nanni t4 155 burnning oil part 2

[bluejasper2]

hi again, the saga continues
we did what late starter suggested re checked oil took boat out gave it a good run out for a couple of hours, engine running fine no smoke above
2000 revs. came back into marina let engine idle for a while burnning oil again.
friend then had a word with local boat engineer(not nanni engineer)
he said could be leaky injector. but would this just put more fuel in cylinder
and cause black smoke.we have been watching the oil level closely and it has risen about 4mm , this has got us stumped. there are not many engineers in
the north east. the local ones do not seem to be interested.any thoughts will be appreciated (nearest nanni dealer down south)thanks paul.

 

[rafiki_]

If you are injecting too much fuel into the cylinders, then this could blow-by the piston rings into the sump. This is the most likely cause of a growong oil level.

 

[Cymrogwyllt]

if the injector is letting too much fuel in to the cylinder it is entirely possible that unburnt fuel finds it's way past the piston in to the sump raising the 'oil level'.

Similar to a car fitted with DPF repeatedly failing to complete refresh (not the correct name I know) cycles ending up with the oil being diluted woth diesel

 

[bluejasper2]

thanks for replies chaps but could over filling with oil cause a injector problem and not a seal failure some where else ,and what would the
cure be.

 

[Cymrogwyllt]

over fill is very unlikely to lead to injector prob but may lead to seal prob

 

[bluejasper2]

thats what i was thinking normally does the turbo in as well

 

[PaulGooch]

thats what i was thinking normally does the turbo in as well

IMO, you need to get the injectors out and tested. If one is leaking, you need to get the oil and filter changed. (obviously need to get the injector fixed too )

 

[Baddox]

The high oil level may be a symptom not the cause of the problem. If an injector is sticking it will add too much fuel to the engine and as said earlier, some of this will pass out of the cylinder and into the engine. You’ll then be left with a larger volume of “oil” than you started with. The oil/diesel mixture will not be a good lubricant for the engine so if it was mine, I’d sort the problem before running it.
I’m no expert but guess a sticking injector will lead to incomplete burning of the fuel which in turn could would give increased smoke. If this is the case it will also be washing lubricating oil of the cylinder walls and increasing wear.
Another option is a leak from the fuel pick-up pump seal into the engine oil.

If you are concerned about the turbo then the most likely bit to have suffered are the oil seals that when compromised will leak oil past them and into the engine. A lower viscosity oil such as one diluted with diesel will leak more. This will initially show up as blue smoke on start-up an possibly smoke when the engine revs are dropped.

 

[Latestarter1]

hi again, the saga continues
we did what late starter suggested re checked oil took boat out gave it a good run out for a couple of hours, engine running fine no smoke above
2000 revs. came back into marina let engine idle for a while burnning oil again.
friend then had a word with local boat engineer(not nanni engineer)
he said could be leaky injector. but would this just put more fuel in cylinder
and cause black smoke.we have been watching the oil level closely and it has risen about 4mm , this has got us stumped. there are not many engineers in
the north east. the local ones do not seem to be interested.any thoughts will be appreciated (nearest nanni dealer down south)thanks paul.

Stop referring to yard numpties giving second hand infomation as 'engineers' they are technicians, many only deserve the title applied very loosely.

#1 Forget all the rubbish talk regarding injectors injecting too much fuel, I call it Two Gun Tex diagnostics, shooting from the hip!
If injectors are injecting this much fuel you will be hosing the cylinder walls washing off the lubricant and serious engine damage follows in short order. First sign is excessive blow by, after that engine lives for about as long as a Spanish cigarette lighter. People always FAR too ready to rip into injectors. Nice little earner.

#2 You have performed the first step along the road to identifing the problem. Put that infomation in the bank.

#3 Next step is technical. Dip the lube oil and using your suitably calibrated nose and smell it. If you are 'making oil' lube will smell of diesel. If this step proves positive move on.

