bought a 920 cat, engine seized 20 min later.

[Labrador-tractor]

well I bought a 62k series 920 that is a bit of a fixer upper. engine was weather seized when I bought it and I had full intentions of pulling the motor and inspecting it as soon as I got it home due to not trusting the work done on it in the past. story is they installed a new crank, bearings, seals and rings. on startup the engine knocked! pulled oil pan and found a rod got missed with the torque wrench.... tightened that and all was good. times got busy with that company so poor 920 got drove outside the shop unfinished and sat a year or more. they went to start it to move location and it was stuck, not having tie to play with it they pushed it on the float with a komatsu and hauled it off at the storage yard with another. there it sat for several more years until I came along.

Day 1 I show up rock the motor with a bar a little bit and it turned 360 with very little effort, great I thought! Day 2 I grab some new batteries and try firing her up. I would get smoke but no fire, turns out the rack was stuck so I pulled the governor and worked the rack until it was free, by this time its dark out. Day 3 I show up and she fires up! sounds great, has great oil pressure, builds air, hell the brakes even worked! I run it around the yard a bit and everything was great so I say I might as well drive her home. its a 1.5 mile drive from the yard it was in to my house via dirt road so I figured that should be no trouble.... I made it less then half way home and she locked up with very little warning. I get out for a look and see oil dripping, look up under and see no drain plug. I walk about 100 feet back and see the oil splat with the drain plug sitting on the ground. so after forgetting to tighten the rod nuts they forgot the drain plug!!!! so I get the tow of shame home behind a volvo.

pulled oil pan and found #3 rod spun and seized.



had loader floated to my cabin where it will live and pulled motor this weekend.



pulled crank tonight.



stuck crank in lathe and cleaned up #3 rod journal, got all the bearing material off with some 320 and was still on the upper end of spec for size.

 

[Labrador-tractor]

I thought I was good to continue polishing until I seen this, seems I got some heat checking when the bearing failed. not sure now if this crank can still run as is, or if it should be ground or if its now a boat anchor.

 

[OzDozer]

That crank needs to be ground to get rid of that heat checking.

 

[Labrador-tractor]

figured I had little to loose and ground into the crank with a die grinder, got in around 20 thou and still can see the crack. smallest bearing I can find was 50 under so unless that crack disappears in the next 5 thou, which I doubt it would, this brand new crank with 30 min run time is now a boat anchor.

I have a parts loader, a guy many years ago started to swap a 950 engine ( same 3304 but with a turbo) into it but life happened and he left town. sat long enough the plastic over the turbo rotted away and rain got in. So it is seized as well. hopefully in the next week I will get it hauled out of the alders grown around it, pull the motor and inspect the crank. the "parts" loader actually looks better shape then my "running" loader. If I knew the transmission was still healthy I'd consider making it the running loader. but the starter was robbed off it so thats a 3 inch plus hole opening the transmission to the world and its moisture.

hopefully the crank is good, if not it looks like I'll be doing a 3RD cummins swap on a loader. I helped a buddy in 2010 put a 5.9L in a john deere 544, was a straight foward swap not much maching to get the torq bolted to the flywheel. Then in 2019 me and a buddy did a Cat 910 / 4BT swap, I posted that build here luckily the 920 looks to be a much easier swap, I already have a 4BT here in my inventory I can use.

 

[Dave Neubert]

you can get a used crank for not a whole lot of money or even go with a after market one i have never had problems with the aftermarket ones

 

[Labrador-tractor]

you can get a used crank for not a whole lot of money or even go with a after market one i have never had problems with the aftermarket ones

trouble is where I live, look up Labrador city in canada, rather small area with 1 dirt road between me and the rest of canada. finding something local used isn't going to happen unless I buy the 930 off the same company I bought these 2 920's from, which has crossed my mind honestly. there is no engine shops around here, no scrap yards (there is a company that takes scrap metal but wont sell you anything) and not much for parts suppliers for this type of thing. its a mining town so most of the companies around here make good money and just go to cat or komatsu, pay the bill and don't think twice.

I might go to cat and get a price on a crank from them if my other one is junk to. seen some online but shipping to here is usually crazy expensive for something this heavy.

 

[Labrador-tractor]

found out today about a 950 headed for scrap, never sized it up but some steering stuff broke off, wheel was pointed to the left at a 30 degree angle. so I figured the motor should be good enough to get the crank from. its a d330 so not many common parts.








started pulling apart the motor, #1 rod was loose.... pulled the cap and found this.




so I have another crank that is no good! I sure hope that 3rd engine in my parts loader has a good crank. I wasn't fond of cat engines before I bought this loader, now I'm starting to really dislike them....

 

[Coaldust]

My goodness, shame on the mess. You got a good collection going now. Love the service truck. Keep us posted.

