I noticed today on my 953 that I have a small fuel leak developing in what seems the back port of the pump between the engine. After examining the lines and fuel return I've ruled out leaking from the external sources such as supply lines and return and injector lines. I read in my shop manual about the governor control shaft and somewhat suspect that that shaft may have worn through a plug at the end of the pump and may be seeping from there so I am still considering that as a possibility. My question here though is this. Is there any other seals on the back side of the pump that may have blown to cause this leak? It is deffinatly diesel fuel leaking and it seems to come from the back of the pump. the eninge is not affected in HP and seems to start and run good, So would this be a fuel resevor problem in the body of the Pump? The leak does not seem to be coming from pressure or nothing, just a seep. My shop manual does not address this issue and would like a little heads up before I open it up. thanks!:usa
In a 953 you've got a 3204 engine with a scroll type pump. As far as I remember, the only things connected to the fuel gallery on the back of the housing are dowels which locate the FIP bodies on the early models. Do you have a photo of the leak and serial number?
I'll get the Camera charged up again and see if I can get you a decent photo of the leak. I guess I'm really suspicious of the Governor control rod that runs through the pump and as it seems to me that the end of the rod has a steel "welch" style plug at the end of the pump or maybe just a seal of some sort in the fuel resevor.......i don't know......in the mean time I'll bring the shop manual in to be scanned and send you the pump schematic/drawings maybe you can make sense of it all. I guess the frustrating thing is not being ablel to see exactly where the leak is originating. I've tried mirrors and extra lights and etc. guess it's time to start taking engine housing open for a better look.:beatsme
I'm thinking that if there was a leak in the governor shaft area, it would be engine oil and not fuel.
I spent the night trying to find a decent phot in my manual to show where I see the leak coming from and where is it wet. in the photo the middle section of the fuel pump is wet directly below the center housing and alo on the end of the governor control shaft. If you look closely at the pics you can just barely see the arrows I've drawn into the manual, I'm sorry for the faint markings, I did not want to mark up the maual too much with pen and pencil just does not show well. This photo is of course a fuel path diagram but it shows the body of the pump and etc better than the little pics that are otherwise present in the manual. still working on the pics from camera, they are too large to download here as of yet.
Your diagram is showing the engine oil path. It looks like you've got engine oil leaks from all the common places. (A) An oil leak from between the oil cooler base and the governor body and (B) Probably the tacho drive shaft seal is leaking. The first one is fairly simple. You'll need to drain the coolant and remove the oil cooler, then the cooler base and replace several gaskets and O rings. The second one is also not hard to fix, but you neet to dismantle the governor to get to the tiny lip-seal. Also if the tacho drive shaft is worn, you'll need some special tools to replace it. If you're a confident mechanic, I would say give it a go, but if you're unsure I would get yourself a cat mechanic who's familliar with fuel pump repairs. It is possible to reassemble it wrong and the consequences of getting it wrong are an engine that goes to full fuel on start up and you can't shut it down. Good luck.
indeed you are right about the oil galleries in the diagram, my mistake, there where two diagrams in the book and I just used the wrong one. In the way of the leak, after purchasing some dye and adding some dye to the tank, and running it with a white cloth suspended under it the leak turned up red on the cloth. deffinatly not oil. Anyway, my brother said to give Advance diesel a call and so we'll let them take a closer look. much better to let the professionals work. If I were to tear it apart, i'd mess things up. but still open for any thoughts you may have
If you have diesel leaking in these places it would seem rather odd, for the only diesel should be in the pump housing and oil in the governor housing. I have a problem also with fuel dilution leaking somewere in the the pump housing and draining into the oil pan. Looking at the service manual and parts book I can see no seals on the inj. pump cam . Could anyone give me an idea were it's coming from. I already took the governor housing off and checked there, no leaking on that side. This is on a D4C.
Monte, You don't need to make any marks on your service manual. First thing to do is scan the page of the manual with your scanner. 2nd - print the page you just scanned. 3rd - Do all the writing and marking on that printed page you want. 4th - Scan the page you just made your notes on and post it on the forum.