#4 Your base engine is a pre common rail Toyota which has a licence made (Denso I think) Bosch VE rotary fuel pump. This pump is fuel lubricated, VE is is darn good pump, however on rare occasions front seal can blow out.
I do not have much to do with little puddle jumper motors, however if it has chain as opposed to belt cam drive, failed seal is allowing fuel to flood into front timing case contaminating the lube oil.

#5 Call Nanni technical and find out what is involved in locking engine timing before removing the fuel pump on this motor. Once you understand the proceedure call your nearest fuel pump shop, tell them you have marinised Toyota, not a Nanni engine which is 'making oil' and you suspect pump front seal leakage. They may even have their own mobile tech prepared to come out.

Important piece is getting au fait with the issues in order tp protect yourself from BS.

 

[PaulGooch]

To add to Latestarters post, the T4.155 is based on the 3.0 Toyota Landcruiser/Prado engine, as fitted to the 90/95 series (1996-2002), Engine code 1KZ-TE. It was also used in the Hilux Surf. It's the same base engine as the 4.380 and the 4.390.

His thoughts that it is a Denso VE pump are correct, according to my Landcruiser data. The part number is 22100-67070

The pump is gear driven, which in turn drives the camshaft via a belt.

 

[volvopaul]

If th sump level is increasing then the only 2 ways fuel can enter the crankcase is, if it has a manual lift pump on the side of the block, the diaphram may be split allowing fuel past then into the sump.

If its fitted then as you have smoke at low rpm it may be the case that low fuel pressure in the body of the injector pump is giving poor atomisation at the injectors, due to low static pressure at the cam head, as soon as the revs rise the main injection pump can suck its own fuel in.

I have come across this before on many Nissan/toyota engines and for some reason its always the Jap engines that smoke, another culprit is, underneath the fuel inlet pipe there is sometimes a plastic filter that gets clogged up with dirt, this reduces the flow giving smoke at idle or nea idle speed.

As already said if you sure the sump level is increasing dont use the boat untill you are sure as you will be on your way to a rebuild if thats the case.

Its a while since ive stripped this type of engine but the timing from memory is quite easy as the crank drives the camshaft gear with gears internally lubricated with oil, then the camshaft drives the injection pump externally behind its plastic cover, the marks on the pulleys are straightforward for removal of the pump if req.

The seal can be tested before removal by blanking off the outlet hose and applying pressure at the inlet then watch the gauge loose pressure if the seal has failed.

 

[PaulGooch]

If th sump level is increasing then the only 2 ways fuel can enter the crankcase is, if it has a manual lift pump on the side of the block, the diaphram may be split allowing fuel past then into the sump.

99.99% certain this doesn't have the manual pump Paul.

Its a while since ive stripped this type of engine but the timing from memory is quite easy as the crank drives the camshaft gear with gears internally lubricated with oil, then the camshaft drives the injection pump externally behind its plastic cover, the marks on the pulleys are straightforward for removal of the pump if req.

It's the other way around. The injector pump is gear driven, then a belt from the injector pump drives the cam.

The belt is easy enough to get to and change. The pump should be straight forward to take off too, as it's keyed to the crank gears.

Not a job for a novice though, getting it wrong could lead to a few nicely bent valves.

 

[Latestarter1]

To add to Latestarters post, the T4.155 is based on the 3.0 Toyota Landcruiser/Prado engine, as fitted to the 90/95 series (1996-2002), Engine code 1KZ-TE. It was also used in the Hilux Surf. It's the same base engine as the 4.380 and the 4.390.

His thoughts that it is a Denso VE pump are correct, according to my Landcruiser data. The part number is 22100-67070

The pump is gear driven, which in turn drives the camshaft via a belt.

Thank you Paul, typical nice Toyota. Thinking about it should be a pretty straight forward job, these seals fail for a living when people use bio fuel. Pump does not actually need to go to the pump shop for replacement. New seal for Bosch was about £8, Denso may be twice that, but still not heartbreak stuff.

 

[PaulGooch]

Thank you Paul, typical nice Toyota. Thinking about it should be a pretty straight forward job, these seals fail for a living when people use bio fuel. Pump does not actually need to go to the pump shop for replacement. New seal for Bosch was about £8, Denso may be twice that, but still not heartbreak stuff.

