V6 - knocking in engine when not under load (video)

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Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Tue Apr 25, 2017 12:44 pm

It may be easier to drop down RD. It may well be something they have come across before. They would just need to listen to it.
bourne2bongo
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Re: V6 - knocking in engine when not under load (video)

Post by bourne2bongo » Tue Apr 25, 2017 3:44 pm

So RD is a 6 mile (25 minute) drive away. Not sure driving it there is such a good idea.

New development with the knocking: still quiet from a cold start but I noticed (with the engine cover removed) that oil is being squeezed out of the sump seal (see video) under tick-over. This dripping (squeezing out) slows and then stops as the engine warms up, which is when the knocking noise starts. Could this be anything to do with the wrong oil

https://youtu.be/EEMtfWdMQ5E

Had a good listen to the tensioner pulleys with the stethoscope. Although a little grindy there wasn't any knocking.

Is there a chance the noise could from be the water pump? Looks like one was fitted in Feb this year...
V6 '96 MPV and loving it!
Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Tue Apr 25, 2017 3:54 pm

That could indicate crankcase pressure pushing the oil out or over filled with oil.
Not oil type related.
If you remove the oil filler cap ( cover it with a cloth coz its messy) does the dripping stop?
What mileage are you at does the motor smoke at all?
Did you do the oil change?
I would say a six mile run would be acceptable if you could do it in light traffic and keep the revs as low as possible bearing in mind you did the run back to Bournemouth. No guarantees though. So maybe book it in and run it down in the evening for next day?
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Re: V6 - knocking in engine when not under load (video)

Post by rita » Tue Apr 25, 2017 4:10 pm

bourne2bongo ,when you tested the sump bolts/setscrew did you need to tighten any of them?

I just remembered that this engine may also have a oil restrictor/baffle plate.

And has been said, often peeps overfill the engine with oil (unintentionally) when they have a severe engine noise thinking ( hoping)it will solve the problem.



Good Luck
Last edited by rita on Tue Apr 25, 2017 4:14 pm, edited 1 time in total.
Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Tue Apr 25, 2017 4:12 pm

Roughly what sort of mileage have you covered since its purchase was it a private sale and where the sellers named in the log book?
bourne2bongo
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Re: V6 - knocking in engine when not under load (video)

Post by bourne2bongo » Tue Apr 25, 2017 4:32 pm

Leak is not coming from the sump, but instead from behind the timing belt (crank shaft seal?).

I noticed something in the last video, cleaned up the sump with a rag and gave it another spin. Sure enough, after 30 - 60 seconds, a trickle of oil dripping down from behind the crank shaft pulley. Will post video once it uploads for others to see.

Bongolia - Private sale, owners name in log book (matches MOT history, V5 and receipts for last 2 years). I checked pressure on the oil filler cap: no vacuum at all, or breathing ... seems to be no pressure issue there. ~170,000km on the clock. Motor doesn't seem to smoke.

EDIT: travelled over 1,100km since buying.

Rita - I haven't put any oil in since picking up the keys. Change was done by previous owner. Level is still good but haven't driven much since knocking started - was a little high when I picked her up but didn't seem excessive. Would adding more oil _mask_ the noise temporarily?

Still not done the oil pressure test but if seals are gone on crank shaft (?) I guess pressure test would fail anyway?
V6 '96 MPV and loving it!
rita
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Re: V6 - knocking in engine when not under load (video)

Post by rita » Tue Apr 25, 2017 4:36 pm

No, you need to do an oil pressure test ASAP.
Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Tue Apr 25, 2017 5:15 pm

That all sounds good had me worried for a bit!
I still think your best option is to get it to someone who can sort this for you. You have a few variables there that need to be looked at not least the crank seal. That seal may have an influence on the pressure reading but more importantly oil could have contaminated the cam belt. The fact that you have no puffing is a positive though.
If you are concerned about driving it that distance you are OK to tow it. Keep the speed 《30 in neutral and maybe rest up for ten mins or so in between.Once they have done the seal and belt (if needed) get the oil system flushed out then see what you have.
bourne2bongo
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Re: V6 - knocking in engine when not under load (video)

Post by bourne2bongo » Tue Apr 25, 2017 8:05 pm

Here's a short video of the oil leak emerging from behind the drive belts. I SOOO nearly missed this.

https://youtu.be/WhKbXq7yPdY

Have ordered an oil pressure testing kit - will collect tomorrow and report back the result here.

If that looks good then I'll get her in to Poole for a check with the garage, and then book in for new cam belt and to overhaul seals. If not, I'm not sure where to start :?

Keep them crossed for me folks!
V6 '96 MPV and loving it!
Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Tue Apr 25, 2017 8:08 pm

Crossed :D
bourne2bongo
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Re: V6 - knocking in engine when not under load (video)

Post by bourne2bongo » Tue Apr 25, 2017 8:10 pm

Thanks! :wink:
V6 '96 MPV and loving it!
Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Tue Apr 25, 2017 8:19 pm

45-75 psi engine hot @ 3000 rpm.
bourne2bongo
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Re: V6 - knocking in engine when not under load (video)

Post by bourne2bongo » Wed Apr 26, 2017 10:29 am

I gave Roy at R D Motors a call this morning and we spoke for a while.

He reckons that the best place to start is to have a listen to the noise. That and an oil pressure test. So i'll be taking the van to him Friday lunchtime.

Keeping everything crossed now ...
V6 '96 MPV and loving it!
Bongolia
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Wed Apr 26, 2017 10:37 am

bourne2bongo wrote:I gave Roy at R D Motors a call this morning and we spoke for a while.

He reckons that the best place to start is to have a listen to the noise. That and an oil pressure test. So i'll be taking the van to him Friday lunchtime.

Keeping everything crossed now ...
Good call. [-o<
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Re: V6 - knocking in engine when not under load (video)

Post by Bongolia » Thu Apr 27, 2017 9:56 pm

On another thread Bournetobongo but thinking of your leaky front oil seal I wonder if you may have a similar issue?
http://igmaynard.co.uk/bongo/forum/post ... =3&p=69094
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