I am purchasing a '78 Cat 920 loader that has been sitting for 7-8 years. Its a 62K 9xxx serial number. It has a 3304PC engine in it. It comes with the famous story of "ran good when parked". The engine is now seized up. I'm sure there are no miracle cures, and it should just be bought with the thinking of doing an out of frame rebuild? Is this the approach you would take? Any insight is appreciated. Thanks.
Guess it all depends on what you have in mind for this machine. If just wanting to use it for a few hours a year I might suggest one thing. If you are planning on using it close to 40 hours a week and not wanting to have it quit at a bad time then maybe would suggest something else. Also it depends on what kind of facilities and skills you have to be doing the work or if you will be hiring it out! You appear fairly new here with only 22 posts so if I was to say keep it away from a dealer in Minn. whose name starts with a "Z" you might not understand. I see you location is shown as NY, where abouts? Give us some more details about you and it's job you have planned and I'm sure you will get some good suggestions. PS Might want to look over this thread, I know it's not a 920 but the same basic engine in it guy did a lot of work on, just scroll past the parts on the tracks and track adjusted and other things you don't have! HeavyEquipmentForums
Yep, rebuild and have a reliable "no surprise" engine.
Ran good when parked. Did it move and operate good, or just run? A good question to ask. Has the exhaust been covered? Open and rained in for 10 years? How many hours? What kind of shape is the rest of the machine in? That normally gives some pretty good clues about how the machine was serviced and taken care of. Good Luck.
And if possible how about posting some pictures, you'd be amazed what some people can spot in a picture or two!
Here are a few pictures. I'm in western NY. We have the ability and tools to do the rebuild. Realistically, the loader will only be used occasionally to load bank run gravel and topsoil into my single axle dump for small odd jobs. I'd probably use it for snow removal as well. At scrap price, I can't see how I'm going wrong.
And a couple more details. It belonged to an older gentleman who got sick and passed away. I am into it for a little more than scrap price, but not much. Right rear tire is flat. I was told by the grandson that the head had been redone, but at that time the machinist had recommended planing the block as it wasn't in spec. The owner, not wanting to pull the engine just "gooped" up the head gasket and used it as is. My thought is I will find antifreeze in the oil and that may have contributed to the seizure (since the exhaust is covered-albeit only by a rain cap). What do you think? Thanks.
These machines are called money pits I've never heard of planning a 3304 block. If they cobbled a head gasket what else ? Bob
Well if the block needs the deck planed it would need to come out and some one who knows what they are doing would have to recut the counter bores. Not a big job if one is set up to do it. If you have the place to work on it preferably under cover I guess it would not be that big of a waste of effort to pop off the head and see what it looks like then if you are not scared at that point pull it out of the machine and get deeper into it. I'd hold off on buying any parts till it was down to the bare block and the machinist has looked at it. Snow in western NY? Hard to believe, I thought it all ended up north of Syracuse! Just this last Sunday we woke up to white stuff coming out of the sky. Did not stick as the ground was too warm but still did not like seeing it this late in April!
I doubt the engine is stuck real hard. If the engine oil isn't way way overfull (from coolant leaking into the oil) I would concentrate on getting the engine free and running to make sure everything else is going to work before I would start dumping money into the engine. Heck, for an occasional use machine, that head gasket 'fix' might last a long time.
That's kind of along the lines I'm thinking. What would the preferred method of "unsticking" the engine be?
As bam1968 says first thing to check is oil level to see if there is coolant in there. Might want to crack open the drain and let a little drip out, if there is coolant in there it should be obvious as it will be at the bottom. If no coolant in oil pan next to check would be the cylinders. Take fuel lines off and remove the nozzles, believe it takes a 15/16 or 1 inch socket on the top of prechamber to get them out a 3/4 inch wrench to remove the fuel lines. Once the nut is off the nozzles should pull out with the adapter. Once all them are out try turning engine over to see if anything comes out. I would suggest covering the fittings on the injection pump the fuel lines come off to keep dirt and crap out of the pump! If it won't turn I think I might begin by dumping some penetrating oil in each cylinder through the hole the nozzle can out of and let it set for a couple days. Then with the nozzles still out try turning it over. If you can get good access to the front of crank try turning in both directions. If you need a better description of any of this let me know and I can try for more details or even pictures!