That looks pleasantly simple and cheap for a boat. Getting the pump off doesn't look the end of the World either. Access to the belt is simple enough. I changed the belt on mine a few weeks ago. Looks like a puller will be needed for the belt drive pulley.

Aftermarket belts are available off the shelf, as are fuel (Wix WF8061) and oil (Wix WL7175) filters.

If the OP is interested, i have a series of pictures i took when i did the belt, along with fitting instructions.

Although it says it's for a Hilux, the Toyota manual for the engine is here : http://etoymag.free.fr/manuels2/1KZ-TE.pdf

 

[bluejasper2]

thanks for all the information chaps ,all this stuff is beyond us,
so alfie (his boat) has a pal who is a diesel fitter not marine by the way,is going toget all this information also alfie has a pal who runs fuel injection
buisness so hoping to get injectors tested also.once again thanks again
and i will report back soon paul.

 

[Jim@sea]

I think you have a broken piston ring. Or at least one that is defective and perhaps has worn a groove in the cylinder bore. The fact that your oil level has gone up by 4mm indicates that diesel is going down the cylinder bores. You should have a compression check done on the engine and if one of your compressions is down then its head off and piston out. In the 1960's when I started in a garage workshop broken piston rings occurred more frequently than they do now. A compression test will give you more information.

 

[Latestarter1]

I think you have a broken piston ring. Or at least one that is defective and perhaps has worn a groove in the cylinder bore. The fact that your oil level has gone up by 4mm indicates that diesel is going down the cylinder bores. You should have a compression check done on the engine and if one of your compressions is down then its head off and piston out. In the 1960's when I started in a garage workshop broken piston rings occurred more frequently than they do now. A compression test will give you more information.

Hey Two gun Tex stop trying to frighten the living cr*p out of this poor guy. This is a tough old Toyota motor.

Take a look at Volvopauls post and digest..Engine is sweet, just making oil.

As for compression testing this is gasoline engine stuff and has no place in diesel diagnostics, manufacturers stopped publishing specs years ago. The correct test of diesel engine health is a blow by test.

However if you lack the manometer test kit "The low earth orbit test" works real well, nicely warmed though motor gently unscrew the lube filler cap, gentle puff puff and all is well, if the engine blows filler cap into low earth orbit it is sick, sick, sick knowing which jug is goosed is about as much use as a rubber eye, motor is still goosed.

In this case I suspect carefully working the issues will solve the problem.

 

[Jim@sea]

I am not trying to frighten the owner of this boat, I am just being factual, and where you say that a compression test has no place in diesel diagnostics I respectfully suggest that it is necessary if you have checked everything else. And although the engine as you call it is a "Tough old Toyota Motor" I would remind you that one of the Toyota engines which goes in Toyota Hilux and Surf s, etc are notorious for warping their cylinder heads, which of course a compression test would reveal. I consider that although doing a compression test on a petrol engine is relatively easy as all you have to do is take the plugs out and screw the compression tester in, with a diesel you have to remove the injectors and the compression tester costs a lot more to buy due to the higher pressures it should not deter people from having a compression test done as part of a diagnostic investigation.
You should also remember that a lot of engine manufactures have human beings assembling engines and hand fit piston rings to pistons and in some of the engines which I used to strip (When I was a Hepolite Piston Ring Specialist) apart from broken rings in engines occasionally I came across a pistons where all the piston ring joints were in line so when the engine bore widened due to a bit of wear this allowed unburnt fuel to flow down the line of gaps, whereas rings are supposed to be staggered randomly around the piston.
I am also a great believer in using a Diesel Specialist as recently I had a problem with an engine and my local garage said that it had air in the system so they bled it. No different. Another garage said that it was a faulty turbo, so £500 later. No different. I rang up a Diesel Specialist who when I told him what the make and model of the Injector pump was, said that my type of pump had an inherent fault whereby in cold weather the injector springs snapped on start up. So £200 later with an exchange injector pump my engine was like brand new. The moral of the story is go to a Diesel Engineer, thats where the motor trade mechanics go when they cant diagnose a problem.