 

[Labrador-tractor]

the d330 is going to a new home tomorrow, I have a friend with a old 944 that surprise surprise has engine trouble haha. its burning a lot of coolant so maybe just a head gasket but maybe more. so I'm gifting him this engine for parts.

Thanks! the ole 75 has been a good truck, its a bit of a johnny cash special. started life as a 2wd , 390 gas, C6 auto and it had the "ton of rust" option as well. I deleted the ton of rust on the cab, installed a 5.9L cummins and eaton 6 speed from a 98 F800 I had. converted the eaton to Over drive. dodge divorced NP205 transfer case. Chevy Dana 60 front and 14 bolt rear ( i was going to build a 1980 GMC K2500 before I got the ford but wanted the extended cab, figured I'd use the axles I already had) used the chevy steering box, front shocks , brake lines etc. rear is an air ride setup I built using school bus air bags ( the 5.9 has an air compressor) and ride height valves with a dump option. the deck was supposed to be temporary as i had it laying around but now that the truck is usable its not high on the priority list to build a nice deck. the Hiab 027 knuckle boom went on just a few years ago, the honda runs it for now. I do have a PTO for the eaton but the pump is WAY to big to run the Hiab, when I find a smaller pump I might reinstall it. but honestly I like the honda, its more quit then the cummins.

 

[Coaldust]

Holy cow! I had a feeling there was something special about it. What a cool rig.

 

[Labrador-tractor]

found some pictures of building the ole truck.

 

[Labrador-tractor]

finally got my parts loader dragged out of the tree's and got the engine pulled out today. it was also a 950 engine like the last one but in a 920 after the original motor piled up some parts in the oil pan. I'll grab that motor as well when I can, its pretty buried in they're shop right now, they tossed it down in the service pit in the floor and there is a long term project truck parked over it.



plastic over the exhaust rotted away years ago so it was drinking rainwater.



one of my buddies said ill soon be like a nascar pit crew but only for cat engines haha.



draining the oil and ice from the engine.

 

[Labrador-tractor]

crank looks good and bearings are decent. #2 main bearing had a score in it from something passing trough but the crank itself is decent. I'll polish it up and call it good enough at this point.



#2 piston wouldnt push all the way up into the cyl so I pulled it out for a look. it was clearly the one doing the drinking!

 

[Labrador-tractor]

started putting the motor back together tonight after work. pretty much have it done other then the rear. tomorrow I will back the 75 F250 in and use the hiab to upright the engine again. my engine hoist really does not like when a 3304 over centers until the chains bring up again!



put the crank in the lathe to clean up #2 main a little, took very little to get it to a pass in my books for a old cat that will see at best 50 hrs a year.




the new mains never got hurt when the oil plug fell out so I reused them. the 950 mains had some wear.



'new' crank installed, I used the 950 rod bearings that were with the crank. I was surprised to see they were actually in very good shape. probably last my lifetime with the amount of use it will see honestly.



everything installed that can be installed in this orientation, besides the fan and hub that will wait until engine is upright so I don't bend the fan flipping the engine.

with any luck the rear main seal will be in at the cat dealer on friday and engine will be installed this weekend.

 

[Welder Dave]

It must be nice to have such a well equipped shop.

 

[Nige]

A suggestion to make sure to time the balancer shafts correctly or you’ll be looking at another low-hour engine failure soon after installation.

 

[Labrador-tractor]

Thanks Welder Dave, been Buying tools all my life so its building up nicely, trouble is now I am running out of room to use these tools haha. I actually have a 15 foot lathe I ended up removing from the shop. the use it got wasn't worth the space it took up. I plan to build a 40'x60' shop at the cabin where the 920 lives and the Big lathe will get setup there with a kubota running it is the plan.

Thanks Nige, timing should be good I done it as per the CAT manual pinning the shafts with the flats up and #1 at TDC. also lined up all the timing marks on the oil pump gears while I done it. both methods agreed with each other so fingers crossed no more failures with this engine.

I've done 2 others (one was a D330 but close enough) in the past that are still running good, But I will admit I am rusty on these, last one I was in before this adventure was 2010.

 

[nicky 68a]

A very good read.
Keep us updated please.

 

[Labrador-tractor]

A very good read.
Keep us updated please.

glad you liked it the read. I really wish I had videoed the whole experience for my you tube channel but at the time I was thinking it'd be a non event drive home. boy was I wrong lol

no phone call from cat today for the rear seal so it either didn't come in, or more then likely it is here but hasn't made it through receiving and the warehouse yet. I wouldn't be able to do much with it anyways, rolled my ankle pretty good yesterday so not very mobile at the moment.

 

[Labrador-tractor]

not much progress on the 920 this weekend but I did get the flywheel housing , starter and fan back on. while I was moving it around I decided to weigh it seeing I couldn't find a weight online that was correct. In another thread on here I seen that Cat says its 3800LBS on SIS, they are not even close...





Thats with everything on the motor besides the air cleaner , muffler and oil in the pan.