Engine extremely noisy when hot
Discussion
Normally my engine sounds fine... there is no smoke or unusual noise, no matter what RPM the engine is running. But as soon as oil and water temperatures reach 90 degrees it sounds like some valves getting hammered really hard. If I let the engine cool done for some time again, the noise is gone again. First thought it might be the typical chain rattling thing.. but it really sounds more like the valves.
Can it be, that the oil get's so thin at some temperature, that it does not propperly protect the chims/Fingerfollowers anymore?
Already asked some engine guy about checking the chims.. but he said, then the knocking noise wouldn't be there just at high temperatures!? But maybe some one here knows better?
Can it be, that the oil get's so thin at some temperature, that it does not propperly protect the chims/Fingerfollowers anymore?
Already asked some engine guy about checking the chims.. but he said, then the knocking noise wouldn't be there just at high temperatures!? But maybe some one here knows better?
Mine did/does that. Strong Tappety noise but only when warmed up. Turns out its a follower and lobe which is worn due to the usual lack of oil. Need to get the money together for a rebuild now not good. I hope yours is not the same. Easy to take the top cover off for a look see though. Good luck.
Doesn't sound good.
I had a rattle I thought was coming from the engine but turned out to be rattling break pads, try holding a length of copper pipe(1 meter length) at the engine and put the other end up at your ear it will help to identify where the noise is coming from. hold the pipe at the cam cover, then at the front where the chains are then near the bottom. It sounds a bit mad but it does work!!
I had a rattle I thought was coming from the engine but turned out to be rattling break pads, try holding a length of copper pipe(1 meter length) at the engine and put the other end up at your ear it will help to identify where the noise is coming from. hold the pipe at the cam cover, then at the front where the chains are then near the bottom. It sounds a bit mad but it does work!!
Well, I finally took my courage in both hands and removed the camcover for the first time, expecting the worst. But to my surprise, all lobes and tappets looked nice... except for one having some very slight grooves... nothing bad. I then measured the clearance of all valves. Here is the list.... seems like only one intake valve on Cyl.6 is out of tollerance. (All measured in mm)
Cyl.1:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,20
Cyl.2:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,20
Cyl.3:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,25
Cyl.4:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,25
Cyl.5:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,20
Cyl.6:
intlet: 0,05 and 0,10
outlet: 0,20 and 0,25
So, in thou this is an average of 4-5 for the inlet and 8-10 for the outlet, what should still be kind of ok.
There are of cause the typical scratchmarks from the chain on the camcover.... but as I had this rattle before, I'm pretty sure that the noise is not caused by the chain. And it also can't be the brake pads, as the noise is also there, when keeping the brake-pedal pushed down. It's definately coming from the upper part of the engine.
I talked again to my engine guy and we were trying to find an explanation... and he also thinks, that it might just be oil related... so if the oil reaches some degree, the oilfilm between valves and tappets loses to much viscosity, what allows the tappets to hit the valves nearly unprotected and undamped. What on the other side causes the sewing machine noise.
But what to do now!?.... Oil pressure is always fine... it is even at the higher end of pressure ranges reported here as "normal". So using thicker oil might cure that noise but oilpressure would raise.
Currently I'm running Elf excellium 5W-40 NF what normally should be a good match for the engine....
Should I try 10W-40? Or what other options might there be??
Cyl.1:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,20
Cyl.2:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,20
Cyl.3:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,25
Cyl.4:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,25
Cyl.5:
intlet: 0,10 and 0,10
outlet: 0,20 and 0,20
Cyl.6:
intlet: 0,05 and 0,10
outlet: 0,20 and 0,25
So, in thou this is an average of 4-5 for the inlet and 8-10 for the outlet, what should still be kind of ok.
There are of cause the typical scratchmarks from the chain on the camcover.... but as I had this rattle before, I'm pretty sure that the noise is not caused by the chain. And it also can't be the brake pads, as the noise is also there, when keeping the brake-pedal pushed down. It's definately coming from the upper part of the engine.
I talked again to my engine guy and we were trying to find an explanation... and he also thinks, that it might just be oil related... so if the oil reaches some degree, the oilfilm between valves and tappets loses to much viscosity, what allows the tappets to hit the valves nearly unprotected and undamped. What on the other side causes the sewing machine noise.
But what to do now!?.... Oil pressure is always fine... it is even at the higher end of pressure ranges reported here as "normal". So using thicker oil might cure that noise but oilpressure would raise.
Currently I'm running Elf excellium 5W-40 NF what normally should be a good match for the engine....
Should I try 10W-40? Or what other options might there be??
Edited by votan on Thursday 19th July 20:10
Well, I still have the old original pressure gauge that is known for showing wrong higher values. I guess I will just get a new oil filter, throw in some 10W-40 today, renew one shim and see what will happen.... If I can get all parts and stuff that fast!?
As for the pressure my gauge usually reports..... cold about 80 to 75 psi hot about 20 to 25 psi what nromally should be good values!? Let's see what it reads with 10W-40....
As for the pressure my gauge usually reports..... cold about 80 to 75 psi hot about 20 to 25 psi what nromally should be good values!? Let's see what it reads with 10W-40....
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