Hi all, I’ve got a 428C backhoe with a retro-fitted 3054 engine Serial No. 7BJ46984 in it. Originally had a NA engine in it which broke a rod, and I picked this up on the cheap so stuck it in. Its got a couple of issues basically: - I’ve changed the turbo on this engine 3 times, and they keep failing within less than 100 hours of work. The last one lasted about 2 hours. - I’ve got oil spurting out of the dipstick at idle. Engine oil pressure is about 65psi at low idle. Now I’ve got a new genuine Perkins turbo, but I’m afraid to fit it until I know what’s causing the failures. There’s no white smoke, engine is a half-kick start and no excessive fuel smoke either. Any help would be highly appreciated. Thanks!
That oil pressure seems extremely hi to me.!!! Check to see if it’s diluted and/or over filled.. u might have fuel in the oil.?? Have u taken a turbo apart to look at the failure marks.?? If the shaft is gaulded/metal transfer, it means lack of lube.. If the shaft is blue, same thing. U can start the engine w/o the turbo and watch the oil flow.. You have to rig up a hose to put the oil back into the return.. Another thing, I’ve seen where the return pipe gets smashed/pinched so there’s little to no return oil.. Good luck
So I’ve drained the oil and refilled to capacity (7L) and checked, but it’s still behaving the same. The turbo failure is consistently at the shaft, which would point to lack of lubrication, but I’m getting plenty of oil at the turbo oil inlet. The return pipe is also clear, but it’s spurting oil up same as the dipstick. At the moment I’ve started the engine without the turbo on, and attached a mechanical oil pressure gauge at the turbo oil pressure port. That’s where I’m getting the reading from. Ran flushing oil through the machine as well, and cleaned out the oil pump pickup sieve and relief valve as well. The relief valve piston seemed to have a fair bit of wear on it, but didn’t seem sticky.
Also no diesel in the oil from what I could tell.
And the oil pressure goes up to about 90psi at high idle.
Does the relief valve have an adjustment on it.?? What about different springs for different pressures.?? I’m just spit balling here.. idk how it works.. Ur gonna hafta wait till someone else chimes in..
Nope no adjustment on it, just a piston and a spring held in place with a flat washer and circlip. No shims to remove either. I’m not sure about different springs tbh, might be the case maybe?
Have you checked the crankcase vent to make sure it isn't restricted or plugged?
Sounds like contamination failure. You do change the oil and filter each time you replace a turbo?
Has the fresh air intake and filter been cleaned?
So the vent on the top cover is free. Is there any other vent on the block anywhere I should be looking for?
Yes been changing the oil and filter each time.
Before the last turbo I installed, I did a whole new air filter housing with a much higher flow air filter in it, just to preclude any possibility of intake restrictions
What range should the engine oil pressure be at? And if it’s too high, could this be a factor causing the sump to pressurise and possibly restrict oil flow in the turbo oil return line? Or could it just be too high and pushing past the seals in the turbo, into the impeller, and thus cause the turbo failure?
From a Caterpillar publication for a 3054. High Oil Pressure High oil pressure can be caused by the following conditions. The spring for the oil pressure relief valve is installed incorrectly. The plunger for the oil pressure relief valve becomes jammed in the closed position. Excessive sludge exists in the oil which makes the viscosity of the oil too high.
Somehow I doubt he has a valve spring tester.
Brilliant! Thank you for that, I’ve been looking all over for this info.
So according to this, relief valve should open between 60-68psi, but I’m getting close to 90 at high idle. So that’s definitely an issue
I’ll try changing out the relief valve for another one tomorrow and revert. Flushed the engine out today and put fresh oil on as well.
That would be a correct assumption unfortunately. I will measure the free length though.
Oil sample would not be a bad idea and maybe cut open one of the old oil filters just to know what’s floating around in there.
Are you prelubing the turbo? Its a pain to get oil into that tiny supply hole in that turbo. I always prelube a turbo upside down through the drain opening first the install and prelube through the top.
I pre-lube the turbo with a old oil squirt can then install, then I leave intake boot off and using a long phillips screw driver I insert it into intake compressor wheel holding it/locking it up while I have someone start the engine. I hold it for a few seconds or until I'm signaled by the person starting that the oil gauge is at full psi at idle, then quickly remove lockup tool/screwdriver. Been doing that for 45 plus years, never lost a turbo from lack of start up oil.
Yep I’ve been pre-lubing with a squirt can before install.
I’ll try it this way once I install this one.
