PC75UU-2 fuel pump timing

[dany]

Hi every one.
Fuel was leaking from the delivery valve hoder of my fuel pump.
I changed the 4 O-rings on the delivery valve holder of my fuel pump. I also changed the 4 copper gasket as well as the 4 springs. Now, it stopped leaking but the PC75 is smoking (black smoke) like hell. It is starting well. I torque the delivery valvle holder to the spec (32,3Nm or 23.8 foot pound)and double check with a second torque wrench. The dealer says it is probabley the timing of the pump that has too much advance. But I did not touch to the timing of the pump when I changed the parts.
The story of too much advance makes sense though.
Anyway what do you guys think of that?

If I need to recalibrate the timing I need to loosen two bolts. I have the shop manual and it is explained there. I can find one of the bolt. It is easy it is indicated on a diagram. But the other one I cannot find it. The one I am lloking for is the nut/bolt on the oblong hole of the mounting flange. I am so frustrated not to find it.:Banghead
Because of that I will need the dealer to come here at 120$/hour to do what I could do if I could find this Fu ..... nny bolt.

I intend to remove the counter weight this weekend to ease and fasten the dealer work when he comes maybe next week.

Any of you guys know wher this bolt is?

Dany

 

[John C.]

Which engine does that machine have. There should be a tag on the valve cover or on the side of the engine block.

 

[Chris5500]

Checked your air filters?

Like John said, what engine have you got and what type of pump?

 

[dany]

Thank you guys,

Sorry for not answering yesterday, I was on the road.

Air filter is ok. But to make sure, I removed it, start the engine and same thing.

The engine model is: 4d95L-1
The fuel pump is a zexel

Your feedback is appreciated

 

[John C.]

Your engine in the common Komatsu engine but I've usually seen them with Diesel Kiki fuel systems. There are three bolts that hold the pump to the engine for the Diesel Kiki systems but since you did not take the pump off as part of your prior work I can't see as to how you could have changed the timing. The third bolt is between the engine block and the fuel pump. You really can't see it, probably be lucky to even reach it with your hand. It had a twelve point head.

For timing the fuel pump to the engine there should be a chisel mark on the top outside bolt and a corresponding mark on the engine front cover. As long as those are aligned the engine should be in time. Unless something got broken that should not have changed.

The more likely problem could be the thickness of the washers you installed under the delivery valves. As I recall those are of different thickness which set the point at which the valve opens and lets the fuel flow. You might try to install the old ones back in.

Does the engine seem to have good power, is it easy to start and how many hours are on it.

 

[John C.]

I just found my engine book and now see the issue you have with the bolts.

The fuel injection pump is mounted to a cover with what looks like two studs. The cover itself is mounted to the back side of the front cover of the engine. There should be three bolts holding the cover to engine front cover.

The timing of the pump is adjusted by loosening the cover the pump is mounted to and turning it. You remove the check valve in the number one pump and put the holder back in. You rotate the engine while watching the flow from the holder. When the flow just stops check which mark you are aligned with on the balancer. My book shows a PC75 should stop at 16 degrees before top dead center. My book is old so you need to check this in your book. If you are advanced or retarded you turn the pump housing/mounting bracket and try again till you have it right. Put the check valve back in the holder and you are ready to go.

Good Luck!

 

[joispoi]

I'm not familiar with this particular motor, but if you didn't rotate the pump already, leave it set where it is.

Does the black smoke smell like unburned fuel? It's possible that when you swapped out the o-rings, some dirt got in one of the lines and is obstructing an injector nozzle. If the injector is stuck open, it will squirt raw fuel instead of spraying a fine mist. Raw fuel = black smoke.

Give everything a good cleaning before you pull the injectors.

 

[dany]

Thank you' I am working on it. Yes there is one mark ion the pump aligned with on on the engine.
The engine starts easily. It has 3400hr on it. It has power but I cannot leave it working, it is producing too much smoke in my garage.
It does not smell like unburn fuel, just black smoke.
John, I am printing your post and try to locate everything

Thanks

 

[dany]

Did not find what you said John. The counter weight is removed and I can see very clearly everything.

