Perkins Diesel injection pump timing help???

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2000ssm6

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I have a 98 Kobleco TLX760 backhoe with a Perkins 1004-4T turbo diesel engine. It has close to 3000 hours and I have had it for the last 400. It has always idled rough like a car engine does when a cylinder is missing. It gets better as the engine warms up but still not smooth. Off idle it runs great and has tons of power. I will be changing the fuel filter and cleaning the water seperator(or replacing) this weekend. I know the air filter and exhaust are not plugged. I aslo use the Lucas diesel additive in every fill up to cut down on water and other contaiments. I have a service manual for it but it says to "see dealer" for the timing part. I have a good local Deere dealer but just about everyone has never heard of my tractor. It's similar to the Terex TX760 and Fermec 760 but I have to get parts, that are very expensive, from a few states away.

Anyone know how to do this or can point me in the right direction? Ask my Deere dealer? It may not even be out of time but I would like to check.

thanks!!
 
Haven't worked on the particular engine your referring to but most diesels are pretty much the same. It all depends on if its a rotary inj pump or inline. common rail or electronic. Most electronic and common rail types are timed by computer and cannot be adjusted. Rotary mechanical pumps usually have a set of slotted holes you turn the pump to adjust and the inlines usually have to seperate the tapered shaft and move it via a dial indicator in a delivery valve hole. Any of these procedures are best left to a professional as if your guessing your probably making it worse.
As far as your problem goes it sounds more like a bad injector than pump timing. If the timing is off on a diesel they usually start really hard lack power and consume alot of fuel. Hope that helps. BTW there is sometimes a line on the pumps and one on the block that you line up for a starting point and the inline pumps sometimes have a plastic alignment pin you rotate the pump and push the pin in and line it up on NO 1 TDC Comp for starters.

Mark
 
Haven't worked on the particular engine your referring to but most diesels are pretty much the same. It all depends on if its a rotary inj pump or inline. common rail or electronic. Most electronic and common rail types are timed by computer and cannot be adjusted. Rotary mechanical pumps usually have a set of slotted holes you turn the pump to adjust and the inlines usually have to seperate the tapered shaft and move it via a dial indicator in a delivery valve hole. Any of these procedures are best left to a professional as if your guessing your probably making it worse.
As far as your problem goes it sounds more like a bad injector than pump timing. If the timing is off on a diesel they usually start really hard lack power and consume alot of fuel. Hope that helps. BTW there is sometimes a line on the pumps and one on the block that you line up for a starting point and the inline pumps sometimes have a plastic alignment pin you rotate the pump and push the pin in and line it up on NO 1 TDC Comp for starters.

Mark
Thanks for the help. I will look at the pump some more on Saturday and try to figure out what type it is. I may end up calling the Deere dealer and see if they will touch it. If I'm going to check the injectors, I might as well send off the whole pump for a rebuild.:cry: :cry: :cry:

Will a bad injector cause a rough idle but run fine off idle?
 
Not typically. I'd pull the injectors and have them tested. No need spending money fixing stuff that aint broke. JMHO. Could be missing from a small air leak in the lines make sure nothings leaking and all lines are tight but more than likely its just a plugged injector or a leaking one. Typically just a bad spray pattern causing that from carbon buildup on the injector tip.
 
Will a bad injector cause a rough idle but run fine off idle?

I have had perkins engine with the symtoms you describe and after testing everything on the fuel system we were stumped for an answer so we had the timing case off and found the cause, there is an idler gear in the timing gear train which has a bronzed bush in it with an oil hole drilled through it to allow oil to lube the bush, the bush had been fitted incorrectly presumably during assembly and the hole was misaligned allowing it to block the oilway, this resulted in the bush wearing out and allowing the gear to drop during idle as it was not spinning so fast and affect the timing making the engine run rough during idle.
when the engine was revved hard the bush would centralise itself and correct the timing so the engine would sound and run ok at fast idle,this may not be your trouble but if you run out of ideas it may be worth a look, also drain the oil and see if there are bronze filings in it
 
I looked at the hoe again today. I found some dirt build up around the injectors, the lines that go from each injector to the other were loose. I tighten them and fired her up but didn't help. Must have air in the system. That took all my daylight after work to do so I'll jump back on it Saturday.