Well at least you know your oil pump is good. The relief is your issue. If you are still pushing oil out of the dipstick after you may have pressure in your crankcase. This could prevent the oil from returning from the turbo. This effectively means you turbo is not being lubricated. Once you get the oil pressure issue worked out check crankcase pressure. Rig up a vacuum gauge to the dipstick tube and measure the crankcase pressure. It should be a slight vacuum. If you read pressure there you have an issue with the breather system. Pressure in the crankcase will cause seals and gaskets to leak oil. If you find sludged oil to be the issue it would reason that the breather system is sludged up too. There are all kinds of methods to try and remove sludge. Marvel mystery oil, kerosene, rissole and many others. Unless it is severe just switching to synthetic and changing it often will eventually clear out the sludge.
So I’ve changed the relief valve. Should be starting the machine again soon and measuring oil pressure again. Yes that’s what my initial concern was with pressure in the sump basically pushing back against the turbo drain oil and not lubricating it as it should. I’ll revert back once I’ve measured the oil pressure with my brand new second hand relief valve.
Oil blowing out dipstick worries me. Have you done a compression test?Might be low in a cylinder, either pressurising drain from blowby and restricting flow or possibly causing a pulsation in exhaust killing the turbo. High oil pressure could also be a symptom of a spun bearing.
The crankcase vent may also need to be replaced.
Only two things going cause oil to push out of dip stick tube, {plugged crankcase vent, or crankcase pressure and or a possible third-it's way over full on oil. The turbo feed is under pressure, way more oil pressure than any crankcase pressure could possibly block oil drain tube at turbo. High oil psi is not causing oil to come out dip-stick tube. * So two issues. High oil psi and crankcase pressure--Betting it's got a bad cylinder, JMO.
Did a lot of Perkins warranty work and if I had a dollar for every 1004/6 Phaser (3054/6 Cat) engine we had to replace a liner in with those symptoms……The ring lands on the pistons were thin and weak and the liners were paper thin. They definitely did not like starting fluid. A proper leak down test and pieces of liner in the oil pan were usually good indicators. It always surprised me how well they ran in that condition.
So oil level is okay, and crankcase vent (in top cover) is okay. So do you reckon I just pull the head and check the rings and liners?
If I do need to replace the liners, are they removable or will I have to strip the block and take it to a machine shop?
Haven’t done a compression test yet, but it would probably make sense to do this before taking anything apart I suppose. Any idea what sort of pressures I should be looking for?
Compression test Spec is 355-427 psi@250 RPM. Anything below 300 would be a concern or a 50 psi difference between cylinders. as long as the parent bore in the block is not damaged the liner can be changed in frame Perkins offered two different liners finished and unfinished. You Do you want to make sure and order the correct finished liner unfinished liner will have to be machine after installed. they are a pressfit liner and need to be carefully measured after install with a boar gauge. But do the testing first. If you can pull the oil pan I’d do that before I’d pull the head, but I don’t know what kind of clearance that machine has to get the pan off? Happy hunting
Wasn’t able to start the machine today because of electrical issues, but it’s all been sorted now so should be testing pressures tomorrow. Sump is very easy to pull, nothing in the way, so it was quite easy to change the relief valve as well. What would I specifically be looking for at the bottom end? Thanks
What happens when you remove the oil filler cap wile running
Do the testing first while you still have oil in the sump to crank the engine over. Don’t forget to disconnect the fuel solenoid while cranking so it doesn’t pump fuel everywhere. You’re going to have to come up with an adapter to replace the injector to hook up your gauge up to.(You will need a set up for diesel engines a standard automotive compression tester won’t do it). You can easily make an adapter out of an old injector. The cold start on that engine is in the intake manifold, so there’s no glow plugs to be able to tap into and do the test. Forgot you already had the pan off. There was no metal in there? Removing the pan would gain you access to look at the liners on the bottom end for any scoring or damage or excessive wear it is better to check them with the head off but if it does have one hole that failed compression you’re probably gonna have to pull the head the pan and the piston anyway. if you do have one cylinder that fails compression double check and make sure you do have valve clearance at TDC Intake.008 exhaust.018.
Not a significant amount of puffing at the top end.
So luckily I had a fitting for the injector, so just done the compression test. Results are: - Cyl 1 - 200psi - Cyl 2 - 255psi - Cyl 3 - 265psi - Cyl 4 - 215psi No metal in the sump that I could see, although the oil initially was quite thick. Rechecked valve clearance before doing the test, they were all tight, so brought them to spec.
With #’s that low, I don’t see it even starting.!! Your gauge might be off by 100 psi.??
