible carbon buildup and cleaning them released a orange thick scum which I guessed to be veggie oil? There was also corrosion on some parts. Once reassembled with 4 good nozzles I soaked the pistons for a week with lacquer thinner and MMO. Finally I decided to order a compression tester(should have done that first!!) The numbers were 95,90 ,80 and 80. Compressed air came out the intake manifold after setting the #1 piston at TDC. Bad sign. What happened? My guess is that the previous guy screwed up the TC installation and then cranked it over bending the valves? Any ideas from the resident geniuses on this site? If I need a valve and head job is there advice? Like reusing head bolts, putting in new guides etc? Any other ideas to be sure this is the problem? If this car wasn't in cherry condition I'd throw in the towel. O rust, O dents, good seats.
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  #20  
Old 09-29-2020, 08:55 PM
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Sounds like removal of the head is next. If the cam is timed right. The blowby coming out the oil filler hole while cranking. May be stuck rings with wvo usage or scored cylinder walls.

I am wondering about his need to replace the timing chain as well. It should have not broken or been worn at the claimed milage. I would check the serial numbers to see if it is the original engine. Or the odometer reading is way off. That is not unusual with the 123s.

Waste vegetable oil residue can turn with sitting to a very strong glue in piston lands. Head work like many other things is not particularily cheap now.

A decent used engine checked out properly before purchase may be financially the easiest way . If you remove and install it yourself.

I am not a resident genius incidentally. Regardless of what the wife claims.
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  #21  
Old 09-30-2020, 02:20 PM
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Cam towers will break before valves will bend.
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  #22  
Old 09-30-2020, 10:20 PM
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Engine oil while using WVO does become sticky if not changed frequently. I was wondering about gummed up valve guides. Polermized base oil is known as a result of burning WVO. The valve faces could also be in a mess. Observing the valve train while rotating the engine by hand might be a move.

To me there is just a little too much going on with that engine. What an owner does with their car is up to them. Someone dealing with the consequeces or aftermath of what they did can be another story

Bent valves if present should be stopping the ability to rotate the engine. You mentioned the valve lash was way off.. Far too loose or far too tight? Far too loose could be valve face buildup of some sort. Or the owner did this. Normally these engines lose valve lash clearance never gaining it.

I personally have some negative bias about burning vegetable oil. Perhaps honestly acquired. Back in the day people would post problems they were having. Without mentioning the WVO they were using. After awhile if the problem was not typical. I asked them what they used for fuel. When they fessed up it became easier. Sometimes it took a lot of time before they admitted it.

Like most members we try to help other members. We are fortunate in having some really knowledgeable guys on board. I am but an greenhorn in comparison. The really sad part to me was they thought they were using free fuel. Many of the ensuing nightmares proved otherwise.

Last edited by barry12345; 09-30-2020 at 10:56 PM.
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  #23  
Old 10-01-2020, 11:22 AM
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Quote:
Originally Posted by barry12345 View Post
Sounds like removal of the head is next. If the cam is timed right. The blowby coming out the oil filler hole while cranking. May be stuck rings with wvo usage or scored cylinder walls.

I am wondering about his need to replace the timing chain as well. It should have not broken or been worn at the claimed milage. I would check the serial numbers to see if it is the original engine. Or the odometer reading is way off. That is not unusual with the 123s.

Waste vegetable oil residue can turn with sitting to a very strong glue in piston lands. Head work like many other things is not particularily cheap now.

A decent used engine checked out properly before purchase may be financially the easiest way . If you remove and install it yourself.

I am not a resident genius incidentally. Regardless of what the wife claims.



I guess the next step is head removal. The previous owner did not say why he replaced the timing chain and I should have asked him. The fact that the timing was way off and the valve adjustment off suggests to me the possibly the chain broke or slipped a cog. I assume if the chain broke the cam assembly would have been damaged. It appears just fine. A friend who is a cummins mechanic agrees with me that the valve(valves) may be bent nut not so bent that the engine can't be turned manually. So I will pull it and take a peek. I ordered a borescope and will try to see if I can view the valves thru the manifolds. Obviously can't thru the injector holes. I am looking for a used motor or head but they are few and far between in the mountain west. No one drives rear wheel drive diesel cars out here because of the ferocious cold and heavy snow. Even carpart.com has very few.A wrecked and running car is probably my only option. I have rebuilt a few motors but these old diesels look more difficult than what I have tackled before. The common notion that they last a million miles is nonsense unless they have had meticulous maintenance. I have several cummins trucks with a gazillion miles that still run with much less maintenance and 40-50 yr old tractors that still run almost like new. I do love the generally excellent engineering of these W123 cars and think they should never be scrapped unless they are rustbuckets but at some point it becomes a point of diminishing returns trying to find old serviceable parts and even new parts. I have out one AT and one engine in these cars in the past and it is an easy and fast chore compared to some modern cars and trucks so I guess I will stick with it for a while longer. I do have a restored 300D which now runs flawlessly but these 240D cars with their taxicab simplicity appeal to me.
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  #24  
Old 10-01-2020, 10:45 PM
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You likely have a broken timing shaft.