 

[Latestarter1]

I am not trying to frighten the owner of this boat, I am just being factual, and where you say that a compression test has no place in diesel diagnostics I respectfully suggest that it is necessary if you have checked everything else. And although the engine as you call it is a "Tough old Toyota Motor" I would remind you that one of the Toyota engines which goes in Toyota Hilux and Surf s, etc are notorious for warping their cylinder heads, which of course a compression test would reveal. I consider that although doing a compression test on a petrol engine is relatively easy as all you have to do is take the plugs out and screw the compression tester in, with a diesel you have to remove the injectors and the compression tester costs a lot more to buy due to the higher pressures it should not deter people from having a compression test done as part of a diagnostic investigation.
You should also remember that a lot of engine manufactures have human beings assembling engines and hand fit piston rings to pistons and in some of the engines which I used to strip (When I was a Hepolite Piston Ring Specialist) apart from broken rings in engines occasionally I came across a pistons where all the piston ring joints were in line so when the engine bore widened due to a bit of wear this allowed unburnt fuel to flow down the line of gaps, whereas rings are supposed to be staggered randomly around the piston.
I am also a great believer in using a Diesel Specialist as recently I had a problem with an engine and my local garage said that it had air in the system so they bled it. No different. Another garage said that it was a faulty turbo, so £500 later. No different. I rang up a Diesel Specialist who when I told him what the make and model of the Injector pump was, said that my type of pump had an inherent fault whereby in cold weather the injector springs snapped on start up. So £200 later with an exchange injector pump my engine was like brand new. The moral of the story is go to a Diesel Engineer, thats where the motor trade mechanics go when they cant diagnose a problem.

Back when I worked for Ford on the Dover new product introduction we revisited diesel engine diagnostics in great detail.

Gasoline engines have a distinct characteristic, once bedded in the compression falls in direct relation to engine wear; therefore compression test is valid health check.

Diesel engines by their nature are very different, after break in the compression stays pretty consistent almost to wear out, in no small part due to diesel engines having pressure balanced piston ring packs as you will know having worked for Hepolite, therefore there is a dynamic element. It is also a matter of high compression and low cranking speeds, obtaining credible #’s is extremely difficult as the number is cranking speed dependant. You will find compression #’s for Ford Dorset diagnostics but not for Ford Dover, we scrubbed them from tech documentation around 1980. I later discovered that CAT and Cummins had come to the same conclusion.

The correct method of testing diesel engine health is to use calibrated orifice and water manometer or a Magnaheilic gauge to test blow by dynamically.

When we run a new engine on the dyno blow by is high until rings bed in, blow by then stabilises, at which point it is OK to pull rated power. Using a compression tester to diagnose leaking head gasket is certainly not a correct procedure. If an engine is TELLING you it is sick believe it, knowing which jug is sick before head has to come off is pointless waste of customers $$, if it is a motor under warranty you get paid not a penny for compression testing.

Now on to my next nausea; ripping injectors out! Volvo and MAN seem to be a bit of exception, but in general provided they are fed a diet of clean fuel they will last to engine overhaul. People are far too ready to pull injectors on a whim. I have seen more problems caused by numpties pulling injectors to perform compression checks than ever existed in the first place. Leaking injector sleeves, white smoke caused by replacing copper injector washers with incorrect thickness, butchered injector pipes the list is endless. Technicians luckily only seem to do it on pump line injector engines cos it is easy, when they are confronted with unit injector motors they are frightened off thank God!

We are on the same page regarding tec’s who do shooting from the hip diagnostics, however diesel pump shops are NOT engineers they are specialist technicians. Not taking anything away from people however the UK seems to be one of the few places where tec’s get such an exalted title, Americans and Germans think it is just one of our silly quirky Brit things.

Returning to the OP, Volvopaul as I said before made the points well, probably because he has gauges in his tool bag too few do!