Author Topic: Diesel knock? - NOW FIXED!!!!!!!  (Read 86747 times)

Reply #15March 16, 2011, 08:18:58 pm

Mark(The Miser)UK

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Re: Diesel knock?
« Reply #15 on: March 16, 2011, 08:18:58 pm »
I sold an engine to a friend for his caddy and gave him help setting it up.

It knocks quite heavily  ::)

I changed the pump timing and still the knock remained, I even swung the pump across it's timing limits while the engine was running - no real change.

He swapped the injectors for known good ones - still knocking.

Fearing the worst I missed out on Sunday lie in and was down at his garage early, I pulled the head - very clean, slight carbon build up on number 3 but as expected.

Now pulled the sump, nothing in the oil, dropped the connecting rod caps and pulled the pistons out to check

Still nothing  ???

It's not lifters as it's not 'that' type of ticky noise, it's more clack.


Any ideas people? It starts and runs fine. Just noisy.

It can only be pump now surely?

It could be the valves kissing the pistons, or getting very close to them.
Nearest point is not TDC  but a little either side, as the piston chases the exhaust valve before it closes BTDC and as the inlet chases the piston ATDC.

The sound echoes out the manifolds. Worsened  by skimming of head, naturally...

My engine has been doing it for 30,000miles :-[

Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #16March 17, 2011, 12:52:47 am

fatmobile

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Re: Diesel knock?
« Reply #16 on: March 17, 2011, 12:52:47 am »
Rod pins feel sloppy in the pistons?
Tornado red, '91 Golf 4 door,
with a re-ringed, '84 quantum, turbo diesel, MD block

Reply #17March 17, 2011, 06:16:09 pm

regcheeseman

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Re: Diesel knock?
« Reply #17 on: March 17, 2011, 06:16:09 pm »
Gudgeon pins and small ends are fine - that was my no1 suspect after timing and injectors were eliminated.

Quote
It could be the valves kissing the pistons, or getting very close to them.

I'd expect to see some witness marks - there is nothing

No 2 piston has a little dent on one edge, looks like something solid entered the chamber made two dents before being spat out, there's a corresponding mark on the cylinder wall - but no damage, not significant.

Reply #18March 18, 2011, 12:14:26 am

maxfax

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Re: Diesel knock?
« Reply #18 on: March 18, 2011, 12:14:26 am »
Off the wall question, is this engine hydro or mech lifter???

Reply #19March 18, 2011, 05:23:11 am

Mark(The Miser)UK

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Re: Diesel knock?
« Reply #19 on: March 18, 2011, 05:23:11 am »
I sold an engine to a friend for his caddy and gave him help setting it up.

It knocks quite heavily  ::)

I changed the pump timing and still the knock remained, I even swung the pump across it's timing limits while the engine was running - no real change.

He swapped the injectors for known good ones - still knocking.

Fearing the worst I missed out on Sunday lie in and was down at his garage early, I pulled the head - very clean, slight carbon build up on number 3 but as expected.

Now pulled the sump, nothing in the oil, dropped the connecting rod caps and pulled the pistons out to check

Still nothing  ???

It's not lifters as it's not 'that' type of ticky noise, it's more clack.


Any ideas people? It starts and runs fine. Just noisy.

It can only be pump now surely?



Reg,
If you can take the vehicle out for a drive, then on a quiet stretch [might still be one in Devon way]with the clacking happening, turn off the engine, whilst still in gear and see if the sound disappears, if it goes, then its fuel, if it doesn't then it's 'mech'
;D
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #20March 18, 2011, 08:16:52 am

regcheeseman

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Re: Diesel knock?
« Reply #20 on: March 18, 2011, 08:16:52 am »
Quote
Off the wall question, is this engine hydro or mech lifter???

hydro


Mark/Blackdogvan

I'll try that test when it's rebuilt, the workshop is right next to the only real dual carriageway in North Devon. A well known test strip.

Reply #21March 18, 2011, 12:21:35 pm

sdwarf36

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Re: Diesel knock?
« Reply #21 on: March 18, 2011, 12:21:35 pm »
If you crack the fuel lines one at a time, you will take the load off that cylinder( no fuel= no fire=no load) -you can see if the noise changes.
 To check for the flywheel bolts, put the car in gear-have someone stand hard on the brakes-and go back+ forth with the crank bolt. Look to see if the flywheel moves the same amount as the crank bolt.
 Also-are #1+4 piston up the same amount? (just thinking possible prior bent rod)
91 Jetta on WVO na / td swap in progress.

