need help, hard start, B6000. (video inside)

[jay87t]

Hi guys, I recently re ringed my B6000 due to low compression figuring it would fix my hard starts. I re ringed it and now my compression goes to about 400psi cranking it a few times. But its still very hard to start, takes a lot of turning over to get going, lots of white smoke on start up and I notice white smoke when running or giving it gas whats odd thing is when its all warmed up, it will start right up. Any Ideas where I should look next? Tractor does run strong.

https://www.dropbox.com/s/2py3chrvzbf2fix/20141228_143814.mp4?dl=0

 

[Apogee]

Hi Jay,

Check your glow plugs and the resistor coil on the dash (the glow plug indicator). It sounds to me like they're not working. Use a voltmeter and with the glow plugs heating, check to see if there is voltage present at the tips of them. If there is, then you need to remove the wire that jumps between them and measure the resistance of each from the block to the tip. I'm guessing you will find one or more that are open. The good news is they are cheap to replace and available from most auto parts. I'd just put new ones in if it were me... I'd also replace dash indicator as they go bad over time and this way you'd know everything was getting nice and hot like it should be.

Also, did you have your injectors rebuilt? If it is a high-hour engine, you might consider it. If the spray patterns aren't correct, they will either leak or piss a stream of fuel into the cylinder and either or those situations will also cause hard starting. It will also cause smoking similar to what you're seeing.

Don't use ether to start it. Kubotas don't like that and you will likely crack a piston.

Keep us updated on what you find.

Good luck,

Steve

 

[jay87t]

Hi Apogee, thanks for the reply I do have 10v`s at the glow plugs, I replaced them not more than a year ago. Im thinking its a injector problem. I may have to pull them and have them tested at a diesel shop. What exactly do they rebuild on the injector? the nozzel cap? a new Injector assy at kubota is 400.00

 

[CaveCreekRay]

Wolfman or one of the techs would know far better than I on how diesel injectors fare but...

My '99 4Runner lost an injector this summer. I did a day of research on the 'Net regarding "buy new" or "buy rebuilt."

In my case, buying re-built saved you about 35-40% but, the failure rate of rebuilt injectors is way higher than the failure rate of new injectors. I opted to swap all 6 out with new ones, rather than tear out the whole intake manifold and then have to do it again next summer when another one failed.

Not sure how many and how easy yours are to get to but, just thought I'd toss in my $.02. Once you get the problem resolved, may I suggest Stanadyne Performance Injector lubricant. Good both for the injectors and the fuel pump having to eat this low-sulfur crap.

Good luck and keep us tuned. I bet this thing starts and runs like new when you get this injector issue resolved.

Remember: Its all for a good cause -a healthier tractor!

Ray

 

[ShaunRH]

Were those backfires I heard in that video? Diesels should never backfire in normal operation. If they do it's usually a sign of a valve train issue. That might also explain your smoking issue. If you just replaced the rings, it looks like you may need a head/valve job as well.

I'd look up a good shop in the area and have them rebuild the valves and plane the head. Also check your cam for wear.

 

[jay87t]

never thought about that, it does not sound like its backfireing. What still throws me off is when the engine is warm/hot, it fires right up. now im not sure what route to take first. have the head machined or have the injectors checked out.

 

[North Idaho Wolfman]

I would say bad injectors, get them tested and if bad rebuilding them might not be an option, go here for replacements.
P/N 15231-53000 $124.42
http://www.colemanequip.com/parts/KubotaParts/15231-53000/

I would double check the valves but you said you got 400 PSI, so valves don't sound like your issue.
Your problem could also be in the injection pump or the cam and timing of the cam. How far did you take it apart when you re ringed it?

 

[jay87t]

I think it may be the injectors, I removed them today, and found that the part that sits in the block is soaked in fuel, not sure if thats normal or not. Going to take them to a diesel shop to have them checked this week.

 

[ShaunRH]

NIWolfman is probably right, but the problem with the valves may not be their ability to hold compression but sloppy guides and/or wear on the cam which might be changing their timing slightly/intermittently. A compression test won't necessarily find that. I am betting he just pulled the pan and pistons so the timing should not have been changed, at least my comments are running on that assumption. If the cam or gear train was changed, all bets are off.

If you can pull the valve cover and get to where a valve is with clearance and wiggle it, you'll know if your guides are shot. If they wiggle side to side, you likely need new guides, which is a fairly cheap fix you can do on most motors. It would fix oil burning issues and sloppy/sticky valve issues that might cause a backfire sounding condition.

None of that would fix a worn cam, but you can replace guides its usually pretty easy, if the backfire-like sounds continue, it might be the cam. Since you are already going to test the injectors, that would pretty much isolate it down to the cam.

Now, if you have some money to spare, having a head/valve job done is a good addition to new rings. It completes the 'top end' rebuild job.

Injector test is probably the best start though.

 

[retiredlawnboy]

To me it sounds as if the injector pump is not supplying all injectors with adequate fuel pressure. I have a 4cyl V3300 that has injector pump issues in the front bank and I am experiencing the same problems as you, white and or black smoke out of the exhaust. Two cyl are being supplied adequately and are enough to allow the tractor to run but have no power or hp with the other two not being supplied enough pressure.

You should be able to crack the supply lines at the injectors or pump and narrow it down to which one(s) and again it sounds like one and could also be another getting there as the back fire seemed to appear when you were creating an irregular flow of fuel. Try to take note of the ammount of fuel seeping from the cracked lines or you will also crack one and the tractor will want to stall, running on yet one less cyl.
Racing the pump could have allowed additional fuel to enter the chamber of the poor cyl and the rpms running enough to create pressure but was late in firing as the rpms slowed again causing the 'backfire'. Dont run the engine too much longer as the cyl that is not building up enough pressure but getting fuel will wash the oil lubrication from the walls and ruin your new ring job.

If it is the pump (most likely due to age of the tractor despite any hours used), tractorhouse.com has a list of locations with dismantled tractors you could pick up a used pump reasonably. I also saw another youtube video (cant find it now) where the owner re lubricated his pump as it had gotten dry and the plungers and springs in the pump were seizing up due to a light oxidation over time due to the age of his tractor. That didn't cost him a thing, just the time.

Good luck and let us know of your findings.

 

[jay87t]

took my injectors in today to the kubota dealer, he tested both of them and called me with the results. He said that one wont hold pressure past 300psi, and the 2nd one goes up to 1900psi but it loses pressure. I asked if I can just replace the one thats 300psi, he said its not a good Idea and both should be replaced. they are 140.00 each... he said he would absorb the bench test fee of 40.00. Guess I need to order them seeing how I will probly keep this tractor for the rest of my life. Hope this fixes my issue, Will keep you all updated, they are going to be in next week because of all the shipping delays due to new years.

 

[North Idaho Wolfman]

I'm betting you will see a night and day difference in the running of your tractor.