CAT 955K TURNS over but wont run.

[Themaskman72]

Counting them from front to back, (1) was very tight, (2) is the one that the center section screwed out of instead of the whole thing, (3) was loose, (4) was very tight.

 

[Nige]

Let me guess, #3 was the one where the smoke was blowing from when the engine was turning over..?

 

[kshansen]

You pulled a bit more than the "injectors"! Those big things are the pre-combustion chambers I"m guessing you got a flood of coolant when you pulled that first one! You really need to get any coolant that went down in the cylinder out before you reinstall the chambers. Otherwise you are going to be starting a new thread asking why the engine locked up when you tried to start it. Or worse you will be asking why those inside engine parts are now outside the engine!

The actual "nozzle" is the little part between the red lines in the following picture:


Do you have the proper tool to reinstall the chambers and torque them to spec.? Also do you have the procedure on installing them so the glow plugs are positioned correctly? You did find the washers that were around the threaded part of the chamber, right? Sometimes they stick to the chamber and some times they are stuck on the threaded end of the chamber. In the picture with the three chamber it looks like the two end ones have the washer and the other one does not. Actually Cat calls them "Gaskets".

And yes as Nige says go to that link and that is how clean the hole in the head needs to be as well as the chambers and nozzles. When you unscrew the nozzles from the adapters the fuel line connect to make sure no crap get inside them, there is a fine screen make sure it does not have any dirt or crap on it.

I don't know about these days but back in the day when these pre-chamber engines were the latest and greatest the dealers had a simple test stand they could put the nozzles in to do a quick test to see if they were working proper, might be worth asking. They would usually not charge for the test back then as they would find one or two that needed replacing.

 

[Themaskman72]

I didn't get any signs of coolant anywhere when I pulled them out, actually it looks as dry and rusty down in there just like the radiator when I first looked in it before I added coolant. These things look so nasty and corroded that I would guess this is the problem with my no start. I'm gonna clean them all and the ports in the head like the pic. I do not have the tool to reinstall the chambers. Do you think it would be a good idea to buy new chambers? I don't know the procedure yet to make sure glow plugs are in correct location but I do have pics for that reason so I know where they are supposed to end up.

 

[oarwhat]

First off there's no coolant in the head. Was the radiator full? Second and I don't want to be mean but I think your in way over your head. First you need to get a manual and a parts book read it before diving in. That way you have some idea whats going on.

 

[Vetech63]

LOL this is turning out to be a mess! No coolant in the head, now the precups are out. Can this get any worse? I hope at least you kept the precup spacers with the proper cup, and know which hole they were pulled from. You may be over your head at this point.

 

[Themaskman72]

I have the "pre cup" spacers because they are rusted to the pre cups. I don't understand why you think I am way over my head. I own a construction company but I have always did my own mechanic work, that includes my diesel and gas trucks. This caterpillar engine is unchartered territory for me hence the reason I joined this forum and was seeking help from the great people here who know this engine or have experienced the same problems I am having. Over my head? It really doesn't seem hard to buy a special little tool to put the precombustion chambers back in so that the glow plugs are In the right spot and if not to change the spacer on the bottom with a different one that's in my kit. I really appreciate all the awesome help that I have received this far. Btw I did number each pre cup when I pulled it but that's really erelvant because I think I'm just gonna buy all New ones since they're only about 100 bucks and the tips are only about 100 bucks so I feel it will be safer with New equipment instead of using this abused stuff.

 

[Themaskman72]

Also, I added 4 gallons of coolant to the radiator when I first started this project.

 

[Nige]

Far be it from me to cast apersions, but it appears that you are in over your head .......... check out the illustration below. See the 2 red lines pointing to the "cavity" that surrounds the precombustion chamber. Guess what that cavity is supposed to be filled with..? If you said coolant you win a cookie, and you win a 2nd cookie if you come to the conclusion that the coolant is going to run from the cavity into the cylinders if you don't at least partially drain the cooling system before removing the PC chambers. If there was no coolant in that area when you pulled the chambers then the cooling system was not full and you were VERY lucky indeed .........



