Hi guys I’ve rebuilt the engine in one of my D7H serial no 5WB 4127 3306 10Z 219119 New crank,pistons,liners,valves guides bearings the whole deal it’s back at work and running great The engine oil level is a worry When I check the oil level at the end of the day,with engine at idle it is down 4 or 5 litres,when I check in the morning before starting,it is back at the full mark When I start the engine from cold,and let it idle for a few minutes,and check again,there is only half an inch of oil on the stick,this is a real worry, I did the same procedure on one of the other 7s and it only drops 1/2 inch from the full mark I’ve checked the top of the engine for excess oil that was ok I’ve dropped the oil pan and poured oil into the filler pipe to make sure it’s not flooding the front gear housing,the crankcase breather is clear,the turbo drain is clear Any ideas guys,any help sorting this out will be really appreciated Regards Wayne
Doesn't the dipstick on one side say check with warm oil and engine running? And on the other side of the dipstick there is a "safe starting level" mark?
Hi RC yeh that’s correct and I’m aware as to how these are applied I’ve owned every model D7 over the last 42 years had plenty to do on the 3306 but this has got me scratching my head thanks for your reply
I can't say I've come across this problem before but have you thought about your scavenge pump?
Hi Cmark the pump was regearded and new pressure relief valve I’ve thought maybe large internal oil leak but has 80 psi at high idle and 20 at idle
Yes but the scavenge section is completely separate from the lube section. I don't think there is any way to test it with the engine running. AFAIK you can only check the gears are good, and that the pickup tube and seal isn't damaged.
I will check the pump and pickup tube again there’s a lot of oil hanging up somewhere in the engine at cold start could be as much as 8 litres
Wouldn't the oil run down the plate to the sump if the engine was level? Maybe park the tractor with the rear end uphill? Bob
Yes, I would imagine so as well. It's just my best guess so far given the situation.
I hope he lets us know what he finds bet it's something silly. Bob
Is there an orifice designed to limit the oil flow to the valve gear on that engine.? From the sounds of it the oil is taking too long to drain back to the oil pan. Provided the tractor is level it ought not to be necessary to scavenge oil from the back of the pan to the front, gravity should do that.
Did it do that before you worked on it? Was it an inframe overhaul? I don't know those tractors well, but I have had similar with some older stuff. Bad rear seal transfers oil into the torque converter and over fills the transmission etc. and then it could possibly drain back when setting shut off.
Very interesting post. I had a similar problem with a D342 in a D8.Like the OP,I was well aware how to check oil,but the oil seemed to disappear during the shift to the point I’d switch it off at brew time to let it settle half an hour,then check it. It would give you a heart attack checking it after a couple of hours with the engine ticking over.I knew the oil was in there after spending a few weeks being sure it wasn’t slowley transferring,but I often ended up overfilling it. As for checking it after a cold start 10 minuits into the shift,it would naturally show a low level. To be honest,I never got to the bottom of that engine and I never liked it. Some years later after around 3500 clock hours,I replaced the entire engine as the oil pressure would drop after a few hours. I should say,that many years ago during a bit of a tart up,my chap found the oil gallery had fretted at the elbow where it fired oil into the filter.It was a good find by him as my eyes never saw it. Perhaps it went again?. Anyway,I feel your pain sir,and keep us updated please. Good luck
Here's a shot in the dark. The dipstick tube should have a small tube attached that allows it to breathe. Is everything in order there? No plastic caps been left in place from the repair?
What is the odds that the head gasket was wrong or installed backwards and the drain port for the valve drain is blocked off? I've actually seen this happen on another engine. I don't remember how that engine is set up and whether the drain is through the pushrod casting holes.
Maybe have a look in the valve cover to see if the oil is pooling there.
Hi guys thanks for your reply’s Nicky especially reassuring to know I’m no alone on this trek I’ve removed the oil pan and all looks ok it’s fair got me scratching my head this one I’ve started another of the D7s and checked when cold and it’s hiding about 5 litres when cold so that’s 3 I’ve checked that all show different oil levels Yeh Nicky add oil which overfills it,it burns the overfill off in a shift,use the cold level and uses very little maybe 2or3 litres after 40 hrs We fuel up and check oil levels at end of day this tractor has always been an engine oil user. This low level on start up makes me real nervous I’ve followed up on everyone else’s suggestions thanks guys.Mark your shot of the dipstick and tube there’s no stick showing out of bottom of tube that is what I found when I removed mine On the earlier PC 3306 there’s at least 2 inches of the stick out the bottom of the tube I’m thinking maybe turbulence in the pan when cold not allowing an accurate read ? Thanks guys great site this,you guys do it proud
Funnily enough,I’m in the process of ordering a new dipstick tube for a D9 from Cat. It’s actually worn holes in it and I’ve patched it up a couple of times with bits of tubing,old hose and clips.It still leaks abit of oil,but after reading this thread the other night,I’ve decided to stop faffing about and just buy one
Have you tried removing the valve cover(s) and run the engine to check if oil is accumulating in the top end.?