Transporter: That sounds like some good info and I believe during the last oil change I did see bronze colored metal flakes. That looks like a pita to take the timing cover off while the engine is still in the hoe.:cry: The injectors are much easier to get to, I might send them off first.:cry:

If it ain't one thing, it's another.:cry: :dizzy: :cry: :dizzy:
 
Identify Pump

Been a long time since I worked on a Perkins engine but I recall them using either a Roosa - Master or a Lucas fuel system . There should be a plate on the pump showing manufacturer , timing specs , idle speeds (low and high) . Get that info and I can be more help . Hard to say what your trouble is with no background info . You can idle any diesel with a high pressure pump and alternately crack the injector lines and listen for the "miss" .(DD's use unit injectors and they are shorted out by removing valve cover and depressing spring cage with large scewdriver . If you crack a line and hear no miss then that injector is not likely firing at idle . Always start with the most simple things because it usually is . Check fuel condition(water) . Bleed air from water seperator , bleed air from pump and filter(s) , bleed all HP fuel delivery lines . Unless you are confident in doing these things you should seek out some experienced help . Get back to me with more info .
 
It's been f-ing raining since Friday here, finally got some sun out today. I will get up pump pics tonight, stay tuned.
 
Just my $0.02 cents worth.

You have a leaky/hi-flowing injector in one of the cylinders.

It's a plumbing pain, but its possible to test them (or get a close idea) by allowing them to spray/(fire) out of the engine. The worst one is usually real apparent, comparing to the others.

You can swap injectors for rebuilt ones (or send yours for rebuild) for pennies on the dollar compared to rebuilding the pump.

Edit: If it were mine, and not sure when they been re-caled last, try swapping the injectors first.
 
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I got to degrease the injector area and snap a few pics but that is it.

The pump is a Lucas CAV, Type 688. It had some more #'s but my mirror is at work.

New ?, where can I send the injectors and where can I get the o-rings and such to put them back in. The Perkins/Kobleco dealer?

See pics below....
 
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Arrrrggggg, freaking pics....try again.......%$#@&*&^%......

Pump#1
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Pump#2
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Shotty injector pic
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My approach .

With the limited info I have I would get the engine idling and one at a time crack each injector B nut at the injector. Every time you crack(opened slightly) a line you listen for a noticeable "miss" in the engine . This will also show a drop in rpm . Re -tighten each line and move to the next . Every line cracked should create a "miss" in the idle speed . If one line is cracked and there is no noticeable "miss" then that injector is faulty . I'm leaning towards the fuel lift pump though because you describe good power at high rpm . You also suggest the injection pump is new ? A weak lift pump will not deliver enough fuel pressure nor create enough flow at low rpm but smartens up once you really get it turning . The more I think about this the more possibilities there are . Is the engine smoking? Black ? White? The first things to check are : fuel quality , tank vented , pulling air into system anywhere on suction side of fuel system . Also look for any damaged , kinked fuel delivery and return lines . Water seperators on the suction side of pump are notorious for allowing air into system . Good luck with this and let us know how you make out . If you can offer any more detail throw it out here .
 
With the limited info I have I would get the engine idling and one at a time crack each injector B nut at the injector. Every time you crack(opened slightly) a line you listen for a noticeable "miss" in the engine . This will also show a drop in rpm . Re -tighten each line and move to the next . Every line cracked should create a "miss" in the idle speed . If one line is cracked and there is no noticeable "miss" then that injector is faulty . I'm leaning towards the fuel lift pump though because you describe good power at high rpm . You also suggest the injection pump is new ? A weak lift pump will not deliver enough fuel pressure nor create enough flow at low rpm but smartens up once you really get it turning . The more I think about this the more possibilities there are . Is the engine smoking? Black ? White? The first things to check are : fuel quality , tank vented , pulling air into system anywhere on suction side of fuel system . Also look for any damaged , kinked fuel delivery and return lines . Water seperators on the suction side of pump are notorious for allowing air into system . Good luck with this and let us know how you make out . If you can offer any more detail throw it out here .
I will agree ,Check for a faulty injector this way.
One other note though. We have a generator at work with an engine that I think is identical. It is a perkins 4 cylinder and looks to be the same as yours.
It has less than a hundred hours on it and when it fires up it is designed to go right to full rpms to run the generator. Under no load it runs like crap. White smoke and runs rough. Put a load on it and it runs perfect. We called a perkins dealer about warrenty when we started it up from new and it did this and they said there was nothing wrong and to just run it. We didn't put a load on it at first cause it ran so crappy.
It might just be some odd thing with this series engines.:monkey:
 
replacing my fuel pump and need help finding timing marks for my Perkins Diesel 243

Can anyone assist me with timing marks on my Massey Ferguson? thank You:msp_unsure:
 

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