If you're prepared to spend a few hundred $ on parts why not part with $165 and buy a Service Manual to help you with stuff like this. You'll be glad you did in the long run. http://www.ebay.com/itm/3-Caterpill...153a9df&pid=100623&rk=5&rkt=6&sd=152001393235

 

[Themaskman72]

Ok I understand that there was supposed to be coolant around the pre cups, when I got the machine it was bone dry, yes I did get lucky that it was dry when I pulled the precups, that being said I understand that a service manual would be very helpful but you have to understand that I'm working under the pretext that this machine was running fine when parked. I didn't have any idea I would be disassembling as much as I have. I thought this forum was for people like me "uneducated in this area" to get assistance from people who know not get mocked. I build custom homes, can you do it? Yes you can but if you had a friend like me to help you along the way with things you don't know well that will make it a lot smoother and save you lots of money and time from getting schooled on it. It wouldn't be nice for me to mock you and tell you that you need to go to school on building houses when you ask me a question that is simple to me,but complex to you like how to design and cut step treads for a specific area. I'm here asking for assistance on this machine and so far the advice has been great and I appreciate it...but please don't mock me and enjoy the fact that you get to spread your knowledge and educate someone who appreciates what you have to offer. Bottom line is I'm gonna get this machine running and I don't care what I have to do or what mistakes I learn from along the way but I'm not going to pay anyone to do it for me.

 

[kshansen]

I agree with Nige, you are actually lucky this engine failed to start! If there was no water/coolant seen inside the head when you removed the chambers and it had started I'd say you would have been guaranteed at the least of having a cracked head. Actually if those chamber unscrewed while you tried to loosen the nut under the fuel line that holds the nozzle adapter in the chamber I would be worried that the head was already cracked! You really need to find out why there was no water in there before going any further!

I would suggest cleaning down inside the head real good and look for cracks, most likely going from the threaded hole towards the exhaust valve. If there are no cracks then once I found out why there was no water in the head I would just clean up those chambers and look them over real good if only a little light rust on the outside I would just reuse them at least for now. You do need to get the tool to reinstall them and don't assume that if you use the same thickness spacer/gasket they will end up in the right place. Either get the book, the best money you could spend right now, or private message me and I could send you the procedure.

If those nozzles are $100.00 each these days I would be asking the dealer to test them before spending the money but it's your money spend it as you like. Heck I knew some of the guys at the dealer back in the day would test new nozzles before installing them in an engine!

Edit: I don't read any of the remarks above as trying to "MOCK" you just a few of us who have been around these machines and engines for many years and know what works and what doesn't. I built the hose I live in and I did ask and get lots of help from "oldtimers" friends and relatives and never felt they were mocking me just because they told me something I was thinking of doing was wrong or unsafe.

One more point is that if this machine only sat for one year and ran great when parked why was the cooling system dry? Does not sound right. I find it hard to believe someone would drain the system just because it was going to be parked for a time. Or was this original operator running it with straight water in the cooling system and he was worried about it freezing. If that is the case I would be worried about several other problems that may be waiting to eat up your money.

 

[Nige]

......but please don't mock me and enjoy the fact that you get to spread your knowledge and educate someone who appreciates what you have to offer. Bottom line is I'm gonna get this machine running and I don't care what I have to do or what mistakes I learn from along the way but I'm not going to pay anyone to do it for me.

Who was mocking you..? If that's what you think then you either must have a really thin skin or don't understand my English sense of humour. I agree if you have the skills (but maybe not the detailed knowledge) then why should you pay someone to do what you can do yourself..?

What a number of people here have tried to do is help you in what, on the face of it, should have been a relatively simple process to get a non-running engine up and running - especially something as simple as a 3304PC. However you've failed to help yourself by going in there whirling spanners without the knowledge of the consequences could be. For example if you had suggested removing the PC chambers here before you actually went ahead and did it then someone would have said "Whoa, hold up a minute. You need to do a, b, c, first".

Now you have got to where you are as Ken said you need to figure out where the coolant went if the radiator was full at one time. Any sign of an external leak..? If no then you are looking internal and it'll either be a cracked cylinder head or something lower down. I agree with Ken that there's probably nothing wrong with those PC chambers that a good clean wouldn't cure. They will need new seals and obviously the correct spacers at the bottom to make sure the orientation of the chambers comes out correctly once they are tight. When they are back in place I would vote for filling up the cooling system with water and figure out some way of testing it to ensure that it is actually holding pressure. That would be the obvious next step.