This shaft is responsible for driving the Lift pump from the chain movement

and keeping the injection pump timed to the engine crankshaft.

This is why the previous owner took off the vacuum pump... to get a look at the bolt behind the injection pump drive gear.

He probably gave up to due to the complexity of taking that gear off of the IP timing shaft. There is likely a stripped out press fit pin holding a timing chain guide below the vacuum pump, which you will discover some day.

best wishes.
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  #25  
Old 10-01-2020, 10:49 PM
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the shaft I am talking about goes from the injection timing device - driven by the chain - all the way through a bearing in the block where it meets up with the injection pump.

to replace this shaft, you will need to pull the injection pump and the vacuum pump
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  #26  
Old 10-01-2020, 10:57 PM
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You are likely to find a sheared / mangled woodruff style key and a cracked shaft at the thin end near the bolt that holds it to the timing device.
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  #27  
Old 10-03-2020, 10:39 AM
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Put a 240d engine wanted add in our parts wanted section of the site. Something may turn up. Within a reasonable distance.


If you are going to continue. There was a reason I asked if the valve clearances where far too tight or far too loose. Far too loose may be signifigant.


I also found your compression readings where odd. All cylinders read about equally very low. Personally I might want to check if the crank pulley indicator really corresponds with top dead center on the number one cylinder.


The easiest way would be to remove the injector and bring the engine a small distance from from indicated TDC. Fill the cylinder with oil. Best to rig a straw as a guide. Rotate the engine the oil level in the clear straw or tube will very accurately indicate TDC. Then check the pointer. Since you do not know why the chain was changed or if they had the engine pulley off. A waste of time perhaps then again you have some strange things.


On the other hand the current situation may just be a result of burning WVO. The residue in the rings has gone solid with time. Plus the valve faces are a built up mess. What I am suggesting otherwise is a long shot.


I just got to thinking what if this is a true low millage engine. If so it would be wrong to not check every possibility out. Even if unlikely. another thought is if the past owner burnt a lot of questionable WVO. Plus the combustion was poor. A more or less equal buildup of by products of the WVo that did not burn. Got built up. This could account for the similar compression readings. Even the excess valve clearances.
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  #28  
Old 10-03-2020, 11:00 AM
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Had equally low compression readings, it was the gauge. Numbers that even are a good sign, numbers that low if accurate are not; however, the low could be due to valve timing. I'd follow barry12345's advice and be certain that the piston is at TDC and then/next confirm the pointer is at zero, then/next confirm the camshaft is lined up.

Every adjustment (except valve clearance) on that engine relies on an accurate TDC pointer, if it is off so are the other adjustments. If it's off it is like building a house on a sloped foundation...

Good luck!!!
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  #29  
Old 10-10-2020, 11:06 AM
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Quote:
Originally Posted by Diseasel300 View Post
Uhh......That doesn't sound great. Where are you seeing the blowby? Typically the engine should be running to generate any meaningful blowby, even on a very tired engine or one with stuck rings.

Well I finally
+ received my compression tester and the numbers were terrible, between 70 and 90. All the air was coming out of the intake manifold. Perhaps exhaust as well. Crankcase was quiet. This was a lot of trouble for little yield. My guess is bent valves c/o the previous owner's screw up. So now it's up to me whether to pull the head and take a look see or retire it to the back of the lot as a parts car. A used motor is a possibility of course but the brake system is totally shot from MC to all 4 calipers. At some point it makes sense to call it quits. But no rust and no dents and only 100K miles makes it worthwhile...........except for the durn transmission is an automagic. If it were a manual.......maybe.
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  #30  
Old 10-10-2020, 11:35 AM
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I would put an engine in it and fix the brakes. You have nothing to lose because it is worth very little as is. Throw $1,000 in parts and you'll have a nice, serviceable, comfortable, interesting car to drive.

I'd be thrilled if the only issues on my cars were engine and brakes. That's the easy stuff. Body work gets expensive and fixing all of the little stuff takes time and can cause frustration.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. Probably up for sale in the fall 2020 still have it. 85TD beginning to repair to DD status. Waiting on shop to do minor but more than I can do rust.
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