 "VW happiness is having 4 working door handles."

Reply #22March 18, 2011, 06:34:34 pm

regcheeseman

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Re: Diesel knock?
« Reply #22 on: March 18, 2011, 06:34:34 pm »
Quote
If you crack the fuel lines one at a time, you will take the load off that cylinder( no fuel= no fire=no load) -you can see if the noise changes.
 To check for the flywheel bolts, put the car in gear-have someone stand hard on the brakes-and go back+ forth with the crank bolt. Look to see if the flywheel moves the same amount as the crank bolt.
 Also-are #1+4 piston up the same amount? (just thinking possible prior bent rod)

Rods are fine, already done the injector test before tearing the motor down.

I'll do the flywheel test.

Reply #23March 19, 2011, 02:21:38 am

rdezsofi

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Re: Diesel knock?
« Reply #23 on: March 19, 2011, 02:21:38 am »
I guess you have it torn apart.....how are this pistons and bore, as far as measurements? I'm thinking severe piston slap maybe??? Did you do a compression check prior to teardown? It might just have extremely high compression. (Head surfaced, etc, etc.)

Reply #24March 19, 2011, 05:26:50 am

Mark(The Miser)UK

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Re: Diesel knock?
« Reply #24 on: March 19, 2011, 05:26:50 am »
Quote
Off the wall question, is this engine hydro or mech lifter???

hydro


Mark/Blackdogvan

I'll try that test when it's rebuilt, the workshop is right next to the only real dual carriageway in North Devon. A well known test strip.

Hi,
 I'd just like to apologise to Blackdog van , I didn't  spot his [I assume a chap :o] prior post detailing similar technique. ::)
"I must read the threads more closely  I must read...."

In my defence, my technique removes even more fuel ;D
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #25May 24, 2011, 03:45:25 am

regcheeseman

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Re: Diesel knock?
« Reply #25 on: May 24, 2011, 03:45:25 am »
It's got me beat! looks like the turbo seal is giving up the game too.

We're going to fit another engine and this one will get an autopsy at some point.

Reply #26May 24, 2011, 05:23:39 am

Mark(The Miser)UK

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Re: Diesel knock?
« Reply #26 on: May 24, 2011, 05:23:39 am »
It's got me beat! looks like the turbo seal is giving up the game too.

We're going to fit another engine and this one will get an autopsy at some point.

Don't you hate that.

I'm thinking my only solution in my case is to remove the 'unleaking head' and skim the outer exhaust valves.
I too had bought small end and big end bearings, expecting[hoping] to find a rogue one; but no play detected so the kits remain in reserve.
Did the sound continue with no fuelling?
Mark-The-Miser-UK

"There's nothing like driving past a bonfire and then realising; its my car on fire!"

I'm not here to help... I'm here to Pro-Volke"

Be like meeee: drive a Quantum TD
 ...The best work-horse after the cart...

Reply #27May 25, 2011, 08:34:41 am

carrizog60

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Re: Diesel knock?
« Reply #27 on: May 25, 2011, 08:34:41 am »
my aaz(well 1y with turbo) is now making a tim tim tim sound,not clatter...
not to highjack the thread sorry but can anyone help?
timed to 1.00mm,with aaz injectors and 1.6 gtd fuel pump
vw golf gti G60--vw passat 1.9td gt2052v
yamaha vmax 1200- yamaha tdm 850
Portugal

Reply #28May 26, 2011, 05:43:02 am

regcheeseman

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Re: Diesel knock?
« Reply #28 on: May 26, 2011, 05:43:02 am »
FIXED IT  ;D

I can't take any credit for doing so, it was only spotted by a mechanic who had a Toyota Hilux doing similar.

Basically despite have the injector lines and pump removed at least four times, no-one noticed that they were wrong.

The previous owner had managed to bend them to fit in a different sequence. They didn't look obviously bent and offered themselves up to the head quite naturally.

A quick switch around and it's running sweet as!

It's surprising that it started, idled and run quite happily in it's mixed up state.
« Last Edit: May 26, 2011, 05:49:46 am by regcheeseman »

Reply #29May 26, 2011, 06:05:09 am

macka

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Re: Diesel knock? - NOW FIXED!!!!!!!
« Reply #29 on: May 26, 2011, 06:05:09 am »
well its fixed and all is well. That is funny that it ran
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