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Volvo D4 260 loss of top end dies off idle. Hard start in winter

trnsmaster

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Loosing prime / fuel engine dies when put in gear yet is belching black soot

Been fighting loss of top end and hard starting .

On land it starts and idles clean . put in water and it dies in gear like lack of fuel . pump primer it starts. Trying to idle out if it doesn´t die it´s putting out black soot . Try to run it gets to 2200 and compressor cuts out then back in as rpms drop and will keep doing that unless you pull back. boost pressure drops off when compressor kicks out to about 8lb. Turbo boost should be higher. During winter it was really hard start. Might take 15 tries to finally start .

We have installed new turbo. Cam ,crank, boost sensors checked timing. did injector tests. Replaced injectors even though old passes tests. Tried disconnecting mprop sol on pump so it would be max press. Evc read disconnect and set code. charge air cooler checked. Have run off Gerry can instead of tank and racor. Change fuelfilter housing and primer Assy. Have not had anyone put vodia on it . As no error messages.

It´s confusing , not enough fuel to run off idle , but black soot smoke from too much fuel ???

Any ideas. Thanks

 
On a stern drive? Have you checked for any exhaust blockages? Is the kompressor sill kicking in and out at 2200 with the new turbo?
 
On a stern drive? Have you checked for any exhaust blockages? Is the kompressor sill kicking in and out at 2200 with the new turbo?

Sterdrive problem started after output shaft bearing blewup .pulled drive and Pulled motor to fix bearing and install turbo .exhausr wide open
cleaned flywheel and drive plate of rust new crank sensor
 
So you still have the issue you described with the new turbo? So you are still not making boost from the Turbo? Have you checked the aftercooler for blockages? It sounds a bit like you might have an intake blockage. That will drop the turbo boost, make hard starting etc. Need to find out why you haven't got boost from the Turbo. An intake blockage would probably give you most of the symptoms you have. Hard to imagine how you block the intake though unless a rag was left or sucked into the intake.
 
So you still have the issue you described with the new turbo? So you are still not making boost from the Turbo? Have you checked the aftercooler for blockages? It sounds a bit like you might have an intake blockage. That will drop the turbo boost, make hard starting etc. Need to find out why you haven't got boost from the Turbo. An intake blockage would probably give you most of the symptoms you have. Hard to imagine how you block the intake though unless a rag was left or sucked into the intake.

Yes problem still there, boost guage reads 16 lbs from compressor but only 3-5 after compressor cuts out which would be turbo . This on land no load , engine turns up to 3700 on land no load. Everybody says air but if compressor boost gets thru why not turbo ? When engine was out and turbo removed I checked for debris in charge air cooler - none found . Tech said sock in air filter box could come apart and clog . Found a tube look like noise reducer in air filter box so removed that. Checked airbox door for closing when compressor on and it sealed. There was good amount of air flow from hose coming off crankcase vent filter to air box. Don't know what's normal for that .
tried to inspect old turbo but couldn't separate halves. Was no wobbles or in/ out play . Clearances didn't look different from replacement. It was only a few trips before this that hose clamp broke on hose from turbo to charge air and made horrific noise from air getting out hose . So turbo was good at that time .
we had changed to walker airsep reuseable air filter so we reran all tests without filter.
should turbo have full output if engine isn't under load ?
Thanks again for your help
 
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No the turbo won't make much boost without a load. Can you check the boost levels during a sea trial? The kompressor kicking in and out is usually due to low turbo boost. The kompressor is belt driven and will make boost even with an exhaust or intake restriction.Might be down a little, but will make boost. The turbo is exhaust driven and the boost it makes is more affected by any restrictions in exhaust or intake. You could try disconnecting the pie from the Turbo intake to the ai filter and try a quick run. If it still won't spool up like that then you either have a leaky intake lowering your boost, exhaust leak before the turbo, or an exhaust restriction (or faulty new turbo)
 