Thank you, kshansen. I think I understand everything you have said. My only confusion is the adapter that you speak of. What do I need there? Thanks again.
Guess my terminology is a bit off according to Cat. Open the attached file and under the heading "Install Fuel Injection Valves" what I was calling adapters they are calling "body" #2 in picture and what I was calling nozzles they call "valves" part number #3 in the picture.
Oh perfect. Thanks for taking the time with that. I really appreciate it!
just another idea, you could pull the exhaust manifold and check for water intrusion into an exhaust port which is easily done on a non-turbo engine. it looks like the muffler goes straight onto the exhaust manifold and after long periods rain can leak past the rain cap especially during a wind. nothing beats a tin can or pail (as long as it doesn't rust through) over the exhaust. if no water has leaked in maybe it is dry seized just from condensation in the cylinder over the years- not probable but remotely possible in northern areas that have a season with ambient temperatures below freezing
Yes, agree that is a very good idea!
Acetone and transmission fluid mix at 50/50 has been a preferred loosening agent in stuck antique Cat motors for years. Remember though, not all engines come loose. You have nothing to lose by trying though. Some have also used a porta power pump to push heavier oil into a piston that is up to get things moving. Just make a adapter for the injector port. You may have to remove the rockers to insure the valves are shut. May be a little drastic but again if you need to tear down otherwise it might be worth a shot.
Well I got 3 gallons of water out of the oil pan drain
Guess the oils not perfect. How much oil was there left? If it was pure water, no antifreeze, it might still free up. If it's antifreeze, why bother?
I got maybe an ounce of antifreeze and then the water. As soon as it was draining what looked to be pure oil I put the plug back in. When I checked the dipstick it was right where it needed to be at that point.
Does anyone have a service manual for it?
I did the hydraulic method on a mack six once. Only problem is the only thing I had available to produce the pressure needed was an air powered grease pump. Wish I had a camera on that truck once it was broke loose and I had a loader give it a push with injectors out. Grease snake shot at least twenty feet in the air when it came out of the injector holes! Thinking back on it these days I probably could have filled cylinder with 30 wt oil before putting the grease in. Good news is that truck ran pretty good in the quarry only using a bit more oil than normal!
Yes, I have a service manual
I had a 1952 Northwest Dragline that was stuck last year. It had a Cat 8800D with a pony motor. It had been stuck for atleast 6 years. I pulled the injectors and mixed up transmission fluid, acetone and a gallon of Kroil. Filled the cylinders and covered them up. It took 2 months but I checked it one weekend and all of the cylinders were empty. You could turn it over with a 1/2 " drill motor. It amazed me that thing started and ran very well. Patience is the key in this situation for sure.
Thanks for the insight, guys. I am going to try and move the machine home, and into my shop this weekend. I will go the route of acetone and trans fluid- and then wait. I'm sure I will have more questions to come. Can I just put this thing in neutral and push it on a trailer?
You will need to release the park brake. Our 920 is equipped with a valve stem on the bottom of the air tank. I don't know if it came from the factory that way or if it was added later. Basically you will need to get some air in the tank to release the park brake. (FYI the air tank is under the radiator). You could also back off the adjustment on the park brake if you don't have access to air. I'm guessing since at least one tire is flat that you will have access to air one way or another. FYI it doesn't take much air to release the park brake.
If not running it will not matter what position of the shifter is in. Looking at SIS it looks like this machine has air over hydraulic service brakes and a spring applied parking brake on the driveshaft(think Maxi-brake if more familiar with trucks). The best option I can see would be to position the trailer in line with the loader so you don't have to deal with trying to steer a non-running machine. I'm picturing you pushing it backwards on to the trailer so that what ever machine you are using to push will be pushing on the bucket of the dead loader. To get it off the trailer if you have someway to lift the bucket with controls in float the slip them into hold it might hold the bucket up to make unloading a bit easier and do less damage to the trailer. If the hydraulics won't hold the bucket up might need to use some blocks to keep it up. Just be safe if getting near a suspended load!!! Now for your original question getting it to move. The safest thing would be if you have a way to air up the air system that way you would at least have the parking brake to stop the machine and with a bit of luck the service brakes might actually work. A portable air compressor of some kind would be nice or a jumper hose from the truck that will be pulling the trailer all depends on what is available. If you have electricity near by even a little pancake compressor would work. I deally getting that flat tire aired up would make the job much better.