Did the engine still push oil out of the dipstick with the cap off? Didn’t think of this earlier, but I would verify that that is the correct dipstick for your sump to be certain the level is correct. Do you have access to another gauge to verify.Was the test done with all the injectors removed during cranking? Being in it this far I would do the leak down test as well.
That thought crossed my mind but I never went back to check if the question had been asked before. Have you tried draining the engine oil out to measure the quantity then compare it with what SHOULD be in there.? The original engine oil pan should contain somewhere around 7.3 litres, not sure about your replacement engine unless you can indicate what machine model it came from.
It’s a relatively new gauge, and I haven’t had issues with it on other engines. But probably best to counter with another one just to make sure
Yes even with the cap off it’s still pushing oil out of the dipstick and turbo return line. I’ll try and look for another gauge to counter confirm. All injectors were removed, and compression tested one by one. So what does the leak down test involve?
Yes so I drained the engine oil after flushing. It had slightly shy of 8 litres in it. Put exactly seven litres in after cleaning out the sump. The engine serial is 7BJ46984, and I’m not absolutely sure, but I think it came out of a 315 rubber duck.
Also, changed the relief valve, but the oil pressure is still high 60s on idling and 90psi when you rev it up.
I’m starting to think there’s a chance there could have been compression leaking out of the sides of the fitting I put in. I’ll redo the compression test tomorrow and see if the results are any different.
A little bit of soapy water would confirm that.
If it did then allegedly the oil capacity is approximately 9 litres if you are using the oil pan that came with it.
Even if it was the cylinder balance is off 65 psi with what was posted. If it does have a bad cylinder the higher the pressure the more offset it will have. If you have 7L in a 9L pan there should be no issue in that department by what I'm reading.
Make sure you have a battery charger/booster connected or at minimum fully charged batteries. If the engine is cranking slow your numbers will be low. Also make sure to watch the gauge when cranking, not only is the final pressure reading important so is how consistent the pressure build is with each cylinder. I usually do 5-6 compression strokes per cylinder. A leak down test has you put pressure in the cylinder at TDC of the compression stroke and it measures how much air leaks out. Again the raw number is important but the difference in each cylinder is as important. When doing a leakdown test make sure to remove the Schrader in the hose. If not you will only be testing your hose. If the loss is over 10% listen for where the air is coming out. Sometimes putting a rubber glove over the exhaust pipe and engine oil fill helps. If leaking the glove will inflate.
Let’s grasp some straws. What’s the possibility of a bearing, post oil pressure sender, that has turned, slipped, moved, and has partially blocked the pressure galley? That would explain higher than normal oil pressure and weak lube pressure/volume at the turbo. If the oil pump is unable to move the volume of oil as designed the oil pan would remain full and the crankshaft would be throwing oil from being flooded.
It's a good thought idea and one I kicked around--99% of the time if that were to happen it would cause a catastrophic failure, yes it could happen--case in point. A Cummins 855 can spin a cam bearing--partially blocking oil rifle and still have just barley enough to lube rockers but never enough to operate the jake. It's very rare normally causes major destruction, but it doesn't cause a high oil psi. Not saying it couldn't happen here.
Just re-done the compression test with a crush washer and Teflon tape on the fitting and soapy water to confirm. Put in a fully charged battery and boosted with another. Same results as before.
Yes using the sump that came with the engine. So then I’d suppose over-filling is not the issue.
Yes so did the compression test again this morning, same results. Ahh okay. I’ll try and rig that up then and see what results I get.
I’ve been thinking along the same lines. Since I don’t really know the history of the engine, or how often it was serviced etc, could also be sludge in oil galleries preventing proper circulation of oil and high sump level? Actually pulling the engine out of the machine atm, then I’ll be able to have a proper look at the bottom end. Is there a way to blow compressed air through the whole thing and just properly eliminate any potential blockages? I’ll also open up all the con and main bearing caps and check if any have spun/begun to spin
So just a bit of an update: Got the engine out, stripped it down. Two of the oil splashers under the liners were completely blocked up with sludge and metal particles. Blew compressed air through all other oil galleries etc, cleaned it all out. Liners had a fair bit of a ridge on them, so put new liners in, and got new piston rings. Waiting on main and con bearings now, should be putting it back together in a day or so. Will hopefully do a bench start before putting it back in, so I’ll update on all oil pressures etc. BTW, no spun bearings or anything to block off oil. Bearings have slots in them anyways instead of holes, so even if they did move, still wouldn’t cut oil flow off.