Yeh Nicky I recall my PC engines showing some wear on the stick where it exits the tube my thinking now is cut 2 inches off the end of the tube at least I then can be sure of a better contact with the oil and hopefully a more accurate reading Yeh Nige I did exactly that early on,the oil capacity on top of the head is minor it flows over the side down to holes in the casting between the cam followers and into the pan When I lie under the engine with my spot light shining up into it I’m thinking there’s no way that amount of oil can hang up in there,if I spill some on the workshop floor it runs faster than I can What do you think of my above suggestion worth a try? I have 2 more D7s that I can do a cold start comparison on when I get to them
Hi vetech the head gasket will only fit as intended hi chidog rear seal was replaced I have had what you describe happen in the past but sure it’s not in this case the trans oil runs clear as in these things the black oil would show up quite easily on the trans dipstick it’s so clear it’s quite difficult to get a accurate reading have to rest the stick on the end of my nose just about
Have you ever changed oil and added what the service book called for checking the gauge? When you check the oil hot do you add oil? Bob
Has it got the right dipstick, just a thought.
Good thought about the dipstick by the above poster. Fortunately,the chap has other D7’s that he can check with on site. That said,wether it’s the right dipstick or not,the oil is still jumping about somewhat. It’s definitely worth checking though half an inch in the wrong direction on the stick could mean a gallon of oil in the wrong direction in the sump.I guess if it was well overfilled it could give false readings on that stick if it can never quite settle right. I’ve just ordered my new dipstick tube from Cat for the D9 this morning.As a precaution,when I fit it,I’ll just compare the dipsticks with the other D9 to be sure.
As a side thought,had anyone fitted a new dipstick tube on a C18? I’ve only been able to take a rough look without dropping the belly plate and it appears to be pushed into a hole on the block. My chap in the office that sent me pics is now caught Covid,so I’ll be getting no more looks at a service manual for a while. I’ll post some pics when I get around to doing it
These are best pics I can get. I’m not really qualified as to how that actually inserts into the block,but it’s feasible to consider that the OP has been into this area when rebuilding his D7 and possibly disturbed something in the orifice.I’m thinking that a piece of blue paper,rag fragment at this point? It’s a long shot,but if everything else has been done to his satisfaction,it’s worth a thought that the trouble could simply be in reading the oil level. As another poster here said,it’s worth putting the absolute exact amount of oil in that the manual states. My D8T supps 34 litres according to the manual.I allways precisely measure the amount that goes in upto 33 litres,then check things as they’ll be some residual still in there somewhere. Back in the day,I’d simply chuck four 2 gallon buckets into the D342 D8’s and they would be near enough for my taste,but I’m very strict on not overfilling the C series D9 and D8 engines.
This is the abortion of a dipstick I currently have stuffed into the D9.I’m ashamed to say that I’ve had it over a year and not done anything to sort it out as the D9 was supposed to be a short term thing.I’ve ordered the tube for it and will remove the belly plate and take a good look in there as I’d like to see what’s underneath that rubber engine moulding.There’s oil getting out of the block somewhere next to the starter.It’s not critical,but I’d like to take a peek when I fit the tube. Does anyone know what’s begind that rubber cover thing? It’s a D9T RJS series. Thanks
Yeh Rd it has the correct dipstick the engine oil capacity spec is 27 litres While the pan was off I took a series of measurements to give myself a better picture of my concerns,with 1/2 of inch oil on the stick there is still 2 1/2 oil in the pan that’s eased my nervous level ! Then I look at the shape of the pan it slopes at about 45 degree front to rear both ends hmmm, that 2 1/2 inches of oil in the pan would be less than 10 litres possibly as little as 7 litres wow that a lot of oil in transit All of these measurements improve slightly as the engine temp rises then when I shut the engine off it takes 8 hours to record full level on the stick again I will be like Nicky soon and need a new dipstick I’ll have worn my one out
Fair play You’ve given it your best shot it getting to the bottom of things.
If you do this, there will be no more checking the level at idle, the oil being splashed about will be all over the stick, unless the marks will still be in the tube? In which case, carry on.
My 3306 PC engines have 2 inches of stick out of the tube and they give an accurate oil check at idle so I have no worries there,DI and PC engines are identical in pump and sump department