Ok thanks so much, again. The plan is to take a portable compressor to air things up- including the flat tire. We will take the dresser 510 loader with to lift/push. Back at the shop we have lots of equipment, so we should be able to unload without much issue. I’ll let you know how it goes! I also got manuals ordered today.
Don't forget to get some pictures of the Dresser pushing the dead Cat on the trailer. That should be good for some comments from the Cat people!
lol! I'll be sure to! Thanks again!
I got the 920 back to the yard. I hired a landoll trailer to move it. I also found that the muffler had rusted out, and that's where all the water came from. Also got the head pulled. Here is the damage. Pics include loading out of the 920, steering it with the dresser 510, back at the yard, water in the exhaust, and pic of the head removed.
last one
Looks like time to be pricing some cylinder kits . Not sure about working room under a 920 engine but did a few 966C engines in frame 3306 version of your engine just two extra holes to fill. As I understand the 3304 does have balancers down inside that need timed when installed. Like I mentioned before if you have time to skim down through this thread Nitelite did the 3304 in his 951and it might give you some help on yours. HeavyEquipmentForums Did you get the service manual from Bam1968? That is one of the important things I always liked to have for a machine. If you need some spec's or information right now I can access much of what you might need on SIS.
Yes, thanks Kshansen. I've been reading over that thread and its very useful. Looks like plenty of room under the 920 to do what needs done. Do you suppose the aftermarket liner kits available on ebay are good quality? I'd really like to get "loaded" liner kits.
also, I did get the service manual. I'm waiting on the parts book. Do you have the correct piston part # so I can look up kits?
Looking in my parts book... it shows 8N3181 for part number for piston group. Hope that helps
Any chance you have the complete S/N for the engine just to be safe? But for a start looks like there is a good chance the piston Number would be 8N3181, a little more digging seems to indicate that number changes to 8N3180. Not sure if that first number included the rings as the 8N3180 says it takes a 9S3068 ring set. But to be safe I would see about what the full S/N of the engine is, actually there is a chance you can find a part number stamped on the pistons you have. It is often stamped on the top of piston. I thought I had posted this last night but see it was not sent?
numbers:
Yes, I forgot that you had posted that picture! The part numbers I posted are the correct ones for that 7N1515 according to SIS as of today. The original ring group was a 7S9404 but back in 1983 they changed the top ring material and the new ring group is the 9S3068 number. There appear to have been several other versions of the piston part number but the 8N3180 is the latest that they list. They do show the 2506563 as the Yellowmark part number which I guess is a different form of the "Cat Classic" line of parts. Just for fun I checked Milton's price on the two piston numbers: 8N3180---$198.94 2506563---$78.45 Or at least that is the price I'm seeing on SIS
Great info. Thank you. Are you comfortable with the quality of the kits listed on ebay? In frame kits are in the $600-800 dollar range. I appreciate the prices from Cat. I think I'll be purchasing a kit rather than just the individual parts if that makes sense.
I'm sorry but TBH I wouldn't trust anything I could find on eBay as far as I could throw it....... YMMV. Have you tried talking to the good folks at Offroad Equipment..? www.offroadeq.com Lots of posters here swear by Offroad prices & service. If you do speak to them don't forget to tell them that you were sent to them by HEF.
You will have to know which bearings you have before you order .Call Cat and price their classic kit ,bear in mind Cat has the same warranty on all their parts and you will need parts not in the kit .Consider with local company ,Cat or otherwise they will want to help you with your problems and likely have people who have actually seen one of these engines. Good luck Bob
Ok. Thanks for the insight, guys. Your experienced opinions definitely help the inexperienced such as me! I have gotten a price from offroadeq. Right now I'm looking at a CTP (costex) premium kit with rods and ready to drop in sleeves for around $900. Thoughts on this kit??
I have no knowledge of this kit but one thing you do need to check no matter what parts you use in the liner projection and condition of the counter bore in block for the liner flange. Not sure how much of that is in the manual you have. I attached some of the information below. Note they refer to the "cat official tools" but there are other ways to measure this it just takes a bit of imagination. One easy to use option is: https://www.amazon.com/Central-Tools-6434-Sleeve-Counter/dp/B000OQHR9W Which is in my opinion better than the Cat tool.
Well, guys, I am pretty disheartened to report this (and quite embarrassed as well) but I really messed up on this one. While pulling the oil pan, I quickly realized the real reason this machine was put out of service. Somehow I completely missed the rod poking out of the block on the cylinder closest to the cab (#1 or #4?) I really don't know if the widow that I bought it from intentionally misled me, or had no knowledge of this problem, but it really doesn't matter anyway. I inspected it, and just totally missed it. I know the picture isn't the best, but I think you get the idea. There is nearly a perfect circle poked out of the block. I believe the area is non-structural and could be plated. Is it crazy to think this? What are the odds that the crankshaft is salvageable? Does anyone have a lead on 3304 short block for this without spending a fortune? Are different serial numbers/arrangement numbers/part numbers critical for finding a used block since I will be using all of my bolt ons? Thanks for the help...and go easy on me!
Here is the pic.
Ouch!!! I feel your pain. It looks as though it had the engine side panels on it and it can be difficult to see behind them so I can see how you could have missed that. Hopefully you will be able to find another block for a reasonable price. I have heard of guys patching them up but have never tried it myself.
Yes the engine side panels were in the way. That's what I'm going with anyway lol!
Being you are in Western NY I might give this outfit a call: https://www.hrparts.com/ Or this place near Syracuse: http://businessfinder.syracuse.com/s-s-tractor-parts-inc-marcellus-ny.html
Ok. I'll give them a call. Thanks. My block part number seems to be 2P8774. The commonly advertised one is 1N3754. Do these interchange, or is this 1N3754 for a spacer plate engine?
Okay here is what I find:
Wow. You are a great help! Thanks for the information. That will make shopping much easier. It sounds like there is no sense in buying the updated block unless it comes with the head, rocker assembly, thrust washers, etc.
Yes! that's why I felt it was best to just post the full service bulletin instead of just saying it was the spacer plate replacement block.
You might drill it with a hole saw. and tap it for a big pipe plug or use a cleanout plug with the recessed square hole. We fixed a 4-53 block this way once with a 2-1/2 inch pipe plug. It was behind the starter where a rod came out when a sleeve broke at the intake ports. Just threaded it and gooped it up with JB weld when we screwed it in. No big loss if it does not work. You may need a metric hole saw to get the size close enough to tap. A little sloppy thread is OK if you use the JB weld to seal it.
Another idea I have seen used to patch a hole in a block where it was not really a critical structural area. Just take a piece of say 1/8 inch aluminum a bit bigger than the hole and form it to fit the contour of the outside of the block then start with one hole drilled and tapped into the block and fasten it on and drill another hole about one inch away and tap and fasten that and keep going around the hole. This way you keep everything lined up. Then remove plate and clean area real good and use JG Weld or sealer of your choose and reinstall plate. It may not look pretty but if only a limited use machine could save a few thousand a replacement block would cost.
Great ideas guys. I really hope they can help someone, and I'll definitely tuck those methods into my "bag of tricks". However, this block is definitely a goner, unfortunately. I got it apart last night. There is a crack going up from the hole, and the rod hit one of the balancer shafts which cracked and broke the corner off the block as well. This one is a boat anchor. Is there any reason this one won't work? https://www.ebay.com/itm/Caterpilla...rentrq:6e5cc2361630aad71666485dfffebc94|iid:1
Just looking at that one in the pictures it looks like it has been stored outside in the weather. Looks like rust on every surface. Also it may be just old gasket and cracks in the paint but the area circled in red below has me worried: I would want to get a very close look at it before deciding to go for it. The amount of rust on what I see really would be a turn off. Top of block and counter bore areas as well as the bores for the main and balancers looks very rusty.
