Lister D crankshaft

Managed to sort the flywheel after a struggle!
I ordered crankshaft sleeves and big end bushes for both my engines, thought i'd have a go at replacing them. Replaced sleeve and bush on one crank and conrod to put into my running D and then refurb crank and conrod from running D for new renovation (hope that makes sense). Any way took running D to bits and changed everything over (managed to change conrod over without removing piston), few hours later I started the D, OMG!! it sounded like Lister diesel, ran it for 30secs at most. Took the crankcase window off to have a look, all I could see was that the machined faces on crankshaft and conrod were about 1/8 apart. Took it to bits again to see what else was going on, nothing obvious apart from the gap between the conrod and crankshaft. Checked to see  if I had put the wrong gudgeon pin in(worn one) nope that was all good! Put it all back together and Lister diesel again!! 1/8 gap again, that's not right!
Got the other crankshaft and conrod ready, took a while as the phosphor bronze bearing needed a lot of scraping!  All back together and sounds like a D should.
I've not had a proper look at the crankshaft or conrod to what is wrong with them. My only thoughts are that the conrod that I used may be slightly bent or  twisted! I had a long and frustrating day, but on the bright side, I had my own gas up in the garage, had the D going for about an hour with the doors open!
Any ideas what would have caused the diesel sound and gap!
Look forward to hearing from you!

Some pics to show partial strip down of engine and bushes

Just curious but is there a hole in the new bearing which aligns with the hole on the top of the conrod housing to allow oil to run into the bearing and is there a channel which sits opposite the splasher hole to allow oil along the bearing I've always had to drill a whole though.
I'm also surprised you had to scrape the bearing as I've never had to do that on these bearings, also there is a certain amount of side play to let the conrod find its place.

Maryalice

Hi, there were holes in the new bush at the top and one for oil splasher, no other holes. The hole didn't line up very well at all, I had to re drill and then remove the burrs very carefully.
I had to scrap both bushes, one more so than the other because I could only just about get it on the sleeve, took me ages to scrape it to get it to rotate smoothly.
I know there is room for side to side movement, but each D that I've had the conrod has always touched the machined face on the crank. I will put a straight edge across the conrod (small end to big end) to see if there is a slight bend in it.  It's possible that the conrod came out of a seized engine and someone has tried to free it up and ever so slightly bent the conrod.

Sorry I confused you, you reminded me that mine didnt align either so had to re drill them but as I said mine were a good fit with no need to scrape.

Maryalice

I've never scraped bearings before, just have to be very careful!

68jcb wrote:Managed to sort the flywheel after a struggle!
I ordered crankshaft sleeves and big end bushes for both my engines, thought i'd have a go at replacing them. Replaced sleeve and bush on one crank and conrod to put into my running D and then refurb crank and conrod from running D for new renovation (hope that makes sense). Any way took running D to bits and changed everything over (managed to change conrod over without removing piston), few hours later I started the D, OMG!! it sounded like Lister diesel, ran it for 30secs at most. Took the crankcase window off to have a look, all I could see was that the machined faces on crankshaft and conrod were about 1/8 apart. Took it to bits again to see what else was going on, nothing obvious apart from the gap between the conrod and crankshaft. Checked to see  if I had put the wrong gudgeon pin in(worn one) nope that was all good! Put it all back together and Lister diesel again!! 1/8 gap again, that's not right!
Got the other crankshaft and conrod ready, took a while as the phosphor bronze bearing needed a lot of scraping!  All back together and sounds like a D should.
I've not had a proper look at the crankshaft or conrod to what is wrong with them. My only thoughts are that the conrod that I used may be slightly bent or  twisted! I had a long and frustrating day, but on the bright side, I had my own gas up in the garage, had the D going for about an hour with the doors open!
Any ideas what would have caused the diesel sound and gap!
Look forward to hearing from you!

Took the crankcase window off to have a look, all I could see was that the machined faces on crankshaft and conrod were about 1/8 apart. Took it to bits again to see what else was going on, nothing obvious apart from the gap between the conrod and crankshaft. Checked to see  if I had put the wrong gudgeon pin in(worn one) nope that was all good! Put it all back together and Lister diesel again!! 1/8 gap again, that's not right!

The  con rod bush protrudes on on one side and is flush on the other side of the con rod if fitted correctly. When refitting the con rod the flush end should be put on first and fits against the shoulder on the crank pin. The large oil drain hole in the big end bearing is refitted at the bottom to allow oil to drain back into the crankcase. Source Lister D book 68/734, later versions may differ slightly. I can't find my later book, do you have one Martin ?

Wil look this evening.

Thank you for the info!   I have over the years pulled a few D's apart and put back together, but never had this issues. Going to have a look at the conrod in a bit to see if it's slightly bent.

I've put a straight edge across the conrod(small end to big end) and have found that the conrod is bent, 2mm out of true. Have tried 2 other conrods and several straight edges, all lead me to the same conclusion.... it's bent!  Will now try to remove the bush from the conrod carefully and use another conrod.

Removed the bush from the bent conrod and installed it in to another one. Have spent the day rebuilding another D with replacement conrod, Have turned the engine over many times by hand,and keeping an eye on the conrod, it seems to be where it needs to be and no strange noises.
I must confess that I normally work in MM and not inches, so when I said 1/8" gap, I should have said it was 4-5mm and looked to see what that was in inches.
Looking forward to getting this D running and passing it on to a new owner.