Melted pistons :(

Fingle · Post by **Fingle** » 14 Oct 2008, 20:20

Yep defiantely sounded a bit more throaty, but not boy racer style. (ive had exhaust issues with other cars, but I guess I havent been 14 ft away before)

Only sounded a little bit odd going past walls and cars (you know how you can hear better when u do that)

Post by **HarryMann** » 14 Oct 2008, 20:23

The only catalyst I can tell was me dinking the back into a lamppost on the rear drivers side, naroowly missing the exhaust, altho I sepculate the exhaust may have suffered a knock (could this have knocked something else, like a heat exchanger ?)

How long ago did that happen, and is the exhaust leaking - or not? That is, did it start it blowing and if so how long has it been..

Post by **VWCamperfan** » 14 Oct 2008, 20:25

Oh yes! I know exactly what you mean! My exhaust isn't the quietest on the road! Not by choice though... Was meant to be quieter than my last one but sounds like I forgot to put it on! Bliidy stupid noise rating numbers!

Fingle · Post by **Fingle** » 14 Oct 2008, 20:53

HarryMann wrote:
The only catalyst I can tell was me dinking the back into a lamppost on the rear drivers side, naroowly missing the exhaust, altho I sepculate the exhaust may have suffered a knock (could this have knocked something else, like a heat exchanger ?)

How long ago did that happen, and is the exhaust leaking - or not? That is, did it start it blowing and if so how long has it been..

Was roughly a month ago, seemed fine on the way to Oktoberfest tho, and back.

Fingle · Post by **Fingle** » 14 Oct 2008, 20:57

It is diffucult to tell from so far in front, I have to put my hands up and say, I dont honestly know if it was blowing or not. As the only driver, i never get to hear, and with a 6yr old and a 5 month old baby walrus in the back its hard to listen

Post by **HarryMann** » 14 Oct 2008, 20:59

So far, it's possible that you've burnt an exhaust valve and its running on 3 cylinders.. expect the compression tests will show at least one cyl. significantly down.

Post by **HarryMann** » 14 Oct 2008, 21:02

Let's wait and see the compressions then...

Post by **Rozzo** » 14 Oct 2008, 23:23

when did you last put a set of sparkplugs in m8

could be a 2 bob fix,, fingers crossed heh

don't worry about the oil leak, they all do that

and when you top it up just keep it half way between the marks on the dipstick cos if you fill it even a smidgen above the top mark, the oil runs into the cylinders on roundabouts etc and can oil the plugs up and smoke like a diesel.

Post by **jpee** » 15 Oct 2008, 00:59

when was the last service? could be anything from bad plugs to rotor REALLY doesn't sound like piston 'melt' that would be distinctive and disastrous, Engine wouldn't start if you had piston melt. Get van to garage (independent preferably)

Fingle · Post by **Fingle** » 15 Oct 2008, 07:07

Shes with an independant garage down the road, GSF put us onto him. Hes worked aircooleds for years.

He said it was "internal" so im guessing he checked the plugs etc, il wait till the compression results.

Again, aplologies for the panic, feel a proper tit now

Post by **Mr Bean** » 15 Oct 2008, 09:20

VWCamperfan wrote:Ahh, could be a lack of back pressure due to a leaking exhaust system somewhere. If the exhaust is more noisy than usual then this could be the problem. It could also explain the cracked head. Look for signs of carbon deposits around exhaust system espicially near heads.

Exhaust back pressure is critical on two stroke engines however most run of the mill four strokes will probably benefit from reduced back pressure in the exhaust sytem. Hence the riduculouse bashed out exhaust sound of the boy racers and middle age now rich discoverers of lost youth. Although with bad exhaust leaks there could be a tendency to run slightly leaner which in itself can cause overheating. In performance engines this can melt pistons etc. Things do get more complicated in modern engine set ups but we are talking 20 year old technology here. So I would suggest we all back off on the remote diagnosis front and see what the hands-on man suggests. The forum help may be required "ANALysing" the diagnosis and helping get it fixed at a fair price.
No offence meant
Smiffy

Post by **VWCamperfan** » 15 Oct 2008, 16:34

Citizen Smith wrote:So I would suggest we all back off on the remote diagnosis front and see what the hands-on man suggests.

May as well close the technical questions and answers forum then...!

Post by **HarryMann** » 15 Oct 2008, 20:26

I think he means hang fire till there is some real info coming in...

Post by **VWCamperfan** » 15 Oct 2008, 20:27

Fingle · Post by **Fingle** » 16 Oct 2008, 10:16

Right the results of the compression tests :

0 compression in cyl 4, only 130 in opp one

He reckons its shot and needs a new engine, says it could be the piston.

Thinks there is a rattle at the bottom end, and suggests metal etc could be flying around in the oil.

Also says there are other parts missing from engine (as well as vac advance system, ie an accelerator damper (?) and a few more.

He doesnt actually do any work like replacing engines, so cant see what he has to gain from saying this (says he has worked on aircoooleds scince the 70s) Did have a mate that could do it tho...

Opinions ?