Well, I got a good deal on a remanufactured CAT block with the correct casting number on it. It is on its way. I have my crankshaft at the machine shop getting cleaned up. I'm sure I will have many more questions coming soon, such as how to properly time everything from scratch. Thanks for the help.
Do yourself a favor and buy a service manual for your machine ,you will need it. Bob
Thanks, Bob. I did buy a service manual and parts book. They will definitely come in handy. Sometimes guys on here, such as yourself, put things in more understandable terms. It also helps, at times, to hear tips, tricks and insight from folks with more experience on certain engine or machine.
When I'm installing the cam bearings, balancer shaft bearings, mains, and rod bearings should I use a particular assembly lube or just 15w-40 engine oil?
Joel59, Just as a favor to anyone trying to help include your S/N either in the message asking a question or I believe there is a way you can put it in so it shows under avatar over to the left of the message box. You may have posted it before but some people maybe replying to several different posts and little things like that can help alot. Good luck and if you need any clarification on something I will try my best to translate from Caterpillar to English, or what we here in NY call English! Nige and a few of the guys from Australia might disagree that we have a common language!
If you know you are going to be finishing the job fairly soon motor oil would be fine for me. But if there is a chance this will be an extended project in spare time I might be tempted to buy some assembly lube from an auto supply shop. One example: https://www.autozone.com/miscellane.../lucas-oil-4-oz-assembly-lubricant/692400_0_0 Another one that we did use a lot: https://www.oreillyauto.com/detail/...iplate-motor-assembly-grease/l0034094/4419698
I used to use a lithium grease called lubra plate, it doesn't run out if you don't fire up sight away, but mixes with oil.
I use "STP" or "Motor Honey".
Hi guys. I'm just wondering if I've already messed up, and am going to have to retime this engine from scratch. The crankshaft has been removed and one of the balancer shafts was broken off when the rod went through the block. Left assembled are the injection pump drive gear, injection pump idler gear, and camshaft. Should I just grind a mark on those where they are now, or is everything goofed up now with the removal of the crankshaft, oil pump, oil pump idler, and broken balancer shaft. Thanks.
Not 100% sure of the question. There should be timing marks on all the gears that need to be timed, like the cam gears and the balancer gears. Not sure on the fuel pump timing. Tried to check what is used but would need to know the S/N of the engine to be sure which injection pump system you have. Not sure if it is timed with a pin in the pump or if it uses the tool that locks the drive gear in time. Just to be safe give the S/N of the engine the fuel system you are using is from, I would assume this is the original loader engine fuel system.
Thanks, Kshansen. The engine serial number is 78P41378 arrangement# 7N1515. It is original to the 62K9517 loader.
Also, I realize my question was not that clear, and I apologize. I guess I'm just having nightmares about timing this engine once I get it all put back together due to reading all kinds of posts about timing issues. I am worried because I couldn't nicely line up any marks before disassembly due to having a badly bent up and broken rod through the block and broken balancer shaft. I have my reman block and am getting ready to pull out my old cam and injector pump and gears.
You time it when you put the timing gears back on. You can do whatever you want to it at that point. There should be no problem at all if you can find the timing marks, they're correct, and you have the correct procedure. People get into trouble when they pull an injection pump or something else and don't have the timing gears visible. You're starting from a blank slate, much easier to verify everything is right.
FWIW I would take a paint pen and mark the timing marks on the balancing shafts. They can be hard to see when you are laying underneath there trying to get the oil pump bolted up while lining up the timing marks on the shafts. Since you are basically starting from scratch your situation may be different. In my case, we had a guy overhaul the engine but didn't time the balancing shafts so I had to pull the pan and time them. I just remember having a hard time finding the timing marks. Just my $.02
As others have replied above timing should not be a problem when you get to reassembling things. If you don't have that information I will try to provide it if no one beats me to it! As for the injection pump timing check on your original engine fuel pump and governor the cover that the throttle control arm shaft stick out of there "should" be a bolt in the position shown in the picture below. I colored the head of it red and circled the #1. If you see that bolt on yours remove it and if I'm right it will actually be a couple inch long dowel like end on it. Don't worry nothing will fly out! That is actually a tool you use to time the pump to the engine. Let me know one way or another there might be an easy work around if your engine does not have that tool. work aroun
Wow that 920 Is a blast from the past when Cat was a different company and I worked at the dealership. Dumb simple and no plastic! I kind of miss it! A previous life. 910,920,930,950,966,D7G all the real deal. Well if memory serves correct the 910 was a Mitsubishi. 40 years ago. Where did the time go? Things were different.