 

[hammerdwn20]

We have a PC75uu at work. Im not familiar with what youve done since ive never had to do it. Maybe the springs you replaced were of a different rate?
I wouldnt work that machine until you repair the smoke issue. Excessive black smoke screams high exhaust gas temperatures which could burn a hole in the piston

 

[willie59]

I have no idea what the problem is, but I can't see how it's the timing needs adjusted because you worked on the delivery valves. How does that change the timing? :beatsme

 

[dany]

Just changed 4 little o-rings, did not adjust or play with anything. Before it was running like new, now it smokes like an old charcoal boat.
The springs maybe differents, but they are the right number for this excavators. Maybe its the one before which were different and they did the timing of the pump accordingly.
I am confused and my wife is not happy at me because I am spending all my weekend trying to cure the PC without succes.
It is looking more and more like a dealer job before I scew up something.

Thank you all

 

[dany]

update

Too late! I screwed up.
As I wrote I called the Komatsu dealer. It was not the timing. They took the pump of and brought it to a pump shop. When I changed the O-rings, I asked my son to crank the engine just to see how the pump work. Call me stupid and I hate myself for it, the plunger moved out of their slot. When I put the holder back, it broke plunger 3 and 4 as well ( well, like a well done job idiot!ointhead) as the pump housing. Just to fix the pump, it cost me 1600 nice little$$. So the Komatsu guy came to install the pump. The engine would not really start. It made an effort but not enough. The pump was dismounted and taken back to the pump Guy. Doubled checked and everything was ok. So Probably because the pump was so overfueling it broke an injector. ...«Nice job..:Banghead.» A total of 3 visit from the Komatsu mecano later the engine is now working fine.
Fine will also be the bill when I receive it.
Anyway, I have learned my lesson. I I ever have to replace the pump holder O-rings, I Wil NOT NOT NOT crank the engine just to see how the pump is working.

 

[thepumpguysc]

OMG!!! 1600.00 FOR A PUMP..??
By the time I got done reading this thread, I knew what had happened..
I could have sent you a "break-down" and you could have {maybe} fixed-it yourself.
What you did was> moved the "barrel" out of its "slot"..and sheared the locating pin.
What they didnt tell you is> theres PLENTY of locating pin..
Remove the barrel{better left to the pump guys} "re-locate" the pin and off you go..
Sorry you got hosed...
Mail me next timel.

 

[MrKomatsu]

:usa:usa:drinkupdany...if it makes u feel any better i myself have blundered also in this area...very important to pay attention and try not to get side tracked...also remember to put plungers and holders in the hole they came out of...John C. has alot of info.....if you still need any help in the future..we r here 2 help...take care.

 

[thepumpguysc]

BTW> seeing you ALREADY have a NEW PUMP...
See if you can get your OLD ONE BACK...
There is NO core charge..{believe me, I know}

 

[Tracktorsboy]

help me
i have trouble, my komatsu pc 100 - 6 error 05
any one can help? What problem is this?

 

[Tracktorsboy]

help me
i have trouble, my komatsu pc 100 - 6 error 05
any one can help? What problem is this?

 

[MrKomatsu]

e05 or 05...is a service code regaurding your govenor system....possaible linkage and or motor issues..need to look for active codes to really determine....respond back to me at edkresa@gmail.com...

 

[dany]

update (ctd)

OMG!!! 1600.00 FOR A PUMP..??
By the time I got done reading this thread, I knew what had happened..
I could have sent you a "break-down" and you could have {maybe} fixed-it yourself.
What you did was> moved the "barrel" out of its "slot"..and sheared the locating pin.
What they didnt tell you is> theres PLENTY of locating pin..
Remove the barrel{better left to the pump guys} "re-locate" the pin and off you go..
Sorry you got hosed...
Mail me next timel.

I did not know what the prpblem was and this is why I called the dealer. The mecano did not know neither, but he suspected a pump problem. Then he took the pump to a pump guy who found the problem. The rest is history! If I knew what the problem was i sure could have process otherwise!

Anyway, I got my housing back although the pump guy said to me that the pump housing is not usable anymore, since fuel is leaking into the engine oil because the plunger were misaligned and somewhat «enlarge the aluminum housing. I also have the 2 defective plunger, the spring 4 new O-ring, 4 used Copper gaskets and 4 new copper gaskets. I don't have the whole new pump because they rebuilt a new one using parts that were fine.
The story was then 900$ for the housing, around 100$ for the plunger (times 2 because 2 plungers), gaskets to link the housing to the governer, other gaskets that I forget, work, taxes and here we go for 1,6k$
That you everyone for answering me.

Dany