I would take a look at your fuel transfer pump as the possible culprit. If you can send us some more info on your machine and possibly a photo I am sure we can help you out.
thanks tinkerer....more than one way to skin a CAT I guess. Since first posting, I've consulted with Advance diesel and the options only seem to include getting the injector pump off and sending it in.....geez....and ya would think it would fix it's self if I talked nice to it.....lol seems as though it's still "wet' behind the pump, but not getting any worse for wear. I'm hoping to be able to get a little more time out of it yet and square away for a thorough repair. I hate leakers as much as the next....but hate doing it twice too.
Monte, I was just wondering would it be possible to put a plate and gasket over the tach drive opening on the pump? I keep thinking that one of the pumps I built a few years ago had one on it to stop it from leaking until they could get me out to fix it. I am just curious because that may be something you could do to keep from having to pull the pump and send it in.
If it is the tach drive seal leaking then it can be repaired in the machine without removing the entire pump. I have replaced just the lip seal but the shaft normally need replacing because a grove gets cut in it. This can be done by carefully removing the housing. There is a cover that goes over the tach drive but it is just designed to keep out dirt.
I was asking about making a metal plate to seal it off with. I may be wrong and I am sure Lee-online can answer this but ain't the tach covers that come from cat to put on the pumps made out of plastic? I have changed the seals on the pump also, and like Lee said the shaft has almost always had a good grove worn on it. But I keep thinking there is room to drive the seal a little deeper in the bore to get the seal on to a better spot on the shaft. Or you may be able to drive the seal in not quite as far as it was and do the same thing.
I'm getting a bit confused if it is supposed to be an o ring seal or a lip seal.........I'll check on the cover idea, but to me it almost seems as though that cover that you speak of is metal. I'll be headin over to site again tommorrow, and I can take a flash light along and try to look into those ideas. I'm not apposed to just sliding the seal in a little less further or whatever. if it makes things any easier, sirs I've got crocus cloth here, and lathes to spin the shafts for polishing can you enlighten me as to wether or not that governor shaft comes out, or can a person just slip the end cover off? just trying to open up some new ideas for ya I'd hate to have to pul l the injector pump off and go through the process of re timing it.........your thoughts?
The seal we are talking about on the tach drive is a lip type seal. Also I may be wrong about your cover being plastic on your pump. But I think most of the pumps I have seen that still had one on them where plastic. On the shaft, the ones I have seen leaking have had a major grove worn in them. So I don't think polishing it will help it any. But if you do decide to replace the shaft though I can walk you through the process. Just remember if you do not feel comfortable with changing the shaft your self then I would not attempt it. It is not a job I would recommend for most people.
Smitty: mechanicaly speaking I can usually get it done, sometimes with help, sometimes just by readin the book, as you probably have guessed I've got the complete shop manual for my machine, but still sometimes the manual does not show very good detail. I'll be bringin the 53 home in a few weeks, and if I can get some "borrowed space" in my brother's shop on the farm here I can get a better look at it. I'm thinking that a good cleaning is in order and then probably remove the engine "hood" and radiator supports. i know you probably don't think this is necessary but I've got some other small details I want to take care of as well. I'm thinking of getting some plumbing hooked up for an aux hyd valve. (I don't have third valve and need a grapple fer sure) so it becomes a "while we're in here sort of thing.
I'm the guy with the D4C,same engine and pump. I also have a D3B with the same pump which has leaks in the same areas as yours, but it seems really its only one leak coming from the tach drive and running down and puddling on top of the oil cooler. I simply took an old mechanical hour meter, which has it's own o-ring, and put in the tach drive and it hasn't leaked since. But as far as my problem with fuel dilution in the engine, tranfer pump checked out ok, it must be leaking fuel past the individual inj. pumps ,or at least one of them, as I removed the whole inj. pump itself and hooked the lines back up and it's coming out of the front of the pump were the oil from the cam housing drains back into the engine. Don't know how it could have happened all of a sudden. Has anyone experienced this problem,or know were I could find a new or used complete pump. Tried Holt Cat used parts but they don't have any.