 

[Themaskman72]

First let me apologize for saying I felt like you were mocking me. I have gotten a new spacer kit for the pre cups after I researched the process of reinstalling them and what they need to be torque and where the glow plug hole needs to be located. I understand that part. I a
Have also been very curious why it didn't have any coolant. There are no obvious leaks externally, there is no coolant in the oil, I am going to clean it real good today and reinstall The nozzles and chambers and see if I can't get enough pressure to get coolant through the system. If it has a thermostat I'm going to also change that as I think with all the rust in the system it is prob froze up. I will update later and thanks for your assistance.

 

[AllDodge]

Just for giggles have a look inside under the valve cover breather cap and the rockers. Se if there is any rust

 

[Themaskman72]

I already did that and I don't see any rust, just oil.

 

[Nige]

I thought afterwards about the loose PC chamber. Is that where the smoke was coming from or was it one of the other cylinders..? If it was the loose one then maybe, just maybe, it was blowing compression past the thread. If it was one of the others where the smoke was blowing then the first conclusion is a cracked cylinder head.

It's starting to look like this is a "make haste slowly" type of project that's going to need to advance one step at a time, eliminating all the possibilities at any given stage before moving forward.

 

[Themaskman72]

Yes it was the loose pc where the smoke was blowing through, I am gonna take your advice and use the same pc's. I'm gonna attach a pic of them cleaned up and I don't see any cracks.

 

[Nige]

Is there anywhere near you that does sand blasting or (better still) bead blasting..? That would be the best way to clean them without being too aggressive. You will also need a thread tap to clean the threads in the cylinder head, not only where the loose chamber was but all of them. That way you can be sure the torque you are applying is tightening the chamber and not fighting against corroded/carboned threads.

Before reinstalling the chambers if I was you I'd poke something down each of the holes until it touched the top of the piston (turn the engine over to get the pistons closer to TDC if it helps) and see if it came out wet. If whatever you poke down comes out wet you then have the challenge of sucking out whatever is in there before reinstalling the chambers. A borescope would be an ideal tool if you can beg, borrow, or steal one.

When ksh was talking about looking for cracks he meant (or at least I think he meant) in the cylinder head itself from the threaded hole where the chamber screws in towards one or other of the valves. Go back a couple of pages to that link I posted and check out Post #43. The bottom photo is what you need to be aiming for, only when the seat is really clean will you be able to see if there are any cracks in the head. Do this for all 4 holes, not just the one where the chamber was loose....

 

[Themaskman72]

Yes I was going to clean the head up really good like the photo link you posted and also look for cracks around the holes in the head. I do know someone who has a bore scope that I can use to make sure the cylinder aren't wet, good idea.

 

[kshansen]

When ksh was talking about looking for cracks he meant (or at least I think he meant) in the cylinder head itself from the threaded hole where the chamber screws in towards one or other of the valves. Go back a couple of pages to that link I posted and check out Post #43. The bottom photo is what you need to be aiming for, only when the seat is really clean will you be able to see if there are any cracks in the head. Do this for all 4 holes, not just the one where the chamber was loose....

Nige, yes sorry if I was not 100% clear on that, cracks running radially out from the center of the threaded hole. Just about every engine I came across with loose pre-chambers had cracks in that area. Problem is that seeing them with head on may be difficult.

Another question, how bad were the o`rings around the top of the chambers? I seem to recall that Cat used white o`rings in that area that would turn to mush if an engine was overheated. But even is those o`rings were damaged there still should have been some coolant inside the head.

How about something else to check? Open the drain valve on oil pan and see if there is any water or coolant sitting in the bottom of the pan. If this engine does not have a valve but has just a drain plug just loosen it enough to let it drip. Sitting parked for a year in a probably humid climate I would not be surprised to see a little water. But if it comes out green like antifreeze that's another story.

The lack of any coolant has me worried there is much more to this story we have not seen at this time. The nasty condition of the chambers and inside of the head does not make me feel confident about the long term life of this engine. Of course like I've been told more than once all it takes is time and money to fix just about any problem. All depends on how much of each one wants to spend.