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  #11  
Old 11-12-2007, 10:02 AM
Disco Mike's Avatar
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Default RE: engine knock

I still think you need to find out while the oil light isn't working and do an oil pressure test at both idle and 2000rpm's as well as cold and at operating temp.
 
  #12  
Old 11-12-2007, 02:26 PM
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Default RE: engine knock

ORIGINAL: Disco Mike
I still think you need to find out while the oil light isn't working and do
an oil pressure test at both idle and 2000rpm's as well as cold and at operating temp.
Would it not be wiser do these diagnostics with as little engine running as possible? Why take any greater a risk with damage than necesssary at this stage? The oil test showed he has oil pressure so that is NOT the cause of the knock. After that, further meaurements would for pump wear (which would not cause a knock) or a bad blockage.

Standard oil pressure tests on this vehicle is done with running temperature oil at 2400-2600 rpm depending on which Manual you like.

James

 
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Old 11-12-2007, 03:09 PM
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Default RE: engine knock

And near 30 experience in the shops says you test at idle and 2000 rpm's both when cold and at operating temp.
Manuals may very but old experience usually wins out.
 
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Old 11-13-2007, 03:12 AM
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Default RE: engine knock

ORIGINAL: Disco Mike

And near 30 experience in the shops says you test at idle and 2000 rpm's both when cold and at operating temp. Manuals may very but old experience usually wins out.
I hope not. Those shops would probably not fully understand what they are dealing with. The Factory Manuals, (not the stuff people buy from Haynes or Amazon.com) are made very detailed and are uniformly excellent..subject to keeping them updated with Service Bulletins. If a dealer invents his own tests and wants to rely on them, he should do that in carefully conjunction with LR or keep it VERY quiet.

On a high volume low pressure system, you have to have a base datum to compare or the only thing random testing without parameters will prove is that there is pressure..and nothing more than that.

All post Sd1 engines had the same test and pressure until 1996. These models had their oil pump drive gear turned by a female adapter at the end of the distributor. However, the timing cover changed with the 4.0/4.6s, the distributors were removed and the pumps are driven off the crankshaft.

James
 
  #15  
Old 11-13-2007, 06:52 AM
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Default RE: engine knock

So, I guess when Rover sent to to all those classes, they didn't know what they were talking about, that's good to know.
 
  #16  
Old 11-13-2007, 08:04 AM
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Default RE: engine knock

ORIGINAL: Disco Mike

So, I guess when Rover sent to to all those classes, they didn't know what they were talking about, that's good to know.
Do you mean LR tech sessions and training? I can tell you that they are not taught anything contrary to the Land Rover Factory Manuals they are told to rely on. Admittedly, the most thorough training cannot guarrantee a good mechanic will be the result.

In any event, there is a problem we have been asked to address involving an audible engine knock. We have been able to determine that there is oil pressure...even high oil pressure but it was taken at idle and the oil was cold. Nonetheless, that would normally be sufficient to prove that oil circulation failure is not the cause of the knock saving the possbility of a serious blockage (which would then make it dangerous to run the engine at all). However, you believe that the motor should now be brought up to running temp and oil pressure should be more deeply confirmed both at idle and 2000 rpm. If you have oil pressure figures for those two rpms, it would help? I have not seen anything on that.

As well, you believe the knock will resolve itself if the engine oil is drained and replaced with ATF and then run, despite the knocking, to flush the engine.

This is your forum and I respect that. Let's see what happens with that route.

James
 
  #17  
Old 11-15-2007, 08:45 PM
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Default RE: engine knock

ok here's where i'm at at the moment. my dad's friend (theretired mechanic) had some mechanics he knows listen to the engine. they said it didn't sound like main or big end bearings. their best bets were lifters or possible a bent push rod.

i drained the 5w30 out thati had put in and replaced it with 15w40 and oil stabilizer. i then ran the engine up to temp (the knock is still there but much quieter). i checked the oil pressure cold and at running temp at idle, at 2000 rpm, and at 2500 rpm. the pressure was consistently between 30 and 32 psi.

i also connected the oil sending unit wire directly to the negativebattery terminal. this made the light come on when i turned the key on. i must not have gotten a good ground lasttime i checked it. i guess i need a new sending unit.

i have also pulled plug wires one at a time to see if cutting out a particular cylinder changed the noise. it did not. according to the shop manual, if this is the case they suggest checkingthe securiy of the crankshaft pulley and flywheel. anybody know what the best way to do this is?

thanks again everyone,

trevor

 
  #18  
Old 11-16-2007, 06:36 PM
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Default RE: engine knock

ORIGINAL: jtreider
ok here's where i'm at at the moment. my dad's friend (theretired mechanic) had some mechanics he knows listen to the engine. they said it didn't sound like main or big end bearings. their best bets were lifters or possible a bent push rod.
i drained the 5w30 out thati had put in and replaced it with 15w40 and oil stabilizer. i then ran the engine up to temp (the knock is still there but much quieter).
You are doing great. BTW, a lifter noise is traditionally referred to as a tick tick tick or a clackety clack where a bearing or push rod is more of a knock. Which do you have?

The extra zinc phosphate in the 15W40 is helping. It will only last 2500-3000 miles. You should consider stocking up on http://www.zddplus.com It is becoming very difficult to get the older oils your engine was made for in the US and it will get worse. Try 2 oz of that stuff. Not to worry. Our team have had it lab analyzed and it is ok.

ORIGINAL: jtreider i checked the oil pressure cold and at running temp at idle, at 2000 rpm, and at 2500 rpm. the pressure was consistently between 30 and 32 psi..
Now that IS weird. But you SHOULD be at 30-32 but with hot oil at 2400rpm. AND, I don't use oil coolers and that would lift the pressure at lower rpm. Let me check this one out with my LR tech side.

ORIGINAL: jtreider
i also connected the oil sending unit wire directly to the negativebattery terminal. this made the light come on when i turned the key on. i must not have gotten a good ground lasttime i checked it. i guess i need a new sending unit.
Worth it. Even if you are wrong, they're cheap. Mind you, if you were wrong and there is no oil pressure, the engine have loudly expired by now.

ORIGINAL: jtreider
i have also pulled plug wires one at a time to see if cutting out a particular cylinder changed the noise. it did not. according to the shop manual, if this is the case they suggest checkingthe securiy of the crankshaft pulley and flywheel. anybody know what the best way to do this is? trevor
Personally, I think both are fine but no harm in testing if you have the time.

The crankshaft pulley is afixed to the damper. It is held to the crankshaft with the highest torque of any bolt on the engine..200lb/ft. To check, you must get a torque wrench.

First check the flywheel. You cannot check the bolts of the flywheel without removing the engine and I don't like that much. There is, however, two ways of getting to the flywheel and trying to move it in or out. One is to remove the starter (disconnect the battery first!) and the other way is to remove the access plate at the bellhousing. Once you see the flywheel, try pushing it inward. That is the best you can do easily.

Now put the engine in gear and have a friend hold a large screwdriver to hold the flywheel immobile using the teeth of the ring gear. Take your torque wrench, adjust to 190lbs and fit it with the appropriate socket onto the big crankshaft pulley bolt. If you have insufficient room, you will have to remove the belt, and then the little bolts on the pulley section to pull it off.

Once on the bolt, you will probably need an extension for the torque wrench to reach 190 lbft

James
 
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