No the turbo won't make much boost without a load. Can you check the boost levels during a sea trial? The kompressor kicking in and out is usually due to low turbo boost. The kompressor is belt driven and will make boost even with an exhaust or intake restriction.Might be down a little, but will make boost. The turbo is exhaust driven and the boost it makes is more affected by any restrictions in exhaust or intake. You could try disconnecting the pie from the Turbo intake to the ai filter and try a quick run. If it still won't spool up like that then you either have a leaky intake lowering your boost, exhaust leak before the turbo, or an exhaust restriction (or faulty new turbo)
Almost seems like faulty replacement turbo having checked air passages thanks
 
Was it a new or used turbo? You can check a turbo by measuring the gap between the vane tips and the exhaust housing which is where you get problems on a lot of Volvo turbos on out-drive boats. Other than that, check for smooth bearings and any play.
 
Was it a new or used turbo? You can check a turbo by measuring the gap between the vane tips and the exhaust housing which is where you get problems on a lot of Volvo turbos on out-drive boats. Other than that, check for smooth bearings and any play.

cant find spec in manual for blade to housing clearance .
old turbo has .006/.008 clearance exhaust side and .006 output side.
the bearings are smooth , no updown or side to side play.
shop air gets it spinning.

did find charge air boost pressure chart and at the 2200 rpms that compressor cuts out leaving 8 lb boost doesn't seem like it's off from chart !

do you know blade clearance spec ??
Thanks a bunch
 
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That 'hunting' when the Kompressor hands off to the Turbo is a real common Volvo problem. I have dealt with it on a couple of engines and it was always the exhaust side vane tip clearances due to corrosion in the housing. It is so common that a company near me had inserts CNC'd up so they could mill out the old housing and weld in the inserts for a fraction of the cost that Volvo wanted for a repair. None of that was on a D4 though, but the issue seems very similar. I haven't got and tip clearance figures sorry. If the engine rpms suddenly won't climb when the kompressor cuts out is almost has to be a boost problem I think. Otherwise why do the rpms drop back? Maybe the D4 has something in the electronics that knows whether it is on Turbo or Kompressor and alters the fueling, but I haven't herd of that being the case.
You mentioned earlier about a lot of air from the crankcase vent. Some blowby is normal, but if excessive it could indicate a compression issue. That probably still wouldn't explain the Kompressor hunting etc. Did you ever do a compression test?
 
That 'hunting' when the Kompressor hands off to the Turbo is a real common Volvo problem. I have dealt with it on a couple of engines and it was always the exhaust side vane tip clearances due to corrosion in the housing. It is so common that a company near me had inserts CNC'd up so they could mill out the old housing and weld in the inserts for a fraction of the cost that Volvo wanted for a repair. None of that was on a D4 though, but the issue seems very similar. I haven't got and tip clearance figures sorry. If the engine rpms suddenly won't climb when the kompressor cuts out is almost has to be a boost problem I think. Otherwise why do the rpms drop back? Maybe the D4 has something in the electronics that knows whether it is on Turbo or Kompressor and alters the fueling, but I haven't herd of that being the case.
You mentioned earlier about a lot of air from the crankcase vent. Some blowby is normal, but if excessive it could indicate a compression issue. That probably still wouldn't explain the Kompressor hunting etc. Did you ever do a compression test?
It wasn't blow by it was door stuck on air box .but still no improvement. Finally had computer scan with vodia .
It showed cyl 1&4 low "compression "cyl 2&3 perfect.
now it's not a reel comp test. Somehow measures piston speeds to give reading. So swapped injectors from good to bad cyl, same results.
took an old injector made an adapter to do compression test.
cyl 1&2= and cyl 3&4 =. But there's a 50lb difference between 1/2 to 3/4. Doesn't match vodia results at all.
next tried to do air leak down test . Used my injector adapter to air up cylinders at tdc on each . Didn't hear leaks and least amount of air wanted to spin the crank . Had to hold with bar.
got engine back out to check timing reluctor wheel on cam for proper index. And they wanted charge air cooler cleaned . I had checked air cooler when replacing turbo .
but now find new turbo has been dumping oil into charge air cooler !
dealer says new turbo won't seal up if not making boost???? My old turbo came off bone dry on air cooler side !

dont know where to go from here.... thanks

motor has 900 hrs how many hrs are D4 good for ?
 
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