Good luck with that old gal she was great for her size in the day.
Ol' tctractors could put a few verbs together to describe the timing procedure. It's really easy to time them with a service manual in front of you. I think I could still do it without one, but I couldn't tell you all the steps without being there to look at it since it's been over 10 years since I did the last one. I use Lubri Plate as well.
Thanks for easing my mind guys. This is going to be my first diesel rebuild. Kshansen, yes, I do have that bolt. I haven't removed it yet, but it is there. I, too, miss tctractors. Everytime I look at my old block with the hole in it I can hear him say "that is really Knackered" lol!
Hello guys. Finally getting the funds together to order parts. Do you see any issues with this kit? https://www.ebay.com/itm/3304-8N318...861675?hash=item464fe114ab:g:jf4AAOSwR5dXQ8OL My parts book says that the piston group part number is 8N3181 and this kit is listed as 8N3182. Is it correct? Thanks again. Joel
Anybody know if this will be the correct kit for me? Thanks
Well I’ve hit another snag. My “remanufactured” block has a very obvious flaw! Do I ship this thing back and start the search for another one, or have it repaired at their cost? What are your thought?
I would get another block. if that is the quality of their 'remanufactured' block, there is no telling what else is wrong with it. the whole thing could be a nightmare
Send it back and on their dime.
What the ..... did they do to that block, drop it of a cliff? No way I would try to fix that. I mean if it was the last know Cat block and it was only going to be used for display in a museum then maybe! What did they use to stamp those numbers in the block a drop ball from a 100 foot tall crane?
Ok, so I'm ready for some help timing this injection pump to the engine. The accessory gear (on the inj.pump) never got marked to the idler gear that mates to the cam. How do I go about timing this correctly? I'm including pics of
insert pin in the flywheel thru the proper hole in the flywheel housing and at the same time the hardened timing pin should drop into the recess in the injection pump drive(under the oblong cover on the injection pump). always turn the engine in the direction of rotation so the backlash in the gears is removed as you come up to the timing holes.
Well you need to get all the front gears on first, don't forget the balance shafts need to be timed too! Did you find the timing pin I mentioned back in post #74? You need that to time the injection pump. I'm attaching the timing instructions from SIS to give you a start if you need more information ask and I or someone should be able to help.
Thanks for the timing information. I will be using it shortly. I have received my new oil pump and pickup tubes, and now have those installed. What should I be doing to prime this pump? Is there something I need to do while I have access to the pump, or do I need to put the pan on and filter and turn it over manually to start pumping oil. In short, I think I need to prime the system, but don't want to put it together too far to do so. Thanks. Joel
If you lubed the parts as you assembled them about the only thing I might do to the pump is dump some clean oil in it and turn over by hand before installing it. Then fill completed engine with oil and crank it over with the batter till the oil pressure gauge starts to move up before letting it start. Should only take a few seconds. If engine has a spin-on oil filter might help to fill that before installing. New oil pump should self prime fast.
Ok, great. Sounds like I'm on the right track. Thanks again. Now I just need to come up with the front (small) seal installing tool. I have the larger rear one.
I can’t seem to find which cylinder is #1. Is it closest to the flywheel or closest to the timing gears? Thanks
The timing gears, it can be confusing at times with the way engines are installed in some machines! Most companies think of the front of an engine is the end away from the flywheel and the right and left of the engine as if you were standing at the flywheel end and looking towards the opposite end. So with most rear engine installations the "front" of the engine the at the rear of the machine and the right side of the engine is on the left side of the machine. Clear as mud huh? I say "most" as if you are ever lucky enough to work on a Cummins VT1710 V-12 engine you will find the left bank of the engine is on what 99% of the world would think is the right side of the engine! Try doing a tune-up on one of them at 2:30 AM after starting work at 7:00 AM that same day! BTDT!
Thanks a million! Now it makes sense why I got the wrong balancer shaft!!!!