VR6 Temporary Death Clatter!!??

[Fanjita 1]

Hi all,

 

My VR has been off the road for 3-4 months now, but I have been firing it up and letting it warm up whenever I can. Last time I did this was just over a week ago when I was home last, sounded fine aside from a little bit tappety when warm but it always has and never got worse.

 

Yesterday, in light of the fact that I can finally put it back on the road and take it to my place of study with me, I fired it up getting it ready for the MOT. At first it didn't sound rough at all, in fact it sounded quieter than it normally does when cold, the charateristic unhealthy rattle from cold wasn't there this time!

 

So I let it continue to warm up and walked off and left it. When I returned it was making a pretty nasty clatter, at the same frequency as the tappet noise which has always been present. This was a lot louder than normal, likened to someone tapping the top of the engine with a medium sized hammer.

 

Thinking the worst, I was a bit baffled as to why such a noise would just develop without the car being used. I decided to leave it running to see if it got worse/better. At the time we were trying to sort the alignment of the headlights out, so I got tired of hearing it and switched the engine off. I have heard a similar noise on someone's recording on here, and the consensus from other forum members was that it was a pretty terminal noise and needed fixing asap!

 

Anyway after we finished the work I fired it up and let it run some more, leaving it idling and walking away for a few minutes. Upon my return the unhealthy clatter had completely gone, and the slight tapping was there in it's place. This has left me a bit confused!

 

So I'd like people's opinions on this, sorry i know it's a bit of a read but I thought I'd set the scene before i describe what happened. I was very close to recording it but when I returned with my camera the sound had gone. I'm planning a 170 mile drive down to my place of residence at the end of the week, and I'm really hoping that something bad won't happen!

 

Could this have been caused by oil starvation to a tappet in the head? We tried to locate the source of the noise and it did appear to be at the top end but I know there is still a chance i could have problems with bottom end shells or such like. It's been a flawless engine runs perfectly and pulls fine when i tested it today, just got a bit concerned with this noise and my bringing it back on the road.

 

Thanks in advance

[pete_griff 0]

sounds like a bit of an odd one...

 

strange things can happen to carswhen they sit still for a while.

 

you shouldn't get airlocks per-say for more than a couple of seconds in the oil system. however, when people have rebuilt engines etc, they have sometimes had issues with the tappets taking quite a while to quieten down.

 

if it's been sat stationary for a while without a good hard run out with the oil sloshing around everywhere as it's designed to, then you could possibly be suffering from the same issue.

 

i would say give it an oil and filter change and carefully inspect the old filter. then run it properly on the road for a while and monitor the situation.

chances are (hopefully) that it will just "go away"

i would sy that's the best course of action for you right now.

 

if the symptoms persist or your old oil filter looks like a glitter factory then you know it's something more sinister

[Kevin Bacon 5]

Golden rule: Never warm up an engine in storage by just idling it. If you're going to start an engine, drive the car immediately and get it fully up to temperature.

 

Rich warm up fuelling mixed with water (condensation in cold engines) is incredibly acidic and is what causes 90% of all engine wear and what rots exhaust systems from the inside out. It's sulphuric acid.

This why you should get in and drive immediately and get it hot as soon as.....

 

And to labour the point even more, never a buy a low mileage 'minter' from a pensioner. The oil in those engines never gets hot enough to evaporate moisture, bearing in mind water doesn't evaporate until 100 deg C :wink:

Always buy the motorway mile muncher instead and save yourself some cash too.

 

If a car is in storage, it's best not to start it. So long as it's sealed and with spark plugs and a closed throttle, no air will get in there and rust the bores. If you're concerned, just simply crank it over periodically with the ECU disconnected.

 

Anyway, regarding you noise, it does sound like a tappet to me although it's hard to diagnose noises on a computer screen :D Both the chain tensioner and oil pump have non-return functions to maintain pressure when the engine's off, but tappets do not, so they can easily lose oil pressure and take a while to fill up.

 

All you can do at this stage is take it for a drive and see if the noise goes permanently.

[Fanjita 1]

Thanks a lot guys.

 

What you've said is reassuring, it is indeed a strange condition that I as of yet have not seen or read about before.

 

I'm glad to say that today I took the VR down to the MOT station to get it's certificate, and there was not a hint of this noise reappearing. Over the next couple of days I'll give it new oil and a filter and follow the tips you mentioned Pete.

 

I suppose the strangest thing to me was the fact that I have left the car for longer periods in the past and not encountered this. Before this fortnight the car was untouched for 2 months, it was only due to circumstances that I've been home twice in 2 weeks and run the engine both times. Only a week ago the car was running fine, no noticable problems and left it running for a good while.

 

You do make an interesting point Kev, I just hope in running it I haven't caused it major damage!

[dr_mat 0]

You're unlikely to do a lot of damage with a couple of isolated warm-ups at idle, but it's a bad practice for many reasons.

- the world can do without burning half a gallon of oil for no reason for a start, not to mention the local air pollution

- as Kev mentioned - acid erosion (get some colgate?)

- piston slap is much worse at idle (get 2000 rpm onto the engine and the pistons have enough inertia to avoid it, mostly)

- prolonged rich running at idle means the cylinder head gets coked up more than it should because there's just not enough air flow to burn it all out

- it's annoying as fook for your neighbours! :)

 

Just charge the battery and leave the car alone unless you're going to actually drive it... :)

[Danny B 0]

That was actually a very interesting read of replys ...... fanjita I hope it sorts itself out with no problems !!

[Fanjita 1]

Thanks Danny,

As we all know this is what the forum's great for, knowledgable people whom are always very willing to help!

 

The car is acting fine now, can hardly hear it at idle anymore just got the usual tappet rattle at 2k rpm!

 

flew through the MOT and will be changing the oil before I leave tomorrow. Fingers crossed it makes the 170 mile trip!

[rixy 0]

cool man, glad its all worked out ok for ya. As someone has said, and intersting set of reply's :-)

 

I didnt realise about not starting cars in storage etc....its a good job i havent started mine for a while, ha ha. Poor thing is hiding away in the end of a container, feeling unloved.... :help: